Alert archive / Arizona / Flash Flood Warnings in 2026

Flash Flood Warning 149, NWS Tucson, AZ

August 23, 2026Santa Cruz County, Arizona

NWS Tucson, AZ issued this flash flood warning at Aug 23, 2026, 3:40 PM MST for Santa Cruz 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 outline as issued.

The facts

Issued
Aug 23, 2026, 3:40 PM MST (22:40 UTC)
Expired
Aug 23, 2026, 6:32 PM MST
In force
3 hr
Issued by
NWS Tucson, AZ
Area
Storm-based polygon
Flood severity
None

County Santa Cruz County, AZ

The radar

The Tucson radar (KEMX), 22 km from the middle of the area, began a volume at 22:42 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.

Did it verify

Not verified. The Iowa Environmental Mesonet's Cow found no qualifying storm report inside this flash flood warning while it was in force. That is not proof nothing happened: reports are thin where few people live.

Cow counts a report within 15 km of the polygon while the warning was in force: a tornado for a tornado warning; hail of 1 inch or more, a gust of 58 mph or more or wind damage for a severe thunderstorm warning; a flash flood report for a flash flood warning.

The nearest sounding before it

Phoenix, AZ (KPSR), launched 12:00Z, 10.7 hours before the alert went out and 224 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 12:00Z on 2026-08-23Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 73 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 12:00Z on 2026-08-23The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 8 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
73 J/kg
Mixed-layer CIN
-289 J/kg
Mixed-layer LCL
3388 m above ground
0-6 km bulk shear
10 kt
0-1 km storm-relative helicity
8 m²/s²
0-3 km storm-relative helicity
-10 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

940 
WGUS55 KTWC 232240
FFWTWC
AZC023-240145-
/O.NEW.KTWC.FF.W.0149.260823T2240Z-260824T0145Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Tucson AZ
340 PM MST Sun Aug 23 2026

The National Weather Service in Tucson has issued a

* Flash Flood Warning for...
  North Central Santa Cruz County in southeastern Arizona...

* Until 645 PM MST.

* At 340 PM MST, An automated rain gage in Gardner Canyon reported
  1.38 inches of rain in 15 minutes. Flash flooding is ongoing or
  expected to begin shortly, especially along Gardner Canyon Creek
  that impacts Gardner Canyon Road.

  HAZARD...Flash flooding caused by thunderstorms.

  SOURCE...Gauges 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...
  Mainly rural areas of North Central Santa Cruz County.

This includes Route 83 near mile marker 36.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Turn around, don't drown when encountering flooded roads. Most flood
deaths occur in vehicles.

&&

LAT...LON 3173 11063 3167 11074 3170 11082 3173 11081

FLASH FLOOD...GAUGE INDICATED

$$

CWR
1 follow-up statement
150 
WGUS75 KTWC 240132
FFSTWC

Flash Flood Statement
National Weather Service Tucson AZ
632 PM MST Sun Aug 23 2026

AZC023-240142-
/O.CAN.KTWC.FF.W.0149.000000T0000Z-260824T0145Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Santa Cruz AZ-
632 PM MST Sun Aug 23 2026

...FLASH FLOOD WARNING IS CANCELLED FOR NORTH CENTRAL SANTA CRUZ
COUNTY...

Flash flooding is no longer expected to pose a threat. Please
continue to heed remaining road closures.

&&

LAT...LON 3173 11063 3167 11074 3170 11082 3173 11081

$$

CWR

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 Aug 23, 1:43 PM MST, 1 hour 57 minutes earlier.

Area forecast discussion, Aug 23, 1:43 PM MST, 1 hour 57 minutes before
Area Forecast Discussion
National Weather Service Tucson AZ
143 PM MST Sun Aug 23 2026

.SYNOPSIS...
Isolated to scattered afternoon and early evening thunderstorms
through Monday, then reduced storm chances through much of the
remainder of the work week. Strong, gusty winds and locally
heavy rainfall will be possible with any thunderstorm. High
temperatures will remain well above normal through the week
with an Extreme Heat Warning in effect for much of southeast
Arizona.

&&

.DISCUSSION...
The Gulf Surge continues this hour with breezy S/SW winds across
the lower deserts west of Tucson. TDs have eclipse 70 degrees in
far western Pima County with with low to mid 60s for portions of
Pima County (west of Tucson) and Santa Cruz. Across the metro,
TDs are in the 50s to lower 60s. This will set the stage for a
rather robust T'storm day. The question will be where and the
intensity. Looking over the most current MesoA and CAMs, point
to areas across western and central Pima and Santa Cruz Cos. One
or more clusters, potentially forming into a N/NW moving MCS is
possible. Main threats will be strong gusty winds to 60 mph,
especially across central Pima Co where the HREF has a 10% prob
of gusts in excess of 58 mph. Secondary threat will be a
localized flash flood threat where heavier rainfall rates are
realized and any backbuilding/cell mergers in the deeper
moisture from the gulf surge.

For the Tucson Metro, coverage will be more isolated in nature.
Any convection will evolve off the higher terrain and/or OFB
interaction likely from storms south and/or southwest of the
City. Coverage is even less further east where drier air
resides.

The Monsoon still looks to a downturn with much of the region
dry through most of the work week. Best opportunity (10-30%)
daily will be along the International Border and the White Mtns.
By Friday, there could be an expansion in coverage for most of
SEAZ to see at least isolated activity.

Heat remains front and center through the week, with widespread
Major Heatrisk with areas of Extreme. The Extreme Heat Warning
remains in effect through Saturday evening, with most of Santa
Cruz and Cochise Cos starting Tuesday.

&&

.AVIATION /20Z SUNDAY THROUGH 18Z MONDAY/...
Generally FEW-SCT clouds 9-13k ft AGL through the forecast period
with locally BKN clouds between 23/21Z and 24/09Z. Expect isolated
to scattered SHRA/TSRA this afternoon into evening, mainly west of a
KFHU-KSAD line, diminishing by 24/06Z. Currently VCTS for
KTUS/KOLS in the TAFs at this time. Gusts in excess of 40 kts
are expected with the stronger storms. Otherwise surface winds
light and terrain driven. Aviation discussion not updated for
TAF amendments.

&&

.FIRE WEATHER...
Isolated to scattered thunderstorms expected through Monday,
with the exception of along the NM border where mainly dry
conditions are expected. Thereafter, reduced chances for
thunderstorm activity for most of southeast Arizona for the rest
of the work week, though some isolated storms will continue
along the immediate Int'l border and White Mountain region.
Temperatures will remain well above normal through most of the
week with Monday being the coolest day of the period. Drier
conditions will return in the middle of the week with minimum
relative humidity values mainly 10-18 percent in the valleys
and 20-30 percent in the mountains. Winds will generally remain
less than 15 mph and terrain driven through the week.

&&

.TWC WATCHES/WARNINGS/ADVISORIES...
Extreme Heat Warning until 8 PM MST Saturday for AZZ501-502-
504>506-509.
Extreme Heat Warning from 10 AM Tuesday to 8 PM MST Saturday
for AZZ503-507-508.

&&

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The office that day

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

IssuedProductOfficeCountiesLasted
Aug 23, 3:22 PM MSTSevere Thunderstorm WarningTWCPima, Santa Cruz23 min
Aug 23, 4:09 PM MSTSevere Thunderstorm WarningTWCSanta Cruz51 min
Aug 23, 4:53 PM MSTSevere Thunderstorm WarningTWCPima52 min

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.