Arizona–New Mexico Slight Storm Updates

Tropical: None · Severe: Slight · Flood: Moderate

What Changed

Compared with the October 21 afternoon desk pulse table (SPC Slight over much of Arizona into SE Nevada/SW Utah): the latest SPC Day 1 Convective Outlook (0100 UTC October 23 / 6:00 PM PDT October 22, 2026, valid 230100Z–231200Z, issued 0801 PM CDT) holds a SLIGHT RISK of severe thunderstorms from eastern Arizona into western New Mexico. Large hail, damaging winds, and a tornado or two remain possible into the evening. The axis has shifted eastward as the upper trough progresses.
Severe Thunderstorm Watches #691 and #692 issued earlier on October 22 for Arizona have expired (by 1700–1800 UTC). Overnight local storm reports and warnings verified large hail, damaging winds, and flash flooding across Arizona higher terrain, Phoenix metro approaches, and southern Utah canyons. No new convective watches are active as of this desk.
WPC Day 1 Excessive Rainfall Outlook (updated 1601 UTC October 22, valid 16Z Oct 22–12Z Oct 23) introduces a MODERATE RISK over portions of southwest Colorado and southern Utah, with a broad Slight risk remaining across the Southwest including Arizona and western New Mexico. This is an upgrade from the prior Slight-only footprint over the same region. Anomalous moisture and orographic enhancement drive the higher threat.
Subtropical Storm Josephine continues accelerating northeastward away from the United States, forecast to become a powerful extratropical cyclone. No tropical storm or hurricane watches or warnings are in effect on the U.S. coast or Gulf. Tropical Storm Vance remains well south of Mexico in the Eastern Pacific with no U.S. threat.
The restoration ticket remains driven by Arizona/New Mexico severe (hail and wind) plus the new Moderate flood risk over southern Utah and southwest Colorado. Quiet Pulse is closed.

Live Status

As of this Thursday evening / Friday morning desk, October 23, 2026 (approximately 6:16 PM PDT October 22 / 0116Z October 23), the SPC maintains a Slight risk (Level 2 of 5) from eastern Arizona into western New Mexico through the remainder of the evening. Moderate buoyancy (MLCAPE around 1000 J/kg) and strong deep-layer shear (effective bulk wind difference 50–60 kt) support a mix of supercells and linear clusters. Large hail and severe gusts are the primary hazards; a tornado or two is possible where low-level flow is backed near northwestern New Mexico and southern Colorado terrain. Isolated strong to severe storms continue farther north into the Great Basin with more limited buoyancy.

The flood lane has upgraded to Moderate. WPC Day 1 places a Moderate risk over southwest Colorado (San Juan Mountains) and southern Utah, where prior heavy rainfall has elevated hydrologic sensitivity. Storm totals of 3–4 inches (locally 5+) are forecast, with orographic enhancement and rates periodically reaching 0.5 inch per hour. A broad Slight risk covers the remainder of the Southwest, including Arizona and western New Mexico, where convective rates of 1–2 inches per hour remain possible with training cells. Marginal risks cover portions of central California and southeast Florida.

The tropical lane remains closed for U.S. land impact. Subtropical Storm Josephine is accelerating northeastward away from the Mid-Atlantic, expected to transition to a powerful extratropical cyclone. No coastal watches or warnings are in effect. See the Josephine 2026 storm hub.

Hotspots

Eastern Arizona into western New Mexico: Primary remaining severe threat this evening. Ongoing convection organized into supercells and clusters capable of large hail, damaging winds, and isolated tornadoes as the main band shifts eastward.

Southwest Colorado and southern Utah: Moderate excessive rainfall risk. San Juan Mountains and slot canyons/washes are the focus for significant flash flooding given prior rainfall and continued moisture plume.

Central Arizona and Phoenix metro approaches: Included in the Slight severe and Slight flood envelopes earlier in the day; residual risk for heavy rain and isolated strong storms as the axis moves east.

Just-Hit

Local storm reports and NWS warnings through October 22 document large hail (quarter to golf-ball size and larger), damaging wind gusts to 60+ mph, and flash flooding across Arizona counties including Navajo, Apache, Gila, Maricopa, and Pinal. Flash Flood Warnings have been active on Chinle Creek and Canyon de Chelly National Monument, with river gauges indicating life-threatening flooding in places. Severe Thunderstorm Warnings covered areas near Show Low, Globe, and Superior. Southern Utah canyons between Zion and Bryce saw flash flooding. No new major river flooding is reported beyond these local impacts, but the Moderate risk supports continued high runoff potential overnight into early October 23.

Pulse Table

Lane	Status	Notes (as of ~6:16 PM PDT Oct 22 / 0116Z Oct 23 2026)
Tropical	None	Subtropical Storm Josephine accelerating NE away from the U.S., transitioning to extratropical. No coastal watches or warnings. TS Vance far south of Mexico.
Severe	Slight	SPC Day 1 (0100Z Oct 23): Slight from eastern AZ into western NM for large hail, damaging winds, isolated tornado. Prior watches expired. Marginal farther north into Great Basin.
Flood	Moderate	WPC Day 1 Moderate over SW Colorado and southern Utah; Slight across Southwest including AZ/western NM. Orographic 3–5″ totals possible in San Juans. Prior Flash Flood Warnings verified.

Rising Queries

Trends unreachable

Restoration Read

Dominant ticket is Arizona/New Mexico severe (Slight risk with verified hail and wind damage from prior rounds) plus the upgraded Moderate flood risk over southern Utah and southwest Colorado. Phoenix metro and central Arizona face residual heavy rain and isolated strong storms as the axis shifts east. Monitor official sources for active Flash Flood and Severe Thunderstorm Warnings. The October 21 afternoon desk is linked under Sources.

What This Is Not

This is not an official forecast or warning. It is a desk summary of public products from the SPC, WPC, NWS, and NHC. A Moderate excessive rainfall risk is in effect over portions of southwest Colorado and southern Utah; Slight severe risk covers eastern Arizona into western New Mexico. No U.S. tropical watches or warnings are active.

Looking Ahead

Friday: SPC Day 2 carries a Marginal risk. WPC Day 2 continues excessive rainfall potential over portions of the West as the trough progresses. Josephine continues as a powerful extratropical system well offshore. The primary severe and flood axes continue shifting eastward overnight into early Friday, with decreasing coverage as buoyancy wanes.

Sources

Informational only — not an official warning. Always confirm with the latest official forecasts from weather.gov, spc.noaa.gov, wpc.ncep.noaa.gov, and nhc.noaa.gov. Turn around, don’t drown.