912
FXUS65 KPSR 092358
AFDPSR

Area Forecast Discussion
National Weather Service Phoenix AZ
458 PM MST Sun Mar 9 2025

.UPDATE...Updated Aviation Discussion.

&&

.SYNOPSIS...
An active weather pattern will occur across the region for the
upcoming week with periodic rain chances and a roller coaster in
temperatures. One more day of dry and warmer conditions expected on
Monday, then our next weather system will move through the region
Tuesday night into Wednesday bringing a good chance of rain and
cooler temperatures. Another, more potent system, will move
through the region Thursday into early Friday with widespread rain
and snow above 3500 feet. Then by next weekend, dry conditions
will return and temperatures will rebound once again.

&&

.DISCUSSION...
Monitoring an active weather pattern that will continue across
the region for the upcoming week. After one more day of dry
conditions and above normal temperatures for Monday, a series of
weather systems will bring periodic precipitation chances and
cooling temperatures for the region beginning late Tuesday and
continuing into Friday.

Upper level ridge axis overhead today will shift east on Monday.
Increasing upper level southwest flow and warm air advection will
push temperatures well above normal for Monday. We will then
transition to the next weather system Tuesday into Wednesday. Closed
upper low as seen on water vapor imagery well off the CA coast
this afternoon will push east and move onshore along the CA/Mexico
border Tuesday. This system is expected to weaken and open up as
the trough moves quickly east across AZ Tuesday night. This system
will not be as strong as last Fridays system, but has enough
upper support and moisture transport to produce a period of
showers for most locations. Lightest amounts will be in SE CA,
increasing into Phoenix and especially the foothills and higher
elevations north and east of the Phoenix, where amounts could be
just under a half inch.

Right behind, we will be honing in on a more potent system moving
in for Thursday and Friday. This system will bring another round
of widespread rainfall with good moisture transport. It will also
be a colder system with snow levels dropping to about 3500 feet.
In addition, this system will bring windy conditions with some
areas seeing gusts 30 to 40 mph. Temperatures will continue to
fall with this system, with valley locations potentially
struggling to reach the 60s. Stay tuned as we fine tune the
specifics as the week progresses.

Upper heights rise again by next weekend for a return to more
seasonal dry and warmer conditions.

&&

.AVIATION...Updated at 2357Z.

South Central Arizona including KPHX, KIWA, KSDL, and KDVT:

Very light winds (aob 5 kts) are expected through tonight. A late
N-NW shift is still anticipated this evening amongst light
variability. Gradient E-SE will increase tomorrow morning and may
lead to occasional gusts up to 15-20 kts for a few hours between
16-19Z. The morning winds will subside heading into the afternoon
and likely veer to a southerly component for much of the
afternoon before another late and brief attempt at W-NW winds. SKC
will prevail.

Southeast California/Southwest Arizona including KIPL and KBLH:

Winds will remain light through the TAF period at both terminals.
Directions will eventually switch to a light W this evening and
tonight at KBLH and KIPL, respectively. Both terminals will also
see extended periods of variability. Similar winds are expected
tomorrow. SKC skies will prevail through most of the TAF period.

&&

.FIRE WEATHER...
No significant fire weather conditions forecast for the upcoming
week despite an active weather pattern. Monday and most of Tuesday
will remain dry with above normal temperatures and relative
humidities bottoming out in the teens. Our next set of weather
systems will impact the area Tuesday night and early Wednesday and
then again Thursday and Friday. These systems will likely produce
additional wetting rains, excellent humidity recoveries, cooler
temperatures and gusty winds. While the Tuesday night system will
be a quick hitter, the Thursday and Friday system will be more
potent and offer up more precipitation and gustier winds. By
Thursday and Friday accumulating snowfall is also expected above
3500 feet. Winds will be strongest on Thursday with gusts 30 to 40
mph.

&&

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

$$

DISCUSSION...Frieders
AVIATION...Benedict
FIRE WEATHER...Frieders