Alert archive / Arizona / Flash Flood Warnings in 2026

Flash Flood Warning 55, NWS Tucson, AZ

July 17, 2026Pima County, Arizona

NWS Tucson, AZ issued this flash flood warning at Jul 17, 2026, 1:51 PM MST for Pima County, Arizona. It was in force for 2 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
Jul 17, 2026, 1:51 PM MST (20:51 UTC)
Expired
Jul 17, 2026, 4:15 PM MST
In force
2 hr
Issued by
NWS Tucson, AZ
Area
Storm-based polygon
Flood severity
None

County Pima County, AZ

The radar

The Tucson radar (KEMX), 29 km from the middle of the area, began a volume at 20:50 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, 8.9 hours before the alert went out and 199 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 2026-07-17Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 57 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 2026-07-17The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 22 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
57 J/kg
Mixed-layer CIN
-106 J/kg
Mixed-layer LCL
1188 m above ground
0-6 km bulk shear
9 kt
0-1 km storm-relative helicity
22 m²/s²
0-3 km storm-relative helicity
59 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

097 
WGUS55 KTWC 172051
FFWTWC
AZC019-172315-
/O.NEW.KTWC.FF.W.0055.260717T2051Z-260717T2315Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Tucson AZ
151 PM MST Fri Jul 17 2026

The National Weather Service in Tucson has issued a

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

* Until 415 PM MST.

* At 151 PM MST, Doppler radar indicated thunderstorms producing
  heavy rain across the warned area, especially around Green Valley.
  Between 1 and 1.5 inches of rain have fallen in portions of Green
  Valley. Additional rainfall amounts of 0.5 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, Corona De Tucson and East Sahuarita.

This includes Interstate 19 between mile markers 33 and 47.

This includes the following Flash Flood Prone Locations...
Sahuarita Rd west of Wilmot Rd.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3199 11094 3188 11116 3176 11107 3175 11100
      3176 11090 3183 11078 3192 11077 3197 11082

FLASH FLOOD...RADAR INDICATED

$$

GEL
2 follow-up statements
934 
WGUS75 KTWC 172147
FFSTWC

Flash Flood Statement
National Weather Service Tucson AZ
247 PM MST Fri Jul 17 2026

AZC019-172315-
/O.CON.KTWC.FF.W.0055.000000T0000Z-260717T2315Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Pima AZ-
247 PM MST Fri Jul 17 2026

...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 415 PM MST THIS
AFTERNOON FOR EAST CENTRAL PIMA COUNTY...

At 247 PM MST, Doppler radar indicated thunderstorms producing heavy
rain across the warned area. Between 1 and 2 inches of rain have
fallen between Green Valley and Corona De Tucson Flooding impacts
will continue, but limited additional rainfall is expected. 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, Corona De Tucson and East Sahuarita.

This includes Interstate 19 between mile markers 33 and 47.

This includes the following Flash Flood Prone Locations...
Sahuarita Rd west of Wilmot Rd.

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

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3199 11094 3188 11116 3176 11107 3175 11100
      3176 11090 3183 11078 3192 11077 3197 11082

FLASH FLOOD...RADAR INDICATED

$$

GEL
438 
WGUS75 KTWC 172315
FFSTWC

Flash Flood Statement
National Weather Service Tucson AZ
415 PM MST Fri Jul 17 2026

AZC019-172325-
/O.EXP.KTWC.FF.W.0055.000000T0000Z-260717T2315Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Pima AZ-
415 PM MST Fri Jul 17 2026

...FLASH FLOOD WARNING HAS EXPIRED FOR EAST CENTRAL PIMA COUNTY...

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

&&

LAT...LON 3199 11094 3188 11116 3176 11107 3175 11100
      3176 11090 3183 11078 3192 11077 3197 11082

$$

GEL

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 Jul 17, 9:30 AM MST, 4 hours 21 minutes earlier.

