The subtropical high pressure was situated near the Four Corners Region with south to southeasterly flow in place across much of southern CA. 5.
Every event with a place to put it; 1 filed by county or forecast zone are drawn at its center, in a lighter ring. Tap one for its entry below.
Deaths and injuries are direct and indirect together, as the offices filed them. Damage is property and crops in the dollars of the year, not adjusted for inflation, and only where an office estimated it.
The episode as NWS PSR wrote it up.
The subtropical high pressure was situated near the Four Corners Region with south to southeasterly flow in place across much of southern CA. This southerly flow pulled in abundant moisture with Precipitable Water Values exceeding 1.5. The combination of the moisture and daytime heating resulted in MLCAPE in excess of 1000 J/KG with DCAPE values in excess of 1500 J/KG. Widespread thunderstorms developed during the early afternoon across the San Diego Mountains and the northern Baja chain with an isolated severe thunderstorm erupting over southern portions of the Imperial Valley just southwest of El Centro. This thunderstorm was nearly stationary producing damaging winds and blowing dust.
The local office's own words before the first event, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.
NWS Phoenix, AZ wrote its last area forecast discussion before the first event at Aug 24, 1:47 PM PST, 27 minutes earlier. Its key messages:
Area Forecast Discussion
National Weather Service Phoenix AZ
247 PM MST Sun Aug 24 2025
.KEY MESSAGES...
- Moderate to Major Heat Risk and Extreme Heat Warnings remain in
effect for much of the lower deserts today.
- A few strong storms will be possible today mainly between
Phoenix and Yuma with strong winds and blowing dust the main
threats.
- Widespread showers and storms are expected on Monday and
possibly Tuesday with some storms being strong along with the
potential for localized heavy rainfall and flooding.
- Temperatures cool to below normal starting Tuesday.
&&
.SHORT TERM /TODAY THROUGH MONDAY/...
For the rest of today, moisture looks to remain marginally
supportive of a few strong storms within the CWA, with isolated to
scattered development expected initially over prominent terrain
features between Phoenix and Yuma (better coverage over Western
Pima County, where several strong thunderstorms have already been
observed early this afternoon). RAP analyzed PWATS are generally
between 1.2-1.5" across Southwest AZ, though a layer of midlevel
dry air is still apparent in Yuma GFS bufr soundings for this
afternoon, which would act to inhibit convective potential. With
the subtropical high centered south of the Four Corners,
southeasterly steering flow will exist today of ~20 kts, acting to
push activity from Western Pima County into Southern Maricopa and
Eastern Yuma County, where DCAPE values are in excess of 1500
J/kg. This presents perhaps the best opportunity for strong to
marginally severe wind gusts today if storms survive into the
lower elevations, also presenting a concern for blowing dust.
A few large scale features evident in current midlevel wv imagery
and 500 mb RAP analysis will be key players in determining how
active our weather gets on Monday: an inverted trough in the Gulf
of California near the tip of Southern Sonora, and a larger upper
level trough with attendant jet max along its southern flank
approaching the CA Coast. Overnight, the inverted trough or
remnants of it are depicted by global guidance rotating
anticyclonically about the subtropical high and into the Western
CWA. Moisture will increase as this occurs, with ensemble mean
PWATS reaching 1.5-1.7". Most CAMs show showers with embedded
thunderstorms blossoming early Monday morning over Southwest AZ
with this moisture and elevated instability being imported over
the area. Simultaneously, the upper trough off the CA Coast draws
near, gradually cooling temperatures aloft (steepening lapse
rates). The jet max at its southern flank shows a pronounced
diffluent signature as it moves over the region, further
supporting the uncapped and favorable environment for storms to
form later in the day. One limiting factor for storm formation
will be lingering cloud cover over Southwest AZ into Southeast CA
from the aforementioned morning showers/storms, however, once they
clear the area, destabilization may be rather rapid, and areas
not clouded over stand a good chance of producing strong
thunderstorms. Localized flash flooding remains a concern for
Monday, particularly with thunderstorms that form in the mid to
late afternoon over SE CA and SW AZ; model soundings show midlevel
RHs in excess of 70%, and LCLs well below the freezing level, so
efficient warm rain processes and strong updrafts can produce
heavy rainfall - a few spots potentially seeing between 1-2" of
rain. Farther to the east across south-central and eastern
Arizona, instability and upper level support is likely to be less
supporting weaker storms but still fairly widespread coverage of
rainfall. PoPs on Monday remain quite high at 50-70% over the bulk
of the area.
&&
.LONG TERM /TUESDAY THROUGH FRIDAY/...
Assuming Monday is quite active across the area with most areas
seeing showers and/or thunderstorms, Tuesday is likely to see
decreased chances of thunderstorms. Moisture is still likely to
be quite plentiful through much of Tuesday and colder air aloft
from the Pacific trough should spread eastward across the area.
However, the upper levels are likely to be less supportive with a
jet max nosing into southern California. The current forecast
thinking for Tuesday is the area of best rainfall potential is
likely to shift more over central and northern Arizona with
decreasing chances across California. Rainfall amounts on average
are likely to be on the lighter side, but we can't rule out some
localized areas seeing upwards of an inch or so.
Starting Tuesday night, we should begin to see drier southwesterly
flow set up over our area, eventually pushing out any remaining
moisture by Friday. Forecast PWATs are shown to drop to between
1.2-1.4" by Wednesday afternoon and 1.0-1.2" by Thursday
afternoon. As a result, rain chances will quickly lower starting
Wednesday with PoPs falling to between 20-30% before dropping to
10% or less starting Thursday. This period of dry conditions
should last through at least next weekend.
