000
FXUS65 KPSR 071101
AFDPSR

Area Forecast Discussion
National Weather Service Phoenix AZ
401 AM MST Wed Jun 7 2023

.UPDATE...Updated Aviation Discussion...

&&

.SYNOPSIS...
Dry and tranquil conditions are expected over the next several
days. Under the influence of a troughing pattern, temperatures
will run below normal, with daytime highs in the 90s and
overnight lows in the 60s to lower 70s through at least the start
of next week.

&&

.DISCUSSION...
Water vapor imagery at this hour continues to show an upper-level
low spinning over central California, which helped bring "cooler"
temperatures and breezy to windy conditions to our region
yesterday. Global ensemble runs indicate this system hovering
over California for the next few days, which will help keep much
of the Desert Southwest under the influence of a troughing
pattern. Temperatures in response to this pattern are expected to
run below normal over our CWA, with forecasted highs in the mid
90s today and Thursday. The vast majority of the region will
remain dry today, but a quick shower cannot be ruled out around
Joshua Tree NP as PoPs stand at 15-25% for the afternoon hours.
Overnight temperatures will be quite comfortable for the next
several days with lows in the mid 60s for Yuma and El Centro, with
Phoenix falling to the lower 70s.

Going into the latter part of this week, the aforementioned system
over California shows signs of weakening according to global
ensembles. This should allow our H5 heights to rebound, which in
turn will allow our temperatures to rebound slightly. However,
troughing is expected to persist, which will continue to keep
temperatures below normal through the start of the weekend. NBM
MaxT has upper 90s for the lower deserts on Friday, and a chance
(40-50%) of a brief return to the triple digits for Phoenix on
Saturday. Models are in good agreement of another upper-level low
beginning to approach our CWA by Sunday. This system is expected
to reinforce cooler than normal conditions and usher in the return
of breezy to windy conditons for most of the desert southwest.
Daytime highs for Monday and Tuesday are currently forecasted to
run 7-10 degrees below normal.

Looking ahead further into next week, there are signs of a ridge
building across central Mexico and the Southern Plains in the
long range guidance. However, it is too early to tell if this
ridge will move far enough west to affect our region. If this
were to move its way far enough west and influence conditons over
our region, closer to normal temperatures would be expected to
return coupled with the continuation of dry conditions.

&&

.AVIATION...Updated at 1100Z.

South-Central Arizona including KPHX, KIWA, KSDL, and KDVT:
Wind forecasts will be the main weather issue through tonight
under mostly clear skies. Confidence remains good that wind
directions and speeds will behave very similar to the past 24
hours. During the conversion back to a W/SW direction this
afternoon, speeds will be somewhat weaker than yesterday
afternoon with less overall gustiness.

Southeast California/Southwest Arizona including KIPL and KBLH:
Little to no aviation impacts expected through tonight under
mostly clear skies. A W/SW component will be favored at KIPL
through the period with some variability in direction possible
later this morning into the afternoon. Winds at KBLH will favor
the S/SW with some minor gustiness during the afternoon.

&&

.FIRE WEATHER...
No major fire weather concerns are expected through the end of this
week as winds will return to a more typical pattern with daytime
breezes and gusts generally topping out at around 20 mph and
temperatures remaining below normal. RHs are expected to remain
quite low, bottoming out each day mainly in the 5-15% range through
at least Saturday. Overnight recovery will be minimal in the eastern
districts as MaxRH values will mainly range 25-40% Wednesday night,
decreasing to 20-35% Thursday night. Slightly more modest recovery
is expected in the western districts as MaxRH values should range 35-
50% for the next few nights. These dry conditions will continue to
prevail for the foreseeable future.

&&

.HYDROLOGY...Updated 255 PM MST 6/6/2023

GILA: Releases from Painted Rock Dam continue to remain above 1,000
cfs, leading to extended downstream impacts along the Gila River.
Impacts include continued inundation of unbridged river crossings,
with many of these remaining closed. Therefore, the Flood Warnings
along the Gila River between Painted Rock Dam and the Colorado River
have been extended through June 13th.

&&

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

&&

$$

DISCUSSION...Smith/RW
AVIATION...18/Kuhlman
FIRE WEATHER...Smith/RW
HYDROLOGY...Smith