Area forecast discussion, Jul 17, 9:30 AM MST, 4 hours 21 minutes before
Area Forecast Discussion...correction to update section
National Weather Service Tucson AZ
930 AM MST Fri Jul 17 2026

.UPDATE...Considerable cloud cover exits across southeast Arizona
this morning with a persistent area of light to moderate showers
across the northern part of the Tohono O'odham nation where up to a
inch of rain has fallen in the past 3 hours. Ended up issuing a
small stream advisory for that area for a couple hours with washes
likely running. Updated the remainder of the morning forecast to
remove the mention of thunderstorms this morning and reduce PoPs
across the rest of the area. A relatively down day is expected this
afternoon and evening versus yesterday. However there is weak
diffluent flow at 300 mb and with a moist atmosphere in place, the
threat of localized heavy rain and flash flooding still exits with
any thunderstorm that develops, especially for areas that were hit
pretty good yesterday. A quick look at visible imagery also showed
that a weak MCV was developing near Douglas.

&&

.SYNOPSIS...
Scattered showers and thunderstorms will again
impact Southeast Arizona this afternoon and this evening with an
elevated risk of flash flooding, especially across those areas
that received heavy rainfall Thursday. Otherwise, chances for
thunderstorms will continue through the coming week with day to
day variability in location and severity.

&&

.DISCUSSION...
The upper pattern this morning is defined by an
upper-low positioned over the SE corner of New Mexico with an
elongated upper ridge of high pressure at 300 mb across NW
Arizona into Utah and a bit farther north into WY at 500 mb.
Yesterday was quite an active day across Southeast Arizona as
the precipitable water values were moist enough to be in the
90-95 percentile of climatology. What made it active was the
modest diffluence initially at 300 mb across Cochise county
given the proximity of the upper-low to our east, followed up by
a stretching divergence across Santa Cruz into eastern Pima
county as the 300 mb high moved north during the late afternoon
into the evening. The movement of the upper high has assisted in
the MCS that has developed across central Arizona early this
morning.

Past experience has taught me that usually after a big 'active'
day, the atmosphere struggles the following day because it has
been worked over and it is hard to reload. The moisture profile
will look similar today than yesterday, but what is missing is
any form of modest lift via deformation aloft for more widespread
heavy rainfall. However, given the deep moisture in place, it
wont take much for showers and thunderstorms to develop and that
can be problematic on saturated soils from those locations that
received heavy rainfall Thursday. This though is supported by
the 17/00Z HREF probability between 30-50% across ern Pima/Santa
Cruz/SW Cochise for a 3-hour rainfall in excess of an inch
within 25 miles of a point tomorrow afternoon...far less than
the probabilities we saw Thursday. So expect scattered showers
and thunderstorms today across Southeast Arizona, with the
primary threat from the storms being heavy rainfall...which
could lead to isolated flash flooding problems in areas that
received a lot of heavy rainfall yesterday.

The upper-low to the east remains quasi-stationary into the
weekend with a more favorable easterly flow developing as the
upper-ridge consolidated farther north. with the upper-low
eventually moving across Southeast Arizona along the southern
periphery Tuesday. The Monsoon season rolls-on with a ramp-up
in storms this weekend, but especially Tuesday of next week.

&&

.AVIATION /16Z FRIDAY THROUGH 16Z SATURDAY/...
Valid through 18/12Z. SCT-BKN 11-15k ft AGL thru
17/19Z, then SCT-BKN 7-10k ft AGL BKN-OVC 12-15k ft AGL with
scattered showers and thunderstorms with 3-5SM in heavy rain,
mountain obscurations, and erratic strong wind gusts of 30-40
kts possible with any storm. Outside of thunderstorms, surface
winds generally under 10 kts. Aviation discussion not updated
for TAF amendments.

&&

.FIRE WEATHER...
Daily chances for thunderstorms will continue
each afternoon and evening through the next 7 days with day to
day variability. Minimum relative humidity 25-30 percent in the
lower desert locations and above 40 percent in the mountains
this week. Winds this week will remain mainly light and under 15
mph, though strong and erratic winds will be possible with any
thunderstorm.

