Category: Storm Tracker

Flash Flood Warning: Northern Fillmore and Mower Counties Until 1 AM CDT
Status: ACTIVE — Flash Flood Warning until 1:00 AM CDT Saturday, September 19. A Flash Flood Warning is in effect right now for northern Fillmore and northern Mower counties in southeastern Minnesota, issued by the National Weather Service in La Crosse at 11:51 PM CDT Friday. This one is observed and already causing damage: local law enforcement reports trees washed down at Highway 43 from south Rushford to Bratsberg, and flooding along Minnesota Highway 16 between Wayland and Peterson. Between 3 and 6 inches of rain have fallen, with another 1 to 3 inches possible. Flash flooding is already occurring.

This is the most damage-forward of tonight’s three active southeastern Minnesota warnings — confirmed road flooding, washed-out trees, and the heaviest rainfall totals of the night. For restoration contractors, a warning with observed highway flooding is the one that produces the Saturday call surge: stranded vehicles, flooded road-adjacent properties, and basements that filled while the rain kept falling at up to 3 additional inches. This is a live snapshot as of 12:35 AM CDT Saturday, September 19. Conditions change fast — always verify with the National Weather Service for your specific county or ZIP code.

Northern Fillmore and Mower Counties — Flash Flood Warning

Issued: 11:51 PM CDT Friday, September 18, by the National Weather Service in La Crosse (KARX).
Expires: 1:00 AM CDT Saturday, September 19.
Area: Northern Fillmore and northern Mower counties, Minnesota.
Severity: Severe · Certainty: Likely · Urgency: Immediate.

At 11:51 PM CDT, local law enforcement reported thunderstorms producing heavy rain. The detection is observed — officers on the ground have confirmed it, and the damage reports are already specific:
- Trees were washed down at Highway 43 from south Rushford to Bratsberg.
- Minnesota Highway 16 between Wayland and Peterson has flooding reported along the highway.
- This includes Interstate 90 in Minnesota between mile markers 193 and 204.
Rainfall totals so far, per the NWS:
- Between 3 and 6 inches of rain have fallen — the heaviest totals of any warning active in Minnesota tonight.
- Additional rainfall amounts of 1 to 3 inches are possible in the warned area.
- Flash flooding is already occurring.
HAZARD: Flash flooding caused by thunderstorms.
SOURCE: Law enforcement reported.
IMPACT: Flash flooding of small creeks and streams, urban areas, highways, streets and underpasses as well as other poor drainage and low-lying areas.

Some locations that will experience flash flooding include: Chatfield, Rushford, Grand Meadow, Lanesboro, Brownsdale, Wykoff, Fountain, Lansing, Rushford Village, Washington, Racine, Mayville, Dexter, Pilot Mound, Arendahl, Peterson, Waltham, and Whalan.

Source links: NWS La Crosse office page · the official NWS alert (FFSARX).

Stay safe tonight

Turn around, don’t drown. When you encounter a flooded road, do not attempt to cross it — most flood deaths occur in vehicles, and the flooding on Highway 16 and Highway 43 tonight is the proof. It takes only a few inches of moving water to sweep a car away. Be especially cautious tonight: it is harder to recognize the dangers of flooding after dark, and this warning runs through 1 AM.

If water is entering your home:
- Stay out of standing water where electricity may be present. Do not enter a flooded basement until power is confirmed off.
- Avoid the basement until the water recedes and the electrical situation is verified safe.
- Photograph everything before cleanup begins. Documentation matters for insurance — shoot the water line, the affected rooms, and any damaged contents before anything is moved or torn out.
- Call a local restoration contractor quickly. Water left sitting starts a second wave of damage — saturated drywall, wicking into framing, and mold growth — within a day.
What this means for restoration teams

Three to six inches of rain with observed highway flooding is the call profile that restoration owners in the Driftless Area know well: the Rushford corridor floods hard and fast, low-lying homes along the Root River tributaries take water first, and the I-90 corridor between mile markers 193 and 204 becoming part of the warning zone means commercial properties along the interstate — hotels, truck stops, strip retail — are in the damage footprint too.

What to expect from the call volume:
- Commercial calls will mix with residential. When an interstate corridor is named in a flash flood warning, expect water-intrusion calls from businesses along it — flooded parking lots pushing water into ground-floor units, loading docks, and lobbies.
- The dawn wave will be the biggest of the night. Overnight flash-flood calls typically surface between 5 and 8 AM. With the heaviest rainfall totals in the state tonight, the Rushford–Chatfield–Lanesboro triangle should be staffed for a busy Saturday morning.
- Washed-down trees mean access problems. Trees down at Highway 43 from south Rushford to Bratsberg signal blocked roads and delayed response. Quote arrival windows with the road situation in mind, and triage by severity.
- Sewage backup risk is elevated. In small towns, 3 to 6 inches of rain overwhelms combined systems. Ask every caller about odor — that determines PPE, category classification, and disposal protocol.
- Mold clock starts now. Porous materials soaked tonight reach the 24–48 hour mold window by Sunday. Contractors with drying equipment staged and an on-call rotation running win this wave.
The play: stage equipment now — dehumidifiers, air movers, extraction units, moisture meters. Keep an on-call rotation through Saturday morning. On the first call, capture the address, the water source (rain intrusion vs. sewage backup vs. sump failure), and every affected room. Photo-document before mitigation starts, moisture-map every affected room, and keep the homeowner’s payment responsibility clear in writing before work begins.

FEMA & federal assistance

If your home or business is damaged and a federal disaster is later declared for your county, help may be available through FEMA. The FEMA Helpline is 1-800-621-3362 (7 a.m.–10 p.m. local time, 7 days a week). You can also apply at DisasterAssistance.gov or through the FEMA app, and find recovery centers at fema.gov/drc.

Basic eligibility: U.S. citizenship or qualified status, identity verification, proof of occupancy or ownership of the damaged property, and unmet needs not covered by insurance. Apply as soon as it is safe to do so — and document your damage thoroughly before cleanup, because adjusters and FEMA inspectors both work from what you can show.

Looking ahead

This warning expires at 1:00 AM CDT — the shortest fuse of the night, and the one expiring first. That does not mean the danger lifts at 1 AM: with 3 to 6 inches of rain on the ground and washed-out roads already reported, creeks and streams in Fillmore and Mower counties can keep rising for hours after the rain stops, and any follow-up round of storms on saturated ground can re-trigger flooding with almost no lead time. Watch for an extension or a new warning from NWS La Crosse.

The demand window for restoration work opens as the water recedes: water-intrusion calls typically start within hours and keep coming for days as people discover damage — wet carpet that seemed fine, baseboards that wicked overnight, musty odors that surface Sunday. Contractors who run Saturday-morning inspection routes through Rushford, Chatfield, and the Highway 16 corridor will find the work the overnight storm left behind.

Sources & how to verify
- NWS Flash Flood Warning FFSARX — official alert text
- NWS La Crosse office
- weather.gov — enter your county or ZIP code for your local warnings
To verify for your own county or ZIP: go to weather.gov, enter your location, and check the alerts box at the top of your local forecast page — or visit your NWS office page directly.

This post is for informational purposes and is not an official weather warning. Always follow instructions from local authorities and the National Weather Service.
September 19, 2026
Flash Flood Warning: Fillmore County Until 3:45 AM CDT
Status: ACTIVE — Flash Flood Warning until 3:45 AM CDT Saturday, September 19. The National Weather Service in La Crosse has issued a Flash Flood Warning for southern Fillmore County in southeastern Minnesota, effective 11:46 PM CDT Friday. Doppler radar and automated rain gauges indicate thunderstorms producing heavy rain across the warned area: between 1 and 3.5 inches of rain have fallen, with another 1 to 3 inches possible. Flash flooding is ongoing or expected to begin shortly.

This is the second of three active flash flood warnings across southeastern Minnesota tonight — a multi-county rain event that is still unfolding while most of the warned area sleeps. For restoration contractors, this is the overnight scenario that fills the Saturday call board: water moving into basements, crawl spaces, and low-lying commercial buildings hours before anyone is awake to see it. This is a live snapshot as of 12:30 AM CDT Saturday, September 19. Conditions change fast — always verify with the National Weather Service for your specific county or ZIP code.

Southern Fillmore County — Flash Flood Warning

Issued: 11:46 PM CDT Friday, September 18, by the National Weather Service in La Crosse (KARX).
Expires: 3:45 AM CDT Saturday, September 19.
Area: Southern Fillmore County in southeastern Minnesota.
Severity: Severe · Certainty: Likely · Urgency: Immediate.

At 11:46 PM CDT, Doppler radar and automated rain gauges indicated thunderstorms producing heavy rain across the warned area. Detection is radar and gauge indicated — automated gauges on the ground are confirming what the radar shows.

Rainfall totals so far, per the NWS:
- Between 1 and 3.5 inches of rain have fallen across the warned area.
- Additional rainfall amounts of 1 to 3 inches are possible in the warned area.
- Flash flooding is ongoing or expected to begin shortly.
HAZARD: Flash flooding caused by thunderstorms.
SOURCE: Radar and automated gauges.
IMPACT: Flash flooding of small creeks and streams, urban areas, highways, streets and underpasses as well as other poor drainage and low-lying areas.

Some locations that will experience flash flooding include: Preston, Spring Valley, Harmony, Mabel, Canton, Highland, Cherry Grove, Bristol, Newburg, Amherst, York, Carimona, Ostrander, Hutton, Granger, Forestville State Park, Greenleafton, and Henrytown.

Source links: NWS La Crosse office page · the official NWS alert (FFWARX).

Stay safe tonight

Turn around, don’t drown. When you encounter a flooded road, do not attempt to cross it — most flood deaths occur in vehicles, and even a few inches of fast-moving water can carry a car away. Be especially cautious tonight: it is harder to recognize the dangers of flooding after dark, and this warning runs until nearly 4 AM.

If water is entering your home:
- Stay out of standing water where electricity may be present. Do not enter a flooded basement until power is confirmed off.
- Avoid the basement until the water recedes and the electrical situation is verified safe.
- Photograph everything before cleanup begins. Documentation matters for insurance — shoot the water line, the affected rooms, and any damaged contents before anything is moved or torn out.
- Call a local restoration contractor quickly. Water left sitting starts a second wave of damage — saturated drywall, wicking into framing, and mold growth — within a day.
What this means for restoration teams

Southern Fillmore County is hill country — the Root River valley, steep bluffs, and towns like Preston, Lanesboro-area corridors, and Harmony sitting in drainage paths that concentrate runoff fast. With 1 to 3.5 inches already down and another 1 to 3 possible, this is exactly the profile that produces basement seepage, overwhelmed sump systems, and water pushing through foundation walls in older housing stock.

What to expect from the call volume:
- The wave starts at dawn. Overnight flash-flood calls typically surface between 5 and 8 AM as people wake to wet basements. Staff the phones for Saturday morning.
- Sump-pump failures will be a major call driver. When rain falls this fast on saturated ground, sump systems run continuously — and the ones with aging pumps or no battery backup fail at the worst moment. Ask callers whether they have a sump and whether it’s running.
- Rural properties and state-park-adjacent cabins are in the mix. Forestville State Park is inside the warned area, and seasonal properties with no one home are the jobs that get discovered days later — the mold jobs. If you serve the Preston/Spring Valley corridor, a Saturday drive-by route through low-lying areas can surface work before homeowners even call.
- Mold clock starts now. Porous materials soaked tonight reach the 24–48 hour mold window by Sunday. The contractors who win this wave are the ones with drying equipment staged and an on-call rotation already running.
The play: stage equipment now — dehumidifiers, air movers, extraction units, moisture meters. Keep an on-call rotation through Saturday morning. On the first call, capture the address, the water source (rain intrusion vs. sewage backup vs. sump failure), and every affected room. Photo-document before mitigation starts, moisture-map every affected room, and keep the homeowner’s payment responsibility clear in writing before work begins.

