Peoria, Arizona 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

834
FXUS65 KPSR 170550
AFDPSR

Area Forecast Discussion
National Weather Service Phoenix AZ
1050 PM MST Wed Apr 16 2025

.UPDATE...
06Z Aviation Discussion.

&&

.SYNOPSIS...
Near to slightly above normal temperatures will be common this
afternoon before noticeable cooling takes place through the
remainder of the workweek as a weather disturbance traverses the
region. This unsettled period will also result in periods of breezy
to locally windy conditions along with chances for rain showers,
with the best chances confined to the Arizona high terrain. Once
this system exits, a quick warmup back to near and above seasonal
temperatures will ensue.

&&

.DISCUSSION...
Current 500mb analysis reveals a myriad of weather regimes
stretched out across the CONUS, with multiple areas of troughing
over the coasts, and high pressure centered over the the Plains.
Closer to home, we find ourselves in a bit of a transition zone,
with the above-mentioned ridge beginning to push further east,
while a closed upper-low spins just off the Southern California
Coast. This cut-off will slowly inch closer toward the Desert
Southwest over the course of the next few days but as it does,
another shortwave, currently located over southern Canada, will
dive south across the Great Basin. These disturbances will
eventually merge right over Arizona and setup a somewhat
unsettled, but noticeably cooler, end to the workweek.

Before we get to that point however, one more day of near to above
normal temperatures is in store as lower desert highs range from the
mid 80s to lower 90s. The lower end of that range will favor the
deserts of SE California and SW Arizona due to their closer
proximity to the Eastern Pacific low. Regional pressure gradient
enhancement will also result in breezy to locally windy conditions
for portions of our forecast area this evening. Widespread gusts
of 20-25 mph will be common, with higher gusts expected for the
typical downsloping areas in SE California. Due to the high
probabilities (>90%) of seeing gusts exceed 40 mph over the far
southwest corner of Imperial County, a Wind Advisory has been
posted for this area through tonight. It is not out of the
question to see similar gusts further east toward the Imperial
Valley even the Colorado River Valley, but any advisory level
gusts are expected to be sporadic.

As we approach the end of the workweek and the two aforementioned
disturbances merge, a noticeable pattern shift will take place
across the Desert Southwest. Noticeably cooler air will filter in
starting Thursday when afternoon highs will remain below seasonal
values, with highs generally in the middle 70s to lower 80s for a
few spots. Due to the residence time of the newly amplified system,
these cooler-than-normal temps will continue into Friday, when lower
desert high are not expected to make it out of the 70s. Many spots
will be a good 5-10 degrees below normal for this point in April
during this timeframe. Something else that will need to be monitored
will be the potential for rainfall during the period from Friday
into early Saturday. The regional moisture profile will increase,
which will likely be enough to produce some terrain induced
shower activity for areas to the east of the Phoenix metro. One
question that remains is will the cold core and associated
dynamic ascent will reach far enough to spark some shower activity
over lower desert areas of south-central Arizona. At this time,
the global models do not seem to agree on this variable but hi-res
data should provide some clarity over the next day or so. An
enhanced regional pressure gradient will remain in place so more
episodes of breezy to locally windy conditions will persist into
at least Saturday.

Once this system ejects toward the Plains by Saturday, a quick day-
to-day warmup will ensure, with above-normal temperatures returning
by the start of next week. The good news is, positive height
anomalies are not expected to increase to the extent that they did
last week, so triple digit heat is not expected to return during the
next 7-10 days. Quasi-zonal flow will translate to lower desert
highs in the upper 80s to lower 90s and dry conditions as when head
into the latter portion of April.

&&

.AVIATION...Updated at 0545Z.

South Central Arizona including KPHX, KIWA, KSDL, and KDVT:
No major aviation weather concerns are anticipated through the
forecast period. Winds are expected to shift out of the S-SE
overnight at all metro terminals and remain mostly southerly
through sunrise with speeds aob 10 kts. Winds will then return
back out of the WSW at all terminals late tomorrow morning. By
sunrise tomorrow morning, model guidance and forecast soundings
continue to suggest a low cloud deck developing with bases around
4 kft. There is a low chance <30% that this deck will become BKN,
but is more likely to be FEW-SCT and only persist for a few hrs
before scattering out. Otherwise, skies should remain mostly
clear through the period.

Southeast California/Southwest Arizona including KIPL and KBLH:
The main aviation weather concern continues to be strong westerly
winds at KIPL where observed gusts have been as high as 35-40
kts. These stronger gusts should only last for another hour or two
before falling to around 20-30 kts overnight. Winds will be much
lighter at KBLH overnight, but will still remain elevated around
11-15 kts of out of the S-SW. Skies are expected to be mostly
clear at both terminals through the forecast period.

&&

.FIRE WEATHER...
Above normal temperatures will cool to below normal levels during
the latter half of the week as a weather system moves through the
region. Ahead of this system, gusty afternoon winds will be common
today while seasonally low humidity values result in an elevated
fire danger. Cooling temperatures and a modest increase in moisture
will allow humidity levels to gradually increase the remainder of
the week precluding widespread critical thresholds. In general,
minimum afternoon humidity levels in the teens will be common today
with values increasing closer to a 20-30% range during the latter
half of the week. Early next week, warming temperatures and lowering
RH values will return to the districts.

&&

.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...None.
CA...Wind Advisory until 6 AM PDT Thursday for CAZ562.

     Wind Advisory until midnight PDT tonight for CAZ566-567.

&&

$$

DISCUSSION...RW
AVIATION...Salerno
FIRE WEATHER...18