Alert archive / Arizona / Severe Thunderstorm Warnings in 2026

Severe Thunderstorm Warning 261, NWS Tucson, AZ

September 11, 2026Pima County, Santa Cruz County, Arizona

NWS Tucson, AZ issued this severe thunderstorm warning at Sep 11, 2026, 3:39 PM MST for Pima County, Santa Cruz County, Arizona. It was in force for 51 min. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued
Sep 11, 2026, 3:39 PM MST (22:39 UTC)
Expired
Sep 11, 2026, 4:30 PM MST
In force
51 min
Issued by
NWS Tucson, AZ
Area
Storm-based polygon
Hail
0.0 in
Wind
60.0 mph

Counties Pima County, AZ, Santa Cruz County, AZ

The radar

The Tucson radar (KEMX), 48 km from the middle of the area, began a volume at 22:39 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 severe thunderstorm 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 202 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 2026-09-11Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 843 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 2026-09-11The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 72 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
843 J/kg
Mixed-layer CIN
-151 J/kg
Mixed-layer LCL
1773 m above ground
0-6 km bulk shear
12 kt
0-1 km storm-relative helicity
72 m²/s²
0-3 km storm-relative helicity
54 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

278 
WUUS55 KTWC 112239
SVRTWC
AZC019-023-112330-
/O.NEW.KTWC.SV.W.0261.260911T2239Z-260911T2330Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Tucson AZ
339 PM MST Fri Sep 11 2026

The National Weather Service in Tucson has issued a

* Severe Thunderstorm Warning for...
  East Central Pima County in southeastern Arizona...
  North Central Santa Cruz County in southeastern Arizona...

* Until 430 PM MST.

* At 339 PM MST, a severe thunderstorm was located 8 miles south of
  Green Valley, moving northwest at 10 mph.

  HAZARD...60 mph wind gusts.

  SOURCE...Radar indicated.

  IMPACT...Expect damage to roofs, siding, and trees.

* Locations impacted include...
  Sahuarita, Green Valley, Amado and Arivaca Junction.

This includes Interstate 19 between mile markers 25 and 42.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Seek shelter inside a well-built structure and stay away from
windows. This storm is capable of producing damaging winds.

&&

LAT...LON 3170 11116 3183 11132 3190 11121 3190 11096
      3166 11088 3165 11111
TIME...MOT...LOC 2238Z 142DEG 9KT 3174 11105

HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...0.00 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH

$$

EDWARDS/PATEL
2 follow-up statements
251 
WWUS55 KTWC 112254
SVSTWC

Severe Weather Statement
National Weather Service Tucson AZ
354 PM MST Fri Sep 11 2026

AZC019-023-112330-
/O.CON.KTWC.SV.W.0261.000000T0000Z-260911T2330Z/
Pima AZ-Santa Cruz AZ-
354 PM MST Fri Sep 11 2026

...SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 430 PM MST FOR
EAST CENTRAL PIMA AND NORTH CENTRAL SANTA CRUZ COUNTIES...

At 354 PM MST, a severe thunderstorm was located over Arivaca
Junction or 7 miles southwest of Green Valley, moving northwest at 5
mph.

HAZARD...60 mph wind gusts and quarter size hail.

SOURCE...Radar indicated.

IMPACT...Hail damage to vehicles is expected. Expect wind damage to
         roofs, siding, and trees.

Locations impacted include...
  Sahuarita, Green Valley, Amado and Arivaca Junction.

This includes Interstate 19 between mile markers 27 and 42.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Seek shelter inside a well-built structure and stay away from
windows. This storm is capable of producing damaging winds and large
hail.

&&

LAT...LON 3170 11116 3183 11132 3190 11121 3190 11096
      3168 11089 3167 11113
TIME...MOT...LOC 2239Z 146DEG 2KT 3174 11107

HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...1.00 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH

$$

EDWARDS/PATEL
697 
WWUS55 KTWC 112327
SVSTWC

Severe Weather Statement
National Weather Service Tucson AZ
427 PM MST Fri Sep 11 2026

AZC019-023-112337-
/O.EXP.KTWC.SV.W.0261.000000T0000Z-260911T2330Z/
Pima AZ-Santa Cruz AZ-
427 PM MST Fri Sep 11 2026

...SEVERE THUNDERSTORM WARNING WILL EXPIRE AT 430 PM MST FOR EAST
CENTRAL PIMA AND NORTH CENTRAL SANTA CRUZ COUNTIES...

The storm which prompted the warning has weakened below severe
limits, and no longer poses an immediate threat to life or property.
Therefore, the warning will be allowed to expire. However, small hail
and heavy rain are still possible with this thunderstorm.

