459
FXUS65 KTWC 262213
AFDTWC

Area Forecast Discussion
National Weather Service Tucson AZ
313 PM MST Thu Jun 26 2025

.SYNOPSIS...Afternoon and evening chances for showers and
thunderstorms are possible daily through Friday in eastern
locations, mainly closer to the New Mexico border. Temperatures
become hotter this weekend as conditions dry out. Moisture is
expected to increase next week and likely bring the start to the
monsoon season.

&&

.DISCUSSION...Doppler radar this afternoon showed isolated
showers/thunderstorms along/near the AZ/NM border. One slow moving
cell over the Chiricahua Mtns has produced almost 2" of rain per
MRMS as of this writing. This prompted a Flash flood warning to
be issue. This area in where nearly 1" of PW resides. There will
be a continued threat for isolated heavy rainers near AZ/NM border
into this evening.

Friday: Far eastern areas remain on the western edge of deeper
moisture that is over NM for a continued slight chance of
afternoon/evening storms. Elsewhere dry with highs a few degrees
above normal.

This weekend into Monday: Heating up as an upper level high
builds over the region bringing another round of near record
highs and Moderate to locally Major HeatRisk. Went ahead of
hoisted up Extreme Heat Watch for the lower deserts (Pima, SE
Pinal and Graham counties). Highs will be the hottest on Monday
ranging 108 to 113 degrees. Convection wise any storms that
develop this weekend will be near the International border of
Santa Cruz and Cochise counties. Monday will see a slight uptick
in thunderstorm chances east and south of Tucson.

Tuesday through Thursday: Moisture values increase each day as
MCS`s that develop south of the International border send outflow
boundaries north across the area. With the increase in moisture
there is the increased threat of isolated heavy rainers and flash
flooding. Can`t rule out the other thunderstorm impacts of strong
gusty winds and blowing dust. Game on next week for Monsoon `25.

&&

.AVIATION...Valid through 28/00Z.
W of KTUS...SKC. KTUS E...SCT clouds around 10k ft AGL with
isold -SHRA/TS near AZ/NM border, diminishing after 27/03z then
developing again after 27/19z. Isold gusts up to 40 kts nr -TSRA
otherwise winds light and under 12 kts with an ocnl aftn gust up
to 20 kts. Aviation discussion not updated for TAF amendments.

&&

.FIRE WEATHER...Chances for isolated showers and thunderstorms
through tomorrow east of Tucson. Minimum relative humidities from
10 to 20 percent today and tomorrow, with a drying and warming
trend this weekend. Winds generally light and under 15 mph with
isolated gusts up to 45 mph under any thunderstorm through Friday.
Moisture should begin to arrive next week and bring a start to
the monsoon season across southeastern Arizona.

&&

.TWC WATCHES/WARNINGS/ADVISORIES...
 Extreme Heat Watch from Monday morning through Monday evening
  for AZZ501-502-504>506-509.

&&

$$

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