Casa Grande, Arizona 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

421
FXUS65 KPSR 192322
AFDPSR

Area Forecast Discussion
National Weather Service Phoenix AZ
422 PM MST Fri Jun 19 2026

.UPDATE...Updated 00z Aviation Discussion...

&&

.KEY MESSAGES...

- Temperatures will remain near seasonal levels through Monday
  under clear to mostly clear skies.

- Strong high pressure will gradually build back into the region
  by the middle of next week pushing daytime highs to around or
  just above 110 degrees across the lower deserts.

- Minor to Moderate Heat Risk is forecast through early next week
  before shifting to widespread Moderate to localized Major Heat
  Risk during the latter half of next week.

&&

.SHORT TERM /TODAY THROUGH SUNDAY/...
Latest mid-lvl wv imagery and 500 mb streamline analysis reveals
broad troughing over the E Pacific while a low amplitude ridge is
centered over the southern Rockies and New Mexico. The entire state
of Arizona is now under W to SW flow aloft allowing notably drier
air to overspread our forecast area. This dry air is also readily
apparent in the 12Z KPHX RAOB with an observed PWAT value of 0.57".
Sfc dew points have also decreased significantly into the upper 20s
to lower 30s across the region. Coincidentally, chances of any
convection developing this afternoon is essentially zero and even
mountain cumulus development will be completely eliminated with
clear skies expected over the entire state.

As large scale troughing begins to overspread the forecast area,
heights aloft will decrease to a near normal range over the weekend,
resulting in highs right around normal in a 100-106 degree range
today through Sunday. Overnight lows will also be noticeably
cooler due to the lower humidities and mostly clear skies which
will lead to efficient radiational cooling. Most locations will
see lows in the 70s through the weekend with more rural lower
desert locations potentially dipping into the mid to upper 60s.
The HeatRisk across the area will drop fully into the Minor
category for this weekend.

&&

.LONG TERM /MONDAY THROUGH THURSDAY/...
The upper level trough is forecast to break down and shift to our
northeast starting early next week. As this occurs, the
subtropical high centered just to our south will start to shift
northward while also beginning to strengthen. Currently, model
guidance favors the high center reaching southern Arizona by next
Tuesday with H5 heights rising to around 595dm. This will allow
for a warming trend to commence starting Monday with daytime highs
as warm as 110 degrees by Tuesday.

Models also mostly suggest the high center setting up over or near
southeast Arizona starting Tuesday and staying in that general
vicinity through midweek. This positioning should allow for some
modest Gulf of California moisture surges for a few days next
week with forecast surface dew points gradually increasing back
into the 40s to maybe the mid 50s. However, even with the modest
increase in lower level moisture it will fall short of what would
be needed for any convection to form. The close proximity of the
high center and its strength will keep the subsidence quite strong
next week, basically keeping a lid on any potential convection.

Guidance shows the ridge peaking at around 596-598dm next
Wednesday and Thursday with daytime highs expected to break 110
degrees both days and some locations potentially reaching 115
degrees. Widespread Moderate HeatRisk will develop as early as
Tuesday with a high probability of localized areas of Major
HeatRisk for at least next Wednesday and Thursday. Guidance then
favors another trough passing by to our north by next Friday or
Saturday, likely dampening the ridge and starting a slight cooling
trend.

&&

.AVIATION...Updated at 2320Z.

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
favor the typical diurnal tendencies with west to southwest winds
continuing through the evening hours before shifting out of the
east overnight. Some late afternoon/early evening gusts to near 20
kts will continue before gusts subside by the late evening hours.

Southeast California/Southwest Arizona including KIPL and KBLH:
Gusty winds, especially at KIPL, will continue to be the main
weather issue under clear skies throughout the TAF period. A
westerly wind component will prevail at KIPL while winds will
fluctuate between the south to southwest at KBLH. Gusts upwards of
20-25 kts will continue at KBLH into the early evening hours
before subsiding while periodic gusts near 30 kts is likely at
KIPL this evening before gradually subsiding during the overnight
hours.

&&

.FIRE WEATHER...
A pronounced drying trend will continue into the weekend, resulting
in a complete elimination of rain chances across the entire region.
Temperatures will fall to within a degree or two of normal today and
seasonal temperatures will carry into this weekend. Minimum humidity
levels will drop into the single digits by Saturday and remain there
at least through next Monday. Correspondingly, overnight recovery
will fall into a poor to fair 20-40% range. Upslope afternoon gusts
up to around 20-25 mph will be common over the next several days
resulting in periods of elevated fire danger. By the middle of next
week, temperatures will warm markedly with minimum humidity levels
hovering around 10-15% and continued gusty winds yielding dangerous
conditions for any ongoing wildfires.

&&

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

$$

SHORT TERM...Salerno
LONG TERM...Kuhlman
AVIATION...Lojero
FIRE WEATHER...Kuhlman/Salerno