316
FXUS65 KTWC 232109
AFDTWC

Area Forecast Discussion
National Weather Service Tucson AZ
209 PM MST Mon Dec 23 2024

.SYNOPSIS...
Dry weather this week. Near record temperatures possible through
Tuesday, then closer to normal temperatures from Christmas through
the end of the work week then warming back up again.

&&

.DISCUSSION...
Southeast Arizona is under mostly clear skies with the presence of
strong high pressure over the region. This is a `dirty` ridge in
the sense that high clouds are spilling through...including the
ones that came through last night, and additional high clouds
upstream. With the ridge axis orientation having shifted a bit
west of its location the last few days, heights and thicknesses
are lower and the airmass is therefore slightly cooler than the
last few days. Temperatures are on track to reach the 70s for
afternoon highs today, which is on the order of 10 to 15 degrees
warmer than normal for this time of year. One more day of near-
record temperatures in this stretch is on tap for Tuesday, as the
upper ridge axis oscillates back over us. This should nudge a few
lower elevation locations (including KTUS) back closer to 80
degrees.

Cooler weather is on its way for Christmas Day as an eastern
Pacific storm system moves inland, and tracks eastward along the
UT/AZ state line. This system has a 40-50% chance to bring some
light snow showers to the White Mountains, but most of the
forecast area should remain dry. A secondary trough comes through
later Thursday and brings a continued chance for light showers
over the Whites. The most noticeable weather change is the
cooldown these weather systems will bring. Our high temperatures
will be within a few degrees of normal Wednesday through Friday.
For reference, KTUS hasn`t seen a below normal high temperature
since December 10.

We warm right back up this weekend into early next week. Medium
range guidance and CPC outlooks show little to no chances for
precipitation through the end of the calendar year.

&&

.AVIATION...Valid through 25/00Z.
FEW-SCT clouds at or above 20kt ft area wide the next 24 hours.
SFC winds terrain driven less than 10 kts. Aviation discussion not
updated for TAF amendments.

&&

.FIRE WEATHER...
Dry conditions with above normal temperatures through the first
half of this week. A passing disturbance later in the week will
bring cooler temperatures and a chance of showers to the White
Mountains Christmas Day and Friday. Minimum relative humidity
values 10 to 15 percent in the valleys into the middle of this
week, with 15 to 25 percent expected in the higher terrain.
20-foot winds will mainly be less than 15 mph through this week.

&&

.CLIMATE...

RECORD OR NEAR RECORD HIGH TEMPERATURES NEXT 3 DAYS

DATE                         Dec 23           Dec 24
                          FCST RCD/YR      FCST RCD/YR
TUCSON INTL AIRPORT        77  80/2021      80  79/1936
AJO                        78  81/2005      80  82/1955
KITT PEAK                  61  65/2005      62  64/2005
ORGAN PIPE CACTUS          79  82/1950      79  82/1989
PICACHO PEAK               73  78/2021      75  76/2005
SAFFORD AG STATION         73  72/2005      72  73/1955
SIERRA VISTA FD            73  76/2024      74  74/1971
TOMBSTONE                  73  77/1955      73  76/2021
WILLCOX                    72  76/2024      72  73/2021

&&

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

$$

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