Wildfire in Arizona, May 21 to 31, 2025

Area Forecast Discussion
National Weather Service Tucson AZ
315 PM MST Wed May 21 2025

.SYNOPSIS...A building ridge of high pressure across the region will
result in a slight warming trend the next few days across Southeast
Arizona. High temperatures will top out Thursday at 7 to 10 degrees
above climatological normal. Light winds with occasional afternoon
gustiness due to strong heating can be expected today and Thursday,
with breezy afternoon winds returning Friday.

&&

.DISCUSSION...Sunny warm day across southeast Arizona with high
temperatures this afternoon running 4 to 8 degrees warmer than
yesterday. Warmer tomorrow, up to 3 degrees, as height/thickness
values peak across the area. Widespread triple-digit highs across
the lower deserts of Pima/Pinal counties.

Friday: Slightly cooler highs as upper level heights start to
lower in advance of approaching upper level trof. See fire weather
section below for fire details.

This weekend: Near normal highs and afternoon breezes as above
mentioned trof moves across the state.

Next week: Another upper level trof moves into the west coast with
an upper level low developing off southern CA/northern Baja. To
our east there will be a gradual westward push of mainly mid-level
moisture across New Mexico. May see some build-ups over the far
eastern mountains with a very low end chance (<10%) for dry
lightning for the White mountains Tue/Wed. Something to keep an
eye on.

&&

.AVIATION...Valid through 23/00Z.
SKC thru much of valid pd. A few cirrus clouds AOA 20k ft AGL
moving in from the W aft22/19z. SFC winds terrain driven less than
12 kts thru much of valid pd. Aviation discussion not updated
for TAF amendments.

&&

.FIRE WEATHER...A building ridge of high pressure across the
region will result in a slight warming trend the next few days
across Southeast Arizona. High temperatures will top out Thursday,
with afternoon readings 100-104 from Tucson westward (and upper
Gila River Valley) and in the 90s across the eastern valleys.
Although occasionally gusty winds will be observed due to the
significant surface heating the next several days, the strongest
winds will occur Friday as a dry disturbance tracks across the
area. At this time, wind speeds should stay below critical fire
weather thresholds (Southwest 15-20 mph with gusts to 30-35 mph)
Single digit min RH values at all elevations over the next week
with poor overnight recoveries.

There is the potential for some mid-level moisture to move into
far eastern areas by the middle of next week. This may lead to
some afternoon buildups and/or isolated dry lightning strikes
Tuesday and Wednesday of next week. At this time, confidence in
this scenario remains low.

&&

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

&&

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