Forecast Discussion for PSR NWS Office
441
FXUS65 KPSR 142351
AFDPSR
Area Forecast Discussion
National Weather Service Phoenix AZ
451 PM MST Fri Feb 14 2025
.UPDATE...Updated Aviation Discussion.
&&
.SYNOPSIS...
As a weather disturbance clears the region tonight, drier conditions
will return over the weekend as temperatures moderate towards the
seasonal normal. Very tranquil weather will settle over the area
next week with additional warming pushing readings into an above
normal range.
&&
.DISCUSSION...
As broad troughing moves inland over the western Conus, a decaying
cold front has slid into south-central Arizona this afternoon
becoming the focus for scattered showers. A cyclonic jet core
slicing through the forecast area combined with a shortwave diving
into the trough base from the northwest were creating modest forced
ascent over the region, however the loss of better quality deep
moisture surrounding these features was significantly limiting
precipitation coverage. While a few additional isolated showers will
be possible around and east of the Phoenix metro late this afternoon
and evening working off residual moisture and continued favorable
ascent, shortwave and trough passage overnight will quickly
introduce height rises, deep layer subsidence, and clearing skies.
Forecast confidence through next week is excellent given very low
ensemble spread as the hemispheric pattern locks into a general
eastern Conus troughing and western ridging configuration. The
midtropospheric pattern over the Southwest will feature oscillation
between quasi-zonal and northwest flow as H5 heights generally hover
in a 572-576dm range. However within the periods of NW flow, models
continue to advertise at least one low amplitude shortwave passage
Tuesday acting to briefly dampen heights aloft and temper a
prolonged warming trend. Nevertheless, guidance spread is quite
narrow with very good confidence of temperatures warming 4F-8F above
normal during the first half of the week. Another very similar
shortwave should traverse the four corners Friday with only modest
height falls and limited impacts on temperatures. Just beyond the
forecast period, ensemble members are in remarkable agreement
depicting pronounced positive height anomalies building across
portions of the East Pacific and western Conus. It would not be out
of the question for H5 heights to eclipse 582dm next weekend, and
guidance indicates around a 25% chance of flirting with daily record
highs.
&&
.AVIATION...Updated at 2348Z.
South Central Arizona including KPHX, KIWA, KSDL, and KDVT:
The primary aviation weather concern will be the continued lower
CIGs for the beginning of the period. SCT to occasionally BKN bases
aoa 6 kft are expected to continue into the first part of this
evening, with a few vicinity showers near the terminals, before
clouds begin to clear out of the area later this evening. Breezy
westerly winds, with gusts upwards of 20-25 kts, will taper off
this evening, but confidence is low that KPHX will see a typical
diurnal easterly switch overnight tonight. At this time, expect
light and variable winds overnight at KPHX before switching back
to the west Saturday morning.
Southeast California/Southwest Arizona including KIPL and KBLH:
Strong westerly winds will be the primary aviation weather concern
through the first part of the TAF period. Gusts upwards of 25-30
kts will continue at the terminals into this evening before
subsiding. May see some blowing dust get generated with these
winds, primarily at KIPL, but expect VFR visibilities to persist.
Westerly winds will continue through the overnight period before
switching to the NNW at the terminals around 16-17Z. FEW-SCT decks
aoa 7-8 kft will continue to diminish with only some passing high
clouds prevailing thereafter.
&&
.FIRE WEATHER...
Light shower activity will move through the eastern districts today,
with wetting rain chances are generally under 20% across the lower
deserts to upwards of 40-70% across the Arizona higher terrain into
this evening. MinRHs will remain elevated at 30-50% through today
before quickly dropping into the teens by Sunday. Expect breezy to
locally windy conditions across the region today, before subsiding
this evening. High pressure will then push into the region over the
weekend leading to drier and warmer conditions, lasting through at
least early next week.
&&
.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...None.
CA...Wind Advisory until 4 AM PST Saturday for CAZ562.
&&
$$
DISCUSSION...18
AVIATION...Smith
FIRE WEATHER...Young/Kuhlman
NWS PSR Office Area Forecast Discussion
|