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FGUS76 KSGX 030907
ESFSGX

Hydrologic Forecast for Extreme Southwestern California
National Weather Service San Diego CA
207 AM PDT Wed Sep 3 2025

...Flash Flood Potential Index for Extreme Southwestern California...

.SYNOPSIS...
Monsoonal moisture will remain in place through Thursday with
chances for thunderstorms during the afternoon and early evening
for the mountains, deserts, and inland valleys. Isolated flash
flooding is possible, mainly for the mountains. Peak hourly
rainfall of 0.25 to 0.50 inch is possible for this afternoon
with isolated hourly rainfall on Thursday afternoon to around
one inch.

$$

CAZ055-040300-
San Bernardino County Mountains-
Including the cities of Crestline, Lake Arrowhead, Big Bear City,
Big Bear Lake, Running Springs, and Wrightwood
207 AM PDT Wed Sep 3 2025

.TODAY...Moderate...thunderstorms are expected to develop and
isolated flash flooding is possible.
.THURSDAY...Moderate...thunderstorms are expected to develop and
isolated flash flooding is possible.

$$

CAZ056-040300-
Riverside County Mountains-
Including the city of Idyllwild-Pine Cove
207 AM PDT Wed Sep 3 2025

.TODAY...Low...the risk of flash flooding is minimal.
.THURSDAY...Moderate...thunderstorms are expected to develop and
isolated flash flooding is possible.

$$

CAZ058-040300-
San Diego County Mountains-
Including the cities of Julian and Pine Valley
207 AM PDT Wed Sep 3 2025

.TODAY...Low...the risk of flash flooding is minimal.
.THURSDAY...Moderate...thunderstorms are expected to develop and
isolated flash flooding is possible.

$$

CAZ060-040300-
Apple and Lucerne Valleys-
Including the cities of Victorville, Hesperia, Apple Valley,
and Lucerne Valley
207 AM PDT Wed Sep 3 2025

.TODAY...Low...the risk of flash flooding is minimal.
.THURSDAY...Low...the risk of flash flooding is minimal.

$$

CAZ061-062-065-040300-
Coachella Valley-San Diego County Deserts-
San Gorgonio Pass near Banning-
Including the cities of Indio, Palm Springs, Cathedral City,
Palm Desert, Palm Desert Country, La Quinta, Coachella,
and Borrego Springs
207 AM PDT Wed Sep 3 2025

.TODAY...Low...the risk of flash flooding is minimal.
.THURSDAY...Moderate...thunderstorms are expected to develop and
isolated flash flooding is possible.

$$

CAZ048-050-040300-
San Bernardino and Riverside County Valleys-The Inland Empire-
San Diego County Valleys-
Including the cities of Riverside, San Bernardino, Ontario,
Moreno Valley, Fontana, Rancho Cucamonga, Corona, Escondido,
El Cajon, San Marcos, La Mesa, Santee, and Poway
207 AM PDT Wed Sep 3 2025

.TODAY...Low...the risk of flash flooding is minimal.
.THURSDAY...Low...the risk of flash flooding is minimal.

$$

CAZ043-057-552-554-040300-
San Diego County Coastal Areas-Santa Ana Mountains and Foothills-
Orange County Coastal Areas-Orange County Inland Areas-
Including the cities of Oceanside, Vista, Carlsbad, Encinitas,
Chula Vista, National City, San Diego, Huntington Beach,
Costa Mesa, Newport Beach, Laguna Beach, San Clemente, Santa Ana,
Anaheim, Garden Grove, Irvine, Orange, Fullerton,
and Mission Viejo
207 AM PDT Wed Sep 3 2025

.TODAY...None...no flash flooding is expected.
.THURSDAY...None...no flash flooding is expected.

$$

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