322
FXUS65 KPSR 011034
AFDPSR

Area Forecast Discussion
National Weather Service Phoenix AZ
334 AM MST Wed May 1 2024

.SYNOPSIS...
Above normal temperatures are anticipated through the remainder of
this week with highs reaching the low to mid 90s across the lower
deserts. An upper level trough will swing through the Desert
Southwest late this weekend resulting in breezy to locally windy
conditions and slightly cooler temperatures across southcentral AZ
and southeast CA. Otherwise, dry weather will prevail across the
forecast area through early next week.

&&

.DISCUSSION...
Latest mid-lvl wv imagery and streamline analysis reveals a broad
trough stretching across the western CONUS and dry westerly flow
aloft present over AZ and southeast CA. Amplification of the
northern stream trough will cause mid-lvl hghts/thicknesses to
decrease slightly today, promoting slightly cooler temperatures
than we saw yesterday with lower desert highs reaching the upper
80s to low 90s this afternoon. Very little change in temperatures
is expected across the region on Thursday and Friday as 500 mb
hghts remain steady around 573-574 dam. Clear skies and an uptick
in afternoon breeziness is anticipated through the remainder of
this week, but overall dry and quiescent weather is expected.

As we head into this weekend, ensembles still depict a potent
shortwave trough digging southeast into the Pacific NW on Saturday
and swinging across the Intermountain West on Sunday and Monday.
There is still disagreement amongst the ensembles regarding the
overall progression and depth of this trough with a lower amplitude
and more northerly track suggested by the EPS while the GEFS is
showing a deeper and more southerly route. Despite these
differences, we can expect an increase in winds from this system.
Gusts will likely reach 20-30 mph beginning as early as Saturday
across southeast CA and southwest AZ. Stronger winds will begin to
overspread AZ on Sunday where gusts could reach 25-35 mph across the
lower deserts with 40+ mph in the higher terrain areas. Due to the
negative hght anomalies associated with this trough, temperatures
will cool back down to around normal with highs mainly in the low to
mid 80s on Sunday and Monday. After the trough departs, zonal flow
aloft should return to the forecast area and temperatures will
steadily climb back above normal by the middle of next week.

&&

.AVIATION...Updated at 0500Z.

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

No aviation concerns are anticipated during the TAF period. Winds
will follow typical diurnal tendencies with occasional breezes in
the mid and upper teens during the afternoon hours. An extended
period of S`rly crosswinds can be expected at KPHX during the E to
W transition. Besides a FEW passing clouds over the region later
in the TAF period, skies will be mostly clear.

&&

.FIRE WEATHER...
Warm and dry conditions will persist through the rest of this week
with highs consistently around 3-5 degrees above normal each day
through Saturday. A dry weather system will bring slightly cooler
temperatures to the area on Sunday and Monday. Winds will be light
today with some afternoon breeziness anticipated through Friday,
however there will be a noticeable increase in winds this weekend
with gusts reaching 20-30 mph, locally up to 40 mph in the higher
terrain on Sunday. Minimum relative humidity values will range
from 8-15% each day. Moisture recovery will range from poor to
fair each night, or around 25-50%.

&&

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

$$

DISCUSSION...Salerno
AVIATION...RW
FIRE WEATHER...Salerno/Young