409  
FXUS66 KSGX 251818  
AFDSGX  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE SAN DIEGO CA  
1018 AM PST THU DEC 25 2025  
   
SYNOPSIS
 
 
STRONG SOUTH WINDS WITH GUSTS TO 55 TO 65 MPH WILL CONTINUE ALONG  
AND BELOW THE DESERT SLOPES OF THE SAN BERNARDINO COUNTY MOUNTAINS  
WILL CONTINUE THROUGH MID AFTERNOON BEFORE DIMINISHING. SCATTERED  
SHOWERS WILL CONTINUE AT TIMES THROUGH THIS EVENING, MAINLY  
ACROSS PORTIONS OF ORANGE AND SOUTHWESTERN SAN BERNARDINO  
COUNTIES. MORE WIDESPREAD SHOWERS WILL SPREAD EASTWARD AND SOUTHWARD  
AND ACROSS THE AREA FOR LATE TONIGHT THROUGH FRIDAY AFTERNOON  
WITH PRECIPITATION AMOUNTS GREATER TO THE NORTH AND LESS TO THE  
SOUTH. SHOWERS WILL DECREASE FOR FRIDAY NIGHT AND EARLY SATURDAY  
FOLLOWED BY DRIER WEATHER THROUGH SUNDAY AND MONDAY. SHOWERS COULD  
RETURN FROM THE SOUTH SOME TIME THE LATTER HALF OF NEXT WEEK  
CENTERED AROUND NEW YEAR'S DAY.  
 

 
   
DISCUSSION...FOR EXTREME SOUTHWESTERN CALIFORNIA INCLUDING ORANGE
 
 
SAN DIEGO...WESTERN RIVERSIDE AND SOUTHWESTERN SAN BERNARDINO  
COUNTIES...  
   
SHORT TERM (TODAY THROUGH SATURDAY)
 
 
WIDELY SCATTERED SHOWERS HAVE CONTINUED OVERNIGHT, MAINLY FOR THE  
ORANGE COUNTY COAST NORTHWARD TO THE SAN BERNARDINO COUNTY  
MOUNTAINS. THE MORE INTENSE CELLS HAVE PRODUCED ISOLATED RAINFALL  
OF ONE-THIRD TO ONE-HALF INCH. SOME OF THESE CELLS HAVE HAD WEAK  
ROTATION AND THERE WERE SOME LIGHTNING STRIKES IN THE WESTERN SAN  
BERNARDINO MOUNTAINS BEFORE MIDNIGHT. THIS GENERAL PATTERN IS  
EXPECTED TO CONTINUE THROUGH THIS EVENING.  
 
MORE WIDESPREAD SHOWERS FROM THE WEST ARE EXPECTED TO SPREAD INTO  
THE AREA BEFORE DAWN ON FRIDAY AND SPREAD EASTWARD AND SOUTHWARD  
ACROSS THE AREA THROUGH FRIDAY AFTERNOON. THERE IS ALSO A SLIGHT  
CHANCE OF THUNDERSTORMS FOR FRIDAY AFTERNOON AND EARLY EVENING.  
SHOWERS WILL DECREASE FOR FRIDAY NIGHT AND EARLY SATURDAY.  
 
FOR FRIDAY FOR PRECIPITATION, EACH ENSEMBLE SYSTEM FORMS ITS OWN  
CLUSTER WITH VERY LITTLE OVERLAP WITH THE ENSEMBLE MEMBERS OF THE  
OTHER MODELS. THE ENSEMBLE SYSTEMS OF THE ECMWF AND CANADIAN MODEL  
ARE RELATIVELY WETTER WITH THE GFS ENSEMBLE SYSTEM RELATIVELY  
DRIER. ALL HAVE THE MORE NORTH, LESS SOUTH DISTRIBUTION OF  
AMOUNTS.  
 

