651
FXUS65 KTWC 230746
AFDTWC

Area Forecast Discussion
National Weather Service Tucson AZ
1246 AM MST Fri Oct 23 2026

.SYNOPSIS...There will be a slight chance of showers and
thunderstorms along the New Mexico state line through Saturday. Dry
conditions are then expected areawide Sunday through Wednesday of
next week. High temperatures will be below normal into early next
week, warming to near normal during the middle of next week.

&&

.DISCUSSION...The upper low that brought severe weather to Arizona
the last two days has moved into the western Great Basin. Dewpoints
remain elevated across the eastern half of the forecast area in the
mid to upper 50s, with dewpoints in the mid to upper 40s across the
western half of the state. Cloud cover continues to hang in from
Tucson eastward with clear skies across the western half of the
state. KEMX radar shows a few light returns/showers over eastern
portions of the forecast area. Satellite layer blended PW values are
currently around one-half inch west of Tucson and between 0.75-1.00
inches to the east of the Tucson.

Through Saturday the main upper low will shift northeast into the
northern tier of states, while a secondary lobe of energy will drop
down the back side of the trough into the desert southwest. This
developing upper low will move into far southeast California tonight
and into western Arizona early Saturday. This system will then track
northeast across Arizona into southern Utah late Saturday night.
This system will not be like its predecessor, in that it will have
neither strong jet dynamic support or a subtropical moisture plume
to work with. However, there will still be enough moisture in place
to work with the trough/upper low to bring a slight chance of
showers and thunderstorms over far eastern portions of the forecast
area through Saturday.

Shortwave ridging and southwest flow aloft will then prevail Monday
through Wednesday of next week, as a series of upper lows move into
the Pacific Northwest. This will result in dry and warmer conditions
areawide across southeast Arizona.

During the latter half of next week the deterministic GFS/ECMWF
solutions diverge significantly. The Ensembles favor west coast
troughing, which is reflected in our grids/forecast, with high
temperatures lowering below normal and a slight chance of showers
and thunderstorms Thursday and a chance of showers/thunderstorms on
Friday.

Overall, high temperatures will be 1-5 degrees below normal through
Monday, near normal next Tuesday and Wednesday, lowering to 4-8
degrees below normal by the end of next week. Near freezing to sub-
freezing morning lows look likely in the White Mountains and
Hannagan Meadow Sunday morning through next Tuesday morning.

&&

.AVIATION...Valid through 24/12Z.
SCT-BKN clouds at 5k-9k ft AGL east of KAVQ to KOLS line, with clear
skies west of this line thru the forecast period. Slight chance of
-SHRA/-TSRA primarily east of a KDUG to KSAD line thru the forecast
cycle. SFC wind 12 kts or less, except in the vicinity of KALK and
KDUG between 23/18Z and 24/02Z when SFC wind will be 12-16 kts with
gusts to near 25 kts. SFC wind direction SWLY thru NWLY between
23/17Z and 24/03Z and variable in direction at other times. Aviation
discussion not updated for TAF amendments.

&&

.FIRE WEATHER...High temperatures will be below normal through
Monday, warming to near normal Tuesday and Wednesday of next week,
then lowering back below normal by the end of next week. There will
be a slight chance of showers and thunderstorms through Saturday
along the New Mexico state line and in the White Mountains. 20-foot
winds will generally be 15 mph of less through at least the middle
of next week. Minimum RH values will be in the 25-40 percent range
in the valleys through Sunday (higher in the mountains), lowering
into the 20-30 percent range next Monday through Wednesday.

&&

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

&&

$$

Zell

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

NWS Tucson (TWC) Office