Palo Verde, California 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

651
FXUS65 KPSR 211127
AFDPSR

Area Forecast Discussion
National Weather Service Phoenix AZ
427 AM MST Sat Jun 21 2025

.UPDATE...Updated 12Z Aviation Discussion.

&&

.KEY MESSAGES...

- Widespread breezy to locally windy conditions today and tonight,
  with peak wind up to 25 to 35 miles per hour most places and 40
  plus miles per hour in parts of Southeast California.

- A Red Flag Warning remains in effect through this evening for
  higher terrain areas north and east of Phoenix, with widespread
  elevated to locally critical fire weather conditions due to very
  dry and breezy conditions to go with dry fuels.

- Temperatures cool to below normal Sunday and remain below normal
  through at least the first half of next week.

- Slight chances (10 to 20 percent) for afternoon storms in parts
  of Southern Gila County beginning Tuesday.

&&

.DISCUSSION...
Persistent dry southwest flow will continue across the Desert
Southwest while high pressure ridging remains well off to the
east, in central and eastern portions of the CONUS. WV satellite
shows a low pressure system continues to spin over the PacNW, also
aiding in the southwest flow. A shortwave trough seen on the
western flank of the low early this morning will help dig the
longwave trough closer to the Desert Southwest today and by doing
so will tighten the pressure gradient, leading to slightly
stronger winds than yesterday. Widespread elevated to locally
critical fire weather conditions are expected again today as a
result. The high pressure ridge will also strengthen today and
shift more over the eastern CONUS, leading to significant heat
across the Midwest, Mississippi Valley and Northeast. In a long-
wave pattern like this during the summer, when the eastern CONUS
is roasting under a 596-598dam high, the west is seeing a
reprieve. Negative 500mb height anomalies will spread across the
Desert Southwest this weekend leading to a downtrend in
temperatures.

Widespread breezy to locally windy conditions this afternoon
through this evening and the widespread elevated to locally
critical fire weather conditions will be the primary sensible
weather impact today. The latest HREF supports high probabilities
(>70%) for peak wind gusts in excess of 25 mph this afternoon and
evening across Southern AZ and SoCal. While peak gusts are
expected to stay below 35 mph for most areas, there are high
probabilities for advisory- level wind gusts (>40 mph) this
evening/tonight in western Imperial County CA with westerly
downsloping winds. A Wind Advisory is in effect for this area and
while the advised area does not include the Imperial Valley at
this time this does not mean that winds may not reach advisory
level. Confidence is not quite high enough at this time. There is
also potential for strong 40+ mph northwesterly winds tonight
across Eastern Riverside County CA behind a dry cold front,
coinciding with the passing of the shortwave trough to the north,
but these stronger winds are most likely to occur over the higher
mountain peaks/ridges, and considering less mixing during the
overnight hours a Wind Advisory was not issued. Winds region- wide
will be much lighter on Sunday as the pressure gradient relaxes
with the shortwave trough lifting away.

Temperatures today are forecast to be right around to slightly
below seasonal levels, with lower desert highs around 100-105F.
Sunday is then forecast to be the coolest day in the 7-day
forecast, as the aforementioned shortwave trough swings by to the
north tonight and 500mb heights hit a minimum around 582-584dam
(around the 25th percentile for this time of year). Most lower
desert locations will struggle to reach 100 degrees Sunday
afternoon which is not very common for late-June. Phoenix has only
observed a sub-100 degree high 7 times between June 20th-30th
during the 2000s (Yuma 11 times & El Centro 13 times). While not
as hot as the previous several days, the forecast temperatures
will result in widespread Minor HeatRisk and with ample sunshine,
everyone should continue to exercise caution and protect
themselves and others from the heat, especially with any long
exposure.