 
   
LONG TERM
 
 
DRYING WITH WEAK OFFSHORE FLOW IS EXPECTED FOR SUNDAY AND MONDAY  
WITH WEAK OFFSHORE. HIGH TEMPERATURES WILL WARM 5 TO 10 DEGREES  
THROUGH MONDAY, BUT REMAIN BELOW AVERAGE. A CUT-OFF LOW PRESSURE  
SYSTEM WILL DEVELOP WELL TO THE SOUTHWEST OF THE AREA EARLY NEXT  
WEEK, THEN MAY BEGIN TO MOVE TOWARD THE NORTHEAST TOWARD THE  
MIDDLE AND LATTER PART OF NEXT WEEK DRAWING SUBTROPICAL MOISTURE  
TOWARDS THE NORTH AND NORTHWEST AHEAD OF IT. THIS COULD BRING A  
RETURN OF SHOWERS AND HIGHER SNOW LEVELS SOME TIME CENTERED AROUND  
NEW YEAR'S DAY. MODEL PRECIPITATION CLUSTERS SHOW THE STRONGEST  
ENSEMBLE SUPPORT IS FOR SOUTHERN CALIFORNIA TO REMAIN DRY FOR NEXT  
WEDNESDAY WITH PRECIPITATION REMAINING TO THE SOUTHWEST OF THE  
AREA.  
 

 
   
AVIATION
 
 
251830Z....COASTS/VALLEYS...LINGERING FEW-BKN CLOUDS WITH BASES 4000-  
6000 FT MSL EXPECTED, ESPECIALLY FOR ORANGE COUNTY INTO THE  
AFTERNOON. LOW LEVEL CLOUDS DEVELOP AGAIN THIS EVENING GENERALLY  
AFTER 02Z FRI, WITH BASES ANYWHERE FROM 1500-3500FT MSL.  
   
MOUNTAINS/DESERTS
 
35-45 KT GUSTS ALONG DESERT SLOPES OF THE  
SAN BERNARDINO COUNTY MTNS AND INTO THE HIGH DESERT THROUGH THIS  
AFTERNOON WITH GUSTS LOCALLY TO 55 KTS THROUGH PASSES. MOD  
UP/DOWNDRAFTS NEAR MTNS AND INTO THE HIGH DESERT. WINDS WEAKEN SOME  
THIS EVENING, BUT GUSTS 25-40 KTS LAST THROUGH THE PERIOD.  
   
REGION-WIDE
 
RAIN MOVES INTO THE REGION FROM THE WEST STARTING  
AROUND 12Z FRI, THOUGH EXACT TIMING IS STILL UNCERTAIN, AND MOVES  
ACROSS THE AREA THROUGH THE DAYTIME. A FEW HOURS OF MVFR CIGS/VIS  
ARE EXPECTED AS THE RAIN MOVES THROUGH.  
 

 
   
MARINE
 
 
SOUTH TO SOUTHWEST WINDS STRENGTHEN SLIGHTLY AGAIN LATE THURSDAY  
INTO FRIDAY, WITH GUSTS INTERMITTENTLY EXCEEDING 20 KTS. WINDS THEN  
TURN NORTHWEST AND GRADUALLY DECREASE LATE FRIDAY INTO SATURDAY.  
 

 
   
MARINE
 
 
SOUTH TO SOUTHWEST WINDS STRENGTHEN SLIGHTLY AGAIN LATE THURSDAY  
INTO FRIDAY, WITH GUSTS INTERMITTENTLY EXCEEDING 20 KTS. WINDS THEN  
TURN NORTHWEST AND GRADUALLY DECREASE LATE FRIDAY INTO SATURDAY.  
 