FEMA & federal assistance

If your home or business is damaged and a federal disaster is later declared for your county, help may be available through FEMA. The FEMA Helpline is 1-800-621-3362 (7 a.m.–10 p.m. local time, 7 days a week). You can also apply at DisasterAssistance.gov or through the FEMA app, and find recovery centers at fema.gov/drc.

Basic eligibility: U.S. citizenship or qualified status, identity verification, proof of occupancy or ownership of the damaged property, and unmet needs not covered by insurance. Apply as soon as it is safe to do so — and document your damage thoroughly before cleanup, because adjusters and FEMA inspectors both work from what you can show.

Looking ahead

This warning runs until 3:45 AM CDT — the longest of tonight’s southeastern Minnesota warnings — which tells you the NWS expects the heavy rain to persist. When it expires, the danger does not necessarily end: creeks and streams in Fillmore County can crest hours after the rain stops, and saturated bluff-country ground means even a light follow-up round can re-trigger flooding with almost no lead time. Watch for an extension or additional warnings from NWS La Crosse if rain rates hold.

The demand window for restoration work opens as the water recedes: water-intrusion calls typically start within hours and keep coming for days as people discover damage — wet carpet that seemed fine, baseboards that wicked overnight, musty odors that surface Sunday. Contractors who run Saturday-morning inspection routes through Preston, Spring Valley, and Harmony will find the work the overnight storm left behind.

Sources & how to verify
- NWS Flash Flood Warning FFWARX — official alert text
- NWS La Crosse office
- weather.gov — enter your county or ZIP code for your local warnings
To verify for your own county or ZIP: go to weather.gov, enter your location, and check the alerts box at the top of your local forecast page — or visit your NWS office page directly.

This post is for informational purposes and is not an official weather warning. Always follow instructions from local authorities and the National Weather Service.
September 19, 2026
Flash Flood Warning: Waseca Area Until 1 AM CDT
Status: ACTIVE — Flash Flood Warning until 1:00 AM CDT Saturday, September 19. A Flash Flood Warning is in effect right now for parts of south-central Minnesota — southeastern Blue Earth, northeastern Faribault, northwestern Freeborn, southwestern Steele, and southern Waseca counties — issued by the National Weather Service in Twin Cities/Chanhassen at 11:26 PM CDT Friday. Law enforcement has already reported flooding along MN Highway 30 in southern Waseca County and in the town of New Richland, with 2 to 5 inches of rain on the ground and rain still falling at a rate of 1 to 2 inches per hour.

For restoration teams, this is the shape of the year’s heaviest water-intrusion nights: overnight basement and crawl-space flooding that homeowners discover at dawn, when the calls start stacking. This is a live snapshot as of 12:25 AM CDT Saturday, September 19. Conditions change fast — always verify with the National Weather Service for your specific county or ZIP code.

Waseca and Surrounding Counties — Flash Flood Warning

Issued: 11:26 PM CDT Friday, September 18, by the National Weather Service in Twin Cities/Chanhassen (KMPX).
Expires: 1:00 AM CDT Saturday, September 19.
Counties: Southeastern Blue Earth, northeastern Faribault, northwestern Freeborn, southwestern Steele, and southern Waseca counties, Minnesota.
Severity: Severe · Certainty: Likely · Urgency: Immediate.

At 11:26 PM CDT, local law enforcement reported thunderstorms producing heavy rain in southern Waseca County along MN Highway 30 and in New Richland. The detection is observed — this is not a radar-only call; officers on the ground have confirmed it.

Rainfall totals so far, per the NWS:
- Between 2 and 5 inches of rain have fallen across the warned area.
- The expected rainfall rate is 1 to 2 inches in 1 hour.
- Additional rainfall amounts of 0.5 to 2 inches are possible before the warning expires.
- Flash flooding is already occurring.
HAZARD: Flash flooding caused by thunderstorms.
SOURCE: Law enforcement reported.
IMPACT: Flash flooding of small creeks and streams, urban areas, highways, streets and underpasses as well as other poor drainage and low-lying areas.

Locations that will experience flash flooding include: New Richland, Ellendale, Minnesota Lake, Geneva, Hartland, and Matawan.

Source links: NWS Twin Cities/Chanhassen office page · the official NWS alert (FFSMPX).

Stay safe tonight

Turn around, don’t drown. When you encounter a flooded road, do not attempt to cross it — most flood deaths occur in vehicles, and it takes only a few inches of moving water to sweep a car away. Be especially cautious tonight: it is harder to recognize the dangers of flooding after dark, and this warning runs through the early-morning hours.

If water is entering your home:
- Stay out of standing water where electricity may be present. Do not walk through a flooded basement until power is confirmed off.
- Avoid the basement until the water recedes and the electrical situation is verified safe.
- Photograph everything before cleanup begins. Documentation matters for insurance — shoot the water line, the affected rooms, and any damaged contents before anything is moved or torn out.
- Call a local restoration contractor quickly. Water left sitting starts a second wave of damage — saturated drywall, wicking into framing, and mold growth — within a day.
What this means for restoration teams

This is an observed, already-occurring flash flood event across five counties in south-central Minnesota, and it is hitting overnight — the worst possible window for damage to go unnoticed. The signature damage profile from a night like this: basement water intrusion through window wells and foundation seepage, saturated carpet and pad, wicking drywall, and crawl-space standing water that homeowners won’t find until morning.

What to expect from the call volume:
- The wave starts at dawn. Overnight flash-flood calls typically surface between 5 and 8 AM as people wake to wet basements. Staff the phones accordingly.
- Sewage backup risk is real in low-lying areas. With 2 to 5 inches of rain plus another 1 to 2 inches per hour possible, municipal systems in small towns like New Richland and Ellendale can be overwhelmed. Ask every caller whether the water smells — that determines PPE, category classification, and disposal protocol.
- Highway flooding means delayed response. With MN-30 already flooding, drive times across the warned area will stretch. Quote arrival windows honestly and triage by severity.
- Mold clock starts now. Porous materials soaked tonight reach the 24–48 hour mold window by Sunday. The contractors who win this wave are the ones with drying equipment staged and an on-call rotation already running.
The play: stage equipment now — dehumidifiers, air movers, extraction units, moisture meters. Keep an on-call rotation through Saturday morning. On the first call, capture the address, the water source (rain intrusion vs. sewage backup vs. sump failure), and every affected room. Photo-document before mitigation starts, moisture-map every affected room, and keep the homeowner’s payment responsibility clear in writing before work begins.

FEMA & federal assistance

If your home or business is damaged and a federal disaster is later declared for your county, help may be available through FEMA. The FEMA Helpline is 1-800-621-3362 (7 a.m.–10 p.m. local time, 7 days a week). You can also apply at DisasterAssistance.gov or through the FEMA app, and find recovery centers at fema.gov/drc.

Basic eligibility: U.S. citizenship or qualified status, identity verification, proof of occupancy or ownership of the damaged property, and unmet needs not covered by insurance. Apply as soon as it is safe to do so — and document your damage thoroughly before cleanup, because adjusters and FEMA inspectors both work from what you can show.

Looking ahead

When this warning expires at 1:00 AM CDT, the danger does not necessarily end with it. Creeks and streams in the warned counties can crest hours after the rain stops, and saturated ground means any additional round of storms — even a light one — can re-trigger flooding with almost no lead time. Watch for a possible extension or a new warning from NWS Twin Cities/Chanhassen if rain rates hold.

The demand window for restoration work opens as the water recedes: water-intrusion calls typically start within hours and keep coming for days as people discover damage — wet carpet that seemed fine, baseboards that wicked overnight, musty odors that surface Sunday. Contractors who follow up with Saturday-morning inspections in New Richland, Ellendale, and Minnesota Lake will find the work the overnight storm left behind.

Sources & how to verify
- NWS Flash Flood Warning FFSMPX — official alert text
- NWS Twin Cities/Chanhassen office
- weather.gov — enter your county or ZIP code for your local warnings
To verify for your own county or ZIP: go to weather.gov, enter your location, and check the alerts box at the top of your local forecast page — or visit your NWS office page directly.

This post is for informational purposes and is not an official weather warning. Always follow instructions from local authorities and the National Weather Service.
September 19, 2026

Storm Updates: Carolinas Wind Pulse + Upper Mississippi Flood Slight — Friday, September 18, 2026

This is a live Friday afternoon snapshot of U.S. local-storm activity as of Friday, September 18, 2026. The Storm Prediction Center 2000 UTC Day 1 Convective Outlook holds a Marginal Risk of isolated severe thunderstorms from the Carolina Piedmont into northern Georgia, northern Iowa, parts of the central High Plains, and parts of the Intermountain West. No convective watches are valid. Mesoscale discussions referenced in the 2000 UTC package (MCDs 2306 and 2307) are no longer in effect. The Weather Prediction Center Day 1 Excessive Rainfall Outlook is the organized ticket: Slight Risk over portions of the Upper Mississippi Valley and a second Slight Risk over southwest Montana. There is no named tropical cyclone in the Atlantic, eastern Pacific, or central Pacific.

These are county- and ZIP-scale thunderstorms and flash-flood pulses, not a mainland hurricane landfall. Restoration exposure this afternoon is wind and trees already verifying across central North Carolina, isolated hail leftover from Intermountain cells, and water tonight from southeast Minnesota into west-central Wisconsin. Conditions change fast. Verify with the National Weather Service for the specific county or ZIP before you roll.

What is live this afternoon

SPC issued the 2000 UTC Day 1 Convective Outlook at 0241 PM CDT, valid 182000Z–191200Z. Forecasters Chalmers and Wendt made only minor adjustments from the midday package. Headline: an isolated severe risk continues for portions of the Carolinas into northern Georgia and parts of the Intermountain West. Isolated severe storms are also forecast later today across portions of northern Iowa and parts of the central High Plains. Risk-area population centers listed by SPC include Charlotte, Atlanta, Raleigh, Greensboro, and Durham. Categorical risk is Marginal only. No Slight Risk on Day 1. No tornado probabilities in the 2000 UTC categorical headline. Risk-area size on the 2000 UTC graphic is about 179,316 square miles covering roughly 19.6 million people.

Current convective watches: none. SPC watch page last updated 1805 UTC Friday: no watches currently valid. Most recently issued watch remains Severe Thunderstorm Watch 669, already expired. Do not treat 669 as a live product.

The 2000 UTC discussion points to MCDs 2306 and 2307 for additional information. By late afternoon the live MD list showed no mesoscale discussions currently in effect. Most recently issued discussion on the current-MD page was 2305. Treat those numbers as the latest issued discussions, not standing watches.

