102
FXUS65 KPSR 300502
AFDPSR

Area Forecast Discussion
National Weather Service Phoenix AZ
1002 PM MST Mon Jun 29 2026

.UPDATE...Updated 06z Aviation Discussion...

&&

.KEY MESSAGES...

- Lingering breezy conditions coupled with low humidity and very
  dry fuels through Tuesday will result in elevated fire danger,
  primarily for the Arizona higher terrain.

- Below normal temperatures will prevail through much of the week.

- More tranquil conditions and a slow warming trend will arrive
  during the latter half of the work week.

&&

.SHORT TERM /TODAY THROUGH WEDNESDAY/...
An unusually high amplitude, broad upper level trough for late
June has settled over the Western US, with several shortwave
impulses apparent in midlevel water vapor satellite imagery
embedded within the broader trough. One of which is gradually
shifting northeastward into the Northern Plains, packing heights
aloft along its eastern flank to induce a fairly prominent SSW-
NNE oriented jet streak. As this first shortwave departs, midlevel
flow will decrease somewhat today but remain elevated, resulting
in lingering breezy to locally windy conditions. A second impulse
can been seen moving south along the California coast and is
forecast to round the base of the longwave trough, passing just
northwest of the area and then ejecting northeastward late
Tuesday. This will reinvigorate midlevel flow, maintaining the
widespread gusty afternoon winds on Tuesday, primarily over
Northern/Eastern AZ high terrain, but not to the same extent as
was observed over the weekend. The continued unusually strong
synoptic winds will promote elevated fire danger over the AZ high
terrain east/northeast of Phoenix through at least Tuesday, then
winds taper off more notably by the latter half of the week.

Confidence remains high that broad troughing will be maintained
over the Western US through much of the rest of the week, but with
negative midlevel height anomalies gradually eroding and
retreating northward. Ensemble mean H5 heights through early
Wednesday should fluctuate within a 579-585 dam range over the
forecast area, mostly between the 3rd and 10th percentiles of
climatology, supporting temperatures well below normal for late
June/early July. As we enter our climatologically hottest time of
the year, expect afternoon highs to struggle to reach the triple
digits across much of the lower deserts through Wednesday (except
in urban, low-lying valley areas), between 5 and 10 degrees below
daily normals. Perhaps more impressively, the column is forecast
to dry out even further heading into the middle of the week with
the second shortwave impulse passing north of the area, resulting
in PWATS as low as 0.2-0.3" and surface dewpoint temperatures in
the 20s and 30s across portions of the forecast area. Forecast
lows Tuesday and Wednesday morning are in excess of 10F below
daily normals for some rural lower desert communities, cooling
well into the 60s.

&&

.LONG TERM /THURSDAY THROUGH SUNDAY/...
Ensemble model guidance remains in good agreement on the overall
synoptic pattern starting to shift by the latter half of this week.
They show high pressure slowly starting to push back into the Desert
Southwest from the east and the Pacific trough lifting
north/northeastward. As a result, H5 heights aloft will start to
increase leading to a gradual warming trend. The latest NBM has
temperatures returning to near to slightly below normal by the end
of the workweek. The high pressure will continue to push into our
region next weekend with H5 heights aloft continuing to rise. The
NBM has afternoon high temperatures going back above normal by the
end of the weekend, with highs in the 105-110 degree range.

With high pressure slowly building back into our region more
tranquil weather conditions are expected with only some minor
afternoon breezy conditions expected with the highest winds across
the Lower CO River Valley and the higher terrain north and east of
Phoenix. Very dry conditions will also remain in place and thus
there will be no rainfall chances through this weekend.

&&

.AVIATION...Updated at 0500Z.

South Central Arizona including KPHX, KIWA, KSDL, and KDVT:
No major aviation weather concerns under clear skies can be
expected throughout the TAF period. The overall wind pattern will
follow the typical diurnal tendencies with a period of southerly
winds during the late morning/early afternoon before the westerly
shift. Some occasional gusts near 20 kts can be expected once
again Tuesday afternoon/early evening.

Southeast California/Southwest Arizona including KIPL and KBLH:
No major aviation weather concerns under clear skies can be
expected throughout the TAF period. At KIPL, winds will generally
be out of the west while at KBLH, winds will fluctuate between the
south-southeast to southwest. Another round of afternoon/early
evening gusts between 20-25 kts can be expected, strongest at
KIPL.

&&

.FIRE WEATHER...
Elevated fire danger, and locally near critical for the high
terrain of the eastern district, will continue through Tuesday
due to low humidity, very warm temperatures, breezy southwest
winds during the afternoons/early evenings, and very receptive dry
fuels. Afternoon minimum humidities between 7-15% through Tuesday
will drop to a 5-10% range for the eastern districts beginning
Wednesday and areawide by Friday. Poor to fair overnight
recoveries between 20-45% through Wednesday night will decrease
into a 15-30% range Thursday night onwards. Winds will diminish
more noticeably during the latter half of the work week, but
afternoon/early evening upslope and upvalley gusts to 15-25 mph
will continue. Temperatures will remain below normal through the
majority of the week, with lower desert highs around 100F through
midweek, then gradually warming into a near normal range this
weekend.

&&

.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...None.
CA...Wind Advisory until 8 AM PDT Tuesday for CAZ562.

&&

$$

SHORT TERM...Whittock
LONG TERM...Berislavich
AVIATION...Lojero
FIRE WEATHER...Whittock/Berislavich