560
FXUS65 KPSR 031927
AFDPSR

Area Forecast Discussion
National Weather Service Phoenix AZ
1227 PM MST Tue Mar 3 2026

.KEY MESSAGES...

- Cooler temperatures, but still remaining 10 degrees above
  normal, can be expected through midweek.

- A dry weather system will bring locally windy conditions on
  Thursday and Friday, while also briefly dropping temperatures
  more into the near normal range.

- There is potential for a stalled out weather system near our
  region this weekend into early week to bring a round of
  precipitation early next week.

&&

.SHORT TERM /TODAY THROUGH WEDNESDAY/...
The latest water vapor satellite imagery as well as objective
analysis show a weakening shortwave trough moving through the
central Rockies with the associated trough axis extending
southwestward through the Desert Southwest. A lingering pressure
gradient on the back side of the trough will result in some
northerly breezes, mainly along the Lower Colorado River Valley,
through this afternoon with peak gusts of 20-30 mph. With a cooler
air mass in place, afternoon high temperatures will be noticeably
cooler compared to the record warmth observed since late last week
as readings are expected to top out in the mid 80s across most of
the lower desert communities. Heading into Wednesday, a transient
upper-level ridge will pass through the region out ahead of the
next troughing feature from the Pacific Northwest that will
influence the weather pattern heading towards the latter half of
the week. The ridge will result in tranquil weather with light
winds and temperatures similar to today.

&&

.LONG TERM /THURSDAY THROUGH MONDAY/...
Model guidance is starting to come into better agreement with the
incoming system later this week, but there are still some
unknowns with its evolution, how long it will stick around, and
whether or not rain chances will be in our future. Guidance seems
to have come to a good consensus with the initial development of
an upper low just to our north late Thursday before a second
piece of energy dives southward into the base of the trough on
Friday. The first piece of energy will not impact our region, but
strong height falls associated with the trough will help to bring
another breezy to windy day on Thursday while highs temperatures
also drop just below 80 degrees. Model uncertainty increases once
the second piece of energy drops into the trough on Friday.
However, there is at least good consensus for this feature to
cause a new upper low to develop somewhere to our southwest by
Friday night into Saturday before likely becoming cut off from the
main flow.

Dry conditions will persist across our region late this week into
the weekend as the disturbances will contain little to no moisture
as they briefly pass through or brush by our region. NBM guidance
has been trending cooler for at least Friday with highs now
potentially only topping out in the lower 70s to around 75
degrees. Uncertainty in the position of the cut-off low this
weekend is impacting the potential range for our forecast
temperatures, but they should at least bounce back into the 80s
if the low moves far enough to our southwest.

Models are suggesting a quick deepening of the low this weekend
as well as it stalling out somewhere near or just west of Baja.
The eventual strength of the low and how long it stalls out will
likely determine how much moisture can get entrained into the
system and whether or not the moisture will get transported into
our region. Model trends over the past couple of days have been
leaning toward a higher probability of at least some modest
moisture advecting into the area Sunday into Monday. This in turn
has led to an increasing number of ensemble members pointing at
some mainly light QPF into the region, focused more across the
southeastern 1/3 of Arizona. NBM PoPs have risen with the latest
run, but chances max out at 20% across the south-central Arizona
lower deserts to 40% over the eastern Arizona high terrain.
Another couple of days of model runs will hopefully result in
decreasing model uncertainty.

&&

.AVIATION...Updated at 1720Z.

South Central Arizona including KPHX, KIWA, KSDL, and KDVT:
No aviation concerns expected during the TAF period. Winds will
follow typical diurnal trends with windows of variability during
directional shifts. Clear skies will give way to SCT-BKN high
clouds during the latter half of the forecast.


Southeast California/Southwest Arizona including KIPL and KBLH:
No major aviation concerns are expected during the next 24 hours.
N`rly winds will prevail at each terminal before directions tilt
back toward the W/NW after sunset. Clear skies this afternoon will
become SCT-BKN early tonight as high clouds stream over the
region.

&&

.FIRE WEATHER...
Temperatures will cool today, but remain well above normal as a
dry weather system passes by to the north. Winds will also be
lighter today except for northerly gusty winds up to 25 mph across
southeast California and the Lower CO River Valley. Overall light
winds are anticipated for Wednesday. MinRHs will continue to range
between 10-15% areawide, followed by fair overnight recoveries
commonly between 30-50%. Another dry weather system later this
week should again bring widespread breezy conditions by Thursday
while dropping highs mostly into the mid to upper 70s.

&&

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

$$

SHORT TERM...Lojero
LONG TERM...Kuhlman
AVIATION...Ryan/Benedict
FIRE WEATHER...Kuhlman