Alert archive / Arizona / Flash Flood Warnings in 2026

Flash Flood Warning 137, NWS Tucson, AZ

August 13, 2026Pima County, Arizona

NWS Tucson, AZ issued this flash flood warning at Aug 13, 2026, 4:38 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 outline as issued.

The facts

Issued: Aug 13, 2026, 4:38 PM MST (23:38 UTC)
Expired: Aug 13, 2026, 7:30 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), 33 km from the middle of the area, began a volume at 23:42 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, 11.6 hours before the alert went out and 194 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 70 J/kg
Mixed-layer CIN: -100 J/kg
Mixed-layer LCL: 1318 m above ground
0-6 km bulk shear: 21 kt
0-1 km storm-relative helicity: 64 m²/s²
0-3 km storm-relative helicity: 55 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted.

876 
WGUS55 KTWC 132338
FFWTWC
AZC019-140230-
/O.NEW.KTWC.FF.W.0137.260813T2338Z-260814T0230Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Tucson AZ
438 PM MST Thu Aug 13 2026

The National Weather Service in Tucson has issued a

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

* Until 730 PM MST.

* At 438 PM MST, Doppler radar indicated thunderstorms producing
  heavy rain across the warned area. Between 0.5 and 1.5 inches of
  rain have fallen. Additional rainfall amounts up to 1 inch are
  possible in the warned area. Flash flooding is ongoing or expected
  to begin shortly.

  HAZARD...Flash flooding caused by thunderstorms.

  SOURCE...Radar indicated.

  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, East Sahuarita and Summit.

This includes Interstate 19 between mile markers 34 and 51.

-This includes the following streams and drainages...
Box Canyon Wash, Old Junction Wash, Demetrie Wash and Santa Cruz
River. Showers and storms are developing and training over the same
locations. This could persist for the next couple hours with an
increasing flash flood risk.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

In hilly terrain there are hundreds of low water crossings which are
potentially dangerous in heavy rain. Do not attempt to cross flooded
roads. Find an alternate route.

&&

LAT...LON 3205 11095 3201 11103 3197 11106 3195 11114
      3183 11117 3179 11113 3177 11104 3174 11094
      3176 11083 3185 11078 3192 11078 3194 11092

FLASH FLOOD...RADAR INDICATED

$$

JRM

2 follow-up statements

742 
WGUS75 KTWC 140055
FFSTWC

Flash Flood Statement
National Weather Service Tucson AZ
555 PM MST Thu Aug 13 2026

AZC019-140230-
/O.CON.KTWC.FF.W.0137.000000T0000Z-260814T0230Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Pima AZ-
555 PM MST Thu Aug 13 2026

...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 730 PM MST THIS
EVENING FOR EAST CENTRAL PIMA COUNTY...

At 555 PM MST, Doppler radar indicated earlier heavy rain has largely
ended, but localized showers and storms remain between Green Valley
and Amado. Between 0.5 and 1.5 inches of rain have fallen. Additional
rainfall amounts of 0.2 to 0.4 inches are possible in the warned
area. Flash flooding is ongoing or expected to begin shortly.

HAZARD...Flash flooding caused by thunderstorms.

SOURCE...Radar indicated.

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, East Sahuarita and Summit.

This includes Interstate 19 between mile markers 34 and 49.

This includes the following streams and drainages...
  Box Canyon Wash, Demetrie Wash and Santa Cruz River.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

In hilly terrain there are hundreds of low water crossings which are
potentially dangerous in heavy rain. Do not attempt to cross flooded
roads. Find an alternate route.