WPC Day 1 excessive-rainfall language valid 16Z Friday through 12Z Saturday holds Slight Risk for portions of the Upper Mississippi Valley and southwest Montana. The 16Z update expanded the eastern edge of the Slight and high-end Slight about one to two counties into southeast Wisconsin and northeast Illinois, where recent heavy rain left the ground sensitive. Highest amounts still focus over southeast Minnesota and west-central Wisconsin, with model-consensus QPF in the 2 to 4 inch range. A separate Slight Risk covers southwest Montana. Marginal Risk remains over South Florida and the Keys, a remnant Intermountain/Southwest terrain corridor, a Northern Plains strip, and a thin Ohio Valley pocket. WPC’s short-range discussion already flags a Moderate Risk of excessive rainfall Saturday over parts of the Upper Great Lakes into the Middle Mississippi Valley. That is tomorrow’s water upgrade, not today’s Day 1 map.

Hotspot 1 — Carolina Piedmont into northern Georgia

A wavy stationary front this morning ran from southern Illinois through southern Indiana and southern Ohio into southwest Pennsylvania. Decaying showers preceded it from southern Illinois into northern Kentucky. The boundary is shifting south as cooler air follows a shortwave through southern Quebec and the Canadian Maritimes. The front is relatively weak, but it is interacting with a warm, moist, diurnally destabilized airmass across the Carolina Piedmont and northern Georgia. Precipitable water is over 2 inches. Vertical shear is weak. Storm mode is outflow-dominant. The risk is occasionally strong downbursts, not a long-lived supercell corridor.

That language already verified this afternoon. Preliminary LSRs on the 18/1200Z cycle include a 69 mph gust at KGSO (5 ESE Colfax, Guilford County), a 66 mph gust at KFAY (4 ENE Hope Mills, Cumberland County), trees down on I-85 near Route 68, trees blocking roads in Randolph, Davie, Iredell, Rowan, Chatham, and Moore counties, and a power-company outage from downed trees northwest of Craven in Rowan County. Those are trees-on-pavement and trees-on-wires tickets in the Charlotte–Greensboro–Fayetteville corridor, not a watch-scale outbreak.

Restoration read: wind first. Stage tree, tarp, and board-up capacity for the Piedmont counties that already have LSRs. Hail is not the lead threat on this corridor. Water is secondary unless a cell trains over the same ZIP that already took a 2-inch precipitable-water plume.

Hotspot 2 — Upper Mississippi Valley water

A Northern Plains disturbance continues east from the Dakotas across southern Minnesota into Wisconsin tonight. WPC keeps the Slight Risk and high-end Slight focused on southeast Minnesota and west-central Wisconsin, with the eastern edge nudged into southeast Wisconsin and northeast Illinois because those counties already took rain. Local NWS language from La Crosse this afternoon still has 1–3 inches likely and 4–6 inches possible in pockets, with a Flood Watch south of I-94 and rivers such as the Kickapoo at Gays Mills and Viola and the Cedar at Charles City expected to reach minor flood stage if the heavier corridor verifies.

SPC’s northern Iowa Marginal is a separate overlay: elevated storms tonight on warm-air advection and a moderate low-level jet, with isolated hail the primary severe hazard and a strong gust or two if any linear structures develop. That is hail and wind on the southern edge of the water corridor, not a Slight Risk severe day.

Restoration read: water first from southeast Minnesota through west-central Wisconsin into northeast Iowa tonight. Extraction and wet-drywall clocks start the same night if water is inside. Do not send the same crew to a Piedmont tree job and a Kickapoo basement without checking which county has a warning now.

Hotspot 3 — Intermountain West and central High Plains

A shortwave trough continues east into southern Idaho and northern Utah. Highs stay relatively cool — upper 60s in southern Idaho, low to mid 70s in northern Utah — but cold temperatures aloft plus strong deep-layer shear still support organized updrafts. Isolated severe gusts and small hail remain the SPC language. That already verified on today’s LSR cycle: 1.50-inch hail 2 W of Kaysville in Davis County, Utah, and quarter-size hail near Farmington in San Juan County, New Mexico.

On the High Plains, a mid-level vorticity maximum lifting north-northeast later this evening may support isolated severe gusts and a conditional, less-than-5-percent hail risk if a more cellular mode holds into better low-level moisture near the Colorado–Nebraska–Kansas border. Storms may grow upscale into a small eastward-moving cluster this evening. Isolated outflow surges, not a derecho.

Restoration read: hail first if cells verify over the Wasatch Front or the Four Corners. Wind second if High Plains clusters organize. Flash-flood risk on this corridor is Marginal to isolated except for the separate southwest Montana Slight Risk, where WPC introduced Slight coverage after Thursday’s cell behavior and 0.5–1.5 inch guidance.

Just hit

SPC preliminary storm reports for the current 18/1200Z–19/1159Z cycle already include one brief landspout at Lighthouse Point in Broward County, Florida (palm fronds lofted; no damage path described as a supercell tornado), quarter to 1.50-inch hail in San Juan County, New Mexico, and Davis County, Utah, and a long list of North Carolina wind reports from Davie, Guilford, Randolph, Cumberland, Iredell, Rowan, Chatham, and Moore counties, including measured 69 mph at Greensboro and 66 mph at Fayetteville.

The last 24-hour ticket pile on the prior cycle (17/1200Z–18/1159Z) is the Idaho hail outbreak the morning desk already logged: tennis-ball hail (2.50 inches) near Rose in Bingham County, golf-ball hail in Blackfoot and Shelley, quarter to 1.25-inch hail across Bingham, Blaine, Jefferson, and Bear Lake counties, plus 1.50-inch hail at Midway, Wasatch County, Utah, and 1.50-inch hail near Broadwater, Morrill County, Nebraska. Wind on that cycle included power lines down at Lewisville, Jefferson County, Idaho; a 61 mph gust south-southwest of Mud Lake; trees in Beavercreek, Greene County, Ohio; a tree-fall injury in Ashland, Boyd County, Kentucky; and trees in Tippecanoe and Carroll counties, Indiana. A brief tornado touchdown was reported 11 NNE of Chappell in Garden County, Nebraska. Those products are expired. The roofs and cars in Bingham County are still the ticket.

This morning’s Storm Tracker already covered the 1300 UTC outlook family. This afternoon desk updates to the 2000 UTC package, confirms still-zero watches, and adds the live North Carolina LSR cluster and the WPC 16Z flood-edge nudge into southeast Wisconsin and northeast Illinois.

Pulse table

Region	Main threats	SPC / NWS / WPC level	Status this afternoon
Carolina Piedmont / northern GA	Downburst wind, trees, wires	SPC Marginal	Live — LSRs already in
SE MN / west-central WI / NE IA	Flash flood, 2–4″ swaths	WPC Slight (high-end core)	Tonight’s organized water ticket
Northern Iowa / far southern MN	Isolated hail, isolated gusts	SPC Marginal	Elevated storms tonight
Southern ID / northern UT / Four Corners	Isolated hail and severe gusts	SPC Marginal	Live cells; 1.50″ hail at Kaysville
Central High Plains	Isolated severe gusts	SPC Marginal	Evening cluster if heating holds
Southwest Montana	Flash flood, 0.5–1.5″	WPC Slight	Diurnal terrain cells
South Florida / Keys	Urban flooding, landspout noise	WPC Marginal	Diurnal; one brief landspout LSR
Bingham County ID (overnight)	Tennis-ball to golf-ball hail	LSRs prior cycle	Just-hit
Atlantic / Gulf vs. U.S. mainland	No named cyclone	NHC: no tropical cyclones	Quiet on the mainland coast

What this means for restoration teams

The live ticket this afternoon is wind on the Carolina Piedmont: trees, wires, and a measured 66–69 mph pair at Greensboro and Fayetteville. Isolated Intermountain hail is a roof and auto-glass survey if cells keep firing over the Wasatch Front or Farmington, New Mexico. The organized ticket tonight is still water from southeast Minnesota through west-central Wisconsin. Idaho’s overnight tennis-ball hail around Blackfoot, Rose, and Shelley is a separate just-hit staffing problem from this afternoon’s Piedmont wind.

For teams near the Carolina Marginal: the warnings and LSRs are already out. Photograph damage in daylight if it is safe, call the carrier, and start extraction the same night if water is inside. Turn around, don’t drown on Upper Mississippi and Montana washes.

What this is not

This is not a Slight Risk severe day, not a live convective watch, and not a U.S. mainland hurricane landfall. MCDs 2306 and 2307 are not watches. The Broward landspout is a brief landspout LSR, not a tornado outbreak. NHC reports no tropical cyclones in the Atlantic, eastern Pacific, or central Pacific as of this afternoon. The work, if it keeps verifying, will be scattered: a tree swath through a Piedmont county, a hail report on the Wasatch Front, and heavier rain over southeast Minnesota and west-central Wisconsin tonight.

Looking ahead

SPC Day 2 (Saturday) holds a Slight Risk of severe thunderstorms late Saturday afternoon and evening from northwest Oklahoma into eastern Kansas, with more isolated severe storms possible across the central High Plains, central Rockies, and the Midwest to Southeast. The 1730 UTC Day 2 summary calls for scattered severe wind and hail-producing storms on the central Plains. WPC already has a Moderate Risk of excessive rainfall Saturday over parts of the Upper Great Lakes into the Middle Mississippi Valley. The next Storm Tracker update should re-check the 0100 UTC Day 1 outlook, any new watches, and whether that Moderate flood risk is the morning headline rather than assuming today’s Marginal stays the last word.

Sources and how to verify

Primary sources: NOAA Storm Prediction Center Sep 18, 2026 2000 UTC Day 1 Convective Outlook (Chalmers/Wendt); Day 2 Convective Outlook; current convective watches (none valid; last issued Watch 669); current mesoscale discussions (none in effect); SPC preliminary storm reports for the 20260918 cycle and 20260917 cycle; Weather Prediction Center Day 1 Excessive Rainfall Outlook (Campbell, 332 PM EDT Fri Sep 18, 2026); National Hurricane Center Tropical Weather Outlook, September 18, 2026 (no tropical cyclones in the Atlantic, eastern Pacific, or central Pacific).

Check weather.gov for the county warning, spc.noaa.gov for the outlook, watch, MD, and LSRs, and WPC excessive rainfall for the flood overlay. Morning desk for this calendar day: Storm Updates: Carolinas–Georgia + Iowa Marginal, Upper Mississippi Flood Slight — Friday, September 18, 2026 (Morning).

Informational only — not an official weather warning. Follow local authorities and the National Weather Service. Turn around, don’t drown.

September 18, 2026

Storm Updates: Carolinas–Georgia + Iowa Marginal, Upper Mississippi Flood Slight — Friday, September 18, 2026 (Morning)

This is a live Friday morning snapshot of U.S. local-storm activity as of early Friday, September 18, 2026. Overnight convection dumped tennis-ball hail on Bingham County, Idaho, knocked power lines down near Lewisville, and forced National Weather Service flash-flood warnings for the Idaho Falls and Rexburg areas that expired before dawn. The Storm Prediction Center 1300 UTC Day 1 outlook holds a Marginal Risk of isolated severe thunderstorms from the Carolinas into northern Georgia, across Iowa, over parts of the central High Plains, and again in the Intermountain West. No convective watches are valid. The Weather Prediction Center Day 1 Excessive Rainfall Outlook holds Slight Risks over the Upper Mississippi Valley and southwest Montana. There is no named tropical cyclone threatening U.S. land.