Temperatures for the coming week will drop quickly early in the
week as moisture and cloud cover increases. By Tuesday, highs are
likely to drop to around 100 degrees across the lower deserts and
stay there again for Wednesday. As conditions dry out later this
week, highs are expected to slowly creep back toward normal
readings while overnight lows stay fairly comfortable in the 70s
for most places.
&&
.AVIATION...Updated at 1750Z.
South Central Arizona including KPHX, KIWA, KSDL, and KDVT:
Winds will follow diurnal tendencies through mid-afternoon with
speeds generally aob 10 kts. Shower and thunderstorm activity is
likely to develop later this afternoon, mainly to the west and
southwest of the Phoenix metro, with a westerly outflow making its
way through the terminals heading into early this evening. There
is a chance of a northerly outflow as well later during the
evening hours from the convective activity that develops to the
north, however, confidence of occurrence is low at this time.
There is a 50% chance of outflow winds exceeding 30 kts. Winds
should then weaken heading into the overnight period with light
and variable conditions expected before a westerly shift resumes
Monday morning. FEW to SCT mid and high clouds with decks aoa 10
kft AGL will be common throughout the period.
Southeast California/Southwest Arizona including KIPL and KBLH:
A S/SE will be prevalent across the area terminals throughout most
of the TAF period, however, VCSH/VCTS will temporarily cause
erratic wind shifts. Best chances for VCTS late this afternoon
will be across KIPL, with activity likely to develop over
southwestern Imperial County, sending a westerly outflow with VCSH
most likely at KBLH. There is about a 50% chance of outflow winds
exceeding 30 kts. Outside of the thunderstorm outflow winds, the
overall wind speeds should remain aob 12 kts. FEW to SCT mid and
high clouds with decks aoa 10 kft AGL will be common throughout
the period.
FEW to SCT mid and high clouds will be common through the TAF
period with lowest bases AOA 10K ft AGL.
&&
.FIRE WEATHER...
Above normal temperatures today will quickly cool Monday into
Tuesday as moisture and rain chances increase. Thunderstorm
chances are likely to be focused more across southwest Arizona
today before expanding into southeast California and south-central
Arizona on Monday with strong gusty winds being a concern.
Wetting rain chances will also increase to between 30-50% areawide
for Monday and Tuesday with localized heavy rainfall possible.
Afternoon MinRHs will continue to improve from around 20% today to
30% by Tuesday. Drying conditions are then expected later this
week with rain chances mostly coming to an end by Thursday.
&&
.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...Extreme Heat Warning until 8 PM MST this evening for AZZ530>555-
559.
CA...Extreme Heat Warning until 8 PM PDT this evening for CAZ560>570.
&&
SHORT TERM...Whittock
LONG TERM...Kuhlman
AVIATION...Lojero
FIRE WEATHER...KuhlmanThe Yuma radar (KYUX), 98 km away, was scanning. The volume nearest the first event began at 22:15 UTC.
13 thunderstorm wind, 1 dust storm. Local standard time, as filed.
Road closure in the area of Kubler Road and Drew Road due to downed power poles. Wind gusts were estimated at 55-60 mph. Timing estimated from radar. No injuries were reported.
Sunbeam Rest Area located on the eastbound side of I-8 west of El Centro was closed due to damage. Wind gusts were estimated at 55-60 mph. Timing estimated from radar. No injuries were reported.
Road closure in the area of Austin Road and West Wahl Road due to downed power poles. Wind gusts were estimated at 55-60 mph. No injuries were reported.
Downed power poles along Graham Road near Drew Road. Wind gusts were estimated at 55-60 mph. Timing estimated from radar. No injuries were reported.
Downed power pole blocked both lanes along Brockman Road near the intersection with Lyons Road. Wind gusts were estimated at 55-60 mph. Timing estimated from radar. No injuries were reported.
Downed power poles along Anza Road near Pulliam Road. Wind gusts were estimated at 55-60 mph. Timing estimated from radar. No injuries were reported.
Downed power lines along West Evan Hewes Highway near Silsbee Road. Winds were estimated at 55-60 mph. Timing estimated from radar. No injuries were reported.
Downed power poles along Schaniel Road near the intersection with Harrigan Road. Wind gusts were estimated at 55-60 mph. Timing estimated from radar. No injuries were reported.
Downed power poles along Harrigan Road near Graham Road. Wind gusts were estimated at 55-60 mph. Timing estimated from radar. No injuries were reported.
State Route 98 between Ferrell Rd and Weed Rd was closed due to downed tree. Wind gusts were estimated at 55-60 mph. Timing estimated from radar. No injuries were reported.
Downed trees and powerlines along State Route 98, approximately 2.6-3.6 miles west of Calexico, requiring the closure of the highway. Wind gusts were estimated at 55-60 mph. No injuries were reported.
Downed power poles along Clark Road near the intersection with Wahl Road. Wind gusts were estimated at 55-60 mph. Timing estimated from radar. No injuries were reported.
Visibility under 1/4 mile just outside the city of Imperial due to dense blowing dust from thunderstorm outflow winds. No accidents or injuries reported.
Downed power poles along Bennett Road near the US Navy Base. Wind gusts were estimated at 55-60 mph. No injuries were reported.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in California in 2025Every state in 2025This day in weather historyWarnings in California, August 2025
NOAA National Centers for Environmental Information, Storm Events Database, compiled from the National Weather Service’s monthly Storm Data. Complete through 2026-06; NCEI adds each month about 75 days after it ends and revises past years a few times a year. Rebuilt 2026-09-24. Each event’s entry at NCEI: 1289392, 1289397, 1289393, 1291722, 1289394, 1291723, 1289395, 1291715, 1291720, 1289398, 1289399, 1291718, 1289396, 1291719.