780
FXUS65 KPSR 160500
AFDPSR

Area Forecast Discussion
National Weather Service Phoenix AZ
1000 PM MST Mon Jun 15 2026

.UPDATE...
Updated Aviation

&&

.KEY MESSAGES...

- Temperatures up to 8 degrees above normal will result in
widespread moderate Heat Risk with isolated pockets of major Heat
Risk through the middle of the week.

- Chances for showers and thunderstorms continue Tuesday with the
best potential focused over foothill and high terrain locations,
though lower desert storms cannot be ruled out.

- An eastern Pacific area of low pressure will help to dry out the
region while also providing cooler temperatures during the latter
half of the week and weekend.

&&

.SHORT TERM /Today through Tuesday/...
Current RAP40 500mb analysis show region today under H5 heights
between 590-592dam with the core of the subtropical high over
Northwestern Mexico/Central Baja Peninsula. An area of low pressure
remains over Central California and extending into the Eastern
Pacific with broad ridging in the Pacific NW coast line. The
interaction between the subtropical high and the lower pressure over
CA are helping keep moisture more or less trapped here in the lower
deserts, with this morning`s 12Z sounding seeing even a slight
increase compared to yesterday morning`s 12Z sounding with a PWAT
value of 1.54", or near 200-225% of normal for early June. Morning
MUCAPE was 672 J/kg with the GFS computed MLCAPE projected to be
between 750-1000 J/kg to some areas near 1500 J/kg. Additionally,
guidance continues to point towards flow aloft increasing across
central and eastern Arizona, this would set up more favorable
conditions to promote and sustain updrafts.

Like the past few days orographic lift will continue to be the main
trigger for storms to begin their ascent, however with the
conditions mentioned earlier, any storms that do develop in the
higher terrain have a better chance of survival and can move further
down into the Valley. Winds aloft this afternoon have already begun
to shift from the west to out of the northwest, due to this outflow
boundaries are likely to push further down where PoPs today range
between 20-30% across the western and southern Maricopa County and
between 10-20% across eastern Maricopa County, northern Pinal County
and into the eastern higher terrain. While most areas today won`t
see much in terms of accumulations, localized areas where storms
crop up may see a few hundredths of an inch. Otherwise outside of
rainfall potential, other impacts will be the chance for lightning
and blowing dust in the usual dust prone areas.

By Tuesday the moisture will begin to slowly dissipate with PWATs
expected to drop to 1.00-1.25", although even those values are 150-
180% of normal. In addition to losing some of the moisture, the
region will begin to be taken over by stronger ridging leading to
more subsidence as the low over California degrades, this will
severely limit potential for any convective activity for tomorrow
afternoon. The higher terrain areas might be able to squeeze an
isolated shower out, however, currently most CAMs show very little
to nothing in terms of activity even in the higher terrain areas.

Temperatures for today and Tuesday aren`t nearly as exciting.
Afternoon highs today`s will be between 105F-111F and then between
107F-113F for Tuesday as ridging builds over the region. Overnight
lows will also remain in the mid 80s providing very little relief.
Continuing this trend of above normal high and low temperatures
keeps widespread Moderate to localized areas of Major HeatRisk in
the lower deserts. With that said remember that proper heat
precautions should be used if plans take you outside for extended
periods during the next couple of days.

&&

.LONG TERM /Wednesday through Sunday/...
The remainder of the week looks generally unexciting, at least for
our area, as dry air filters in from Wednesday onward. There could
be just enough left over moisture to squeeze out some showers over
southeast Arizona or high terrain areas to our north and east, but
the majority of activity should be focused over Tucson and Flagstaff
CWAs. Something a bit peculiar is the presence of PoPs and QPF for
the Phoenix metro on Friday, even though PWATs will be falling
closer toward near and below normal for June. Moisture at those
levels would likely not even be enough to get high terrain storms,
let alone lower desert rainfall. This could be just an artifact of
the ingested WPC rainfall forecast that gets adjusted with time, but
we would be hard pressed to get rainfall on Friday with dry air
rushing in. Who knows, maybe if we can get enough synoptic lift with
an approaching eastern Pacific trough to interact with stubborn
moisture, some rain chances cannot be completely ruled out, but as
of now, I lean more toward the drier solution.

Speaking of that trough, its migration closer to the Desert
Southwest by the latter half of the week will help us "cool" off a
bit as temperatures fall closer to normal, with perhaps some areas
even seeing below normal readings by the weekend. Now, this does not
mean we get a break from the triple digits, but at least daily
forecasted highs fall closer to 99-108. Not a massive amount of
relief, but enough to back regional HeatRisk down to the lower end
of the Moderate category. Heat precautions will still need to remain
in place regardless. Lower moisture with those cooler temps will
also allow for some more comfortable overnight lows in the upper 60s
to near 80 degrees. Something that will have to monitored is the
potential for elevated fire weather conditions as this feature will
increase winds regionwide. Strength of gusts is still uncertain at
this time, but with very dry air expected to be in place, it would
not take much wind to increase fire danger.

&&

.AVIATION...Updated at 0500Z.

South Central Arizona including KPHX, KIWA, KSDL, and KDVT:
Winds will be the main weather issue through Tuesday night under
periods of mid/high cloud decks. Confidence is low regarding timing
of wind shifts overnight with multiple outflow boundaries
complicating the pattern. Eventually, an easterly component should
prevail Tuesday morning, but quickly revert to a west direction by
late morning. A few gusts ~20kt will be possible late in the
afternoon. TS development in higher terrain should be less prevalent
than the past couple days with very low chances of activity
descending into lower deserts, and even outflow boundaries will
likely not impact aerodromes.


Southeast California/Southwest Arizona including KIPL and KBLH:
No major weather issues will exist through Tuesday night under
mostly clear skies. While an isolated afternoon thunderstorm is
possible Tuesday, chances of direct impact to a terminal location is
very remote. However, outflow winds could conceivably cause abrupt
wind shifts during the late afternoon. Outside of this possibility,
winds should oscillate between SE and SW with some modest late
afternoon/evening gustiness.

&&

.FIRE WEATHER...
Elevated moisture levels will result in isolated to scattered
thunderstorms once again this afternoon and evening, mainly for
higher terrain areas, that will be capable of producing gusty and
erratic winds and dry lightning. Outside of any thunderstorm
outflows, winds will be diurnally driven with the typical afternoon
and evening upslope/upvalley breeziness between 15-25 mph. Enhanced
moisture will bring some benefit as MinRHs range between 15-20% for
the majority of the region, with the exception being SE California
where readings will be closer to 10%. For those areas with better
moisture, the overnight period will offer at least some modest
relief as MaxRH readings rise to 30-50% each night. Those drier
spots further west however will only see values increase to around
25%. Moisture scours out during the back half off the week, which
will decrease dry thunderstorm potential, but drop RHs closer to 10-
15% during the afternoons. By mid to late this week winds will begin
to pick up, mostly along the Colorado River Valley, and eastern AZ
higher terrain, where gusts between 25-30 mph may occur. This can
lead to elevated fire weather, especially as moisture begins to
filter out of the region.

&&

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

&&

$$

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

NWS Phoenix (PSR) Office