Storm Updates: Appalachians–Southeast Marginal + Central Appalachians Flood Slight — Monday, September 21, 2026

This is a live Monday afternoon snapshot of U.S. local-storm activity as of Monday, September 21, 2026. The Storm Prediction Center 2000 UTC Day 1 Convective Outlook holds a Marginal Risk of severe thunderstorms from parts of the Southeast into the central Appalachians and over the Texas South Plains. No convective watches are currently valid. The Weather Prediction Center maintains a Slight Risk of excessive rainfall over portions of the central Appalachians. Scattered severe thunderstorm warnings and flash-flood warnings remain active this afternoon across portions of the Tennessee Valley, Carolinas, Alabama, and West Virginia.

These are county- and ZIP-scale thunderstorms and localized heavy-rain pulses, not a mainland hurricane landfall or organized derecho. Restoration exposure this afternoon and evening is wind-driven tree and roof work, isolated hail, and interior water where cells train or flash-flood warnings verify. Conditions change fast. Verify with the National Weather Service for the specific county or ZIP before you roll.

What is live this afternoon

SPC’s Marginal Risk covers the Southeast into the southern and central Appalachians, with isolated damaging wind gusts of 50–60 mph the primary threat. A second Marginal area sits over the Texas South Plains where isolated large hail and severe gusts remain possible later today. Mesoscale Discussion 2323 (issued 1938 UTC) covers the Texas South Plains into the Permian Basin and notes watch issuance is unlikely; strongest storms may briefly produce large hail up to 1.25 inches and marginally severe wind.

WPC’s Day 1 Excessive Rainfall Outlook keeps a Slight Risk over the central Appalachians (expanded earlier to include more of West Virginia and southwest Virginia). Guidance supports 1–3 inches with locally higher amounts where cells train near a backdoor cold front and shortwave energy. Flash Flood Warnings and Flood Warnings remain active or recently expired across portions of West Virginia, Ohio, and adjacent counties from overnight and early-morning convection.

Hotspot 1 — Central Appalachians and Mid-Atlantic fringe (WPC Slight + SPC Marginal)

This is the dual-threat corridor. Scattered thunderstorms continue along and south of a cold front stretching from southern Virginia west-northwest into northern Kentucky and southwestward. Highest coverage expected from southeast Tennessee and northwest Georgia through northern Alabama into central/southern Mississippi and eastern Louisiana, with additional activity into southwest Virginia and West Virginia. Vertical shear is weak; storm mode is largely multicellular and outflow-dominant, but ample moisture (PW values over 2 inches) supports strong to locally severe gusts and flash flooding on saturated soils.

Cities and counties to watch: Charleston, Parkersburg, and surrounding West Virginia counties; southwest Virginia counties including Giles, Mercer, and Summers; portions of eastern Kentucky and southern Ohio; Chattanooga and Knoxville metro fringes in Tennessee; northern Alabama counties including Madison and Marshall.

Restoration read: wind and water both in play. Stage tarps, generators, and tree crews. Flash-flood warnings mean extraction and drying work may already be on the books by evening. Photograph roofs in remaining daylight only if it is safe.

Hotspot 2 — Texas South Plains and northeast Texas

Isolated to widely scattered storms continue near the intersection of a weak surface trough and cold front across the Texas South Plains into the Permian Basin. MD 2323 flags the potential for brief severe storms capable of large hail and marginally severe wind before dissipation this evening. A secondary area of higher thunderstorm coverage is expected over northeast Texas this afternoon and evening, where water-loaded downbursts capable of damaging wind gusts are possible.

Cities and counties to watch: Lubbock, Midland, and surrounding South Plains counties; portions of northeast Texas near the Red River. Local Severe Thunderstorm Warnings have already fired this afternoon in the region.

Restoration read: hail and wind first. Check vehicle and roof damage reports quickly; these are short-lived cells but can produce ticket-scale damage in a single ZIP.

Hotspot 3 — Southeast scatter (Carolinas, Georgia, Alabama, Mississippi)

Ongoing multicell storms continue to produce local Severe Thunderstorm Warnings with 60 mph wind and small to quarter-size hail. Coverage is highest from southeast Tennessee and northwest Georgia through northern Alabama into central/southern Mississippi and eastern Louisiana. Storms are moving relatively slowly or nearly stationary in places, increasing the local flash-flood and wind-damage potential.

Cities and counties to watch: Chattanooga, Huntsville, Birmingham metro areas; portions of the Carolinas and northern Georgia where warnings have been active this afternoon.

Restoration read: scattered wind and tree damage plus isolated water jobs. Treat each warning county as its own ticket rather than a regional event.

Just hit

Overnight and early-morning convection produced Flash Flood Warnings across portions of West Virginia and southeast Ohio, with residual river and stream rises still ongoing in some gauges. Yesterday’s High Plains activity (eastern Colorado into western Kansas) produced large hail reports up to baseball size and is already in the ticket pipeline for those counties. Local wind damage reports from trees and power lines continue to filter in from the Ohio Valley, Illinois, Missouri, Georgia, Alabama, and the Carolinas. No new U.S. mainland tropical cyclone threat is in the National Hurricane Center outlook at this hour.

Pulse table

What this means for restoration teams

Wind at 50–60 mph is roof, siding, gutter, and tree-on-structure work. Hail on the South Plains is vehicle and roof impact. Heavy rain on the central Appalachians Slight Risk is wet drywall and a 24–48 hour mold clock where flash flooding verifies. Overnight West Virginia and Ohio water is already inside some buildings.

For teams near active warnings: stage before the next cell arrives, not after the first report. 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 regional derecho and not a U.S. mainland hurricane landfall. The work this afternoon and evening, if it verifies, will be scattered: a wind swath through a Tennessee or West Virginia county, a flooded intersection where Appalachian cells train, isolated hail on the South Plains. That is the local-storm pattern this desk should staff.

Looking ahead

Tuesday the front continues to push south and east with another Marginal Risk possible over portions of the Southeast. Residual flooding in the central Appalachians may linger into Tuesday morning. Watch the next Storm Tracker update rather than assuming today’s Marginal and Slight Risk areas are the last line of the week.

Sources and how to verify

Primary sources: NOAA Storm Prediction Center Day 1 Convective Outlook (2000 UTC, September 21, 2026) and Mesoscale Discussion 2323; Weather Prediction Center Day 1 Excessive Rainfall Outlook; National Weather Service warning text for Charleston WV, Blacksburg VA, Huntsville AL, Morristown TN, Lubbock TX, and neighboring offices; SPC Local Storm Reports.

Check weather.gov for the county warning, spc.noaa.gov for the outlook, watches, MDs, and LSRs, and WPC excessive rainfall for the flood overlay. Related desk: Monday morning Storm Updates.

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