512  
WGUS66 KSGX 211947  
FFASGX  
 
URGENT - IMMEDIATE BROADCAST REQUESTED  
FLOOD WATCH  
NATIONAL WEATHER SERVICE SAN DIEGO CA  
1147 AM PST SUN DEC 21 2025  
 
CAZ048-055>057-060-061-065-552-554-220630-  
/O.NEW.KSGX.FA.A.0006.251224T0000Z-251225T0600Z/  
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/  
SAN BERNARDINO AND RIVERSIDE COUNTY VALLEYS-THE INLAND EMPIRE-SAN  
BERNARDINO COUNTY MOUNTAINS-RIVERSIDE COUNTY MOUNTAINS-SANTA ANA  
MOUNTAINS AND FOOTHILLS-APPLE AND LUCERNE VALLEYS-COACHELLA  
VALLEY-SAN GORGONIO PASS NEAR BANNING-ORANGE COUNTY COASTAL AREAS-  
ORANGE COUNTY INLAND AREAS-  
INCLUDING THE CITIES OF LAGUNA BEACH, CRESTLINE, CATHEDRAL CITY,  
WRIGHTWOOD, ORANGE, BIG BEAR LAKE, LA QUINTA, BIG BEAR CITY,  
APPLE VALLEY, SANTA ANA, LUCERNE VALLEY, INDIO, RIVERSIDE, LAKE  
ARROWHEAD, COACHELLA, ONTARIO, HESPERIA, VICTORVILLE, FONTANA,  
IRVINE, NEWPORT BEACH, PALM SPRINGS, PALM DESERT, PALM DESERT  
COUNTRY, RUNNING SPRINGS, SAN CLEMENTE, SAN BERNARDINO, MISSION  
VIEJO, HUNTINGTON BEACH, MORENO VALLEY, CORONA, ANAHEIM, GARDEN  
GROVE, IDYLLWILD-PINE COVE, COSTA MESA, RANCHO CUCAMONGA, AND  
FULLERTON  
1147 AM PST SUN DEC 21 2025  
   
..FLOOD WATCH IN EFFECT FROM 4 PM TUESDAY THROUGH 10 PM WEDNESDAY
 
 
* WHAT...FLOODING CAUSED BY EXCESSIVE RAINFALL IS POSSIBLE.  
 
* WHERE...A PORTION OF SOUTHWEST CALIFORNIA, INCLUDING THE FOLLOWING  
AREAS, APPLE AND LUCERNE VALLEYS, COACHELLA VALLEY, ORANGE COUNTY  
COASTAL AREAS, ORANGE COUNTY INLAND AREAS, RIVERSIDE COUNTY  
MOUNTAINS, SAN BERNARDINO COUNTY MOUNTAINS, SAN BERNARDINO AND  
RIVERSIDE COUNTY VALLEYS-THE INLAND EMPIRE, SAN GORGONIO PASS NEAR  
BANNING AND SANTA ANA MOUNTAINS AND FOOTHILLS.  
 
* WHEN...FROM TUESDAY AFTERNOON THROUGH WEDNESDAY EVENING.  
 
* IMPACTS...EXCESSIVE RUNOFF MAY RESULT IN FLOODING OF RIVERS,  
CREEKS, STREAMS, AND OTHER LOW-LYING AND FLOOD-PRONE LOCATIONS.  
MUD AND DEBRIS FLOW ARE POSSIBLE NEAR AND IN BURN SCARS, INCLUDING  
THE AIRPORT, BRIDGE AND LINE BURN SCARS.  
 
