892
FXUS65 KTWC 152016
AFDTWC

Area Forecast Discussion
National Weather Service Tucson AZ
116 PM MST Sat Nov 15 2025

.SYNOPSIS...A series of low pressure systems will move across
the region over the next week. This will result in cooler
temperatures, a chance of showers and breezy conditions at times.
High temperatures of 5 to 8 degrees above normal today, will lower
to 2 to 4 degrees below normal on Sunday and then 10 to 13 degrees
below normal by the middle of next week.

&&

.DISCUSSION...An active weather pattern is in store for southeast
Arizona over the next week, as a series of low pressure systems move
across the region. These systems will bring cooler temperatures, a
chance of precipitation and breezy winds at times.

The first system is a cut off low currently centered off of the
southern California coast. This system will begin to lift northeast
tonight and move into the Great Basin Sunday and east into the
central plains on Monday. As this system moves northeast, it will
drag a frontal boundary from west to east across Arizona resulting
in a chance of showers/slight chance of thunderstorms and cooler
temperatures. Precipitation totals will be light; trace amounts to a
couple of hundredths from Tucson southward, up to one-tenth of an
inch north of Tucson and 0.15-0.40 inches in the mountains. Isolated
heavier amounts may be possible if thunderstorms do develop. Little
if any snowfall is expected with this system, as snow levels will be
at mountaintop levels around 10k ft. Breezy southwest winds will
occur on Sunday, with winds speeds of 15-25 mph and gusts to 30-35
mph. High temperatures will lower to 2-5 degrees below normal on
Sunday and Monday, or lower 70s from Tucson westward and in the mid
60s to around 70 degrees in the lower elevations of Santa Cruz,
Cochise, Graham and Greenlee counties. Overall, only very
minor/nuisance impacts are expected with this system.

Another low pressure system will then quickly drop southward through
the west coast trough on Monday into north central California. This
system will then move into southeastern California early Tuesday,
into western Arizona Tuesday night/early Wednesday and then lift
northeast into the Four Corners by Thursday. Precipitation chances
spread from west to east across southeast Arizona starting Monday
evening into Tuesday, with precipitation chances across all of
southeast Arizona Tuesday evening through Wednesday, before winding
down from west to east Wednesday night into early Thursday. Storm
total precipitation amounts will be higher with this second system,
with valley totals generally in the 0.20-0.40 inch range and 0.50-
0.75 inches in the mountains. This system will also be colder than
the first one, with snow levels lowering down to the 7.0k-7.5k ft
level during the day Wednesday. Snowfall totals are currently in the
2-4 inch range in the Sky Island Mountains south of Tucson and in
the 4-7 inch range for Mount Lemmon, Mt Graham and across northern
Greenlee County. High temperatures will lower to 10-13 degrees below
normal on Wednesday, with highs in the lower to mid 60s from Tucson
westward and in the mid 50s to around 60 degrees in the lower
elevations of Santa Cruz, Cochise, Graham and Greenlee counties.
Breezy winds are also expected Tuesday and Wednesday, especially to
the east/southeast of Tucson, with south-southwest winds of 15-20
mph and gusts to around 30 mph. Colder morning low temperatures are
forecasted behind the system Thursday and Friday mornings and more
widespread freezing low temperatures are likely over portions of
eastern Santa Cruz, southwest Graham and portions of Cochise
counties. Overall, minor to moderate impacts are expected with this
system.

The models point to yet another system late next week into next
weekend moving into the region. The models differ on the timing of
this system, with the GFS cutting the low off along the southern
California coast Friday/Saturday while the ECMWF is more progressive
moving the system across Arizona in the Friday/Saturday time frame.
Ensembles models tend to favor the more progressive solution. How it
plays out will determine the timing for precipitation chances, but
all of these model solutions keep below normal high temperatures
through at next weekend. Stay tuned.

&&

.AVIATION...Valid through 17/00Z.
SCT-BKN clouds at 8k-11k ft AGL spreading from west to east across
southeast Arizona thru 16/03Z. Aft 16/03Z, SCT-BKN clouds at 7k-10k
ft AGL areawide, along with ISOLD-SCT -SHRA and a slight chance of
-TSRA thru the remainder of the forecast period. SLY/SWLY SFC wind
at 8-13 kts thru 16/02Z. Between 16/02Z and 16/16Z SFC wind less
than 10 kts and variable in direction. Aft 16/16Z, increasing
SLY/SWLY SFC wind with speeds of 15-20 kts and gusts to 25-30 kts by
16/19Z thru the remainder of the forecast cycle. Aviation discussion
not updated for TAF amendments.

&&

.FIRE WEATHER...Dry conditions with high temperatures 5-8 degrees
above normal will continue today. A storm system will move across
the area from the west this evening, with showers spreading from
west to east across southeast Arizona late tonight and Sunday. This
system will also bring a slight chance of thunderstorms and cooler
temperatures. Breezy southwest winds of 15-25 mph with gusts to 30-
35 mph are expected on Sunday. Another system is then expected to
move into the area late Monday through Wednesday of next week. This
system will bring another round of precipitation across southeast
Arizona, well below normal temperatures, along with breezy south to
southwest winds Tuesday. RH values will be on the increase, with Min
RH values well above critical levels Sunday through all of next week
(30-40 percent in the valleys and 50-60+ percent in the mountains).

&&

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

&&

$$

Zell

Visit us on Facebook...Twitter...YouTube...and at weather.gov/Tucson