&&

LAT...LON 3170 11116 3183 11132 3190 11121 3190 11096
      3168 11089 3167 11113
TIME...MOT...LOC 2254Z 146DEG 2KT 3175 11107

$$

EDWARDS

What forecasters said that day

The local office's own words before this severe thunderstorm 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 severe thunderstorm warning went out at Sep 11, 1:23 PM MST, 2 hours 16 minutes earlier. Its key messages:

  • -Isolated to scattered showers and thunderstorms this afternoon mainly south and east of Tucson capable of producing potentially heavy rainfall. -Slight Risk (Level 2 of 4) today for excessive rainfall that may lead to localized instances of flash flooding in flood prone areas. Sensitive low water crossings may become impassible. -Above normal moisture for mid September continues over the weekend into early next week resulting in continued chances for showers and storms and a Marginal Risk (Level 1 of 4) for excessive rainfall.
Area forecast discussion, Sep 11, 1:23 PM MST, 2 hours 16 minutes before
Area Forecast Discussion
National Weather Service Tucson AZ
123 PM MST Fri Sep 11 2026

.SYNOPSIS...A more active day is forecast across southeast Arizona
today with isolated to scattered showers and thunderstorms. Main
threat from storms today will be heavy rain and localized flash
flooding, especially across Santa Cruz county and southwest Cochise
county. A more typical isolated to scattered coverage of storms is
forecast this weekend into next week. Daily high temperatures will
fluctuate between near normal and a few degrees below normal.

&&

.KEY MESSAGES...

-Isolated to scattered showers and thunderstorms this afternoon
mainly south and east of Tucson capable of producing potentially
heavy rainfall.

-Slight Risk (Level 2 of 4) today for excessive rainfall that may
lead to localized instances of flash flooding in flood prone areas.
Sensitive low water crossings may become impassible.

-Above normal moisture for mid September continues over the weekend
into early next week resulting in continued chances for showers and
storms and a Marginal Risk (Level 1 of 4) for excessive rainfall.

&&

.DISCUSSION...Storms started forming early over high terrain areas
including the Huachuca and White Mountains around 11 am MST which
was a bit sooner than convective allowing models suggested.
Additional storm activity is anticipated to continue this afternoon
and evening with the strongest activity mainly focused south and
east of Tucson. The primary concerns with storms this afternoon
continues to be heavy rainfall (rates 1.0 to 2.5 inches per hour)
and frequent lightning. However, gusty and erratic outflow winds to
around 45 mph cannot be ruled out with the strongest storms as well.
Heavy rainfall may result in isolated instances of flash flooding,
especially across Santa Cruz County, southwest Cochise County, and
far southeast Pima County. Portions of eastern Santa Cruz county and
SW Cochise county has seen heavy rain over the past 72 hours, so the
soils are wet, and the San Pedro has had some increased flow several
days ago making them more susceptible to saturation this afternoon.
Flowing water can be expected in normally dry washes. Sensitive low
water crossings may become impassible with swift moving water.
Remember to remain alert, avoid driving through flooded roads, and
obey road closures.

The extent of showers and storms tomorrow will largely depend on
how the evolution of storm activity this afternoon and evening.
But even if we see less coverage of storms tomorrow, sufficient
moisture in place could again be supportive of heavy rainfall.
The 11/12Z HREF depicts a slight chance (10-30%) for heavy rain
exceeding 2 inches in a 3 hour period across Santa Cruz County
and southeast portions of Pima County.

Sunday through Thursday monsoonal moisture continues to remain in
place daily chances (20-50%) for showers and storms. Otherwise, high
temperatures will remain near normal through Monday afternoon before
we cool off and highs sag slightly below normal.

&&

.AVIATION...Valid thru 13/00Z.
SCT-BKN 6k-9k ft AGL. ISOLD to SCT SHRA/TSRA mainly S and E of KTUS
thru 12/02Z and again aft 12/21Z. Isold VSBY 1-3 miles nr TS. Lclzd
TS outflow winds of 30-40 kts. Otrw, SFC winds WLY/NWLY at 6-10 kts
thru 12/04Z and again aft 12/17Z. At other times, SFC winds will
be terrain driven and less than 10 kts. Aviation discussion not
updated for TAF amendments.

&&

.FIRE WEATHER...Scattered showers and thunderstorms today. A
more typical isolated to scattered coverage of storms is forecast
this weekend into next week. High temperatures will will fluctuate
between near normal and a few degrees below normal. Min RH values
mainly 20 to 45 percent in the valleys and 35 to 65 percent in the
mountains over the next week. RH recoveries will continue to be
excellent overnight. Winds will generally remain less than 15 mph
and terrain driven. Gusty and erratic winds will accompany
thunderstorms.

&&

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

&&

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The office that day

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

IssuedProductOfficeCountiesLasted
Sep 11, 12:20 PM MSTAreal Flood AdvisoryTWCCochise, Santa Cruz3 hr
Sep 11, 3:05 PM MSTSevere Thunderstorm WarningTWCSanta Cruz40 min
Sep 11, 4:08 PM MSTAreal Flood AdvisoryTWCPima, Santa Cruz3 hr
Sep 11, 4:36 PM MSTAreal Flood AdvisoryTWCCochise3 hr

Nearby

Severe Thunderstorm Warnings in Arizona, 2026Every severe thunderstorm 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.