San Tan Valley, Arizona 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

901
FXUS65 KPSR 220501
AFDPSR

Area Forecast Discussion
National Weather Service Phoenix AZ
1000 PM MST Fri Feb 21 2025

.UPDATE...
Updated Aviation

&&

.SYNOPSIS...
Warm, dry, and tranquil weather will prevail this weekend with
temperatures continuing to range around 8 to 10 degrees above
normal. An anomalously strong ridge of high pressure is expected to
build over the Desert Southwest Sunday, reaching peak strength by
the middle of next week. This pattern will result in highs
approaching the lower 90s, or near record territory across the lower
desert communities Tuesday through Thursday.

&&

.DISCUSSION...
This weekend, deterministic models and ensemble members show a
steady warming trend as a pattern shift from NW flow aloft to upper
level ridging takes shape. On Saturday, another weak disturbance
will progress through the area but will result in little to no
change to our weather conditions as temperatures remain around 8 to
10 degrees above average. Ridging over the eastern Pacific will then
shift eastward, encompassing much of the Desert Southwest on Sunday.
This will result in highs mainly reaching into the lower 80s across
the lower deserts Sunday afternoon.

H5 heights will continue to rise above 580 dam late Sunday into
Monday which will promote a significant warm up across the entire
region early next week. NBM forecast temperatures are still showing
mid 80s Monday, and mostly the upper 80s starting Tuesday. A few
locations across the western deserts will likely see their first 90
degree reading of the year on Tuesday afternoon, which would be
around a month earlier than normal. The most likely timeframe for 90
degree highs in south-central AZ including the Phoenix Metro still
looks to be Wednesday-Thursday. During both of these days, highs
could reach record levels at Phoenix Sky Harbor (current chances of
reaching record highs at 40-60%).

&&

.PREVIOUS DISCUSSION...
Model guidance is still showing a potential shift in the weather
pattern late next week as a Pacific low is likely to develop and
approach the West Coast at some point between next Thursday and
Saturday. Timing and track differences among the ensembles make it
too difficult to know what is exactly in store for our region, but
guidance overall favors the low tracking through our region at some
point next weekend. For now, moisture availability with the system
looks to be fairly low, so any prospects for rain is also low. We
should however at least see a cooling trend by next weekend, but so
far NBM guidance indicates temperatures will remain above normal.

&&

.AVIATION...Updated at 0500Z.

South Central Arizona including KPHX, KIWA, KSDL, and KDVT; and
Southeast California/Southwest Arizona including KIPL and KBLH:

No weather concerns will exist through Saturday night under clear
skies. Trends in wind speeds and directions will be nearly identical
to the past 24 hours with the typical westerly shift in the Phoenix
metro early/mid afternoon, while N/NW directions will prevail the
majority of the period in SE California.

&&

.FIRE WEATHER...
Warm and dry conditions will persist through the weekend with strong
high pressure quickly building into region by Sunday. Expect breezy
conditions again this afternoon across portions of southeast
California into the Lower CO River Valley before overall light winds
are seen starting Saturday. Low humidities will continue during the
period with MinRHs mainly between 10-15% and fair to poor overnight
recoveries to around 25-30%. Unseasonably warm temperatures are then
forecast for next week while dry conditions persist.

&&

.CLIMATE...

Record high temperatures next week:

Date         Phoenix           Yuma         El Centro
----         -------           ----         ---------
Feb 24      91 in 1904      93 in 1986      92 in 1986
Feb 25      92 in 1921      95 in 1986      94 in 1986
Feb 26      91 in 1986      96 in 1986      95 in 1986
Feb 27      92 in 1986      95 in 1986      96 in 1986
Feb 28      89 in 1986      97 in 1986      92 in 1986

&&

.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...None.
CA...None.

&&

$$

DISCUSSION...Salerno
PREVIOUS DISCUSSION...Kuhlman
AVIATION...18
FIRE WEATHER...Kuhlman
CLIMATE...18