These are county- and ZIP-scale thunderstorms and flash-flood pulses, not a mainland hurricane landfall. Restoration exposure today is leftover hail and interior water in eastern Idaho, isolated damaging gusts on the Carolina Piedmont and in Iowa this afternoon, and training rain from southern Minnesota into Wisconsin tonight. Conditions change fast. Verify with the National Weather Service for the specific county or ZIP before you roll.

What is live this morning

SPC issued the 1300 UTC Day 1 Convective Outlook at 0719 AM CDT. Valid 181300Z–191200Z. Headline: an isolated severe risk later today into the evening for the Carolinas into northern Georgia, Iowa, parts of the central High Plains, and parts of the Intermountain West. Categorical risk is Marginal over about 171,000 square miles and roughly 21 million people. Wind is the shared 5 percent contour. A 2 percent tornado contour sits over north-central Iowa (Ames, Ankeny, Mason City, Fort Dodge, Marshalltown). A 5 percent hail contour remains over the Salt Lake City–Provo corridor.

No Severe Thunderstorm Watch or Tornado Watch is in effect. The most recently issued watch on the SPC board is Watch 669, already expired. Today’s 1200 UTC–onward local storm report page is empty as of this desk: no tornado, hail, or wind reports on the new cycle yet. Last night’s work is on the September 17 cycle.

WPC’s 1034 UTC Day 1 Excessive Rainfall Outlook, valid 12Z Friday through 12Z Saturday, holds a Slight Risk of rainfall exceeding flash-flood guidance over the Upper Mississippi Valley (southern Minnesota into Wisconsin and adjacent Iowa/Illinois) and a separate Slight over southwest Montana. Marginal flood pockets cover leftover Southwest terrain, the northern High Plains, South Florida and the Keys, a Midwest/Great Lakes corridor, and the Ohio Valley into the central Appalachians. Guidance still supports 2 to 4 inches in the better Upper Midwest swath.

The National Hurricane Center 800 AM EDT Atlantic outlook and companion eastern and central Pacific outlooks list no tropical cyclones. That sentence stays off the restoration board unless NHC names something that threatens U.S. land.

Overnight into this morning

Thursday’s SPC report cycle (1200 UTC September 17 through 1159 UTC September 18) is the just-hit file. One brief tornado was reported 11 miles north-northeast of Chappell in Garden County, Nebraska, around 0034 UTC. Hail clustered on eastern Idaho: 1.00 to 1.75 inches around Blackfoot, Shelley, Firth, Moreland, and Menan; 2.50 inches (tennis ball) one mile north-northeast of Rose in Bingham County; 1.25 inches at Gannett in Blaine County; 1.00 inch east of Alton in Bear Lake County. Utah added 1.50 inches at Midway in Wasatch County. Nebraska High Plains added 1.50 inches east-southeast of Broadwater. Missouri picked up 1.00 inch near Saint Paul in St. Charles County.

Wind: power lines down in Lewisville, Jefferson County, Idaho; 61 mph at the INL rover south-southwest of Mud Lake; trees and shingles near Saint Paul, Missouri; a 59 mph gust at Truth or Consequences, New Mexico; trees down in Tippecanoe and Carroll counties, Indiana; a large tree on Yalta Drive in Beavercreek, Ohio; several large trees in Ashland, Kentucky, with one person injured and transported when a tree fell. Overnight flash-flood warnings for the Idaho Falls area (until 2:00 AM MDT) and the Rexburg area (until 2:45 AM MDT) have expired. Those were water jobs on eastern Idaho drainages after the same hail cores, not a new watch this morning.

Hotspot 1 — Carolinas into northern Georgia

A cluster of weak thunderstorms this morning over Kentucky and West Virginia rides south on northerly flow around a mid-level high over the Ark-La-Tex. SPC expects rejuvenation near convective outflow along the Virginia–North Carolina border, then scattered storms over the Piedmont into northern Georgia as the boundary layer heats. Isolated 50–60 mph gusts are the advertised threat. Cities inside the Marginal contour include Charlotte, Raleigh, Greensboro, and Atlanta.

Restoration read: wind first, not a tornado outbreak. Stage tarps and tree crews for late afternoon into evening. Photograph roofs in remaining daylight only if it is safe. This is a scatter of cores, not a watch-boxed line.

Hotspot 2 — Iowa and the Upper Mississippi Valley

A front lies from the lower Ohio Valley west into the mid Missouri Valley, with a weak surface low over western Nebraska. Lower-70s dewpoints sit south of the boundary. SPC favors thunderstorms over Iowa into far southern Minnesota where heating and low-level forcing erode inhibition. Primary hazard is marginally severe gusts. Enlarged hodographs near the warm front leave a localized chance of a couple of weak, short-lived supercells — that is the 2 percent tornado contour, not a Slight Risk upgrade. Upscale growth late evening would drift toward the southwest Great Lakes and lose buoyancy.

WPC’s Slight Risk is the organized water ticket. A disturbance tracking out of the Dakotas across southern Minnesota into Wisconsin can support 2–4 inches where the low-level jet blossoms the rain shield. That is wet drywall and a 24–48 hour mold clock in the better swaths, not a river-flood headline yet.

Restoration read: Iowa wind this afternoon, Minnesota–Wisconsin water tonight. Do not staff both with the same crew without checking which county has a warning now.

Hotspot 3 — Intermountain West and central High Plains

A mid-level trough crosses the Intermountain West. Dewpoints in the 50s from northern Utah into western Wyoming valleys, MLCAPE 1000–1200 J/kg, and moderate shear support isolated severe gusts and hail again late afternoon and evening — the same corridor that just put tennis-ball hail on Bingham County. On the High Plains, a vorticity maximum over New Mexico may help isolated storms grow into a small eastward cluster over eastern Colorado into southwest Nebraska and northwest Kansas, with isolated severe gusts on outflow.

Southwest Montana sits under WPC’s second Slight Risk after Thursday’s cell behavior and ensemble 2-inch QPF. Rates can still beat flash-flood guidance even if storms stay progressive. Residual Marginal flood language covers New Mexico and Arizona terrain for one more diurnal cycle.

Just hit

Eastern Idaho hail, the expired Idaho Falls and Rexburg flash-flood warnings, the Garden County brief tornado, and the Ashland, Kentucky tree injury are yesterday’s tickets. Thursday afternoon’s Storm Tracker already carried the Idaho–Utah Marginal and Dakotas flood Slight on the prior Day 1 package. This morning desk moves the live outlook east onto the Carolinas and Iowa and slides the flood Slight onto the Upper Mississippi Valley and southwest Montana.

Pulse table

Region	Main threats	SPC / NWS / WPC level	Status this morning
Carolinas / northern GA	Isolated 50–60 mph gusts	SPC Marginal	Afternoon–evening cells
Iowa / southern MN	Gusts; localized brief tornado	SPC Marginal; 2% tornado	Afternoon into evening
Southern MN / WI / adjacent IA–IL	Flash flood, 2–4″ swaths	WPC Slight	Today’s organized water ticket
Northern UT / ID / WY valleys	Isolated hail and severe gusts	SPC Marginal (5% hail UT)	Late afternoon–evening
E CO / SW NE / NW KS	Isolated severe gusts	SPC Marginal	Evening cluster possible
Southwest Montana	Flash flood on progressive cells	WPC Slight	Afternoon–evening
Bingham / Jefferson / Madison ID	Hail, wires, expired FFWs	Aftermath	Just-hit desk
Atlantic / Gulf vs. U.S. mainland	No landfalling cyclone	NHC quiet	Quiet

What this means for restoration teams

Idaho hail is already on cars, windows, and roofs in Bingham County. That is same-day emergency board-up and a multi-day supplement fight, not a forecast. Carolina and Iowa wind at 50–60 mph is roof, siding, gutter, and tree-on-structure work if cores verify. Upper Mississippi Valley rain is extraction and drying if 2–4 inch swaths land on saturated ground. A 2 percent tornado contour is a narrow, short-lived threat — staff it as a local damage survey if a warning verifies, not as a regional event.

For teams near Charlotte, Raleigh, Atlanta, Des Moines, Ames, or the Salt Lake valley: stage before peak heating, not after the first warning. Property owners should photograph damage in daylight if it is safe, call the carrier, and start extraction the same night if water is inside.

What this is not

This is not a Slight Risk convective day, not a live watch, and not a U.S. mainland hurricane landfall. The work today, if it comes, will be scattered: a wind-damaged street on the Piedmont, a brief spin-up near an Iowa warm front, another hail core in a Utah or Idaho valley, a flooded underpass in southern Minnesota or Wisconsin. That is the local-storm pattern this desk should staff.

Looking ahead

Saturday’s Day 2 outlook is already a Slight Risk of scattered severe wind and hail over portions of the central Plains, with isolated severe storms possible from the High Plains and central Rockies into the Midwest and Southeast. Sunday is Marginal. Day 4–8 has no 15 percent areas. Watch the afternoon Storm Tracker for the 1630 UTC Day 1 update rather than assuming this morning’s Marginal is the last line of the weekend.

Sources and how to verify

Primary sources: NOAA Storm Prediction Center Sep 18, 2026 1300 UTC Day 1 Convective Outlook (Smith/Mead); SPC current watches page (none valid; last watch 669); SPC local storm reports for 20260917 and 20260918; Weather Prediction Center Day 1 Excessive Rainfall Outlook issued 1034 UTC Friday; National Hurricane Center 800 AM EDT Friday Tropical Weather Outlook; National Weather Service Pocatello flash-flood warning text for Idaho Falls and Rexburg, now expired.

Check weather.gov for the county warning, spc.noaa.gov for the outlook, watch, and LSRs, and WPC excessive rainfall for the flood overlay. Prior desk: Thursday afternoon Storm Updates: Idaho–Utah Marginal, Dakotas Flood Slight. Related overnight posts: Idaho Falls flash-flood warning and Rexburg flash-flood warning.

Informational only — not an official weather warning. Follow local authorities and the National Weather Service. Turn around, don’t drown.

September 18, 2026

Flash Flood Warning: Rexburg Area Until 2:45 AM MDT

A Flash Flood Warning is active right now for the Rexburg area. The National Weather Service in Pocatello issued it at 9:51 PM MDT on Thursday, September 17, and it runs until 2:45 AM MDT on Friday, September 18. Doppler radar is showing thunderstorms producing heavy rain across central Madison County, and flash flooding is ongoing or expected to begin shortly. These are exactly the storms that produce the interior water-intrusion jobs restoration teams see most — water finding its way into living spaces in the middle of the night. This is a live snapshot as of 12:06 AM MDT on Friday, September 18. Conditions change fast — always verify with the National Weather Service for your specific county or ZIP code.

Rexburg area — Flash Flood Warning

Issued by: National Weather Service, Pocatello, Idaho — 9:51 PM MDT Thursday, September 17.
Expires: 2:45 AM MDT Friday, September 18.
Covers: Central Madison County in southeastern Idaho.

At 9:51 PM MDT, Doppler radar indicated thunderstorms producing heavy rain across the warned area. The National Weather Service says flash flooding is ongoing or expected to begin shortly.

Hazard: Flash flooding caused by thunderstorms.
Source: Radar indicated.

Expected impacts: Flash flooding of small creeks and streams, urban areas, highways, streets and underpasses, as well as other poor-drainage and low-lying areas. In practical terms: ponding on Rexburg streets, water over low road crossings, and any creek or drainage running high after this rain.

