883
FXUS65 KPSR 031725
AFDPSR

Area Forecast Discussion
National Weather Service Phoenix AZ
1025 AM MST Wed Jun 3 2026

.UPDATE...18Z Aviation Discussion.

&&

.KEY MESSAGES...

- Slightly above normal temperatures with areas of moderate HeatRisk
will prevail throughout the week before retreating closer to normal
over the weekend.

- Other than a slight chance of a shower or thunderstorm in eastern
Arizona during the next few afternoons, dry conditions under mostly
sunny skies will prevail through the weekend.

- Locally breezy conditions will develop late in the week and this
weekend, particularly across the lower Colorado River Valley and
higher terrain communities.

&&

.SHORT TERM /Today through Friday/...
Current objective analysis reveals a fairly complex pattern over
CONUS with an omega block beginning to break down over the northern
tier of the county, while a weak Pacific low meanders close to the
Baja Peninsula. The latter of these features will continue on
southeastward progression, eventually settling over Chihuahua,
Mexico by the end of the workweek. During this progression, our
regional height field will not change much, hovering around 586-
587dam through Friday, slightly above normal for the start of June.
This will translate to surface temperatures also running a few
degrees (4-6F) above normal with lower desert highs running between
103-109 degrees through Friday. Although not completely abnormal,
these temperatures will still result in widespread moderate
HeatRisk, posing a risk to those sensitive to the heat and others
who may not have ways of sufficiently cooling or hydrating
themselves.

The only noticeable deviation from hot and calm conditions through
the next few days will come in the form of some very isolated
showers and thunderstorms over far eastern Gila County this
afternoon and again Thursday, and some breezy conditions developing
around the Lower Colorado River Valley and higher terrain areas.
toward the end of the week. The slightly increased rainfall potential
is the result of some modest moisture advection working its way
westward from convective activity that spawned over central and
eastern New Mexico. PWAT anomalies may actually push north of 150-
200% as far west as eastern Maricopa and Pinal Counties, but given
that June is climatologically our driest month, it does not take
much moisture to inflate those values. The best moisture will be
focused over the White Mountains, along with other enhanced terrain
features in Graham and Greenlee Counties. However, it is not out of
the question that convection over these area pushes an outflow
toward our area of Gila County and sparks some isolated showers or
thunderstorms, though chances are slim around 10-20%. As for the
winds, models have an eastern Pacific ridge interacting with the
previously mentioned northern Mexico low, subtly enhancing our
regional pressure gradient. By Thursday, gusts 20-25 mph will be
most common for areas mentioned above, increase to 25-30 mph by
Friday. With RH values running around 10% and below, even this
marginal breeziness will result in elevated fire danger.

&&

.LONG TERM /Saturday through Tuesday/...
As we head into the weekend, ensembles point towards another trough
moving over western portions of the CONUS, which will eventually
become more amplified and stretch from British Columbia down the
California coast. However, uncertainty remains regarding the
strength and positions of this potential disturbance. The increasing
temperature spread through the weekend and into the start of next
week between the NBM 25th and 75th percentile reflects this
uncertainty. Nonetheless, even with the cooler air associated with
this potential system, it appears widespread triple digits are here
to stay. Regardless of which ensemble solution comes to fruition,
the continuation of breezy, to perhaps locally windy conditions
appears likely. The main question will be how strong gusts may
become, which will be dependent on how tight the regional pressure
gradient becomes. With little moisture flux, any breeziness will
keep the fire weather risk elevated at least through Sunday.

Forecast confidence does not improve for the start of next week as
model clusters show a wide variety of outcomes, with some showing
continued troughing, while others favor the return of high pressure.
The return of ridging across the western CONUS appear to be most
likely outcome at this time, but how amplified this feature becomes,
its placement, and if we remain under some influence of a lingering
area of low pressure remains uncertain at this time. One thing that
does appear certain though, other than our high terrain rain chances
today and Thursday, dry conditions are likely to prevail over the
next week at least for most of the region.

&&

.AVIATION...Updated at 1725Z.

South Central Arizona including KPHX, KIWA, KSDL, and KDVT; and
Southeast California/Southwest Arizona including KIPL and KBLH:

No significant weather issues will exist through Thursday evening
under passing cirrus decks and a few afternoon CU/CB developing
over the mountains east of Phoenix. Confidence is very good that
trends in wind speeds and timing of directional shifts will be
very similar to the past 24 hours. However, the late
evening/overnight shift back to an easterly direction around the
Phoenix metro may occur a few hours earlier than the past couple
days due to decaying outflow descending into the valley from
storms over mountains.

&&

.FIRE WEATHER...
The threat for a isolated dry thunderstorms over southern Gila
County today and Thursday is the main fire weather hazard over the
next few days. Winds will follow typical diurnal tendencies with
typical afternoon upslope breeziness the next couple of afternoons.
Gusts begin to pick up Friday and into the weekend, mainly across
the Lower Colorado River Valley and high terrain areas of the
eastern districts. With daily MinRHs hovering close to 5-10%, even
marginal breezes will result in periods of elevated fire weather
conditions. Isolated instances of near critical to critical
conditions cannot be ruled out. Overnight recovery will offer very
little in terms of relief as MaxRHs run between only 15-45% for most
areas. Breezy, to locally windy, conditions are likely to continue
into the weekend, potentially lingering into the start of next week,
resulting in a prolonged period of daily occurrences of elevated to
near critical fire weather conditions starting on Friday.

&&

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

$$

SHORT TERM...RW
LONG TERM...RW
AVIATION...95/18
FIRE WEATHER...RW

NWS Phoenix (PSR) Office