547
FXUS65 KPSR 141606
AFDPSR

Area Forecast Discussion
National Weather Service Phoenix AZ
906 AM MST Wed May 14 2025

.UPDATE...Updated 18Z Aviation Discussion.

&&

.SYNOPSIS...
A weather system passing through the region will deliver below
normal temperatures areawide today before warming back to near
normal readings for the end of the workweek. Another dry weather
system will sweep into the Southwest early next week yielding
another round of gusty winds and cooler than normal temperatures.

&&

.DISCUSSION...
Objective analysis this morning shows the trough that has led to
gusty winds across the region over the past couple of days currently
propagating eastward through the Intermountain West. Winds will be
much lighter across the area today as gradients relax and the
greater wind energy aloft shifts east. There will be some lingering
gustiness that is expected to pick up later this morning across
eastern portions of the state, including southern Gila County where
gusts may climb upwards of 20-30 mph. Elsewhere across the forecast
area, typical afternoon breezes gusting upwards of 15-25 mph at
times can be expected. The more notable sensible weather for today
will be the cooler temperatures that will prevail as the trough
axis passes through Arizona with the main cold core remaining
well north of the area. Forecast highs only top out in the mid to
upper 80s for this afternoon across the lower deserts as 500 mb
heights bottom out around 568-572 dm. However, these cooler than
normal temperatures don`t stick around for long as the trough
ejects into the Plains later tonight with broad cyclonic/quasi-
zonal flow prevailing across the southwest CONUS for the end of
the workweek. Heights will gradually recover during this time and
will allow for temperatures to return near normal readings
Thursday as lower elevation highs warm into the upper 80s to lower
90s.

Forecast uncertainty then increases as we head into the start of
next week with the arrival of our next trough. Ensemble clusters
reveal continued discrepancies amongst ensemble membership related
to the the depth of the trough. This uncertainty is reflected in
the NBM temperature IQR with a roughly 6-8 degree spread in high
temperatures by Sunday. Regardless of these uncertainties, there
is good agreement amongst ensembles that we will once again see
below normal temperatures along with another period of strong
winds. If current trends hold, Wind Advisories will likely be
needed once again for this weekend, primarily across parts of
Imperial County. Following the passage of this trough, there is
decent ensemble agreement that ridging will begin to build into
the region with temperatures returning near to above normal by the
middle part of next week.

&&

.AVIATION...Updated at 1605Z.

South Central Arizona including KPHX, KIWA, KSDL, KDVT:
Winds will follow their typical diurnal tendencies through the TAF
period. Current westerly winds will have their typical shift to
easterly during the late evening/overnight hours, with a shift
back westerly tomorrow afternoon. Wind speeds will be elevated
this afternoon and early evening with some occasional gusts into
the teens. Otherwise, wind speeds will generally be aob 8 kt.
Skies will be mostly clear.

Southeast California/Southwest Arizona including KIPL and KBLH:
Winds, at both TAF sites, will be northwesterly through the
afternoon before going westerly this evening. Wind speeds at KIPL
will generally be aob 10 kt. At KBLH, winds will gust into the
teens through the majority of the afternoon, then afterwards
speeds will decrease to aob 8 through the remainder of the period.
Skies will be mostly clear.

&&

.FIRE WEATHER...
Weakening wind speeds and cooling temperatures will reduce the fire
danger the next several days, however another incoming system will
allow winds to strengthen again over the weekend. Under more typical
springtime upslope gustiness with gusts up to 15-25 mph, minimum
humidity values will fall into the 10-15% range the next several
days following poor to fair overnight recovery of 25-50%. Gusty
winds will materialize again this weekend with the next weather
disturbance, however cooling temperatures and increased humidity
levels may preclude widespread critical conditions. At this time,
Saturday afternoon poses the greatest threat of an elevated fire
danger.

&&

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

$$

DISCUSSION...Smith
AVIATION...Berislavich
FIRE WEATHER...Smith/18