Cold in Arizona, December 28, 2025

Area Forecast Discussion
National Weather Service Tucson AZ
250 PM MST Sat Dec 27 2025

.SYNOPSIS...Mainly dry tonight into Sunday with some patchy fog
developing mainly east and south of Tucson. A back door cold front
will bring gusty east winds to the area late Sunday night into
Tuesday along with a slight chance of precipitation to areas east
of Tucson. Another system will bring a good chance of
precipitation next Wednesday and Thursday as we turn the calendar
from 2025 to 2026. Temperatures will remain near normal levels
into next week.

&&

.DISCUSSION...The bulk of the precipitation has ended across SE AZ
although can't rule out a brief sprinkle across the eastern zones
into early this evening. Otherwise drier air pushing in and with
moist near surface conditions overnight, patchy fog is possible
especially south and east of Tucson. Temperature for the next 7
days will be right around normal.

Sunday will be dry with weak upper level trofiness to our west.

Sunday night into Monday night: Gusty easterly winds develop as a
back-door cold front pushes in from the east. This front will
advect some low-level moisture into the eastern zone for a slight
chance of valley showers/mountain snow showers. There is a low end
chance for a few valley locations Monday night briefly seeing
mixed rain/snow.

Tuesday: Slight chance (10%-20%) for a few rain/snow showers far
eastern areas otherwise dry area wide.

Additionally on Monday and Tuesday, we will be watching a large
upper low west of Baja CA and how much tropical moisture is
wrapped into this feature.

As we close out 2025 (Wed) and ring in 2026 (Thu), our area will
see the influences of the above mentioned low as it spreads
tropical moisture into the area and bringing a good chance of a
wet start to 2026. Still uncertainty on the timing and how much
QPF will be associated with this feature. Due to the warm nature
of this system, any accumulating snow will be near the mountain
peaks. Stay tuned.

&&

.AVIATION...Valid through 29/00Z.
SCT-BKN 5k-8k ft AGL with SCT layers AOA 12k ft passing through.
Patchy FG dvlpg btwn 28/04z and 29/13z. Low confidence that any FG
will impact TAF sites so left out on the 28/18z issuance. SFC
winds SWLY/WLY 8-12 kts thru 28/02z then again after 28/19z. SFC
winds at other times less than 10 kts. Aviation discussion not
updated for TAF amendments.

&&

.FIRE WEATHER...A weather system will move east of the area
tonight with dry weather its wake for Sunday. A back-door cold
front will move into Greenlee, Graham and Cochise counties late
Sunday into Monday, bringing with it gusty easterly winds and a
slight chance of valley rain and mountain snow east of Tucson.
Can't rule out a brief period of mixed rain and snow for a few of
the valley locations in the above mentioned counties.

Temperatures will remain near normal levels this weekend into
next week. 20-foot winds will be 15 mph or less and terrain driven
this weekend. Min relative humidity values will be elevated today
ranging from 45-65 percent in the valleys and 60-80 percent in
the mountains. Drier air moving into the area will then lower Min
RHs to 25-35 percent valleys and 35-50 percent in the mountains
Sunday into early next week. Breezy to gusty southeast winds
return Monday morning especially for the Gila River Valley with a
greater than 50% chance for gusts in excess of 30 mph from Monday
afternoon to early Tuesday morning.

&&

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

&&

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