 
   
HYDROLOGY
 
 
SCATTERED SHOWERS WILL CONTINUE TODAY WITH THE GREATEST COVERAGE  
AND AMOUNTS IN THE SAN BERNARDINO COUNTY MOUNTAINS. SHOWERS WILL  
DECREASE OVER THE SAN BERNARDINO COUNTY MOUNTAINS DURING THIS  
MORNING, THEN BEGIN TO INCREASE FOR THIS AFTERNOON AND EVENING.  
MORE WIDESPREAD SHOWERS WILL SPREAD SOUTHWARD ACROSS THE AREA FROM  
BEFORE DAWN ON FRIDAY THROUGH FRIDAY AFTERNOON WITH SHOWERS  
DECREASING LATE FRIDAY NIGHT INTO SATURDAY MORNING.  
 
THROUGH THIS EVENING FOR ORANGE AND SOUTHWESTERN SAN BERNARDINO  
COUNTIES, ADDITIONAL RAINFALL WITH LIQUID-EQUIVALENT ABOVE THE  
SNOW LEVEL WILL RANGE FROM LESS THAN ONE-TENTH INCH NEAR THE COAST  
TO 0.10 TO 0.25 INCH FOR THE SAN BERNARDINO MOUNTAINS WITH 0.25 TO  
0.50 INCH FOR THE EASTERN SAN GABRIEL MOUNTAINS. RAINFALL RATES  
WILL MOSTLY BE ONE-QUARTER INCH OR LESS PER HOUR WITH ISOLATED  
HOURLY RAINFALL TO AROUND ONE-THIRD INCH.  
 
FOR LATE TONIGHT THROUGH FRIDAY NIGHT FOR ORANGE AND SOUTHWESTERN  
SAN BERNARDINO COUNTIES, ADDITIONAL RAINFALL WITH LIQUID-  
EQUIVALENT ABOVE THE SNOW LEVEL WILL RANGE FROM AROUND 1 INCH NEAR  
THE COAST TO 2 TO 3 INCHES IN THE MOUNTAINS, LOCALLY TO AROUND 4  
INCHES FOR THE EASTERN SAN GABRIEL MOUNTAINS. AMOUNTS WILL  
DECREASE FROM NORTH TO SOUTH AND MORE RAPIDLY ACROSS SAN DIEGO  
COUNTY WITH ONE-QUARTER TO ONE-THIRD INCH ACROSS FAR SOUTHERN SAN  
DIEGO COUNTY.  
 
THE SNOW LEVEL WILL FALL TO AROUND 6500 FEET BY DAWN THIS MORNING,  
RISE TO AROUND 7500 FEET BY FRIDAY MORNING, THEN FALL TO AROUND  
5000 FEET BY SATURDAY MORNING. SNOWFALL OF 2 TO 3 INCHES IS  
POSSIBLE DOWN TO AROUND 7000 FEET WITH 8 TO 14 INCHES POSSIBLE  
ABOVE 8000 FEET.  
 
SHOWERS WILL BECOME MORE SCATTERED IN COVERAGE INTO SATURDAY,  
EVENTUALLY DISSIPATING BY SATURDAY AFTERNOON.  
 

 
   
SGX WATCHES/WARNINGS/ADVISORIES
 
 
CA...HIGH SURF ADVISORY UNTIL 11 AM PST SATURDAY FOR ORANGE COUNTY  
COASTAL AREAS-SAN DIEGO COUNTY COASTAL AREAS.  
 
FLOOD WATCH FROM LATE TONIGHT THROUGH FRIDAY AFTERNOON FOR APPLE  
AND LUCERNE VALLEYS-SAN BERNARDINO COUNTY MOUNTAINS-SAN  
BERNARDINO AND RIVERSIDE COUNTY VALLEYS-THE INLAND EMPIRE.  
 
HIGH WIND WARNING UNTIL 3 PM PST THIS AFTERNOON FOR APPLE AND  
LUCERNE VALLEYS-SAN BERNARDINO COUNTY MOUNTAINS.  
 
PZ...NONE.  
 

 
 

 
 
PUBLIC...MUNYAN  
AVIATION/MARINE/BEACHES...KW  
 
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