* ADDITIONAL DETAILS...  
- AN ATMOSPHERIC RIVER IS EXPECTED TO BRING WIDESPREAD MODERATE  
TO HEAVY RAIN TO THE AREA LATE TUESDAY THROUGH WEDNESDAY.  
SHOWERS COULD BEGIN TO DEVELOP AS EARLY AS TUESDAY EVENING,  
ESPECIALLY IN THE MOUNTAINS. HEAVIEST MOST WIDESPREAD RAIN IS  
EXPECTED WEDNESDAY MORNING CONTINUING THROUGH THE AFTERNOON  
IN THE COACHELLA VALLEY AND IN THE MOUNTAINS. PEAK RAINFALL  
RATES OF 0.50 TO 1 INCH PER HOUR ARE EXPECTED. THERE IS A  
POTENTIAL FOR LOCALLY HEAVIER HOURLY RAINFALL RATES TO  
DEVELOP WITH CONVECTION EMBEDDED IN THE MAIN RAIN BAND OR IN  
THUNDERSTORMS AFTER THE MAIN BAND PASSES. SCATTERED LOCALLY  
HEAVY SHOWERS COULD CONTINUE INTO THURSDAY BUT IMPACTS FROM  
ANY ADDITIONAL RAIN ARE EXPECTED TO BE MORE LOCALIZED.  
-SNOW LEVELS ARE EXPECTED TO REMAIN ABOVE 8000 FT DURING  
PERIOD OF HEAVIEST PRECIPITATION BRINGING A HEIGHTENED RISK  
OF MUD SLIDES, DEBRIS FLOW, AND AREAS OF FLASH FLOODING IN  
THE SAN BERNARDINO COUNTY MOUNTAINS.  
- HTTPS://WWW.WEATHER.GOV/SAFETY/FLOOD  
 
PRECAUTIONARY/PREPAREDNESS ACTIONS...  
 
YOU SHOULD MONITOR LATER FORECASTS AND BE ALERT FOR POSSIBLE FLOOD  
WARNINGS. THOSE LIVING IN AREAS PRONE TO FLOODING SHOULD BE PREPARED  
TO TAKE ACTION SHOULD FLOODING DEVELOP.  
 

 
 

 
 
CAZ043-050-058-062-220630-  
/O.NEW.KSGX.FA.A.0006.251224T1200Z-251225T0900Z/  
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/  
SAN DIEGO COUNTY COASTAL AREAS-SAN DIEGO COUNTY VALLEYS-SAN DIEGO  
COUNTY MOUNTAINS-SAN DIEGO COUNTY DESERTS-  
INCLUDING THE CITIES OF CHULA VISTA, POWAY, OCEANSIDE, CARLSBAD,  
SAN DIEGO, SANTEE, JULIAN, SAN MARCOS, PINE VALLEY, ESCONDIDO, LA  
MESA, VISTA, ENCINITAS, EL CAJON, BORREGO SPRINGS, AND NATIONAL  
CITY  
1147 AM PST SUN DEC 21 2025  
   
..FLOOD WATCH IN EFFECT FROM 4 AM WEDNESDAY THROUGH 1 AM THURSDAY
 
 
* WHAT...FLOODING CAUSED BY EXCESSIVE RAINFALL IS POSSIBLE.  
 
* WHERE...A PORTION OF SOUTHWEST CALIFORNIA, INCLUDING THE FOLLOWING  
AREAS, SAN DIEGO COUNTY COASTAL AREAS, SAN DIEGO COUNTY DESERTS,  
SAN DIEGO COUNTY MOUNTAINS AND SAN DIEGO COUNTY VALLEYS.  
 
* WHEN...FROM LATE TUESDAY NIGHT THROUGH LATE WEDNESDAY NIGHT.  
 
* IMPACTS...EXCESSIVE RUNOFF MAY RESULT IN FLOODING OF RIVERS,  
CREEKS, STREAMS, AND OTHER LOW-LYING AND FLOOD-PRONE LOCATIONS.  
 
* ADDITIONAL DETAILS...  
- AN ATMOSPHERIC RIVER IS EXPECTED TO BRING WIDESPREAD MODERATE  
TO HEAVY RAIN TO THE AREA WEDNESDAY. HEAVIEST MOST WIDESPREAD  
RAIN IS EXPECTED LATE WEDNESDAY MORNING CONTINUING THROUGH  
INTO THE EVENING FOR THE MOUNTAINS AND DESERTS. PEAK RAINFALL  
RATES OF 0.50 TO 1 INCH PER HOUR ARE EXPECTED. SCATTERED  
LOCALLY HEAVY SHOWERS COULD CONTINUE INTO THURSDAY BUT  
IMPACTS FROM ANY ADDITIONAL RAIN ARE EXPECTED TO BE MORE  
LOCALIZED.  
- HTTPS://WWW.WEATHER.GOV/SAFETY/FLOOD  
 
PRECAUTIONARY/PREPAREDNESS ACTIONS...  
 
YOU SHOULD MONITOR LATER FORECASTS AND BE ALERT FOR POSSIBLE FLOOD  
WARNINGS. THOSE LIVING IN AREAS PRONE TO FLOODING SHOULD BE PREPARED  
TO TAKE ACTION SHOULD FLOODING DEVELOP.  
 

 
 

 
 
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