Severe Thunderstorm Warning 99, NWS Tucson, AZ

264 
WWUS55 KTWC 040108
SVSTWC

Severe Weather Statement
National Weather Service Tucson AZ
608 PM MST Mon Aug 3 2026

AZC003-040118-
/O.EXP.KTWC.SV.W.0099.000000T0000Z-260804T0115Z/
Cochise AZ-
608 PM MST Mon Aug 3 2026

...SEVERE THUNDERSTORM WARNING WILL EXPIRE AT 615 PM MST FOR CENTRAL
COCHISE COUNTY...

The storm which prompted the warning has moved out of the area.
Therefore, the warning will be allowed to expire. However, gusty
winds and heavy rain are still possible with this thunderstorm.

To report severe weather, contact your nearest law enforcement
agency. They will send your report to the National Weather Service
office.

&&

LAT...LON 3221 10983 3226 10955 3202 10945 3172 10952
      3184 10994 3217 10995
TIME...MOT...LOC 0029Z 24DEG 11KT 3205 10967

$$

JRM

Area Forecast Discussion
National Weather Service Tucson AZ
117 PM MST Mon Aug 3 2026

.SYNOPSIS...

Chances for thunderstorms will develop each afternoon and
evening this week with day to day variability. Thunderstorms may
produce severe outflow winds with areas of blowing dust, as well
as locally heavy rainfall with a flash flooding risk. High
temperatures will remain a few degrees above normal through the
week.

&&

.DISCUSSION...

An upper level high currently centered over central Arizona will
gradually lift north into the Four Corners through the week.
The high's current position and orientation has allowed for
active easterly flow to set up over southeastern Arizona, while
surface dew points have increased to the upper 50s to lower 60s
across the area. Under modestly divergent flow aloft,
thunderstorms are expected to initiate over the Sky Islands and
White Mountains early to mid afternoon today, with the easterly
flow moving and expanding their coverage westward through the
evening. 1000-2000 J/kg of MLCAPE and 1.2-1.6 inches of
precipitable water will provide ample instability, combining
with 15-25 knots of effective shear for a severe, organized
thunderstorm threat. While most of southeastern Arizona has at
least a 30-50 percent chance of thunderstorms today, coverage
should be greatest through southern Cochise, Santa Cruz, and
into south central Pima counties. It's in this area, especially
Santa Cruz, where potential for multiple storm cells and
subsequent flash flooding is greater. A Flood Watch remains in
effect this afternoon and evening.

Elsewhere today a scattered severe wind threat remains,
especially where the 12Z HREF highlights the stronger potential
for organized severe outflows transitioning south off the White
Mountains this afternoon and this evening further west if
thunderstorm outflows organize west of Tucson. These winds will
likely produce a blowing dust threat, especially in dust prone
areas of I-10 east of Willcox and west of Tucson into Pinal and
through central to western Pima. A Blowing Dust Advisory remains
in place for this potential, with the possibility that warnings
will be needed where organized outflows kick up areas of very
dense blowing dust. Finally, an isolated severe hail threat
can't be ruled out with any sustained thunderstorm today.

On Tuesday the upper high nudges north slightly while keeping
easterly flow in place over the region. Again scattered
thunderstorms are likely, however location will depend on
today's action. 12Z guidance points to a later start with an
emphasis on eastern areas, mainly Graham, Greenlee, Cochise,
into Santa Cruz counties. Forecast soundings further west (such
as at Tucson) show a modest warming inversion which would line
up with the start in the east. A late evening push into
Pima/Pinal counties however can't be ruled out, depending on the
longevity and organization of outflows. The CAPE/shear
parameter space will remain impressive for severe winds and
blowing dust, along with an isolated flash flooding risk.
Additional blowing dust headlines for tomorrow in eastern
locations may be needed if this trend continues.

Favorable flow for monsoon activity continues through the week
with the upper high drifting north towards the Four Corners
with day to day variability. Forecast high temperatures will
fall to 2-4 degrees above normal, with some variability due to
thunderstorm activity and cloud cover.

&&

.AVIATION...Valid through 05/00Z.

Isolated to scattered thunderstorms expected to develop this
afternoon mainly between 03/21Z to 04/03Z with lingering
isolated activity through 04/06Z. Coverage around KTUS more
likely 03/23Z-04/03Z and KOLS 03/22Z-04/04Z. Gusty erratic winds
of 35-45 kts possible with any thunderstorm with potentially
blowing dust. Otherwise SFC winds WLY/NWLY at 8-12 kts with
occasional afternoon gusts to 20 kts. SFC winds light and
terrain driven after 03/04Z. Scattered thunderstorm chances
return Tuesday afternoon and evening. Aviation discussion not
updated for TAF amendments.

&&

.FIRE WEATHER...

An active monsoon period looks favorable this week with daily
chances for showers and thunderstorms each afternoon and
evening, with day to day variability. Minimum relative humidity
values will likely remain above 25-40 percent through the week
with temperatures 2-4 degrees above normal. Outside of
thunderstorms, winds terrain driven to around 10 mph with
occasional afternoon gusts to 25 mph.

&&

.TWC WATCHES/WARNINGS/ADVISORIES...
Extreme Heat Warning until 8 PM MST this evening for
AZZ501>509.
Flood Watch from 2 PM this afternoon to 10 PM MST this evening
for AZZ503-504-507-513-515.
Blowing Dust Advisory from 2 PM this afternoon to 8 PM MST
this evening for AZZ503-504-507>509.
Blowing Dust Advisory from 4 PM this afternoon to 10 PM MST
this evening for AZZ501-502-505-506.

&&

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

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Preliminary Local Storm Report
National Weather Service Tucson AZ
258 PM MST Mon Aug 3 2026

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

0245 PM     Tstm Wnd Gst     6 NE Nogales            31.42N 110.85W
08/03/2026  M66 MPH          Santa Cruz         AZ   ASOS

            ASOS station KOLS Nogales International
            Airport.

&&

Preliminary Local Storm Report
National Weather Service Tucson AZ
432 PM MST Mon Aug 3 2026

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

0425 PM     Dust Storm       San Simon               32.27N 109.23W
08/03/2026                   Cochise            AZ   Trained Spotter

            200 yard visibility in dense blowing dust.

0425 PM     Tstm Wnd Gst     San Simon               32.27N 109.23W
08/03/2026  M60 MPH          Cochise            AZ   Trained Spotter

&&

Preliminary Local Storm Report
National Weather Service Tucson AZ
448 PM MST Mon Aug 3 2026

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

0433 PM     Tstm Wnd Gst     San Simon               32.26N 109.23W
08/03/2026  M64 MPH          Cochise            AZ   Mesonet

            Mesonet station AZT16 San Simon.

&&