001
FXUS65 KTWC 101515
AFDTWC

Area Forecast Discussion
National Weather Service Tucson AZ
815 AM MST Thu Jul 10 2025

.SYNOPSIS...

Temps remain in the triple digits across the lower desert today,
with isolated thunderstorm chances mainly confined to the
International Border this afternoon and evening.

&&

.UPDATE... Mostly clear skies this morning with some dissipating
clouds over southern Tohono O`odham Nation. Another hot day today
with high temperatures between 100 to 108 degrees with widespread
Moderate HeatRisk and localized Major HeatRisk in the Gila River
Valley. Moderate HeatRisk means that most individuals sensitive to
the heat will be will affected if they do not have effective
cooling or adequate hydration. Slight chance (15-30 percent) for
showers and thunderstorms this afternoon. The unfavorable
northwest flow aloft continues today and moisture recedes
southward into Mexico localizing the chance for thunderstorms to
far southeastern Cochise county along the International Border.
This morning, we lowered the chance for showers and storms from
the previous forecast to better portray the probabilities for
this afternoon. It will be breezy this early afternoon into the
early evening in the Gila River Valley with sustained northwest
winds of 20 25 MPH with gusts to 35 MPH. Otherwise, today looks
to be a fairly quiet weather day, mostly sunny skies and a hot
summer day.

&&

.PREV DISCUSSION... /issued 250 AM MST Thu Jul 10 2025/

.KEY MESSAGES...

- "Low-grade" monsoon pattern for the next several days. Storms
  and showers that develop will generally be east and south of
  Tucson.

- Decreasing temperature trend beginning today for the next 7 to
  10 days. Near normal temperatures by early next week. Minor to
  localized Moderate HeatRisk.

- Monsoon pattern ramps up again early next week.

&&

.DISCUSSION...

Desert SW remains under the influence of an upper level ridge of
high pressure, keeping temperatures slightly above normal for the
next few days. While the HeatRisk will be in the Minor to Moderate
Categories at most locales today, please continue to be cautious
and hydrate frequently if you are planning to be outdoors.

This will perpetuate our low grade monsoon pattern the next few
days and into the weekend, confining any isolated thunderstorm
activity to the International Border the next few afternoons and
evenings. With limited moisture available at the mid-levels and
the large scale wind pattern out of the N/NW, we likely won`t see
much in the way of widespread monsoonal activity for another
several days.

By Friday, the ridge will begin to retrograde westward over CA,
helping to moderate daytime high temperatures back toward normal,
before a more favorable monsoon pattern starts to take shape
early next week.

&&

.AVIATION...Valid through 11/12Z.

West/Northwesterly surface winds will dominate all terminals
through the forecast period, with an occasional gust at or around
15 mph due to daily diurnal trends. An isolated TS is possible
later this afternoon near KDUG, which may bring some gusty and
erratic winds. Skies should remain clear for the most of the
period with occasional FEW/BKN at or above 10k ft.

&&

.FIRE WEATHER...

Thunderstorm activity today will likely be confined to Southern
AZ along the International Border. Otherwise, isolated to low-
end scattered thunderstorm coverage is expected to the south and
east of Tucson into the weekend. The main threat for storms will
be the potential for strong gusty and erratic outflow winds 40-45
mph. Otherwise, an uptick in monsoon activity is possible later
this weekend and into next week as the upper high shifts to a more
favorable location aloft. Temperatures will remain above normal
this week, and back to near normal by early next week. Winds will
remain generally light and under 15 mph with the exception of
stronger winds in the Gila River Valley today and tomorrow with
northwest sustained winds around 15 to 20 MPH gusts to 30 MPH.

&&

&&

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

$$

Malarkey/ Singer

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