121
FXUS65 KTWC 132104
AFDTWC

Area Forecast Discussion
National Weather Service Tucson AZ
204 PM MST Wed Aug 13 2025

.SYNOPSIS...Scattered thunderstorms across Southeast Arizona today will
be capable of strong thunderstorm outflow winds with the
potential for dense blowing dust. Better wetting rain chances will
increase tomorrow through Friday. Expect daily shower and
thunderstorm chances into next week with day to day variability in
chances. High temperatures will generally remain above normal
through Thursday, cooling Friday into this weekend.

&&

.DISCUSSION...Two thunderstorms have recently developed in the
last hour along the Chiricahua Mountains. They are nearly
stationary and will fizzle out due to the lack of steering flow
and not enough critical ingredients for thunderstorm
sustainability. Thunderstorm coverage will expand west across
Southeast Arizona with the furthest extent to near Why. These
areas are under decent moisture content of 1.3 inches, increasing
instability with decreasing CIN, and flow along the terrain to
help with the lift. We currently have a lot of CIN, around -100
J/kg based on the RAP analysis. The conditions will slowly improve.
We need more surface heating this afternoon to help erode the CIN
and bringing about better instability. Therefore, storm intensity
will pick up later this afternoon...around the evening
commute...and peaking in the evening. Storm chances will taper
down through the rest of the night.

The main threat for today will be the strong gusty outflows. 12Z
HREF has high probabilities for gusty winds above 30 kts and 10
percent chance for greater than 50 kts, mainly in eastern Pinal
County to Graham county border and south-central Pima county.
Outflows will help initiate other storms in central Pima county to
Tucson metro. With the dry soil moistures, blowing dust will be
an issue. Portions of the area will have potential for dense
blowing dust below 1 mile.

Tomorrow, our synoptic pattern will transition with the high
pressure center moving our east and a Pacific trough moving into
the region. The trough will bring southwesterly flow and the
influence to initiate thunderstorms and rain showers. The best
wetting rain chances will peak by Friday and tapering down through
the weekend. Increasing potential for overnight convection and
rain showers during this time period. Rainfall amounts will be
generally low with pockets of heavier amounts due to storms.


Beyond, temperatures will be near normal by the weekend with the
daily variability of thunderstorm intensity and coverage.
Moisture will be lower through the weekend. Next week,
temperatures will be running above normal with daily chances for
rain showers and thunderstorms. High Pressure is projected to be
near the Four Corners by the middle of next week. This will be in
a better position to bring deep monsoon moisture for better
chances for rain.

&&

.AVIATION...Valid through 15/00Z.
SCT-BKN 8-12k ft AGL with SCT -SHRA/-TSRA expanding in intensity
and coverage through 14/06Z. Lingering -SHRA will be possible in
the overnight hours through 14/10Z. SCT -SHRA/-TSRA chances return
after 14/18Z through the forecast period. Gusty and erratic winds
up to 45 kts near any TS this afternoon with localized VSBY below
1SM possible in BLDU. Otherwise, surface winds should remain
below 15 knots with the occasional afternoon gusts up to 20 kts.
Aviation discussion not updated for TAF amendments.


&&

.FIRE WEATHER...High temperatures will remain several degrees
above through tomorrow then near normal Friday into this weekend.
Today will be an active thunderstorm day across Southeast Arizona
as the storms will be capable of producing strong, gusty and
erratic outflows to 40-45 mph with areas of dense blowing dust
possible in the valleys. Although the highest chances and coverage
for wetting rain showers and thunderstorms will be today through
Friday. Daily chances for thunderstorms and wetting rains will
persist this weekend into next week with daily variability in
coverage and intensity. Min RHs will generally be around 15-25
percent in the lower elevations and 20-35+ percent in the
mountains through Thursday, increasing Friday and Saturday as
deeper moisture tracks across the area. Winds will generally be
less than 15 mph with typical afternoon gusts up to 20 mph into
next week.


&&

.TWC WATCHES/WARNINGS/ADVISORIES...
Blowing Dust Advisory until 11 PM MST this evening for
AZZ501>509.

&&

$$

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