Alert archive / Arizona / Flash Flood Warnings in 2026

Flash Flood Warning 193, NWS Tucson, AZ

September 11, 2026Pima County, Arizona

NWS Tucson, AZ issued this flash flood warning at Sep 11, 2026, 6:31 PM MST for Pima County, Arizona. It was in force for 3 hr. No storm report in the archive falls inside the area while it was in force.

The area

The counties it named.

The facts

Issued
Sep 11, 2026, 6:31 PM MST (01:31 UTC)
Expired
Sep 11, 2026, 9:30 PM MST
In force
3 hr
Issued by
NWS Tucson, AZ
Area
Storm-based polygon
Flood severity
None

County Pima County, AZ

The radar

The Tucson radar (KEMX), 112 km from the middle of the area, began a volume at 01:35 UTC, the scan nearest the moment this went out.

Open the radar archive at this moment

The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.

The nearest sounding before it

Phoenix, AZ (KPSR), launched 00:00Z, 1.5 hours before the alert went out and 149 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.

Skew-T log-pSkew-T log-p diagram, Phoenix, AZ at 00:00Z on 2026-09-12Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1071 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Phoenix, AZ at 00:00Z on 2026-09-12The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 13 square meters per square second.1939Sfc1 km3 km6 km9 kmRMLM
The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.
Mixed-layer CAPE
1071 J/kg
Mixed-layer CIN
-78 J/kg
Mixed-layer LCL
2348 m above ground
0-6 km bulk shear
5 kt
0-1 km storm-relative helicity
13 m²/s²
0-3 km storm-relative helicity
12 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

What forecasters said that day

The local office's own words before this flash flood warning went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS Tucson, AZ wrote its last area forecast discussion before this flash flood warning went out at Sep 11, 1:23 PM MST, 5 hours 8 minutes earlier. Its key messages:

  • -Isolated to scattered showers and thunderstorms this afternoon mainly south and east of Tucson capable of producing potentially heavy rainfall. -Slight Risk (Level 2 of 4) today for excessive rainfall that may lead to localized instances of flash flooding in flood prone areas. Sensitive low water crossings may become impassible. -Above normal moisture for mid September continues over the weekend into early next week resulting in continued chances for showers and storms and a Marginal Risk (Level 1 of 4) for excessive rainfall.
Area forecast discussion, Sep 11, 1:23 PM MST, 5 hours 8 minutes before
Area Forecast Discussion
National Weather Service Tucson AZ
123 PM MST Fri Sep 11 2026

.SYNOPSIS...A more active day is forecast across southeast Arizona
today with isolated to scattered showers and thunderstorms. Main
threat from storms today will be heavy rain and localized flash
flooding, especially across Santa Cruz county and southwest Cochise
county. A more typical isolated to scattered coverage of storms is
forecast this weekend into next week. Daily high temperatures will
fluctuate between near normal and a few degrees below normal.

&&

.KEY MESSAGES...

-Isolated to scattered showers and thunderstorms this afternoon
mainly south and east of Tucson capable of producing potentially
heavy rainfall.

-Slight Risk (Level 2 of 4) today for excessive rainfall that may
lead to localized instances of flash flooding in flood prone areas.
Sensitive low water crossings may become impassible.

-Above normal moisture for mid September continues over the weekend
into early next week resulting in continued chances for showers and
storms and a Marginal Risk (Level 1 of 4) for excessive rainfall.

&&

.DISCUSSION...Storms started forming early over high terrain areas
including the Huachuca and White Mountains around 11 am MST which
was a bit sooner than convective allowing models suggested.
Additional storm activity is anticipated to continue this afternoon
and evening with the strongest activity mainly focused south and
east of Tucson. The primary concerns with storms this afternoon
continues to be heavy rainfall (rates 1.0 to 2.5 inches per hour)
and frequent lightning. However, gusty and erratic outflow winds to
around 45 mph cannot be ruled out with the strongest storms as well.
Heavy rainfall may result in isolated instances of flash flooding,
especially across Santa Cruz County, southwest Cochise County, and
far southeast Pima County. Portions of eastern Santa Cruz county and
SW Cochise county has seen heavy rain over the past 72 hours, so the
soils are wet, and the San Pedro has had some increased flow several
days ago making them more susceptible to saturation this afternoon.
Flowing water can be expected in normally dry washes. Sensitive low
water crossings may become impassible with swift moving water.
Remember to remain alert, avoid driving through flooded roads, and
obey road closures.

