Flash Flood Warning 13, NWS Phoenix, AZ

694 
WGUS75 KPSR 170924
FFSPSR

Flash Flood Statement
National Weather Service Phoenix AZ
224 AM MST Fri Jul 17 2026

AZC013-170934-
/O.EXP.KPSR.FF.W.0013.000000T0000Z-260717T0930Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Maricopa AZ-
224 AM MST Fri Jul 17 2026

...FLASH FLOOD WARNING WILL EXPIRE AT 230 AM MST EARLY THIS MORNING
FOR MARICOPA COUNTY...

The heavy rain has ended. Flooding is no longer expected to pose a
threat. Please continue to heed remaining road closures.

A Flood Watch remains in effect until 500 AM MST for a portion of
south central Arizona.

&&

LAT...LON 3402 11214 3403 11202 3401 11196 3402 11195
      3399 11193 3395 11187 3392 11187 3388 11190
      3385 11196 3385 11200 3384 11200 3384 11204
      3385 11208 3386 11208 3386 11216 3387 11216
      3386 11217 3390 11220 3398 11217 3401 11213

$$

DT

Area Forecast Discussion
National Weather Service Phoenix AZ
1020 PM MST Thu Jul 16 2026

.UPDATE...Updated 06z Aviation Discussion...

&&

.KEY MESSAGES...

- Temperatures will cool across much of Arizona dropping to below
normal levels while southeast California maintains near normal
readings.

- Showers and thunderstorms will become more widespread across
eastern and central Arizona through Friday with the potential for
heavy rainfall and localized flash flooding.

- A decrease in thunderstorm coverage across lower elevations will
arrive this weekend with the better chances favoring Arizona high
terrain locations.

&&

.SHORT TERM /Today through Friday/...
Early afternoon satellite imagery depicts several small MCVs
traversing the region adding ascent to an already favorable
underlying synoptic pattern of strong divergence aloft atop
deepening moisture profiles. In fact, 12-15 g/kg low level mixing
ratios have spread across much of the CWA supporting scattered
showers ahead of many of these vorticity features. On the other
hand, this thicker moisture has negatively affected insolation over
much of the region yielding limited instability with notable
inhibition still present. This evolution has added complexity and
greater uncertainty to the forecast over the next 36-48 hours as
most modeling systems have not fully captured the extent of cloud
cover and ongoing showers. One consequence of this allows for the
cancellation of the Extreme Heat warning over the western CWA as
clouds and rain have negated intense heating and associated heat
impacts.

Despite all the convectively detrimental features across the local
forecast area, there are a few regional features which could
eventually encourage storms over south-central Arizona tonight into
Friday morning. Intense ascent between 2 well defined easterly waves
(one over central Baja and the other over west Texas) feeding on
1500+ J/kg MLCape across northeast Sonora has fostered explosive
convective development with evidence of a congealing MCS already
this afternoon. High resolution modeling capturing this complex
suggests outflow and vorticity advection forcing new development
over southern Arizona by early evening. While outflow will not be as
strong as previous days, the combined effect with synoptic energy
importation may bring activity towards the Phoenix metro late
evening. Concurrently, a shortwave near the four corners captured in
NE flow was tapping an unstable airmass over northern Arizona, and
also heading towards south-central Arizona tonight.

As a result, there is growing evidence that multiple MCVs and plume
of higher theta-e congeal somewhere around Pinal/eastern Maricopa
counties overnight as discussed in an alternative forecast outcome
yesterday. While MLCape/DCape will be substantially lower during the
overnight, MUCape around 500-750 J/kg will still be present albeit
with deteriorating midlevel lapse rates. Nevertheless, as mixing
ratios reach 15 g/kg and total column PWATs exceed 2.00", any amount
of focused ascent should sufficient for scattered showers and
thunderstorms. Very efficient rainfall rates with the potential for
warm rain processes could yield at least 2-3"/hr given the moisture
profiles, and this scenario matches many historical late night/early
morning events that have produced significant flooding around the
Phoenix metro. The current Flood Watch may need local extensions
through Friday morning once area of storms become established
overnight. Otherwise, deep convection should eventually exhaust
elevated instability by Friday afternoon as atmospheric profiles
become moist adiabatic. While a few lingering showers may persist
through the afternoon, there is very little evidence of renewed
convection during the afternoon/evening given the expected expansive
thick cloud cover left over from the morning activity.

&&

.LONG TERM /Saturday through Wednesday/...
Although some uncertainty remains, guidance continues to trend drier
for this weekend, particularly the GEFS. This drier air is expected
to advect in from the south southwest starting Friday morning and
continue through most of Saturday, lowering PWATs to as low as 1.4-
1.5", but the Euro maintains a more optimistic 1.7-1.9". The
easterly wave is also forecast to weaken while it briefly shifts
back toward central Texas. The combination of the expected drying,
very little instability, and weaker upper level support is likely to
limit shower and thunderstorm potential on Saturday. As of now, much
of the lower deserts should stay quiet on Saturday, while scattered
showers and storms are much more likely over the Arizona high
terrain. Temperatures will begin to recover starting Saturday, but
daytime highs are still likely to fall short of 100 degrees in the
Phoenix area.

