Severe Thunderstorm Warning 65, NWS Tucson, AZ

Area Forecast Discussion
National Weather Service Tucson AZ
248 PM MST Sat Sep 6 2025

.SYNOPSIS...Widely scattered showers and thunderstorms this
evening with the main threat from these storms being areas of
locally heavy rain producing isolated flash flooding. Below normal
temperatures this weekend. Drying trend commences Sunday with
only slight chances of precipitation, then dry early next week.
Some moisture mid to late week will result in slight chances for
showers and thunderstorms mid to late week. Most of the week will
have near normal temperatures.

&&

.DISCUSSION...Satellite imagery this afternoon showed extensive
cumulus field with isolated areas of TCU and CBs. Any showers or
thunderstorms that have developed so far this afternoon, as of
this writing, have mostly occurred across Santa Cruz county. No
change from the morning update with main focus area later this
afternoon into this evening for scattered showers and thunderstorms
that may produce localized heavy rain and increase flash flood
risk will be across Santa Cruz county and southern half of the
Tohono O'odham nation. The 06/12z HREF neighborhood probabilities
has this area with 50-70% chance for 1" rain and 10% chance of 3"
rain.

Sunday: Ridging aloft combined with drying trend will limited
mainly isolated thunderstorms across Cochise, Santa Cruz and
central/western Pima counties. Highs 3 to 5 degrees warmer than
today.

Monday/Tuesday: Increased southwest flow aloft out ahead of a
Pacific upper level trof will scour out deeper moisture and leave
most of the area high and dry with high temperatures at or a few
degrees above normal.

Wednesday thru Friday: As the above mentioned upper level trof
moves into the west coast, flow aloft turns southerly allowing
some deeper moisture advecting north, mainly across the eastern
half of the forecast area. Thus PoPs mainly in the 10% to 30%
range from Tucson east. Near normal high temperatures each day.

&&

.AVIATION...Valid through 08/00Z.
SCT-BKN 6k-10k ft AGL. ISOLD to SCT SHRA/TSRA thru 07/06Z. Expect
wind gusts up to 40 kts with the strongest storms. Surface winds
less than 10 kts and variable outside any thunderstorm activity.
Aviation discussion not updated for TAF amendments.

&&

.FIRE WEATHER...Minimum relative humidities 25 to 40 percent
through the weekend, lowering to 15 to 30 percent much of next
week. Widely scattered showers and thunderstorm chances this
evening, then drier air Sunday with just enough moisture for a
slight chance of showers and thunderstorms. Dry conditions prevail
Monday and Tuesday, with slight chances of showers and thunderstorms
mainly east of Tucson mid to late week as some moisture returns.
Surface winds mainly light through the forecast period, except
gusty and erratic in or near any thunderstorms. High temperatures
will be below normal this weekend then warming back to seasonable
levels for most of the week.

&&

.TWC WATCHES/WARNINGS/ADVISORIES...None.

&&

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