399
FXUS65 KTWC 221013
AFDTWC

Area Forecast Discussion
National Weather Service Tucson AZ
313 AM MST Fri Aug 22 2025

.SYNOPSIS...Daily chances for showers and thunderstorms with day
to day variability on coverage and intensity. Above normal
temperatures through the weekend and then trending down to near
normal by the start of next week. An Extreme Heat Warning in
effect until this evening.

&&

.DISCUSSION...Satellite imagery this morning showed considerable
debris cloud cover across Pinal, Graham and Greenlee counties
while it was clear to partly cloudy across Pima, Santa Cruz and
Cochise counties. Easterly flow aloft over the area with upper
high near the 4 corners. The area is split with PWATs less than 1"
E-SE of Tucson while values were up to 1.30" west of Tucson. Storm
activity later today will mostly be W-SW of Tucson where locally
heavy rain and gusty winds the main threat. Otherwise another hot
August day with Extreme Heat Warning in effect into this evening.

E-SE flow aloft continues across the area this weekend with drier
air east of Tucson and wetter air west of Tucson. Thus the main
focus for afternoon/evening storms this weekend will mainly be
W-SW of Tucson. There will be localized areas of Major HeatRisk
but not large enough area at this time to warrant a Warning to be
hoisted.

Next week starts off similar to this weekend before the upper
high moves east into Texas bringing a deeper and moister S-SE flow
aloft over the area resulting in an uptick in coverage of
afternoon and evening showers and thunderstorms Tuesday into
Thursday. With the added moisture and lower thickness values, high
temperatures will be cooling off to, dare I say it, below normal
levels.

&&

.AVIATION...Valid through 23/12Z.
FEW-SCT clouds lcly BKN 10k-13k ft AGL diminishing thru 22/18z.
Aft 22/18z, FEW-SCT 9k-12k ft AGL with ISOLD -SHRA/-TSRA. SFC
winds will generally be E-SE less than 12 kts through the forecast
period. Expect gusty and erratic winds with any -TSRA. Aviation
discussion not updated for TAF amendments.

&&

.FIRE WEATHER...Expect daily chances for rain showers and
thunderstorms into next week with day to day variability of
intensity and coverage of storms. Temperatures will be running
above normal through the weekend with an Extreme Heat Warning in
effect today for the lower elevations. Winds will generally remain
less than 15 mph with the afternoon gustiness into next week. Min
RHs will be 15-20 percent in the low elevations and 20-30 percent
in the mountains through the weekend. Deep monsoon moisture will
return early next week to provide higher wetting rain chances and
coverage as well as better min RHs and below normal temperatures.

&&

.TWC WATCHES/WARNINGS/ADVISORIES...
 Extreme Heat Warning until 8 PM MST this evening for AZZ501>507-509.

&&

$$

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