FGUS76 KSGX 190941 ESFSGX Hydrologic Forecast for Extreme Southwestern California National Weather Service San Diego CA 241 AM PDT Tue Aug 19 2025 ...Flash Flood Potential Index for Extreme Southwestern California... .SYNOPSIS... Dry weather will continue through Wednesday. Monsoonal moisture will increase for Thursday into the weekend with increasing chances for afternoon and early evening thunderstorms for the mountains and deserts and increasing flash flood potential for the weekend. $$ CAZ055-056-058-200115- San Bernardino County Mountains-Riverside County Mountains- San Diego County Mountains- Including the cities of Crestline, Lake Arrowhead, Big Bear City, Big Bear Lake, Running Springs, Wrightwood, Idyllwild-Pine Cove, Julian, and Pine Valley 241 AM PDT Tue Aug 19 2025 .TODAY...None...no flash flooding is expected. .WEDNESDAY...None...no flash flooding is expected. $$ CAZ060>062-065-200115- Apple and Lucerne Valleys-Coachella Valley- San Diego County Deserts-San Gorgonio Pass near Banning- Including the cities of Victorville, Hesperia, Apple Valley, Lucerne Valley, Indio, Palm Springs, Cathedral City, Palm Desert, Palm Desert Country, La Quinta, Coachella, and Borrego Springs 241 AM PDT Tue Aug 19 2025 .TODAY...None...no flash flooding is expected. .WEDNESDAY...None...no flash flooding is expected. $$ CAZ048-050-200115- San Bernardino and Riverside County Valleys-The Inland Empire- San Diego County Valleys- Including the cities of Riverside, San Bernardino, Ontario, Moreno Valley, Fontana, Rancho Cucamonga, Corona, Escondido, El Cajon, San Marcos, La Mesa, Santee, and Poway 241 AM PDT Tue Aug 19 2025 .TODAY...None...no flash flooding is expected. .WEDNESDAY...None...no flash flooding is expected. $$ CAZ043-057-552-554-200115- 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 241 AM PDT Tue Aug 19 2025 .TODAY...None...no flash flooding is expected. .WEDNESDAY...None...no flash flooding is expected. $$ 17