Heber, California 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

968
FXUS65 KPSR 171128
AFDPSR

Area Forecast Discussion
National Weather Service Phoenix AZ
428 AM MST Sun May 17 2026

.UPDATE...Updated Aviation Discussion.

&&

.KEY MESSAGES...

- Widespread breezy to locally windy conditions are expected this
  afternoon through this evening, and will continue tonight
  through early Monday morning across Southeast California
  following a cold front.

- Elevated to locally critical fire weather conditions are
  anticipated for a few hours this afternoon and evening for the
  Eastern Arizona higher terrain, where a Red Flag Warning will be
  in effect.

- Afternoon high temperatures will be near normal today and then
  drop to 4 to 6 degrees below normal for Monday and Tuesday
  before slowly warming back up again.

&&

.SHORT TERM /TODAY THROUGH MONDAY/...
A broad longwave trough remains across the Western CONUS with a
weak shortwave trough seen moving across northern AZ early this
morning. This weak trough contributed to stronger breezes Saturday
afternoon and evening. The pressure gradient across the region
should relax a touch this morning through midday as the shortwave
departs, but another, more potent, shortwave trough will drop
south through NV this afternoon and evening before progressing
eastward across UT and CO Monday morning. This will lead to a re-
strengthening of the pressure gradient and another increase in
winds across the region, especially during the late-afternoon and
evening hours across southern AZ and southeast CA. Widespread
gusts up to 25-35 mph are expected this afternoon through this
evening, with some areas seeing 40+ mph.

Another round of strong westerly downsloping winds is expected in
Imperial County this evening. Downsloping winds Saturday evening
reached 40-50 mph and similar speeds can be expected again this
evening, if not a touch stronger given mountaintop winds are
forecast to be stronger than last evening. A Wind Advisory has
been issued to include the Imperial Valley again this evening. In
addition to the gusty westerly winds, a dry cold front is expected
to drop south through southeast CA and southwest AZ tonight with
rather strong N-NW post-frontal winds, especially across eastern
Riverside County where gusts up to 40-50 mph are possible. Another
Wind Advisory has been issued for eastern Riverside and northeast
Imperial County for the post-frontal winds tonight through early
Monday morning. Of particular concern are strong crosswinds along
I-10, especially between Desert Center and the Indio Valley, where
HREF probabilities of peak wind gusts >50 mph are maximized
(60%). The strong winds will be capable of generating localized
dust channels that could significantly reduce surface visibility.

The gusty winds this afternoon and evening will also once again
lead to elevated and marginally critical fire weather conditions.
A Red Flag Warning remains in effect for southern Gila County and
the Tonto National Forest where afternoon and evening winds are
forecast to be strongest in combination with minimum RHs of 10-15%
and dry fuels.

Aside from the winds, the passing of the shortwave troughs, even
with them staying to the north, and the cold front passage will
cool temperatures down. High temperatures this afternoon are
forecast to be right around seasonal levels in the low to mid 90s
across the lower deserts. Temperatures drop further for Monday
with lower deserts likely failing to reach 90F (NBM probability of
>90F is 10-20%). Skies will be mostly clear to at times partly
cloudy with high clouds today through Monday. There will also be a
narrow band of PBL moisture and forcing along and just ahead of
the cold front Monday morning. Enough to at least lead to some
lower clouds in south-central AZ near sunrise. There are a couple
HREF members producing a few sprinkle showers out of these clouds,
but overall PoP is under 10%.

&&

.LONG TERM /TUESDAY THROUGH SATURDAY/...
As the potent weekend shortwave trough departs the Mountain West,
to drive severe weather in the Plains, a measure of broad
cyclonic flow over the Western U.S. will remain and likely
persist through the remainder of the upcoming work week. Heights
aloft will rebound though, closer to seasonal averages, and so
temperatures are expected to warm through the middle of the week,
with seasonally dry conditions continuing. Meanwhile, a strong
midlevel ridge will remain nearly stationary off the Pacific
Northwest Coast through much of next week, with most global
guidance showing a subtropical jet forming under the ridge and
developing a few weak disturbances. A few of which may be sent
downstream and near/over the Southwest U.S.. Regardless of the
details and how weak troughing over the West- Central CONUS
eventually resolves, essentially all solutions currently show the
region remaining completely dry, with periods of mid-high level
clouds and slowly warming temperatures through the work week.

