El Mirage, Arizona 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

881
FXUS65 KPSR 160016
AFDPSR

Area Forecast Discussion
National Weather Service Phoenix AZ
516 PM MST Wed Jul 15 2026

.UPDATE...Updated Aviation Discussion.

&&

.KEY MESSAGES...

- Hot and muggy conditions will continue today, however
  temperatures will cool into a near to below normal range by the
  end of the week.

- Shower and thunderstorms chances will increase today across
  eastern and central Arizona with gusty winds and locally heavy
  rainfall possible.

- Thunderstorms may become more widespread Thursday and Friday
  with the potential for heavy rainfall and flash flooding.

&&

.SHORT TERM /Today through Friday/...
Expansive ridging aloft covers much of the Conus this afternoon
under a quasi-rex block pattern featuring a distinct easterly
cutoff low over central Texas bounded by high pressure arcing from
the mid- Atlantic to the northern plains, then into the
Southwest. This places the forecast area under deep easterly flow
subject to shortwave energy passing from the aforementioned Texas
cutoff towards the southern periphery of the high pressure ridge
situated over Arizona. This general pattern is typical for
mid/late July, albeit more amplified with stronger anomaly centers
than is typical, resulting in more impressive forcing mechanisms
around the region. Meanwhile, this synoptic pattern has allowed
ample moisture to stream into much of the CWA with boundary layer
mixing ratios in a favorable 10-12 g/kg range while total column
PWATs exceed 1.50" setting the stage for heavy rainfall potential
with any slow moving or training thunderstorms.

With the local environment recovering from convection Sunday and
Monday, the forecast area is situated in a fairly favorable
location for sustained thunderstorms with modest stretching and
divergence at jet level between well defined easterly
waves/cutoffs over Texas and western Mexico and a SW jet over the
Great Basin. Forecast BUFR soundings for this afternoon/evening
suggest MLCape 500-750 J/kg materializing after daytime heating
and coincident with minimal CinH. While the moistening of the
boundary layer has reduced DCape somewhat, values in excess of
1200 J/kg still appear probable indicating robust outflows likely
producing very gusty winds (albeit largely sub-severe), blowing
dust, and sufficient lift capable of initiating new storms. The
minimal inhibition may allow new storms to form along a single
outflow, however colliding outflows will be more beneficial, and
the preponderance of model output indicates these collisions
focused over western Maricopa County this evening. Forward storm
motion and influence from rapidly propagating outflows should
restrict the flash flood threat this evening, though congealing
storms could produce a localized threat.

The synoptic pattern will become even more conducive for robust
thunderstorms Thursday as at least one shortwave shed from the
aforementioned Texas cutoff progresses towards south-central
Arizona during peak heating. With convective debris and outflows
pumping additional moisture into the middle and lower troposphere,
total column PWATs 1.75-2.00" should be common while boundary
layer mixing ratios settle around 12-13 g/kg by Thursday
afternoon. This moisture profile should result in a near equal
MLCape/DCape balance in a "sweet spot" of 1000-1500 J/kg
historically present during big monsoon thunderstorm events.
Convective inhibition should be nearly absent late afternoon/early
evening, and with underlying deep layer ascent, it should only
take weak outflows to initiate additional storms. Intersecting
outflow boundaries are also likely with consolidating storms over
parts of the CWA resulting in heavy rainfall and flash flooding.
Rainfall rates at least 2-3"/hr appear likely given the moisture
profiles, and a Flash Flood Watch has been issued for south-
central Arizona counties. At this point, HREF and global model
output suggests northern Pinal and SW Maricopa counties as the
focus for the heaviest rainfall.

Considerable forecast uncertainty exists Friday contingent upon
the strength and expanse of thunderstorms Thursday night. A large
subset of modeling indicates the atmosphere becoming completely
overturned by storms and outflows Friday morning with forecast
soundings depicting a classic, post-event moist adiabatic profile.
Should this come to fruition (better than a 50% chance),
convective potential the remainder of Friday would become minimal,
at best, given the combined extensive cloud cover and poor lapse
rates resulting in essentially no instability. A slight
alternative outcome is hinted at by recent operational ECMWF and
NAMNest output which suggests a well defined MCV juxtaposed with a
pool of higher theta-e advecting north through the Phoenix metro
Friday morning. While these type model forecasts with morning
storms forced by an MCV and copious deep moisture are common
during the monsoon, they only come to fruition occasionally every
summer, but when this scenario unfolds, very efficient rain rates
and flooding ensues. Regardless, the strongest model evidence
indicates only small pockets of instability remaining Friday
afternoon, and have cut mandated NBM POPs substantially as even
the most aggressive modeling that always forecasts storms has
little convective response Friday afternoon/evening.