Heading into early next week the broad troughing across the west
will linger, and continue the dry southwest flow, but will
gradually weaken and mostly break down by the middle of the week.
By the second half of next week the mid-level synoptic flow
pattern across the Desert Southwest and Northern Mexico is shown
by global models to become pretty weak and disorganized. Most
global ensembles have mean 500mb winds dropping from 20-30 kts to
around 10 kts. For the 500mb wind direction, the ensemble spread
increases considerably, but still with a mean S-SW component.
This pattern outlook will allow for a gradual rise in 500mb
heights, and thus a gradual rise in temperatures with above normal
temperatures and Moderate HeatRisk making a return by the end of
next week.

Where is the monsoon moisture? Global ensemble members continue
to show a battle between dry air over most of AZ and more moist
monsoon conditions to the east and southeast beginning around
Tuesday. The aforementioned trough across the west will work to
keep dry air and southwesterly flow in place, at least over SE CA
and western AZ. But, some deep moisture over northern Mexico looks
to make its way into SE AZ. This moisture, in combination with
upper level support, could lead to some isolated to scattered
thunderstorms beginning around Tuesday. This supports some low end
chances for showers and storms as far north as the White
Mountains and into Gila County. Global ensemble members show this
moisture hanging around through the week, which the current NBM is
showing as daily low-end thunderstorm chances for this area,
while the rest of AZ will more likely have to wait until at least
early-July. Still, it will be worth paying more attention to the
thunderstorm activity to the east toward the end of the week when
the mid-level flow weakens. Perhaps storm activity will trend a
little closer and thunderstorm outflows will start making a push
toward the Valley.

&&

.AVIATION...Updated at 1125Z.

South Central Arizona including KPHX, KIWA, KSDL, KDVT:
Some gusty southwesterly winds during the afternoon/early evening
hours Saturday will be the main aviation weather issue under clear
skies. SOutheasterly winds with speeds generally aob 10 kt will
continue through the mid-morning. By the mid-morning, winds will
be come southerly and pick up speed into the low teens with some
occasional gusts into the upper teens possible by the late morning
hours. Then, during the early afternoon winds will become
southwesterly with gusts of 20-25 kt continue through sunset.
Winds will then go back southeasterly overnight, with speeds aob
10 kt.

Southeast California/Southwest Arizona including KIPL and KBLH:
Gusty winds will continue to be the main aviation weather concern
once again during the afternoon/early evening hours Saturday under
clear skies. Winds at KIPL will be mainly out of the west through
most of the period while winds at KBLH will fluctuate between the
south and southwest. Wind speeds through the mid-morning will
continue to be under 15 kts before speeds increase during the late
morning and afternoon/evening hours with peak gusts upwards of
25-30 kts, with the potential that KIPL occasionally exceeds 30
kts. Some reduced visibilities, but likely remaining P6SM, due to
haze from lofted smoke from a wildfire in Mexico will still be
possible at times at KIPL.

&&

.FIRE WEATHER...
A Red Flag Warning remains in effect through this evening across
the higher terrain to the north and east of Phoenix where periods
of critical conditions will exist. Winds will be 5-10 mph higher
this afternoon and evening across all districts, compared to
yesterday. This will lead to widespread elevated fire weather
conditions and even periods of locally critical conditions
elsewhere, most notably in western Maricopa, central Pinal,
eastern Riverside, and northwest La Paz counties. Expect a
combination of low humidities from 5 to 15 percent, dry fuels with
ERCs around the 97th percentile, and late day gusty winds that
will range from 25-35 mph most places 35-45 mph in western
Imperial County. Sunday through next week winds will be much
lighter, with more typical afternoon breezes, and thus there will
be less wildfire spreading concerns. Conditions though will remain
dry, with daily minRHs mostly at or below 15% with overnight
recoveries only into the 20 to 40 percent range. Near to below
normal temperatures are expected today through the first half of
next week.

&&

.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...Red Flag Warning until 8 PM MST this evening for AZZ133.

CA...Wind Advisory until 11 PM PDT this evening for CAZ562-566.

&&

$$

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