Flash Flood Warning 148, NWS Tucson, AZ

078 
WGUS55 KTWC 220110
FFWTWC
AZC019-220315-
/O.EXT.KTWC.FF.W.0148.000000T0000Z-260822T0315Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Tucson AZ
610 PM MST Fri Aug 21 2026

The National Weather Service in Tucson has extended the

* Flash Flood Warning for...
  Central Pima County in southeastern Arizona...

* Until 815 PM MST.

* At 610 PM MST, Water levels are slowly receding from the 1 to 3
  inches of rain that fell earlier this afternoon along Highway 286
  at Altar Wash. Flash flooding is likely still ongoing. Additional
  thunderstorms will move across this area through 7 pm.

  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...
  Mainly rural areas of Central Pima County along and near Highway
  286 between Three Points and Arivaca Road.

This includes Route 286 between mile markers 22 and 34.

This includes the following streams and drainages...
  Brown Wash, Fresno Wash, Altar Wash, Cerro Prieto Wash, Saucito
  Wash and Banner Wash.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3177 11144 3186 11138 3193 11138 3193 11140
      3177 11148

FLASH FLOOD...RADAR AND GAUGE INDICATED

$$

Area Forecast Discussion
National Weather Service Tucson AZ
137 PM MST Fri Aug 21 2026

.SYNOPSIS...

Isolated to scattered afternoon and early evening thunderstorms
expected through Saturday, with daily but reduced chances Sunday
into next week. Strong, gusty winds and locally heavy rainfall
will be possible with any thunderstorm. High temperatures will
remain above normal through the coming week.

&&

.DISCUSSION...

A north-south elongated upper level high sits over the Four
Corners and desert southwest today. The orientation of this high
has marginally dried out the atmosphere, as the moisture source
region is more northeasterly than southeasterly. Even so,
adequate moisture remains today for a round of scattered
thunderstorms across areas of southeastern Arizona. Precipitable
water values aren't eye popping (below an inch in Graham-
Greenlee- Cochise counties and 1-1.25 inch further west) and
inverted-V soundings point to a mainly wind threat, however an
isolated flash flooding threat can't be ruled out. Otherwise,
gusty winds of 40-50 mph will be possible with any stronger
thunderstorm, with a very isolated shot at a severe and damaging
wind gust. A similar setup is forecast Saturday afternoon and
early evening where isolated to scattered thunderstorms should
form again.

The upper level ridge will nudge east by the late weekend, which
will take temperatures down a few degrees on Sunday. The current
Extreme Heat Warning goes through Saturday which still looks
valid, then temperatures will "cool" by 2-5 degrees Sunday and
Monday. Guidance is fairly consistent in bringing the upper
level ridge back over the desert southwest by the middle of next
week however, and another heat headline may be needed from at
least Tuesday onwards.

Thunderstorm chances are about 15-30 percent on Saturday, then
a bit lower Sunday into next week. Chances will depend on day to
day mechanisms and the position of the upper high, but any day
can still carry the threat of severe wind and flash flooding as
adequate moisture remains in place.

&&

.AVIATION...Valid through 23/00Z.

Scattered -TSRA mainly through KE77-KTUS-KOLS with isolated
-TSRA near KSAD-KDUG, diminishing by 22/03Z. Gusts of 35-45 kts
 possible with any storm. Otherwise surface winds light and
 terrain driven. Additional thunderstorm development expected
 again Saturday afternoon. Aviation discussion not updated
for TAF amendments.

&&

.FIRE WEATHER...

Isolated to scattered thunderstorms expected Saturday afternoon
with daily but reduced chances going into next week.
Temperatures will remain above normal through the coming week.
Minimum relative humidity values mainly 15-30 percent each day
with light and terrain driven wind.

&&

.TWC WATCHES/WARNINGS/ADVISORIES...
Extreme Heat Warning until 8 PM MST Saturday for AZZ501-502-
504>506-509.

&&

DISCUSSION...Edwards
AVIATION...Edwards
FIRE WEATHER...Edwards

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Preliminary Local Storm Report
National Weather Service Tucson AZ
1201 PM MST Fri Aug 21 2026

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0655 PM     Tstm Wnd Dmg     6 SSW Tucson            32.13N 110.94W
08/19/2026                   Pima               AZ   Local Official

            Damage to parking structures due to strong
            wind gusts.

&&

MJS