557
FGUS76 KSGX 052243
ESFSGX

Hydrologic Forecast for Extreme Southwestern California
National Weather Service San Diego CA
343 PM PDT Fri Sep 5 2025

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

.SYNOPSIS...
Isolated thunderstorms are expected to develop Saturday afternoon
in the San Diego and Riverside county mountains. 90th percentile
of the HREF is showing rain rates of 0.5 inch per hour for
Saturday afternoon. Isolated flooding is possible, mainly for the
mountains in San Diego and Riverside Counties. Monsoonal moisture
will decrease Sunday, bringing the return of dry conditions Sunday
through the end of the upcoming week.

$$

CAZ056-058-061315-
Riverside County Mountains-San Diego County Mountains-
Including the cities of Idyllwild-Pine Cove, Julian,
and Pine Valley
343 PM PDT Fri Sep 5 2025

.TONIGHT...Low...the risk of flash flooding is minimal.
.SATURDAY...Low...the risk of flash flooding is minimal.
.SUNDAY...None...no flash flooding is expected.

$$

CAZ055-061315-
San Bernardino County Mountains-
Including the cities of Crestline, Lake Arrowhead, Big Bear City,
Big Bear Lake, Running Springs, and Wrightwood
343 PM PDT Fri Sep 5 2025

.TONIGHT...Low...the risk of flash flooding is minimal.
.SATURDAY...None...no flash flooding is expected.
.SUNDAY...None...no flash flooding is expected.

$$

CAZ060-061315-
Apple and Lucerne Valleys-
Including the cities of Victorville, Hesperia, Apple Valley,
and Lucerne Valley
343 PM PDT Fri Sep 5 2025

.TONIGHT...None...no flash flooding is expected.
.SATURDAY...None...no flash flooding is expected.
.SUNDAY...None...no flash flooding is expected.

$$

CAZ061-062-065-061315-
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
343 PM PDT Fri Sep 5 2025

.TONIGHT...Low...the risk of flash flooding is minimal.
.SATURDAY...None...no flash flooding is expected.
.SUNDAY...None...no flash flooding is expected.

$$

CAZ048-061315-
San Bernardino and Riverside County Valleys-The Inland Empire-
Including the cities of Riverside, San Bernardino, Ontario,
Moreno Valley, Fontana, Rancho Cucamonga, and Corona
343 PM PDT Fri Sep 5 2025

.TONIGHT...None...no flash flooding is expected.
.SATURDAY...None...no flash flooding is expected.
.SUNDAY...None...no flash flooding is expected.

$$

CAZ050-061315-
San Diego County Valleys-
Including the cities of Escondido, El Cajon, San Marcos, La Mesa,
Santee, and Poway
343 PM PDT Fri Sep 5 2025

.TONIGHT...None...no flash flooding is expected.
.SATURDAY...None...no flash flooding is expected.
.SUNDAY...None...no flash flooding is expected.

$$

CAZ043-057-552-554-061315-
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
343 PM PDT Fri Sep 5 2025

.TONIGHT...None...no flash flooding is expected.
.SATURDAY...None...no flash flooding is expected.
.SUNDAY...None...no flash flooding is expected.

$$

CO