-- Discussion containing changed information from previous version are highlighted. --
096
FXUS65 KPSR 211735
AFDPSR

Area Forecast Discussion
National Weather Service Phoenix AZ
1035 AM MST Tue May 21 2024

.UPDATE...Updated Aviation Discussion...

&&

.SYNOPSIS...
Typical dry late-May weather will persist through the remainder
of this week and this weekend, with near normal temperatures each
day as lower desert highs reach the nineties. Typical daily
breeziness in the afternoons can be expected. A weak disturbance
late this week will bring a slight enhancement to the winds and
cool temperatures slightly. By early next week temperatures will
warm to above normal as high pressure develops.

&&

.DISCUSSION...
Global ensemble models maintain strong agreement in the
persistence of a longwave trough pattern across the Western CONUS
through the remainder of this week and this weekend, with a few
embedded dry shortwave troughs, but no substantial weather impacts.
H5 heights are expected to remain around 576-580dm over the area
which is typical for this time of year. So, for the 6 days fairly
typical dry Spring weather is expected across the Desert
Southwest. This will include daily widespread Minor HeatRisk, with
afternoon lower desert high temperatures in the 90s, right at
seasonal normals, plenty of sun, and overnight lows in the 60s.
Typical afternoon breeziness can be expected, with most days
gusting into the 15-30 mph range across the southern deserts.
Slight enhancements to the wind are possible with passing
shortwaves. Currently, the strongest/deepest wave looks to impact
the region Friday and Saturday, with potential for stronger wind
gusts, including in excess of 35 mph in Southeast CA. Following
the shortwave late this week and this weekend, global ensembles
are strongly in favor of a high-amplitude ridge developing across
the Western CONUS heading into early next week, with H5 heights
climbing up to the 585-590dm range. This will lead to 100 degree
afternoon temperatures again and potentially the hottest
temperatures of the year so far.

&&

.AVIATION...
-- Changed Discussion --
Updated at 1735Z.

South-Central Arizona including KPHX, KIWA, KSDL, and KDVT:
VFR conditions are expected through the forecast period with
fairly light winds generally following diurnal tendencies. Expect
southwest winds to establish by the afternoon with occasional
gusts into the mid teens through early evening. Expect a shift to
easterly winds this evening. Clear skies will prevail through the
period.

Southeast California/Southwest Arizona including KIPL and KBLH:
VFR conditions will prevail through the next 24 hours under clear
skies. At KIPL winds continue to favor the west northwest with an
extended period of light wind speeds (aob 6 kt sustained)
increasing later this evening to aob 10 kt sustained. Expect light
and variable conditions tomorrow morning. Light and variable
winds are forecast at KBLH through the afternoon before settling
out of the southwest during the evening becoming light and
variable again tomorrow morning.
-- End Changed Discussion --

&&

.FIRE WEATHER...
Very typical mid/late May weather will prevail the remainder of the
week highlighted by seasonably warm temperatures, dry conditions,
and frequently breezy afternoon/early evenings. Minimum afternoon
humidity levels will mostly fall into the single digits with some
modest improvement into a 10-20% level towards the end of the week.
This will follow generally poor to fair overnight recovery of 20-
40%. Wind gusts 15-25 mph will be common through the week. A
slight enhancement is anticipated during the late-week timeframe
as a dry system moves through. Wind gusts with the late-week
system may increase up to 25-30 mph, to as high as 30-40 mph near
terrain features, and the Imperial Valley, resulting in an
elevated, to perhaps locally critical, fire danger.

&&

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

$$

DISCUSSION...Benedict
AVIATION...95
FIRE WEATHER...18/Benedict