Sasabe, Arizona Weather Forecast Discussion

321
FXUS65 KTWC 232123
AFDTWC
Area Forecast Discussion
National Weather Service Tucson AZ
223 PM MST Tue Sep 23 2025
.SYNOPSIS...Above normal moisture across the region will result
in isolated to scattered rain showers and thunderstorms today and
less so tomorrow. A weather system will bring stronger storms
starting Thursday with impacts gusty winds and risks for flash
flooding. A Flash Flood Watch is in effect from Thursday morning
for areas east of Tucson expanding to Tucson eastward Friday
morning lasting through Saturday evening
&&
.KEY MESSAGES...
Tomorrow: Isolated thunderstorms and rain showers for areas south
and southeast of Tucson. Temperatures will be running 3-6 degrees
above seasonal normal.
Thursday-Weekend: A weather system will bring stronger
thunderstorms and high chances for wetting rain showers.
- A Flash Flood Watch is in effect from Thursday morning for areas
  east of Tucson expanding to Tucson eastward Friday morning
  lasting through Saturday evening.
- Expect strong gusty and erratic winds from thunderstorms more so
  Tucson westward.
&&
.DISCUSSION...Clouds and small showers are starting to build up.
Today there is a slight chance (15-25%) for isolated thunderstorms
and showers for areas south and southeast of Tucson. While there
is suitable moisture, 1.46 inches of PWAT observed by the 18Z
sounding, we are lacking a lifting mechanism. The low pressure
system, affectionately named the San Diego Low as noted in the
previous discussion, that will lead to enhanced weather later
this week is currently off the coast of southern California.
Today, any storms and shower that develop today will be driven by
daytime heating. High temperatures will be a few degrees warmer
than yesterday with highs in the upper 90s in the lower elevations.
Tomorrow, the aforementioned low pressure system will remain off
the coast of southern California which will further limit the
potential for thunderstorms and showers to develop.
The San Diego Low will start to move into our region Thursday
which was begin the above normal surge of moisture from the Gulf
of California. This continues to suggest organized thunderstorms.
Starting on Thursday, diffluence aloft will bring two main
impacts for the region. There is a likely hood for strong to
severe thunderstorms with the possibility for gusty erratic winds
and hail. EFI shows 89% confidence for CAPE and shear values above
climate norms. CAPE values will generally be 1,000-1,600 J/kg
with shear at least 15 kts and possibly up to 25 kts on Thursday
and Friday. We will also be sitting at 120-150% above normal
precipitable water by the end of the week. Ensemble cluster
analysis continues to highlight Friday as one of the wettest days
of the week with rainfall amounts at least 0.25" for widespread to
areas getting up to an inch for a single day. The south-southwest
flow will enhance more rainfall amounts closer to an inch and
possibly greater on the mountains and windward facing sides.
Therefore, a Flash Flood Watch has been issued for Thursday
morning for areas east of Tucson expanding to Tucson eastward
Friday morning lasting through Saturday evening.
Starting Saturday evening into Sunday, long range models begin to
deviate in the movement of the low pressure system. Generally it
will continue to move eastward but the timing and intensity
varies. More to come as we get closer!
&&
.AVIATION...Valid through 25/00Z.
FEW to SCT clouds AOA 5 to 10 k ft AGL KAVQ southward. Isolated
TSRA/SHRA 24/02Z, mainly south and southeast of KTUS. Gusty and
erratic winds to around 35 kts will accompany thunderstorms.
Outside of thunderstorms, SFC winds will be generally less than 12
kts from the northwest in the afternoon becoming light and
variable overnight. Aviation discussion not updated for TAF
amendments.
&&
.FIRE WEATHER...Above normal monsoonal moisture will linger
through tomorrow, providing isolated thunderstorms and rain
showers south and east of Tucson. Min relative humidities will be
bottoming out at 20-30 percent today through Thursday. By
Thursday, a weather system will bring higher chances for wetting
rain showers and stronger thunderstorms through the start of the
weekend. Outside of thunderstorm winds, general winds will be less
than 15 mph with the occasional gust up to 20 mph today and
tomorrow. The Gila Valley will have southeasterly breezes in the
early Thursday morning. Expect southerly to southwesterly breezes
late Thursday through Friday due to the incoming weather system.
Daytime temperatures will be running 3-6 degrees above normal
through at least Thursday and dropping to near normal by the
weekend.
&&
&&
.TWC WATCHES/WARNINGS/ADVISORIES...
Flood Watch from Friday morning through Saturday evening for
AZZ503-504-506-514.
Flood Watch from Thursday morning through Saturday evening for
AZZ507>513.
&&
$$
Malarkey
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NWS TWC Office Area Forecast Discussion