&&

.AVIATION...Updated at 1120Z.

South Central Arizona including KPHX, KIWA, KSDL, and KDVT:

The main aviation concerns will be a period of elevated cross-
runway winds at KPHX late this morning along with gusty W-SW winds
this afternoon into the evening. Light winds with low confidence
on precise directions, but a general E/SE tendency early this
morning will veer out of the south by 15-17Z, with occasional
gusts into the teens developing. Winds will then go W-SW during
the afternoon with gusts up around 20kt, then further increasing
to around 25kt between 23-01Z and continue through 06-07Z.
Confidence is low that winds will become E-SE tomorrow night at
KPHX and may just stay S-SW, and a period of light winds and
variability cannot be ruled out. Skies will remain mostly clear
through much of the morning with FEW high clouds moving in this
afternoon and evening. A FEW-SCT deck as low as 4 kft AGL may
develop around sunrise Monday morning and diminish out by late
morning.

Southeast California/Southwest Arizona including KIPL and KBLH:

Periods of gusty winds will be the main aviation weather issue
throughout the TAF period. At KIPL, winds will maintain a westerly
component while at KBLH winds will fluctuate from the south to
southwest. Wind speeds will pick up again at KIPL early this
afternoon with gusts of 20-25kt expected. A period of stronger winds
(30-35kt) is again possible in the evening (00-04Z). Brief
visibility restrictions will be possible with the strongest gusts
due to blowing/lofted dust. At KBLH, light southerly and at times
VRB winds this morning will pick up late morning, with gusts around
20 kt beginning during the afternoon hours. A period of higher wind
gusts (around 25kt) is possible during the evening hours (01-05Z). A
front will enter the area from the north northwest and switch winds
abruptly at KBLH overnight.  Skies will remain mostly clear through
most of this morning with FEW high clouds moving in this afternoon
and evening.

&&

.FIRE WEATHER...
Elevated and marginally critical fire weather conditions are
expected this afternoon and evening for a few hours as winds
increase across the region. A Red Flag Warning remains in effect
for southern Gila County and the Tonto National Forest for this
afternoon through this evening. The winds will likely steadily
increase through the afternoon, with peak wire weather conditions
(strongest winds and lowest RH) likely between 1500-2000MST. Wind
gusts in the warned area will peak around 25-35 mph and RH values
will minimize around 10-15%. While RH increases above critical
levels after 2000MST the elevated breezes are likely to continue
through midnight, which may make controlling any new/existing
fires challenging. Wind gusts up to 25-35 mph will be common
across all districts this afternoon, but will be strongest across
southeast CA with westerly sundowner winds in Imperial County up
to 40-50 mph and northerly gusts up to 35-50 mph across much of
eastern Riverside County later tonight through early Monday
following a cold front passage around midnight. There will be
very dry air following the front that will create elevated fire
conditions across Riverside County, even during the overnight
hours. Minimum RH values will be closer to 15-20% across the
western districts. Lingering northerly breeziness down the Lower
Colorado River is expected Monday, but this gradient wind should
weaken heading into the afternoon and winds elsewhere Monday
afternoon will be weaker than today with gusts up to 15-25 mph.
Beyond Monday, weather conditions will be seasonally hot and dry
(Min RHs around 5-15%), with winds mostly reaching up to 15-25
mph in the afternoons.

&&

.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...Red Flag Warning from 11 AM this morning to 11 PM MST this
     evening for AZZ133.

CA...Wind Advisory from 11 PM this evening to 7 AM PDT Monday for
     CAZ560-561-564-568>570.

     Wind Advisory until 1 AM PDT Monday for CAZ562.

     Wind Advisory from 4 PM this afternoon to 11 PM PDT this evening
     for CAZ563-566-567.

&&

$$

SHORT TERM...Benedict
LONG TERM...Benedict/Whittock
AVIATION...Whittock
FIRE WEATHER...Benedict