&&

LAT...LON 3197 11106 3198 11100 3203 11098 3205 11095
      3194 11094 3188 11080 3185 11078 3178 11086
      3176 11092 3177 11104 3181 11108 3184 11110
      3191 11109

FLASH FLOOD...RADAR INDICATED

$$

JRM

662 
WGUS75 KTWC 140224
FFSTWC

Flash Flood Statement
National Weather Service Tucson AZ
724 PM MST Thu Aug 13 2026

AZC019-140234-
/O.EXP.KTWC.FF.W.0137.000000T0000Z-260814T0230Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Pima AZ-
724 PM MST Thu Aug 13 2026

...FLASH FLOOD WARNING WILL EXPIRE AT 730 PM MST THIS EVENING FOR
EAST CENTRAL PIMA COUNTY...

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

&&

LAT...LON 3197 11106 3198 11100 3203 11098 3205 11095
      3194 11094 3188 11080 3185 11078 3178 11086
      3176 11092 3177 11104 3181 11108 3184 11110
      3191 11109

$$

JRM

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 13, 1:15 PM MST, 3 hours 23 minutes earlier.

Area forecast discussion, Aug 13, 1:15 PM MST, 3 hours 23 minutes before

Area Forecast Discussion
National Weather Service Tucson AZ
115 PM MST Thu Aug 13 2026

.SYNOPSIS...

Today scattered showers and thunderstorms with some of the
storms capable to produce brief heavy rain. Drier and hotter
conditions return this weekend with an Extreme Heat Watch issued
for Monday though Wednesday.

&&

.DISCUSSION...

Where there was clearing this morning showers and thunderstorms
have developed. Substantial moisture remains in place with
satellite derived PWATs around 1.3" to 1.7", higher values Tucson
westward and surface dewpoints in the upper 50s to low 60s.
The Weather Prediction Center (WPC) has areas Tucson eastward
in Slight risk for excessive rainfall. The 12Z HREF highlights
this area with a 10-50% chance for greater than 1 inch of
rainfall, in a 3 hour period, with pockets of up to 2 inches
possible. While there is suitable instability in place, the main
concern today is flash flooding. There is a chance a storm or
two could produce gusty to strong outflow winds with small hail.
Rainfall overnight and over the past several days has made the
area highly susceptible for flash flooding thus any more rain
that falls will have a much higher chance to cause impacts.
Temperatures today will be 5 to 7 degrees below normal.

Dry air begins to move into the area beginning tomorrow moving
in across the area through weekend. Enough moisture will be in
place for daily chances for afternoon into the evening showers
and thunderstorms though they will mainly be to the south and
east of Tucson. During this time temperatures begin to gradually
rise eventually pushing high temperatures 5 to 7 degrees above
normal. This will bring HeatRisk to Major for the lower deserts
and Extreme for some locales including Tucson and Safford by
Monday. Due to this, an Extreme Heat Watch has been issued
starting Monday through Wednesday for a majority of Pima county,
Pinal county, and southern Graham and Greenlee counties.
Temperatures begin to cool Thursday and chances for daily
thunderstorms begin to increase.

&&

.AVIATION... Valid through 15/00Z.

Area of showers and isolated thunderstorms with ceiling bases
7-11k ft AGL from KTUS east with gusty erratic winds of 30-40
kts possible with any thunderstorm now through 14/05Z. Outside
of storms SFC winds WLY/NWLY at 8-12 kts with ocnl gusts to 20
kts. SFC winds light and terrain driven between 14/06Z and
14/16Z. Aviation discussion not updated for TAF amendments.

&&

.FIRE WEATHER...

Scattered showers and thunderstorms today with the main concern
being heavy rainfall leading to flash flooding, gusty outflow
winds, and lightning. This system will then draw in drier air
Friday into the weekend resulting in a low- grade monsoon
pattern with chance of storms each day mainly south and east of
Tucson. A little more active monsoon pattern sets in early next
week. Minimum relative humidity will be 20-40 percent today
lowering to around 15-30 percent thereafter. Temperatures will
be below normal today, then warm up again to above normal this.
Outside of thunderstorms, winds terrain driven to around 10 mph
with occasional afternoon gusts to 20 mph.