Locations in the warning path: Rexburg.

Also active nearby — Big Rock burn scar warning: At 10:25 PM MDT, NWS Pocatello issued a separate Flash Flood Warning for the Big Rock burn scar in south central Madison County and southeastern Jefferson County, running until 2:30 AM MDT — and part of that polygon sits inside Madison County, close to home for Rexburg readers. Thunderstorms are producing heavy rain over the burn scar, and the Weather Service warns of life-threatening flash flooding with debris flow — rock, mud, vegetation and other loose materials — moving through the scar. Some locations affected include Heise. Roads and driveways may be washed away in places. If you are anywhere near the burn scar area and encounter flood waters, climb to safety immediately. This is the more dangerous of the two warnings tonight: debris flow does not behave like ordinary street flooding.

Stay safe tonight

Turn around, don’t drown. Most flood deaths occur in vehicles — never drive through flooded roadways, and never try to guess the depth of water over a road at night. The National Weather Service’s rule of thumb: six inches of moving water can knock an adult off their feet, and twelve inches can carry a car.

If water gets into your home: stay out of standing water anywhere electricity may be present, and stay out of the basement until the water recedes and the power is confirmed off. Photograph everything before you touch anything — documentation matters for insurance. Then call a local restoration contractor. Water left sitting starts a second wave of damage within a day, and the clock on that starts the moment the rain stops, not the moment you discover it.

What this means for restoration teams

This is the signature southeastern Idaho night for water work: radar-indicated storms, urban and small-stream flooding, and a warning window that runs to 2:45 AM. Expect the calls to start as water recedes and keep coming for days as people discover what happened overnight. The damage categories to plan for: interior water intrusion through foundations, window wells and door thresholds; saturated drywall and insulation in finished basements; mold risk inside 24 to 48 hours on anything that stays wet; and sewage backup in low-lying areas where storm drains surcharge.

The play tonight: stage equipment now rather than at first call. Pre-position drying assets — air movers, dehumidifiers, extraction — so the first truck rolls complete. Keep an on-call rotation through the morning, because the discovery curve on overnight flooding peaks after sunrise. On the first call, capture the address, the water source, and every affected area before you quote anything.

Field discipline, same as always: photo-document before mitigation begins, moisture-map every affected room (not just the visibly wet one — water travels inside wall cavities), and keep the homeowner’s payment responsibility clear in writing before work starts. Night jobs with stressed homeowners are where scope misunderstandings are born.

Local emergency contacts

Madison County Emergency Services (Rexburg): (208) 359-3010
Life-threatening emergency: 911
Idaho Office of Emergency Management: ioem.idaho.gov

FEMA and federal assistance

If the flooding damages your home and you need help beyond what insurance covers, the FEMA Helpline is 1-800-621-3362, open 7 a.m. to 10 p.m. local time, seven days a week. You can also apply at DisasterAssistance.gov, through the FEMA app, or find a recovery center at fema.gov/drc.

Basic eligibility: U.S. citizenship or qualified status, identity verification, proof of occupancy or ownership, and unmet needs not covered by insurance. Don’t wait — apply as soon as it’s safe.

Looking ahead

The Rexburg warning expires at 2:45 AM MDT, and the neighboring burn scar warning at 2:30 AM MDT. When a warning expires, that doesn’t mean the water is gone — small creeks and streams often crest after the rain ends, and saturated ground means any additional round of storms overnight floods faster than the first. Storms can arrive in multiple rounds overnight, so watch the NWS Pocatello page for extensions or new warnings.

For contractors: the demand window on this kind of event opens within hours of water receding and stays open for days. Homeowners discover basement water in the morning, call around midday, and the serious mitigation decisions land over the weekend. Be reachable, be first with the moisture map, and be the contractor who documented everything.

Sources and how to verify

NWS Pocatello office page — warnings, updates and extensions post here first.
weather.gov — enter your ZIP code for the warnings covering exactly where you are.
Alert data via the National Weather Service API (api.weather.gov), warnings active as of 12:06 AM MDT Friday, September 18.

To verify for your own county or ZIP: open weather.gov, enter your ZIP, and read the active alerts banner at the top of the page. If Madison County is listed, this warning covers you.

This post is for informational purposes and is not an official weather warning. Always follow instructions from local authorities and the National Weather Service. Stay weather-aware around flash flooding — turn around, don’t drown.

September 18, 2026
Flash Flood Warning: Idaho Falls Area Until 2 AM MDT

A Flash Flood Warning is active right now for the Idaho Falls area. The National Weather Service in Pocatello issued it at 10:00 PM MDT on Thursday, September 17, and it runs until 2:00 AM MDT on Friday, September 18. Doppler radar is showing thunderstorms producing heavy rain across north central Bonneville County and south central Jefferson County, and flash flooding is ongoing or expected to begin shortly. These are exactly the storms that produce the interior water-intrusion jobs restoration teams see most — water finding its way into living spaces in the middle of the night. This is a live snapshot as of 12:06 AM MDT on Friday, September 18. Conditions change fast — always verify with the National Weather Service for your specific county or ZIP code.

Idaho Falls area — Flash Flood Warning

Issued by: National Weather Service, Pocatello, Idaho — 10:00 PM MDT Thursday, September 17.
Expires: 2:00 AM MDT Friday, September 18.
Covers: North central Bonneville County and south central Jefferson County in southeastern Idaho.

At 10:00 PM MDT, Doppler radar indicated thunderstorms producing heavy rain across the warned area. The National Weather Service says flash flooding is ongoing or expected to begin shortly.

Hazard: Flash flooding caused by thunderstorms.
Source: Radar indicated.

Expected impacts: Flash flooding of small creeks and streams, urban areas, highways, streets and underpasses, as well as other poor-drainage and low-lying areas. In practical terms: the underpasses and low dips around Idaho Falls, ponding on streets in Rigby and the smaller towns, and any creek or drainage running high after this rain.

Locations in the warning path: Idaho Falls, Rigby, Lorenzo, Ucon, Menan and Lewisville.

Also active nearby — Big Rock burn scar warning: At 10:25 PM MDT, NWS Pocatello issued a separate Flash Flood Warning for the Big Rock burn scar in southeastern Jefferson County and south central Madison County, running until 2:30 AM MDT. Thunderstorms are producing heavy rain over the burn scar, and the Weather Service warns of life-threatening flash flooding with debris flow — rock, mud, vegetation and other loose materials — moving through the scar. Some locations affected include Heise. Roads and driveways may be washed away in places. If you are anywhere near the burn scar area and encounter flood waters, climb to safety immediately. This one is the more dangerous of the two warnings tonight.

Stay safe tonight

Turn around, don’t drown. Most flood deaths occur in vehicles — never drive through flooded roadways, and never try to guess the depth of water over a road at night. The National Weather Service’s rule of thumb: six inches of moving water can knock an adult off their feet, and twelve inches can carry a car.

If water gets into your home: stay out of standing water anywhere electricity may be present, and stay out of the basement until the water recedes and the power is confirmed off. Photograph everything before you touch anything — documentation matters for insurance. Then call a local restoration contractor. Water left sitting starts a second wave of damage within a day, and the clock on that starts the moment the rain stops, not the moment you discover it.

What this means for restoration teams

This is the signature southeastern Idaho night for water work: radar-indicated storms, urban and small-stream flooding, and a warning window that runs past 2:00 AM. Expect the calls to start as water recedes and keep coming for days as people discover what happened overnight. The damage categories to plan for: interior water intrusion through foundations, window wells and door thresholds; saturated drywall and insulation in finished basements; mold risk inside 24 to 48 hours on anything that stays wet; and sewage backup in low-lying areas where storm drains surcharge.

The play tonight: stage equipment now rather than at first call. Pre-position drying assets — air movers, dehumidifiers, extraction — so the first truck rolls complete. Keep an on-call rotation through the morning, because the discovery curve on overnight flooding peaks after sunrise. On the first call, capture the address, the water source, and every affected area before you quote anything.

Field discipline, same as always: photo-document before mitigation begins, moisture-map every affected room (not just the visibly wet one — water travels inside wall cavities), and keep the homeowner’s payment responsibility clear in writing before work starts. Night jobs with stressed homeowners are where scope misunderstandings are born.

Local emergency contacts

Bonneville County Emergency Management: (208) 529-1220 — bonnevillecountyidaho.gov/county-departments/emergency-management
Life-threatening emergency: 911
Bonneville County non-emergency dispatch: (208) 529-1200
Idaho Office of Emergency Management: ioem.idaho.gov

FEMA and federal assistance

If the flooding damages your home and you need help beyond what insurance covers, the FEMA Helpline is 1-800-621-3362, open 7 a.m. to 10 p.m. local time, seven days a week. You can also apply at DisasterAssistance.gov, through the FEMA app, or find a recovery center at fema.gov/drc.

Basic eligibility: U.S. citizenship or qualified status, identity verification, proof of occupancy or ownership, and unmet needs not covered by insurance. Don’t wait — apply as soon as it’s safe.

Looking ahead

The Idaho Falls warning expires at 2:00 AM MDT, and the neighboring burn scar warning at 2:30 AM MDT. When a warning expires, that doesn’t mean the water is gone — small creeks and streams often crest after the rain ends, and saturated ground means any additional round of storms overnight floods faster than the first. Storms can arrive in multiple rounds overnight, so watch the NWS Pocatello page for extensions or new warnings.

For contractors: the demand window on this kind of event opens within hours of water receding and stays open for days. Homeowners discover basement water in the morning, call around midday, and the serious mitigation decisions land over the weekend. Be reachable, be first with the moisture map, and be the contractor who documented everything.

Sources and how to verify

NWS Pocatello office page — warnings, updates and extensions post here first.
weather.gov — enter your ZIP code for the warnings covering exactly where you are.
Alert data via the National Weather Service API (api.weather.gov), warnings active as of 12:06 AM MDT Friday, September 18.

To verify for your own county or ZIP: open weather.gov, enter your ZIP, and read the active alerts banner at the top of the page. If Bonneville or Jefferson County is listed, this warning covers you.

This post is for informational purposes and is not an official weather warning. Always follow instructions from local authorities and the National Weather Service. Stay weather-aware around flash flooding — turn around, don’t drown.

September 18, 2026

Storm Updates: Idaho–Utah Marginal, Dakotas Flood Slight — Thursday, September 17, 2026

This is a live Thursday afternoon snapshot of U.S. local-storm activity as of Thursday, September 17, 2026. The Storm Prediction Center 2000 UTC Day 1 Convective Outlook holds a Marginal Risk of isolated severe wind gusts and hail this afternoon and evening over parts of Idaho and Utah and a small part of the central High Plains. No convective watches are valid. Mesoscale Discussion 2304 covers southern and central Idaho with a 20 percent chance of a watch. The Weather Prediction Center Day 1 Excessive Rainfall Outlook remains the organized ticket: Slight Risk over portions of the north-central Plains and Midwest and over the southwestern U.S. There is no named tropical cyclone in the Atlantic, eastern Pacific, or central Pacific.

These are county- and ZIP-scale thunderstorms and flash-flood pulses, not a mainland hurricane landfall. Restoration exposure this afternoon is isolated hail and wind if cells verify over the Snake River Plain and Wasatch Front, plus water from the Wyoming Front Range across South Dakota into southwest Minnesota and leftover Southwest terrain. Conditions change fast. Verify with the National Weather Service for the specific county or ZIP before you roll.