&&

.LONG TERM /Saturday through Tuesday/...
Moderate forecast uncertainty is still an issue for this weekend
into next week as day-to-day shower and thunderstorm chances are
likely to persist. Some slight drying over the weekend, as the
easterly wave to our east southeast gradually weakens, is likely
to bring lower rain chances compared to Thursday and Friday, but
that does not mean it will not be active in some areas. As of
right now, guidance is favoring the Arizona high terrain this
weekend with daily PoPs of 50-70%. An easterly steering flow is
also likely to persist which will enable at least some chances
(20-30%) of showers and storms into the lower deserts this
weekend. Lingering ascent also looks possible this weekend from
the easterly wave, although this is more likely to benefit far
southeast Arizona and northern Mexico.

Model uncertainty increases further during the first half of next
week as guidance is shifting where the subtropical high center
may be and whether or not another easterly wave will impact our
region. There seems to at least be some agreement in gradually
shifting the high center southwestward to somewhere over the
Central Rockies or Central Plains Sunday into Monday, but where it
goes thereafter is much more uncertain. The GEFS favors the high
center settling anywhere from the Four Corners area to into
central New Mexico, while the EPS shows it more over New Mexico
into western Texas. The first half of next week is still likely to
be fairly active as far as storm potential, and could even be
very active if the easterly wave becomes a big factor. However,
the latter half of next week may involve a decrease in monsoon
activity if the high center truly moves closer to or into Arizona.

NBM temperature trends show below normal temperatures lasting
through the weekend for much of Arizona and likely persisting but
gradually warming through the first half of next week. Locations
across southeast California and southwest Arizona should see
temperatures right around normal with most days seeing little
monsoon convection.

&&

.AVIATION...Updated at 0015Z.

South Central Arizona including KPHX, KIWA, KSDL, and KDVT:
Gusty outflow winds are expected to be the primary aviation impact
this evening, with low potential (20-30%) for VCTS/TSRA. An
outflow from the north and from the east may move through, with
the easterly outflow expected to be the stronger of the outflows.
Most probable timing for outflows and VCTS/TSRA is between 01-05Z,
with diminishing activity and wind magnitudes after 05Z. Some
high- based showers may move into the Phoenix area early Thursday
morning, but probability is too low to include in the TAF. Odds of
VCTS/TS are higher Thursday evening/night, with potential for
multiple outflow passages and wind shifts, as well as very heavy
rainfall. Confidence in wind directions this evening and tonight
is low to moderate, with an initial N and/or E shift initially. E
winds may then prevail through the night, with some light
variability, but a SW wind may also develop, dependent on rain
activity southwest of the Phoenix area. Cloud bases will mostly
stay at or above 8-10K ft AGL. The dust potential is low.

Southeast California/Southwest Arizona including KIPL and KBLH:
No major aviation concerns are expected during the next 24 hours.
SE winds will be common at KIPL, though a brief switch of the W/SW
this evening can`t be ruled out. S/SW`rly winds will prevail at
KBLH with a brief window of gusts around 20-25 kt overnight and
again Thursday afternoon. Mostly clear skies will give way to
increasing mid-level clouds tonight into Thursday morning.

&&

.FIRE WEATHER...
Active monsoon weather with elevated moisture levels will continue
through the rest of the week. Shower and thunderstorm chances will
increase over the eastern districts today through Thursday with only
isolated chances over the western districts. Heavy rainfall will
also be possible across the eastern districts by Thursday afternoon.
MinRHs will improve from east to west over the next few days,
increasing from 20-35% today to 30-50% by Friday. Outside of
potential thunderstorm outflows, winds for the eastern districts
will tend to be light and somewhat favor diurnal trends.
Winds will predominately favor the south while becoming breezy
starting Thursday across the western districts.

&&

.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...Extreme Heat Warning until 8 PM MST Thursday for AZZ530-532.

     Flood Watch from Thursday afternoon through late Thursday night
     for AZZ534-537>563.

CA...Extreme Heat Warning until 8 PM PDT Thursday for CAZ562-563-
     565>567-569-570.

&&

$$

SHORT TERM...18
LONG TERM...Kuhlman
AVIATION...Benedict/RW
FIRE WEATHER...Kuhlman