&&

.TWC WATCHES/WARNINGS/ADVISORIES...
Extreme Heat Watch from Monday morning through Wednesday
evening for AZZ501-502-504>506-509.

&&

Malarkey

Visit us on Facebook, X, YouTube, and at weather.gov/Tucson

In the hours before

Local storm report, Aug 13, 1:44 PM MST, 2 hours 54 minutes before

Preliminary Local Storm Report
National Weather Service Tucson AZ
144 PM MST Thu Aug 13 2026

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

0611 AM     Flash Flood      Duncan                  32.74N 109.09W
08/13/2026                   Greenlee           AZ   Law Enforcement

            Delayed report. Video on social media
            showing rushing water over roadways. Water
            took out sections of roadway and exposed
            under roadway culverts. Carlisle Rd and
            Campbell St closed.

&&

JVT

Local storm report, Aug 13, 1:47 PM MST, 2 hours 51 minutes before

Preliminary Local Storm Report
National Weather Service Tucson AZ
147 PM MST Thu Aug 13 2026

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

0611 AM     Flash Flood      1 SW Duncan             32.73N 109.10W
08/13/2026                   Greenlee           AZ   Law Enforcement

            Delayed Report. Video showing running water
            with tree debris on bridge along Fairgrounds
            Rd. Water not overtopping bridge as of
            video. Closed roadway.

&&

JVT

Local storm report, Aug 13, 1:58 PM MST, 2 hours 40 minutes before

Preliminary Local Storm Report
National Weather Service Tucson AZ
158 PM MST Thu Aug 13 2026

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

0502 AM     Flash Flood      3 WSW Marana            32.40N 111.22W
08/13/2026                   Pima               AZ   Fire Dept/Rescue

            Delayed Report. Water rescue at West Avra
            Valley Rd and North Sandario Rd. 5
            individuals rescued from vehicle with no
            injuries.

&&

JVT

Local storm report, Aug 13, 2:15 PM MST, 2 hours 23 minutes before

Preliminary Local Storm Report
National Weather Service Tucson AZ
215 PM MST Thu Aug 13 2026

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

0200 PM     Flash Flood      1 WNW Sierra Vista      31.57N 110.35W
08/13/2026                   Cochise            AZ   Other Federal

            Arizona St and Hunt Rd intersection flooded
            with rushing water overspilling ditch.

&&

JVT

The office that day

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

Issued	Product	Office	Counties	Lasted
Aug 12, 9:58 PM MST	Areal Flood Advisory	TWC	Pima	28 hr
Aug 12, 11:40 PM MST	Areal Flood Advisory	TWC	Pima, Pinal	2 hr
Aug 13, 12:28 AM MST	Flash Flood Warning	TWC	Pinal	3 hr
Aug 13, 1:49 AM MST	Areal Flood Advisory	TWC	Pima	3 hr
Aug 13, 3:20 AM MST	Flash Flood Warning Considerable damage threat	TWC	Pima	3 hr
Aug 13, 8:56 AM MST	Areal Flood Advisory	TWC	Pima	6 hr
Aug 13, 11:19 AM MST	Extreme Heat Watch	TWC	Graham, Greenlee, Pima, Pinal	46 hr
Aug 13, 12:35 PM MST	Flash Flood Warning	TWC	Cochise	3 hr
Aug 13, 1:00 PM MST	Flash Flood Warning	TWC	Graham	3 hr
Aug 13, 1:37 PM MST	Flash Flood Warning	TWC	Cochise	5 hr
Aug 13, 2:11 PM MST	Severe Thunderstorm Warning	TWC	Cochise	49 min
Aug 13, 2:45 PM MST	Areal Flood Advisory	TWC	Santa Cruz	3 hr
Aug 13, 2:47 PM MST	Areal Flood Advisory	TWC	Pima, Santa Cruz	3 hr

Nearby

Flash Flood Warnings in Arizona, 2026 Every 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.