What is live this afternoon

SPC issued the 2000 UTC Day 1 Convective Outlook at 0247 PM CDT, valid 172000Z–181200Z. Forecasters Chalmers and Weinman made no changes from the midday package. Headline: thunderstorms with isolated severe wind gusts and hail will be possible over parts of the Intermountain West this afternoon and evening. A few strong to severe gusts may also occur across portions of the central High Plains. Risk-area population centers listed by SPC include Salt Lake City, West Valley City, Provo, West Jordan, and Orem. Categorical risk is Marginal only. No Slight Risk. No tornado probabilities in the 2000 UTC package. The Ohio Valley Marginal from Wednesday remains off the map.

Current convective watches: none. SPC watch page last updated 2059 UTC Thursday: no watches currently valid. Most recently issued watch remains Severe Thunderstorm Watch 669, already expired. Do not treat 669 as a live product.

MCD 2304, issued 0246 PM CDT and valid 1946Z–2215Z, covers parts of southern and central Idaho. Concerning: severe potential, watch unlikely. Probability of watch issuance: 20 percent. Summary: the risk of a few severe storms capable of producing large hail and severe wind gusts will increase through the remainder of the afternoon. Most probable peak wind gust 55–70 mph. Most probable peak hail size 1.00–1.75 inches. Offices tagged: Pocatello, Missoula, Boise. By late afternoon the live MD list showed no mesoscale discussions currently in effect; treat 2304 as the latest issued discussion, not a standing watch.

WPC Day 1 excessive-rainfall language valid 12Z Thursday through 12Z Friday still has two Slight Risk corridors. One is a high-end Slight across much of South Dakota, expanding toward Sioux Falls and into southwestern Minnesota and northwest Iowa, and west-southwest to the Cheyenne, Wyoming region east of the Laramie Range. The other holds Slight Risk over New Mexico and eastern Arizona into the San Juans and western Colorado, with Marginal coverage into the Salt Lake corridor and southeastern Idaho. Wednesday’s Moderate Risk over southern and central Arizona is aftermath, not a live upgrade.

Hotspot 1 — Southern and central Idaho into northern Utah

Morning water vapor showed an upper low over northern California with a band of strong flow aloft and embedded shortwave troughs across Nevada into Utah and Idaho. Strong heating was expected to aid scattered thunderstorms from southern Idaho into northern Utah by mid-afternoon. Sufficient vertical shear is present for rotating updrafts capable of large hail and gusty or damaging winds. Coverage is limited. SPC still expects one or two severe cells later today, mainly over the eastern Snake River Plain. The 18Z Boise sounding in MCD 2304 sampled steep deep-layer lapse rates and an elongating, mostly straight hodograph with about 30–40 kt of cloud-layer shear. Cells first. Small clusters later if outflow organizes.

Overnight LSRs already put quarter-size hail at Huntington in Emery County and at East Carbon and Sunnyside in Carbon County. That is the same Salt Lake City forecast office that owns this afternoon’s Utah cells.

Restoration read: hail first if discrete cells fire over the Snake River Plain, Boise, Pocatello, or the Wasatch Front. Wind second if storms cluster. Stage roof and auto-glass survey capacity before the first warning, not after. Flash-flood risk on this corridor is Marginal to isolated, not the organized Dakotas ticket.

Hotspot 2 — Dakotas water corridor and the High Plains wind overlay

Remnants of a weak tropical low tracked northeast across the Four Corners this morning. Ample moisture and weak ascent support considerable clouds and scattered thunderstorms over the Colorado mountains and southern Wyoming, spreading east into eastern Colorado and western Nebraska and Kansas. High-based convection poses a risk of locally damaging wind gusts. Daytime heating is the limiter because of lingering cloud cover. That is the SPC Marginal overlay: isolated gusts, not a Slight Risk wind event.

WPC is more organized here than SPC. A tropical-origin shortwave ejecting out of Arizona pivots through the central Rockies and into the northern Plains tonight. Precipitable-water anomalies approach the 95th–99th percentile from South Dakota into southern Minnesota by the end of the period. Discussion language includes 2–4 inches, locally higher, with HREF neighborhood probabilities of greater than 2 inches at 50–80 percent across a large High Plains swath. The centroid of greater-than-3-inch probabilities sits just east and southeast of Rapid City into Badlands National Park. The Slight Risk was expanded east toward Sioux Falls for the last 6–8 hours of the forecast.

Restoration read: water first from the Wyoming Front Range across western and central South Dakota into southwest Minnesota and northwest Iowa tonight into Friday morning. Wind second if High Plains clusters organize. Do not send one crew to both a Cheyenne gust and a Rapid City wash without checking which county has a warning now.

Hotspot 3 — Southwest terrain leftover plus Ohio just-hit

The shortwave that drove Wednesday’s Arizona Moderate flood risk is leaving. WPC still keeps a Slight Risk over New Mexico and eastern Arizona into the San Juans and Sacramentos. Guidance still prints 1–3 inches on the Sangre de Cristos, San Juans, and interior New Mexico terrain. Sacramento Mountains burn-scar sensitivity remains in the discussion as locally Moderate impacts embedded inside a higher-end Slight. That is runoff on ground that already took water Wednesday, not a new Moderate upgrade.

Ohio is off today’s SPC Marginal. It is the just-hit desk. Overnight LSRs from the 16/1200Z–17/1159Z window include multiple trees down in Versailles and Piqua, a snapped hardwood onto a home awning in Darke County, barn sheet-metal loss and a blown silo near West Alexandria in Preble County, and trees and wires southeast of Mansfield in Richland County. NWS Cleveland had severe thunderstorm warnings into mid-evening Wednesday for Richland, Ashland, Holmes, and Knox counties. Those products are expired. The trees are still on the lines.

Just hit

SPC preliminary storm reports for the current 17/1200Z–18/1159Z cycle show no tornado, hail, or wind reports as of this afternoon desk. That is expected. The Intermountain and High Plains threats are still an afternoon and evening problem.

The last 24-hour ticket pile sits on the prior cycle (16/1200Z–17/1159Z): no tornadoes. Hail: 1.00 inch at Huntington, Emery County, Utah; 1.00 inch at East Carbon and Sunnyside, Carbon County, Utah; 1.00 to 1.25 inches near Linn Creek, Camden County, Missouri, with two-foot-diameter limbs down. Wind: downed power lines in Mesa, Maricopa County, Arizona; trees in Versailles, Darke County, and Piqua and Lockington, Miami County, Ohio; a snapped pole and large limb near Broken Arrow, Tulsa County, Oklahoma; a power line and a condo-garage roof near Osage Beach and Linn Creek, Missouri; barn roofing and a grain silo near West Alexandria, Preble County, Ohio; trees and wires southeast of Mansfield.

This morning’s Storm Tracker already covered the same outlook family at 1300 UTC. This afternoon desk updates to the 2000 UTC package, adds MCD 2304, and confirms still-zero watches and still-zero LSRs on today’s cycle.

Pulse table

Region	Main threats	SPC / NWS / WPC level	Status this afternoon
Southern / central ID into northern UT	Isolated hail and severe gusts; possible small clusters	SPC Marginal; MCD 2304 watch unlikely	Live afternoon–evening cells
NE CO / western NE / High Plains	Isolated severe gusts	SPC Marginal	Late afternoon clusters if heating punches
WY Front Range / SD / SW MN / NW IA	Flash flood, 2–4″ swaths	WPC Slight (high-end over SD)	Today’s organized water ticket
NM / E AZ / San Juans / Sacramentos	Flash flood, burn-scar debris flow	WPC Slight; leftover from Wed Moderate	Diurnal terrain cells
Western / north-central OH	Trees, wires, barn and roof damage	LSRs overnight; warnings expired	Just-hit
Emery / Carbon UT; Camden MO	Quarter to half-dollar hail	LSRs overnight	Just-hit / same offices own today’s risk
Atlantic / Gulf vs. U.S. mainland	No named cyclone	NHC: no tropical cyclones	Quiet on the mainland coast

What this means for restoration teams

Isolated severe hail on the Snake River Plain and Wasatch Front is a roof and auto-glass survey ticket if cells verify over Boise, Pocatello, Salt Lake, or Provo. Isolated High Plains gusts are tree, siding, and gutter work in a thin corridor. The organized ticket today is still water from the Wyoming Front Range across South Dakota into southwest Minnesota and northwest Iowa tonight. Flash flooding on leftover Arizona–New Mexico terrain is wet drywall and a same-night extraction clock if water is inside a structure that already took rain Wednesday. Ohio trees-on-wires from last night are a separate staffing problem from this afternoon’s West.

For teams near the Intermountain Marginal: stage before mid-afternoon local. Property owners should photograph damage in daylight if it is safe, call the carrier, and start extraction the same night if water is inside. Turn around, don’t drown on High Plains and Southwest washes.

What this is not

This is not a Slight Risk severe day, not a live convective watch, and not a U.S. mainland hurricane landfall. MCD 2304 is watch-unlikely, not a watch. NHC reports no tropical cyclones in the Atlantic, eastern Pacific, or central Pacific as of this afternoon. The work, if it verifies, will be scattered: a hail swath through an Idaho or Utah county, a gust cluster on the High Plains, and heavier rain over South Dakota terrain tonight.

Looking ahead

SPC Day 2 (Friday, 1730 UTC package) holds Marginal Risk of isolated severe storms across parts of Idaho and Utah, Nebraska and Iowa, and the Piedmont of the Carolinas into north Georgia. Population centers listed on that outlook include Charlotte, Atlanta, Omaha, Lincoln, and Greensboro. WPC’s Day 1 water corridor over the Dakotas is the bridge into the Plains Marginal. The next Storm Tracker update should re-check the 0100 UTC Day 1 outlook and any new watches rather than assuming this afternoon’s Marginal stays the last word.

Sources and how to verify

Primary sources: NOAA Storm Prediction Center Sep 17, 2026 2000 UTC Day 1 Convective Outlook (Chalmers/Weinman); Mesoscale Discussion 2304 (Weinman/Hart); current convective watches (none valid; last issued Watch 669); SPC preliminary storm reports for the 20260917 cycle and 20260916 cycle; Weather Prediction Center Day 1 Excessive Rainfall Outlook (Kleebauer); National Hurricane Center Tropical Weather Outlook, September 17, 2026; NWS warning text archive including Cleveland OH overnight products now expired.

Check weather.gov for the county warning, spc.noaa.gov for the outlook, watch, MD, and LSRs, and WPC excessive rainfall for the flood overlay. Morning desk for this calendar day: Storm Updates: Intermountain West + High Plains Marginal, Dakotas Flood Slight — Thursday, September 17, 2026 (Morning).

Informational only — not an official weather warning. Follow local authorities and the National Weather Service. Turn around, don’t drown.

September 17, 2026

Storm Updates: Intermountain West + High Plains Marginal, Dakotas Flood Slight — Thursday, September 17, 2026 (Morning)

This is a live Thursday morning snapshot of U.S. local-storm activity as of early Thursday, September 17, 2026. Overnight convection left trees and wires down in western and north-central Ohio and quarter-to-half-dollar hail in eastern Utah and mid-Missouri. The Storm Prediction Center 1300 UTC Day 1 outlook holds a Marginal Risk of isolated severe wind gusts and hail across parts of Utah and Idaho into southwest Montana, plus a second Marginal over the central High Plains. No convective watches are valid. The Weather Prediction Center Day 1 Excessive Rainfall Outlook holds Slight Risks over portions of the north-central Plains and Midwest and over the southwestern U.S. There is no named tropical cyclone threatening U.S. land.

