Mammoth, Arizona Weather Forecast Discussion

251
FXUS65 KTWC 271008
AFDTWC
Area Forecast Discussion
National Weather Service Tucson AZ
308 AM MST Sat Sep 27 2025
.SYNOPSIS...Drier air has moved in across the area which will
limit the chance of showers and thunderstorms this weekend. High
will be below normal this weekend then warm next week under dry
conditions.
&&
.DISCUSSION...Mostly clear conditions early this morning. Water
vapor imagery showed quasi-stationary upper low over SE CA. This
system advected much drier air across southeast Arizona over the
past 24 hours with PWAT values down below an inch across much of
the area this morning. With drier atmosphere in place today, only
a few storms are expected this afternoon with PoPs mostly less
than 30%. The Flash Flood Watch that was in effect until this
evening was cancelled late last night. The upper low opens up
Sunday as it moves across northern Arizona. Slight chance of
afternoon showers/storms mainly northeast of Tucson. High
temperatures this weekend will run 2 to 5 degrees below normal.
Dry and warmer next week as we close out September and the 2025
Monsoon and welcome in October.
&&
.AVIATION...Valid through 28/12Z.
SKC to SCT 10k ft AGL. ISOLD -SHRA/TS. SFC winds SELY less than 10
kts thru 27/17z, then SLY to SWLY at 10-15 kts with gusts up to
25 kts thru 28/03z, then SELY less than 10 kts thru end of valid
period. Aviation discussion not updated for TAF amendments.
&&
.FIRE WEATHER...Isolated showers and thunderstorms this weekend.
General winds will be south to southwest through next week with
speeds up to 15 mph and gusts up to 20 mph. The above normal
moisture will keep min RHs above 25 percent through most of the
weekend. Temperatures will be around normal through the weekend.
Next week, temperatures will be slightly above normal with winds
less than 15 mph and min RHs 18-22 percent in the valleys and
25-30 percent in the mountains.
&&
.TWC WATCHES/WARNINGS/ADVISORIES...None.
&&
$$
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NWS TWC Office Area Forecast Discussion