Flash Flood Warning 176, NWS Tucson, AZ

631 
WGUS75 KTWC 022135
FFSTWC

Flash Flood Statement
National Weather Service Tucson AZ
235 PM MST Wed Sep 2 2026

AZC019-022330-
/O.CON.KTWC.FF.W.0176.000000T0000Z-260902T2330Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Pima AZ-
235 PM MST Wed Sep 2 2026

...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 430 PM MST THIS
AFTERNOON FOR EAST CENTRAL PIMA COUNTY...

At 235 PM MST, Doppler radar and automated rain gauges indicated
thunderstorms had produced heavy rain across the warned area,
especially with  thunderstorms near Sierrita mine west of Green
Valley where between 1 and 2.5 inches of rain have fallen. Flash
flooding is ongoing or expected to begin shortly.

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...
  Sahuarita, Green Valley and East Sahuarita.

This includes Interstate 19 between mile markers 38 and 47.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

Be aware of your surroundings and do not drive on flooded roads.

&&

LAT...LON 3181 11109 3185 11092 3193 11092 3199 11103
      3200 11118 3191 11120 3184 11118 3182 11114

FLASH FLOOD...RADAR AND GAUGE INDICATED

$$

EDWARDS

642 
WGUS75 KTWC 022328
FFSTWC

Flash Flood Statement
National Weather Service Tucson AZ
428 PM MST Wed Sep 2 2026

AZC019-022338-
/O.EXP.KTWC.FF.W.0176.000000T0000Z-260902T2330Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Pima AZ-
428 PM MST Wed Sep 2 2026

...FLASH FLOOD WARNING WILL EXPIRE AT 430 PM MST THIS AFTERNOON FOR
EAST CENTRAL PIMA COUNTY...

The heavy rain has ended in the Green Valley area. Flooding is no
longer expected to pose a threat. Please continue to heed remaining
road closures.

&&

LAT...LON 3181 11109 3185 11092 3193 11092 3199 11103
      3200 11118 3191 11120 3184 11118 3182 11114

$$

EDWARDS

Area Forecast Discussion
National Weather Service Tucson AZ
1004 AM MST Wed Sep 2 2026

.SYNOPSIS...Little more storm activity today compared to
yesterday, especially south of Tucson. Thursday into the
weekend tropical moisture moves in leading to a further increase
in storm coverage and chances with the main threat being heavy
rainfall. High temperature will will fluctuate between normal
and a few degrees below normal.

&&

.UPDATE...Mostly sunny skies this morning across southeast Arizona
with towering cumulus over the higher terrain of southeast Arizona.
Plenty of lower level moisture with surface dewpoints ranging from
the low 60s eastern areas to mid 60s to lower 70s from Tucson
westward. PWAT values are around 1.1 inches east of Tucson to around
1.3 to 1.4 inches from Tucson westward. Given the higher lower level
moisture, convection will get off to an earlier start today from
late morning into the early afternoon. Main focus today for greater
coverage of storms (40 to 70 percent chances) will be across Santa
Cruz/south central Pima County, reaching northward into eastern Pima
County (Tucson Metro) and then eastward into SW Cochise County.
Primary threat will be locally heavy rainfall with isolated flash
flooding with secondary wind threat with gusts up to around 45 MPH.
See previous discussion below for additional information.

&&

.DISCUSSION...Skies are clearing across the CWA with just some
mid-level cloud cover east of Tucson. Aloft we are in a
transitional monsoon pattern with the ridge well to the east and
a closed low over the Pacific Northwest. There has been some
reduction in moisture over the past day, but PWATs are still
around normal. CAMs show a little more thunderstorm activity
today compared to Tuesday with storm chances extending north
into Tucson and southern Pinal County. But greatest coverage
and chances will still be south of Tucson. The 02/00Z HREF shows
a 20-50 percent chance for 1"-1.5" hourly rainfall rates from
Sells to Sierra Vista this afternoon and evening. This could
lead to isolated areas of flash flooding with a secondary threat
of strong gusty winds to 45 mph. Initial storms could form as
early as noon then continue an hour or two after sunset with
general motion to the north northeast.

Down in the tropics, tropical storm Marie is centered about 450
miles south of the southern tip of Baja moving northwestward. It
is forecasted to become a hurricane later this morning. As it
continues its northwestward track tropical moisture will begin
to be advected northward Thursday into the weekend. PWATs will
likely range from 1.4" near the AZ/NM border to 1.8" in western
Pima County. For Thursday this means expanded storm coverage
northward with scattered convection over most of the CWA from
central Pima County eastward. According to the HREF the heaviest
rainfall threat will be from Tucson southward. The main threat
again will be heavy rainfall leading to flash flooding.

The tropical moisture sticks around through at least the
first part of next week, which will lead to daily afternoon and
evening thunderstorms capable of heavy rainfall. Expect area
washes and rivers to be running by Friday into the weekend,
especially south of Tucson where soils are already fairly
saturated. Aloft the closed low remains over the Pacific
Northwest through Monday, then begins to move inland thereafter.
However ensembles bring another trough in right behind, so
expect Arizona to stay in a transitional monsoon pattern into
next week.

Over the next week high temperatures will fluctuate between
normal and a few degrees below normal.

&&

.AVIATION...Valid through 03/12Z.
Expect SCT-BKN clouds 8-12k ft AGL late this morning into the
evening. TSRA coverage will likely increase compared to
yesterday with isolated to scattered TSRA from Tucson south and
eastward starting as early as 02/20Z and continuing through
03/04Z. KOLS will have the best chances to be impacted by a
storm. Near thunderstorms expect heavy rainfall and gusty winds
to 35 kts. Otherwise winds will be west northwest 5-10 kts this
afternoon and evening, and light and terrain driven at other
times. Aviation discussion not updated for TAF amendments.

&&

.FIRE WEATHER...Expect isolated to scattered storms today
mainly from Tucson south and eastward. Storm chances and
coverage then increase Thursday into the weekend as tropical
moisture moves in. Heavy rainfall leading to flash flooding will
be the main threat. Temperatures will be around normal to a few
degrees below normal today into early next week. Minimum
relative humidity values mainly 20 to 45 percent in the valleys
and 30 to 60 percent in the mountains over the next week. Winds
will generally remain less than 15 mph and terrain driven
through the week.

&&

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

&&

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