365
FXUS65 KPSR 272118
AFDPSR

Area Forecast Discussion
National Weather Service Phoenix AZ
218 PM MST Sat Apr 27 2024

.SYNOPSIS...
A departing weather system will result in residual breeziness and
some showers across the higher terrain areas of northern and eastern
AZ today. Higher pressure will follow the departing system and
persist through much of next week, resulting in benign weather
pattern. Lower desert temperatures will warm back into the
nineties by Monday and likely persist in the nineties each day
through the week. No rain is in the forecast following today and
winds will be lighter.

&&

.DISCUSSION...
The upper low circulation which brought yesterday`s windy
conditions and evening thunderstorms in now pushing into Colorado
early this afternoon. This potent low and strong upper level jet
around its southern half is helping drive a Plains severe weather
outbreak. Back here in the southern deserts, the low is still
close enough to create some breezy conditions today. Not nearly as
strong as yesterday, but still with some peak gusts up to 20-30
mph this afternoon. There is also still sufficient moisture and
minimal but high enough instability for surface-based convection
to develop this afternoon through this evening. Activity should
remain confined to the northern AZ high terrain, but with the
northwest flow a few showers and maybe a storm could drift into
parts of NE Maricopa and S Gila counties. Impacts from the
convection, should any make it into Maricopa and S. Gila counties
will likely be limited, few hundredths of an inch of rain, gusty
winds, and small hail.

The height field will rise Sunday into Monday as troffing is
replaced by quasi-zonal flow. This will result in warming
temperatures, with highs going from low to mid 80s today, back to
near normal Sunday, and then back into the low to mid 90s Monday.
The temperatures and overall weather through all of next week will
be mostly steady-state, with very little day-to-day changes.
Lower desert highs are forecast to continue to reach the low to
mid 90s each day, with overnight/morning lows in the 60s. These
temperatures will lead to daily widespread minor HeatRisk. No
rain is in the forecast and skies will be mostly clear. Winds
will also be lighter most days, with typical afternoon 15-20 mph
gusts. Beyond Wednesday however, global ensembles show a lot of
uncertainty regarding a deeper trough pattern in the west. There
is at least strong agreement that the core of the trough pattern
will remain well to the north, mainly through the Great Basin,
but uncertainty in the amplitude of the longwave trough pattern
and uncertainty in timing of potential shortwaves will affect
potential for some gustier conditions mid to late week and could
have a slight impact on temperatures.

&&

.AVIATION...Updated at 1758Z.

South-Central Arizona including KPHX, KIWA, KSDL, and KDVT:
No major aviation weather concerns are expected through the TAF
period. Westerly winds will become increasingly breezy going through
afternoon with gusts to 20 kts. Gusts subside during the evening
hours with more typical diurnal tendencies returning overnight. Rain
chances today will remain across the northern high terrain while dry
conditions prevail across the Valley. FEW-SCT clouds around 9-10 kft
will continue through the evening.

Southeast California/Southwest Arizona including KIPL and KBLH:
No major aviation weather concerns are expected through the next
24 hours. Winds at both TAF sites will favor a W to WNW component
through the period with a few afternoon/evening gusts to around
15-20 kts. Mostly clear skies will continue.

&&

.FIRE WEATHER...
Residual breeziness from a departing weather system can be
expected for today with afternoon and early evening gusts ranging
between 20-30 mph. Some showers may affect the far eastern
districts later today, but with minimal impacts. MinRHs will
range between 15-20% across the lower deserts to 30-40% across the
far eastern districts. A significant warming trend takes place
Sunday through early next week with little change in temperatures
expected by the middle to latter of next week. With the warming
temperatures, MinRHs will generally range between 7-15%. Winds
beginning Sunday and continuing through most of next week will be
lighter with typical afternoon upslope breeziness expected. There
is potential for some increased breeziness toward the latter half
of next week with a system(s) passing well to the north, but
confidence is still low at this time.


&&

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

$$

DISCUSSION...Benedict
AVIATION...Smith
FIRE WEATHER...Benedict/Lojero