These are county- and ZIP-scale thunderstorms and flash-flood pulses, not a mainland hurricane landfall. Restoration exposure this morning is leftover wind and hail from last night plus a new afternoon hail/wind corridor in the Intermountain West and a water ticket on the Dakotas, Wyoming Front Range, and leftover Southwest terrain. Conditions change fast. Verify with the National Weather Service for the specific county or ZIP before you roll.

What is live this morning

SPC issued the 1300 UTC Day 1 Convective Outlook at 0730 AM CDT. Valid 171300Z–181200Z. Headline: thunderstorms with isolated severe wind gusts and hail will be possible over parts of the Intermountain West this afternoon and evening. A few strong to severe gusts may also occur across portions of the central High Plains. Risk-area population centers listed by SPC include Salt Lake City, West Valley City, Provo, West Jordan, and Orem. Categorical risk is Marginal only. No Slight Risk. No tornado probabilities in the 1300 UTC package. The Ohio Valley Marginal from Wednesday is off the map this morning. Poor lapse rates aloft and extensive cloud cover keep severe-wind probabilities below 5 percent from the Midwest through the Mid-Atlantic.

Current convective watches: none. Most recently issued watch remains Severe Thunderstorm Watch 669, already expired days ago. SPC watch page last updated 0849 UTC Thursday: no watches currently valid. That is the overnight close. Do not treat 669 as a live product.

WPC Day 1 excessive-rainfall language valid 12Z Thursday through 12Z Friday has two Slight Risk corridors. One covers a high-end Slight across much of South Dakota, expanding toward Sioux Falls and into southwestern Minnesota and northwest Iowa, and west-southwest to the Cheyenne, Wyoming region east of the Laramie Range. The other holds Slight Risk over New Mexico and eastern Arizona into the San Juans and western Colorado, with Marginal coverage into the Salt Lake corridor and southeastern Idaho. Wednesday’s Moderate Risk over southern and central Arizona is no longer the live upgrade. It is the just-hit and burn-scar follow-through desk.

Hotspot 1 — Utah, Idaho, and southwest Montana

A closed mid/upper-level low over northern California this morning will drift east across the northern Intermountain region. A 40–50 kt southwesterly mid-level jet and difluence aloft overspread the northern Great Basin this afternoon. SPC’s uncertainty is instability under morning cloud and ongoing rain. Upper-40s to low-50s dewpoints are already in place. Some guidance still builds 1000–1250 J/kg of MLCAPE over southeast Idaho and northern Utah if heating punches through. If that happens, a focused corridor of greater hail and wind potential exists because deep-layer shear is strong enough for supercells. Otherwise the threat is isolated hail and gusty winds with cells and small clusters across the northern Great Basin.

Overnight LSRs already put quarter-size hail at Huntington in Emery County and at East Carbon and Sunnyside in Carbon County. That is the same Salt Lake City forecast office that will own this afternoon’s cells.

Restoration read: hail first if discrete cells fire over the Wasatch Front and southeast Idaho. Wind second. Stage roof and auto-glass survey capacity in the Salt Lake–Provo–Boise belt before late afternoon, not after the first warning. Flash-flood risk on this corridor is Marginal to isolated, not the organized Dakotas ticket.

Hotspot 2 — Central High Plains and the Dakotas water corridor

Between the West Coast upper low and Southeast ridging, minor mid-level perturbations lift northeast from the Southwest toward the central High Plains by evening. SPC expects additional storms from northeast Colorado into western Nebraska late afternoon. Modest mid-level lapse rates should limit updraft intensity. Sufficient shear still allows a small cluster or two with isolated severe gusts spreading east-northeast through the evening. That is the wind overlay on top of WPC’s water story.

WPC is more organized here than SPC. A tropical-origin shortwave ejecting out of Arizona will pivot through the central Rockies and into the northern Plains tonight. Precipitable-water anomalies approach the 95th–99th percentile from South Dakota into southern Minnesota by the end of the period. Discussion language includes 2–4 inches, locally higher, with HREF neighborhood probabilities of greater than 2 inches at 50–80 percent across a large High Plains swath. The centroid of greater-than-3-inch probabilities sits just east and southeast of Rapid City into Badlands National Park. The Slight Risk was expanded east toward Sioux Falls for the last 6–8 hours of the forecast.

Hotspot 3 — Southwest terrain leftover plus Ohio just-hit

Just hit

SPC preliminary storm reports for the 16/1200Z–17/1159Z window show no tornadoes. Hail: 1.00 inch at Huntington, Emery County, Utah; 1.00 inch at East Carbon and Sunnyside, Carbon County, Utah; 1.00 to 1.25 inches near Linn Creek, Camden County, Missouri, with two-foot-diameter limbs down. Wind: downed power lines in Mesa, Maricopa County, Arizona; trees in Versailles, Darke County, and Piqua and Lockington, Miami County, Ohio; a snapped pole and large limb near Broken Arrow, Tulsa County, Oklahoma; a power line and a condo-garage roof near Osage Beach and Linn Creek, Missouri; barn roofing and a grain silo near West Alexandria, Preble County, Ohio; trees and wires southeast of Mansfield.

Today’s 17/1200Z cycle has no tornado, hail, or wind reports yet as of this morning desk. That is expected. The Intermountain and High Plains threats are an afternoon and evening problem.

Wednesday afternoon’s Storm Tracker already covered the Ohio Valley Marginal and the Arizona Moderate flood risk while they were live. This morning’s desk treats Ohio wind and Arizona washes as aftermath and moves the live outlook west and north.

Pulse table

Region	Main threats	SPC / NWS / WPC level	Status this morning
UT / ID / SW MT	Isolated hail and severe gusts; possible supercells if CAPE builds	SPC Marginal	Afternoon–evening cells
NE CO / western NE / High Plains	Isolated severe gusts	SPC Marginal	Late afternoon clusters
WY Front Range / SD / SW MN / NW IA	Flash flood, 2–4″ swaths	WPC Slight (high-end over SD)	Today’s organized water ticket
NM / E AZ / San Juans / Sacramentos	Flash flood, burn-scar debris flow	WPC Slight; leftover from Wed Moderate	Diurnal terrain cells
Western / north-central OH	Trees, wires, barn and roof damage	LSRs overnight; warnings expired	Just-hit
Emery / Carbon UT; Camden MO	Quarter to half-dollar hail	LSRs overnight	Just-hit / same offices own today’s risk
Atlantic / Gulf vs. U.S. mainland	No named cyclone	NHC: no tropical cyclones	Quiet on the mainland coast

What this means for restoration teams

Isolated severe hail on the Wasatch Front is a roof and auto-glass survey ticket if cells verify over Salt Lake, Provo, or southeast Idaho. Isolated High Plains gusts are tree, siding, and gutter work in a thin corridor. The organized ticket today is water from the Wyoming Front Range across South Dakota into southwest Minnesota and northwest Iowa tonight. Flash flooding on leftover Arizona–New Mexico terrain is wet drywall and a same-night extraction clock if water is inside a structure that already took rain Wednesday. Ohio trees-on-wires from last night are a separate staffing problem from this afternoon’s West.

What this is not

This is not a Slight Risk severe day, not a live convective watch, and not a U.S. mainland hurricane landfall. NHC reports no tropical cyclones in the Atlantic, eastern Pacific, or central Pacific as of this morning. Edouard is already in the archive. The work, if it verifies, will be scattered: a hail swath through a Utah or Idaho county, a gust cluster on the High Plains, and heavier rain over South Dakota terrain tonight.

Looking ahead

SPC Day 2 (Friday) holds Marginal Risk across parts of the northern Intermountain West, the central Great Plains into the southern middle Missouri Valley, and the Carolina–Georgia Piedmont. WPC’s Day 1 water corridor over the Dakotas is the bridge into that Plains Marginal. The next Storm Tracker update should re-check the 1630 UTC Day 1 outlook and any new watches rather than assuming this morning’s Marginal stays the last word.

Sources and how to verify

Primary sources: NOAA Storm Prediction Center Sep 17, 2026 1300 UTC Day 1 Convective Outlook (Gleason/Mead); current convective watches (none valid; last issued Watch 669); SPC preliminary storm reports for 20260916 1200 UTC–20260917 1159 UTC; Weather Prediction Center Day 1 Excessive Rainfall Outlook and discussion (Kleebauer); National Weather Service warning text including Cleveland OH, Salt Lake City, Springfield MO, and Phoenix/Flagstaff/Tucson overnight flood products now expired; National Hurricane Center 800 AM EDT Tropical Weather Outlook, September 17, 2026.

Check weather.gov for the county warning, spc.noaa.gov for the outlook, watch, and LSRs, and WPC excessive rainfall for the flood overlay. Prior desk: Wednesday, September 16 afternoon Storm Updates.

Informational only — not an official weather warning. Follow local authorities and the National Weather Service. Turn around, don’t drown.

September 17, 2026

Storm Updates: Ohio Valley Marginal, Arizona Flood Moderate — Wednesday, September 16, 2026

This is a live Wednesday afternoon snapshot of U.S. local-storm activity as of Wednesday, September 16, 2026. The Storm Prediction Center 2000 UTC Day 1 Convective Outlook still holds a Marginal Risk of isolated strong to severe thunderstorms over parts of northern Utah and parts of Ohio and vicinity. No convective watches are valid. Two mesoscale discussions are out this afternoon — MD 2302 for east-central Indiana into central Ohio and MD 2303 for northeastern Utah — both tagged severe potential, watch unlikely. The Weather Prediction Center Day 1 Excessive Rainfall Outlook still holds a Moderate Risk over portions of southern and central Arizona and the Sacramento Mountains of New Mexico. There is no named tropical cyclone threatening U.S. land.

What is organized this afternoon is water in the Southwest, not a Midwest derecho. Restoration exposure is isolated damaging wind or hail if a cell or small cluster holds together in Ohio or Utah, plus flash flood and burn-scar runoff where the monsoon plume sits over Arizona, New Mexico, southern Utah, and the San Juans. Conditions change by county. Verify with the National Weather Service before you roll.

What is live this afternoon

SPC issued the 2000 UTC Day 1 Convective Outlook at 0232 PM CDT, valid 162000Z–171200Z. Headline: isolated strong to severe thunderstorms appear possible today across parts of the Midwest/Ohio Valley and Utah/far northwest Colorado. The 20Z update said the forecast remains generally on track with only minor changes. Risk-area population centers listed by SPC include Columbus, Pittsburgh, Fort Wayne, Akron, and Salt Lake City. Categorical risk is Marginal only. No Slight Risk. No tornado probabilities.

Current convective watches: none. Most recently issued watch was Severe Thunderstorm Watch 669, already expired. Do not treat 669 as a live product.

MD 2302, issued 0246 PM CDT for east-central Indiana into central Ohio, valid through 162145Z: isolated thunderstorms near the Indiana/Ohio state line ahead of a stalled front. Temperatures in the 80s to near 90 F with mid-70s dewpoints. Effective shear 20–30 kt. Most probable peak gust up to 60 mph. Watch issuance probability 5 percent.