Starting Sunday into early next week, the subtropical ridge is
likely to become more elongated from the Great Basin to the Lower MS
River Valley. The remnants of the easterly wave or even a newly
developed disturbance may also become more of a player for monsoon
activity by around Monday or Tuesday as moisture remains plenty
adequate for convection. An increase in easterly upper level winds
across Texas may eventually stretch into the Desert Southwest by
late Monday into Tuesday which could help drive monsoon activity
throughout portions of the lower deserts again. NBM PoPs still favor
the Arizona high terrain through the period, but it seems likely the
lower deserts will see another day or two of active weather.

Forecast temperatures for next week show a gradual upward trend,
despite fairly high model spread. Lower desert daytime highs may
again reach 100 degrees in the Phoenix area by Monday and eventually
back to near normal during the latter half of next week. Locations
across southeast California and southwest Arizona are likely to
maintain near normal temperatures throughout next week.

&&

.AVIATION...Updated at 0515Z.

South Central Arizona including KPHX, KIWA, KSDL, and KDVT:
Showers with embedded thunderstorms will continue across the
region through the overnight period, with coverage gradually
tapering off through Friday morning with mainly dry conditions
expected by the afternoon hours. The overall winds will generally
be out of the east throughout most of the TAF period, with no
anticipation of a westerly wind shift occurring Friday afternoon
at this time. SCT-BKN mid to high clouds aoa 10 kft will be
common throughout the TAF period, although some lower cloud bases
as low as 6-7 kft will be possible temporarily in any heavier
shower/thunderstorm activity.

Southeast California/Southwest Arizona including KIPL and KBLH:
No major aviation concerns are expected during the next 24 hours
under passing mid to high cloud decks. Winds will generally remain
out of the southeast at KIPL and out of the south at KBLH with
overall speeds generally aob 12 kts.

&&

.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 with only isolated chances
over the western districts. Localized heavy rainfall is expected
today into early Friday across the eastern districts with some
potential for gusty outflow winds late this afternoon and early
evening. MinRHs will be 35-55% for the eastern districts through
Saturday to 20-35% across the western districts. 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 and be breezy at times across the
western districts.

&&

.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...Flood Watch until 5 AM MST Friday for AZZ534-537>563.

CA...None.
&&

SHORT TERM...18
LONG TERM...Kuhlman
AVIATION...Lojero
FIRE WEATHER...Kuhlman

Special Weather Statement
National Weather Service Phoenix AZ
630 PM MST Thu Jul 16 2026

AZZ547-549-551-553-555-558-170200-
Fountain Hills/East Mesa AZ-Northwest Pinal County AZ-
Southeast Valley/Queen Creek AZ-Apache Junction/Gold Canyon AZ-
Rio Verde/Salt River AZ-Pinal/Superstition Mountains AZ-
630 PM MST Thu Jul 16 2026

...A STRONG THUNDERSTORM WILL IMPACT MARICOPA AND PINAL COUNTIES
THROUGH 700 PM MST...

At 630 PM MST, Doppler radar was tracking a strong thunderstorm over
Apache Junction. This thunderstorm was nearly stationary.

HAZARD...Wind gusts up to 40 mph.

SOURCE...Radar indicated.

IMPACT...Gusty winds could knock down tree limbs and blow around
         unsecured objects.

Locations impacted include...
Mesa, Apache Junction, Gold Canyon, Superstition Mountains, Gold
Camp, Kings Ranch, Lost Dutchman State Park, Goldfield, and Usery
Mountain Park.

This includes the following highways...
US Highway 60 between mile markers 191 and 203.
AZ Route 202 between mile markers 26 and 30.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If outdoors, consider seeking shelter inside a building.

Torrential rainfall is also occurring with this storm and may lead to
localized flooding. Do not drive your vehicle through flooded
roadways.

&&

LAT...LON 3338 11136 3328 11157 3344 11168 3356 11154
TIME...MOT...LOC 0130Z 230DEG 1KT 3342 11154

MAX HAIL SIZE...0.00 IN
MAX WIND GUST...40 MPH

SDB

Preliminary Local Storm Report
National Weather Service Phoenix AZ
719 PM MST Thu Jul 16 2026

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0658 PM     Rain             1 NE Apache Junction    33.42N 111.54W
07/16/2026  M1.00 Inch       Pinal              AZ   Public

            Rainfall measured over 20 minutes.

&&

SB

Preliminary Local Storm Report
National Weather Service Phoenix AZ
744 PM MST Thu Jul 16 2026

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0730 PM     Flash Flood      2 NE Apache Junction    33.43N 111.53W
07/16/2026                   Pinal              AZ   Trained Spotter

            Washes near the area of Tomahawk Road and
            Apache Trail were running full with water
            flowing over the roadway, stranding a
            vehicle.

&&