287
FXUS65 KTWC 232043
AFDTWC

Area Forecast Discussion
National Weather Service Tucson AZ
143 PM MST Sun Aug 23 2026

.SYNOPSIS...
Isolated to scattered afternoon and early evening thunderstorms
through Monday, then reduced storm chances through much of the
remainder of the work week. Strong, gusty winds and locally
heavy rainfall will be possible with any thunderstorm. High
temperatures will remain well above normal through the week
with an Extreme Heat Warning in effect for much of southeast
Arizona.

&&

.DISCUSSION...
The Gulf Surge continues this hour with breezy S/SW winds across
the lower deserts west of Tucson. TDs have eclipse 70 degrees in
far western Pima County with with low to mid 60s for portions of
Pima County (west of Tucson) and Santa Cruz. Across the metro,
TDs are in the 50s to lower 60s. This will set the stage for a
rather robust T`storm day. The question will be where and the
intensity. Looking over the most current MesoA and CAMs, point
to areas across western and central Pima and Santa Cruz Cos. One
or more clusters, potentially forming into a N/NW moving MCS is
possible. Main threats will be strong gusty winds to 60 mph,
especially across central Pima Co where the HREF has a 10% prob
of gusts in excess of 58 mph. Secondary threat will be a
localized flash flood threat where heavier rainfall rates are
realized and any backbuilding/cell mergers in the deeper
moisture from the gulf surge.

For the Tucson Metro, coverage will be more isolated in nature.
Any convection will evolve off the higher terrain and/or OFB
interaction likely from storms south and/or southwest of the
City. Coverage is even less further east where drier air
resides.

The Monsoon still looks to a downturn with much of the region
dry through most of the work week. Best opportunity (10-30%)
daily will be along the International Border and the White Mtns.
By Friday, there could be an expansion in coverage for most of
SEAZ to see at least isolated activity.

Heat remains front and center through the week, with widespread
Major Heatrisk with areas of Extreme. The Extreme Heat Warning
remains in effect through Saturday evening, with most of Santa
Cruz and Cochise Cos starting Tuesday.

&&

.AVIATION /20Z SUNDAY THROUGH 18Z MONDAY/...
Generally FEW-SCT clouds 9-13k ft AGL through the forecast period
with locally BKN clouds between 23/21Z and 24/09Z. Expect isolated
to scattered SHRA/TSRA this afternoon into evening, mainly west of a
KFHU-KSAD line, diminishing by 24/06Z. Currently VCTS for
KTUS/KOLS in the TAFs at this time. Gusts in excess of 40 kts
are expected with the stronger storms. Otherwise surface winds
light and terrain driven. Aviation discussion not updated for
TAF amendments.

&&

.FIRE WEATHER...
Isolated to scattered thunderstorms expected through Monday,
with the exception of along the NM border where mainly dry
conditions are expected. Thereafter, reduced chances for
thunderstorm activity for most of southeast Arizona for the rest
of the work week, though some isolated storms will continue
along the immediate Int`l border and White Mountain region.
Temperatures will remain well above normal through most of the
week with Monday being the coolest day of the period. Drier
conditions will return in the middle of the week with minimum
relative humidity values mainly 10-18 percent in the valleys
and 20-30 percent in the mountains. Winds will generally remain
less than 15 mph and terrain driven through the week.

&&

.TWC WATCHES/WARNINGS/ADVISORIES...
Extreme Heat Warning until 8 PM MST Saturday for AZZ501-502-
504>506-509.
Extreme Heat Warning from 10 AM Tuesday to 8 PM MST Saturday
for AZZ503-507-508.

&&

$$

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