MD 2303, issued 0353 PM CDT for portions of northeastern Utah, valid through 162300Z: a developing supercell in a 500–1000 J/kg MLCAPE environment with 40–50 kt effective shear. Primary risk large hail (most probable 1.00–1.75 inches) plus isolated damaging gusts up to 60 mph. Watch issuance probability 20 percent. Watch still unlikely.

WPC Day 1 excessive rainfall, valid 12Z Wednesday through 12Z Thursday, keeps the organized water story in the Southwest. Moderate Risk over southern and central Arizona, including the Phoenix metro and the Mogollon Rim, and over the Sacramento Mountains of New Mexico around the Ruidoso burn-scar country. High-end Slight Risk covers much of Arizona into southern Utah, southwestern Colorado, and much of New Mexico. Isolated to widely scattered flash-flood prospects remain possible later across parts of Illinois, Indiana, and Ohio if cells train on the residual front, and again tonight along the I-80 corridor from Iowa into northern Illinois.

SPC preliminary storm reports for the current 16/1200Z–17/1159Z window show no tornado, hail, or wind reports as of this afternoon desk. Yesterday’s 15/1200Z–16/1159Z window is the just-hit file.

Hotspot 1 — East-central Indiana into central and eastern Ohio

SPC’s 1630 and 2000 UTC discussions keep the Ohio Valley on precip-loaded downdrafts, not supercells. PWAT values approaching 2 inches and steep low-level lapse rates can still produce strong or occasionally damaging winds. MD 2302 is the afternoon confirmation that cells are already firing near the state line. Coverage is widely scattered. Poor mid-level lapse rates should limit how long any one core lasts.

Overnight flash-flood warnings from Wilmington, Ohio, and Northern Indiana for Mercer County, Ohio, and Grant, Blackford, Adams, and Wells counties, Indiana, have expired. Those counties already took 1.5 to 3 inches before dawn. That water is still on the ground even if the warning product is dead.

Restoration read: wind first if a cluster organizes through early evening, then trees and lines. Water first in the counties that already flooded overnight. Stage tarps and tree crews in the Fort Wayne–Dayton–Columbus–Pittsburgh belt before the first new warning, not after it.

Hotspot 2 — Southern and central Arizona, Sacramento Mountains of New Mexico

This remains today’s organized flood ticket. WPC language still prints 2–3 inches, locally higher, where storms focus on the south-central Arizona desert including Phoenix and surrounds, the Mogollon Rim, southern Utah slot-canyon country from Zion toward Moab, the San Juans of Colorado, and the Sacramentos. Rates above 1 inch per hour for multiple hours are in the discussion. Burn-scar debris flow remains the life-safety language around Ruidoso and similar terrain.

SPC did not hang severe probabilities over Arizona and New Mexico on the 2000 UTC outlook. Water is the story. Gusty outflow is possible. Do not invent a severe-thunderstorm watch here.

Restoration read: extraction and drying on a 24–48 hour mold clock if cells stall over the same ZIP. Photograph interiors only when it is safe. Do not drive flooded washes. Turn around, don’t drown.

Hotspot 3 — Northeastern Utah into far northwest Colorado

Moisture has increased across Utah over the past 24 hours, with dewpoints in the low-to-mid 50s and PWAT over 1 inch. A band of 35–45 kt southwesterly mid-level flow is enough for a few rotating storms. MD 2303 is the live product on that cell: hail first, isolated wind second, watch unlikely. Grand Junction’s overnight flash-flood warning for the Lee Burn Scar in central Rio Blanco County expired before dawn. That scar can still run if another core sits on it.

Restoration read: isolated hail and wind tickets around the Wasatch Front and northeastern Utah valleys if the supercell holds. Burn-scar runoff is a separate life-safety problem from a roof-survey call in Salt Lake, West Valley, Provo, or Orem.

Just hit

SPC preliminary storm reports for 15/1200Z–16/1159Z show no tornadoes. Hail included 2.00 inches at Edgerton, Johnson County, Kansas; 1.75 inches west of Cairo, Randolph County, Missouri; 1.50 inches near Alta, Peoria County, Illinois; and 1.00-inch stones at Smyer, Texas, and Richmond, Missouri. Wind included 75 mph at McConnell Air Force Base in Sedgwick County, Kansas, with wall panels ripped at a nearby plant; 71 mph at Alva, Oklahoma, and railroad cars overturned east of Avard; 70 mph near Morton, Texas, and southeast of Hazelton, Kansas; an RV flipped west of Smyer, Texas; 67 mph south of Junction, Utah; trees and lines in Richmond and the Kansas City suburbs (Greenwood, Pleasant Hill, Lake Winnebago, west of Raytown); trees and lines in Congerville and Brimfield, Illinois; 65 mph near Wallen, Allen County, Indiana; numerous trees down near Lake Wawasee, Kosciusko County, Indiana; and power lines down near Humble City and Eunice, New Mexico.

Kansas City/Pleasant Hill still has river flood warnings on the Grand River near Chillicothe, Sumner, and Brunswick with crests later this week. That is channel water from Tuesday night, not a new convective watch. Tuesday afternoon’s Storm Tracker covered the Kansas–Missouri Moderate flood risk while it was live. This afternoon treats that corridor as aftermath plus river follow-through.

Pulse table

Region	Main threats	SPC / NWS / WPC level	Status this afternoon
East-central IN / central–eastern OH	Isolated damaging wind, leftover flash flood	SPC Marginal; MD 2302 watch unlikely	Cells live near the state line
Southern/central AZ, Sacramento Mtns NM	Flash flood, debris flow on burn scars	WPC Moderate excessive rainfall	Today’s organized water ticket
Northeastern UT / NW CO	Isolated hail and gusts, burn-scar runoff	SPC Marginal; MD 2303 watch unlikely	Supercell language this afternoon
NE KS / NW MO / Grand River	River flooding, wind/hail damage	Flood warnings; LSRs last night	Just-hit / in channel
IA / northern IL (tonight)	Training rain after 03Z	WPC Slight along I-80 corridor	Nocturnal pulse still ahead
Atlantic / Gulf vs. U.S. mainland	No named cyclone	NHC: no tropical cyclones	Quiet on the mainland coast

What this means for restoration teams

Wind at 60 mph is trees, lines, gutters, and isolated roof work — not a regional CAT. Two-inch hail from last night is already a roof-survey ticket in Johnson County, Kansas. Flash flooding on the Arizona–New Mexico Moderate Risk is wet drywall and a same-night extraction clock if water is inside. Grand River crests later this week are a separate staffing problem from today’s monsoon cells. Do not send one crew to both stories without checking which county has a warning now.

For teams near the Ohio Valley Marginal: the afternoon window is now, not tonight. Property owners should photograph damage in daylight if it is safe, call the carrier, and start extraction the same night if water is inside.

What this is not

This is not a Slight Risk day, not a live watch, and not a U.S. mainland hurricane landfall. NHC reports no tropical cyclones in the Atlantic, eastern Pacific, or central Pacific as of this afternoon. Two MCDs with watch-unlikely tags are not watches. The work, if it verifies, will be scattered: a wind swath through an Indiana or Ohio county, a hail core in northeastern Utah, a flooded wash in Arizona or New Mexico, leftover river water in north-central Missouri.

Looking ahead

SPC Day 2 (Thursday, valid 171200Z–181200Z) currently carries no severe thunderstorm areas. The 1730 UTC Day 2 discussion leaves room for later low-end wind probabilities near the Appalachians and Ohio Valley but kept the threat too marginal for an outlook area in this update. WPC still has a nocturnal Slight flood overlay from Iowa into northern Illinois late tonight, plus lingering Southwest water. The next Storm Tracker update should re-check the 0100 UTC Day 1 outlook and any new watches rather than assuming this afternoon’s Marginal stays the last word.

Sources and how to verify

Primary sources: NOAA Storm Prediction Center Sep 16, 2026 2000 UTC Day 1 Convective Outlook (Chalmers/Weinman, previous Hart/Chalmers); 1730 UTC Day 2 Convective Outlook; current convective watches (none valid; last issued Watch 669); Mesoscale Discussion 2302; Mesoscale Discussion 2303; SPC preliminary storm reports for 20260916 and 20260915; Weather Prediction Center Day 1 Excessive Rainfall Outlook (Kleebauer, 352 AM EDT); National Hurricane Center Tropical Weather Outlooks, September 16, 2026 (no tropical cyclones in Atlantic, eastern Pacific, or central Pacific).

Morning desk: Wednesday, September 16 morning Storm Updates. Prior afternoon: Tuesday, September 15 afternoon Storm Updates.

Check weather.gov for the county warning, spc.noaa.gov for the outlook, watch, MD, and LSRs, and WPC excessive rainfall for the flood overlay.

Informational only — not an official weather warning. Follow local authorities and the National Weather Service. Turn around, don’t drown.

September 16, 2026

Category: Storm Tracker

Northern Fillmore and Mower Counties — Flash Flood Warning

Stay safe tonight

What this means for restoration teams

FEMA & federal assistance

Looking ahead

Sources & how to verify

Southern Fillmore County — Flash Flood Warning

Stay safe tonight

What this means for restoration teams

FEMA & federal assistance

Looking ahead

Sources & how to verify

Waseca and Surrounding Counties — Flash Flood Warning

Stay safe tonight

What this means for restoration teams

FEMA & federal assistance

Looking ahead

Sources & how to verify

What is live this afternoon

Hotspot 1 — Carolina Piedmont into northern Georgia

Hotspot 2 — Upper Mississippi Valley water

Hotspot 3 — Intermountain West and central High Plains

Just hit

Pulse table

What this means for restoration teams

What this is not

Looking ahead

Sources and how to verify

What is live this morning

Overnight into this morning

Hotspot 1 — Carolinas into northern Georgia

Hotspot 2 — Iowa and the Upper Mississippi Valley

Hotspot 3 — Intermountain West and central High Plains

Just hit

Pulse table

What this means for restoration teams

What this is not

Looking ahead

Sources and how to verify

Rexburg area — Flash Flood Warning

Stay safe tonight

What this means for restoration teams

Local emergency contacts

FEMA and federal assistance

Looking ahead

Sources and how to verify

Idaho Falls area — Flash Flood Warning

Stay safe tonight

What this means for restoration teams

Local emergency contacts

FEMA and federal assistance

Looking ahead

Sources and how to verify

What is live this afternoon

Hotspot 1 — Southern and central Idaho into northern Utah

Hotspot 2 — Dakotas water corridor and the High Plains wind overlay

Hotspot 3 — Southwest terrain leftover plus Ohio just-hit

Just hit

Pulse table

What this means for restoration teams

What this is not

Looking ahead

Sources and how to verify

What is live this morning

Hotspot 1 — Utah, Idaho, and southwest Montana

Hotspot 2 — Central High Plains and the Dakotas water corridor

Hotspot 3 — Southwest terrain leftover plus Ohio just-hit

Just hit

Pulse table

What this means for restoration teams

What this is not

Looking ahead

Sources and how to verify

What is live this afternoon

Hotspot 1 — East-central Indiana into central and eastern Ohio

Hotspot 2 — Southern and central Arizona, Sacramento Mountains of New Mexico

Hotspot 3 — Northeastern Utah into far northwest Colorado

Just hit

Pulse table