&&

&&

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

&&

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

In the hours before

Local storm report, Jul 17, 9:29 AM MST, 4 hours 22 minutes before
Preliminary Local Storm Report
National Weather Service Tucson AZ
929 AM MST Fri Jul 17 2026

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

0513 PM     Flash Flood      1 SW Rio Rico           31.47N 110.99W
07/16/2026                   Santa Cruz         AZ   County Official

            *** 2 FATAL ***
            [Delayed report]: 2 deceased individuals
            reported in the Santa Cruz River. Recovery
            ongoing.

&&

KLM
Local storm report, Jul 17, 10:00 AM MST, 3 hours 51 minutes before
Preliminary Local Storm Report
National Weather Service Tucson AZ
1000 AM MST Fri Jul 17 2026

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

0900 AM     Flood            4 S Santa Rosa          32.28N 112.06W
07/17/2026                   Pima               AZ   Emergency Mngr

            Washes running on Route 15.

&&

KLM
Local storm report, Jul 17, 10:16 AM MST, 3 hours 35 minutes before
Preliminary Local Storm Report
National Weather Service Tucson AZ
1016 AM MST Fri Jul 17 2026

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

0535 PM     Flash Flood      14 NW Sells             32.03N 112.07W
07/16/2026                   Pima               AZ   Emergency Mngr

            [Delayed report] Several washes running
            across HWY 86 between mile marker 99-106.

&&

KLM
Local storm report, Jul 17, 10:50 AM MST, 3 hours 1 minute before
Preliminary Local Storm Report
National Weather Service Tucson AZ
1050 AM MST Fri Jul 17 2026

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

0630 PM     Flash Flood      6 ENE Tombstone         31.74N 109.96W
07/16/2026                   Cochise            AZ   Fire Dept/Rescue

            [Delayed report] Wash flowing across Gleeson
            Rd.

0630 PM     Flash Flood      2 WSW Tombstone         31.71N 110.08W
07/16/2026                   Cochise            AZ   Fire Dept/Rescue

            [Delayed report] Wash flowing across
            Charleston Rd.

&&
Local storm report, Jul 17, 11:28 AM MST, 2 hours 23 minutes before
Preliminary Local Storm Report
National Weather Service Tucson AZ
1128 AM MST Fri Jul 17 2026

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

0400 PM     Flash Flood      11 W Huachuca City      31.66N 110.53W
07/16/2026                   Santa Cruz         AZ   Trained Spotter

            [Delayed report] 4 to 6 inches of water
            flowing across roadway near Rochelle and
            Lower Elgin Rd.

&&

KLM

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 16, 5:01 PM MSTFlash Flood WarningTWCCochise3 hr
Jul 16, 5:12 PM MSTFlash Flood WarningTWCSanta Cruz3 hr
Jul 16, 5:23 PM MSTFlash Flood WarningTWCPima3 hr
Jul 16, 5:33 PM MSTFlash Flood WarningTWCGraham3 hr
Jul 16, 5:33 PM MSTFlash Flood WarningTWCPima3 hr
Jul 16, 6:26 PM MSTFlash Flood WarningTWCPima114 min
Jul 16, 6:31 PM MSTDust Storm AdvisoryTWCPinal74 min
Jul 16, 7:41 PM MSTFlash Flood WarningTWCPima3 hr
Jul 16, 8:16 PM MSTAreal Flood AdvisoryTWCPima4 hr
Jul 17, 8:53 AM MSTAreal Flood AdvisoryTWCPima112 min
Jul 17, 2:57 PM MSTFlash Flood WarningTWCCochise3 hr
Jul 17, 3:04 PM MSTFlash Flood WarningTWCPima3 hr
Jul 17, 3:05 PM MSTSevere Thunderstorm WarningTWCPima31 min
Jul 17, 4:54 PM MSTAreal Flood AdvisoryTWCPinal66 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.