087
FGUS76 KSGX 312247
ESFSGX

Hydrologic Forecast for Extreme Southwestern California
National Weather Service San Diego CA
347 PM PDT Sun Aug 31 2025

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

.SYNOPSIS...
Dry conditions are expected through today. Some monsoonal moisture
returns on Monday for a slight risk of afternoon showers and possibly
thunderstorms in the mountains and lower deserts. Chances for
thunderstorms and flooding increase on Tuesday.

$$

CAZ043-048-050-057-552-554-011415-
San Diego County Coastal Areas-
San Bernardino and Riverside County Valleys-The Inland Empire-
San Diego County Valleys-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, Riverside, San Bernardino,
Ontario, Moreno Valley, Fontana, Rancho Cucamonga, Corona,
Escondido, El Cajon, San Marcos, La Mesa, Santee, Poway,
Huntington Beach, Costa Mesa, Newport Beach, Laguna Beach,
San Clemente, Santa Ana, Anaheim, Garden Grove, Irvine, Orange,
Fullerton, and Mission Viejo
347 PM PDT Sun Aug 31 2025

.TONIGHT...None...no flash flooding is expected.
.LABOR DAY...None...no flash flooding is expected.
.TUESDAY...Moderate...thunderstorms are expected to develop and
isolated flash flooding is possible.

$$

CAZ058-061-062-011415-
San Diego County Mountains-Coachella Valley-
San Diego County Deserts-
Including the cities of Julian, Pine Valley, Indio, Palm Springs,
Cathedral City, Palm Desert, Palm Desert Country, La Quinta,
Coachella, and Borrego Springs
347 PM PDT Sun Aug 31 2025

.TONIGHT...None...no flash flooding is expected.
.LABOR DAY...None...no flash flooding is expected.
.TUESDAY...Moderate...thunderstorms are expected to develop and
isolated flash flooding is possible.

$$

CAZ055-056-060-065-011415-
San Bernardino County Mountains-Riverside County Mountains-
Apple and Lucerne Valleys-San Gorgonio Pass near Banning-
Including the cities of Crestline, Lake Arrowhead, Big Bear City,
Big Bear Lake, Running Springs, Wrightwood, Idyllwild-Pine Cove,
Victorville, Hesperia, Apple Valley, and Lucerne Valley
347 PM PDT Sun Aug 31 2025

.TONIGHT...None...no flash flooding is expected.
.LABOR DAY...None...no flash flooding is expected.
.TUESDAY...High...thunderstorms with areas of heavy rain are
expected and the threat of flash flooding is significant.

$$