The extent of showers and storms tomorrow will largely depend on
how the evolution of storm activity this afternoon and evening.
But even if we see less coverage of storms tomorrow, sufficient
moisture in place could again be supportive of heavy rainfall.
The 11/12Z HREF depicts a slight chance (10-30%) for heavy rain
exceeding 2 inches in a 3 hour period across Santa Cruz County
and southeast portions of Pima County.

Sunday through Thursday monsoonal moisture continues to remain in
place daily chances (20-50%) for showers and storms. Otherwise, high
temperatures will remain near normal through Monday afternoon before
we cool off and highs sag slightly below normal.

&&

.AVIATION...Valid thru 13/00Z.
SCT-BKN 6k-9k ft AGL. ISOLD to SCT SHRA/TSRA mainly S and E of KTUS
thru 12/02Z and again aft 12/21Z. Isold VSBY 1-3 miles nr TS. Lclzd
TS outflow winds of 30-40 kts. Otrw, SFC winds WLY/NWLY at 6-10 kts
thru 12/04Z and again aft 12/17Z. At other times, SFC winds will
be terrain driven and less than 10 kts. Aviation discussion not
updated for TAF amendments.

&&

.FIRE WEATHER...Scattered showers and thunderstorms today. A
more typical isolated to scattered coverage of storms is forecast
this weekend into next week. High temperatures will will fluctuate
between near normal and a few degrees below normal. Min RH values
mainly 20 to 45 percent in the valleys and 35 to 65 percent in the
mountains over the next week. RH recoveries will continue to be
excellent overnight. Winds will generally remain less than 15 mph
and terrain driven. Gusty and erratic winds will accompany
thunderstorms.

&&

.TWC WATCHES/WARNINGS/ADVISORIES...None.

&&

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The office that day

Everything else NWS Tucson, AZ issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Sep 11, 5:18 PM MSTAreal Flood AdvisoryTWCCochise3 hr
Sep 11, 5:30 PM MSTAreal Flood AdvisoryTWCPima2 hr
Sep 11, 6:24 PM MSTSevere Thunderstorm WarningTWCCochise44 min
Sep 11, 7:01 PM MSTFlash Flood WarningTWCPima119 min
Sep 11, 7:03 PM MSTAreal Flood AdvisoryTWCPinal117 min
Sep 11, 7:07 PM MSTAreal Flood AdvisoryTWCCochise3 hr
Sep 11, 8:41 PM MSTAreal Flood AdvisoryTWCCochise, Graham3 hr
Sep 11, 9:20 PM MSTFlash Flood WarningTWCCochise, Graham3 hr
Sep 12, 11:38 AM MSTAreal Flood AdvisoryTWCPima, Pinal3 hr
Sep 12, 11:43 AM MSTAreal Flood AdvisoryTWCCochise3 hr
Sep 12, 12:10 PM MSTFlash Flood WarningTWCPima3 hr
Sep 12, 12:16 PM MSTSevere Thunderstorm WarningTWCCochise, Pima, Santa Cruz20 min
Sep 12, 12:37 PM MSTSevere Thunderstorm WarningTWCPima38 min
Sep 12, 12:44 PM MSTSevere Thunderstorm WarningTWCPima46 min
Sep 12, 12:52 PM MSTFlash Flood WarningTWCPima3 hr
Sep 12, 1:06 PM MSTSevere Thunderstorm WarningTWCPima, Santa Cruz39 min
Sep 12, 1:18 PM MSTSevere Thunderstorm WarningTWCPima29 min
Sep 12, 1:21 PM MSTFlash Flood WarningTWCPima3 hr
Sep 12, 1:31 PM MSTFlash Flood WarningTWCPima, Santa Cruz3 hr
Sep 12, 1:44 PM MSTSevere Thunderstorm WarningTWCSanta Cruz46 min
Sep 12, 1:50 PM MSTSevere Thunderstorm WarningTWCPima40 min
Sep 12, 2:01 PM MSTFlash Flood WarningTWCSanta Cruz3 hr
Sep 12, 2:28 PM MSTFlash Flood WarningTWCPima3 hr
Sep 12, 2:45 PM MSTSevere Thunderstorm WarningTWCSanta Cruz19 min
Sep 12, 3:06 PM MSTAreal Flood AdvisoryTWCPima3 hr

Nearby

Flash Flood Warnings in Arizona, 2026Every flash flood warning in 2026

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.