277  
FXUS66 KSGX 252023  
AFDSGX  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE SAN DIEGO CA  
123 PM PDT THU JUN 25 2026  
   
SYNOPSIS
 
 
WINDY OVER THE MOUNTAINS AND INTO THE DESERTS, WELL BELOW AVERAGE  
TEMPERATURES ACROSS SOUTHERN CALIFORNIA, AND A DEEPER MARINE LAYER  
CAN BE EXPECTED THIS WEEKEND. AREAS OF DRIZZLE ARE POSSIBLE, WITH  
SATURDAY MORNING AS THE MOST LIKELY DAY. CONDITIONS WILL GRADUALLY  
WARM INTO NEXT WEEK.  
 

 
   
DISCUSSION...FOR EXTREME SOUTHWESTERN CALIFORNIA INCLUDING ORANGE
 
 
SAN DIEGO...WESTERN RIVERSIDE AND SOUTHWESTERN SAN BERNARDINO  
COUNTIES...  
 
A UNSEASONABLE TROUGH OF LOW PRESSURE IS EXPECTED TO DIG INTO THE  
GREAT BASIN THIS WEEKEND. THIS WILL INCREASE THE ONSHORE PRESSURE  
GRADIENT, RESULTING IN STRONGER WESTERLY WINDS ON THE DESERT  
MOUNTAIN SLOPES INTO THE DESERTS, WELL BELOW AVERAGE TEMPERATURES,  
AND A DEEPER MARINE LAYER. BY SUNDAY, HIGHS ARE EXPECTED TO BE 7 TO  
9 DEGREES BELOW AVERAGE AT THE COAST AND LOW DESERTS AND 15 TO 20  
DEGREES BELOW AVERAGE IN THE VALLEYS, MOUNTAINS, AND HIGH DESERT.  
THERE IS ALSO A POTENTIAL FOR PATCHY DRIZZLE WEST OF THE MOUNTAINS,  
MOST LIKELY ON SATURDAY MORNING.  
 
WINDS WILL BEGIN TO INCREASE TODAY ON THE DESERT MOUNTAIN SLOPES AND  
IN THE DESERTS AND STRENGTHEN INTO SATURDAY. WIND GUSTS FRIDAY WILL  
BE 35 TO 50 MPH, COMBINED WITH RELATIVE HUMIDITY 7 TO 15 PERCENT IN  
THE DESERTS WILL CREATE PERIODS OF NEAR CRITICAL TO LOCALLY CRITICAL  
FIRE WEATHER CONDITIONS IN THE DESERTS. FOR MORE INFORMATION ON FIRE  
WEATHER CONCERNS, SEE THE FIRE WEATHER SECTION BELOW. WINDS ARE  
EXPECTED TO PEAK IN STRENGTH ON SATURDAY AFTERNOON AND EVENING, WITH  
PEAK GUSTS 50 TO 65 MPH WITH LOCALLY HIGHER GUSTS POSSIBLE BELOW THE  
SAN GORGONIO PASS. WINDS WILL DECREASE SUNDAY INTO NEXT WEEK.  
 
GLOBAL ENSEMBLES ARE INDICATING BROAD SCALE WEAKER TROUGHING MAY  
LINGER INTO THE END OF NEXT WEEK. EVEN WITH THE LINGERING TROUGHING,  
HEIGHTS WILL RISE LEADING TO A GRADUAL WARMING. ABOUT 27 PERCENT OF  
ENSEMBLE GUIDANCE IS INDICATING A RIDGE MAY BEGIN TO BUILD BACK IN  
BY NEXT WEEKEND. BY NEXT THURSDAY, HIGHS WILL BE 3 TO 7 DEGREES  
BELOW AVERAGE. ADDITIONALLY, THE WEAK TROUGHING WILL MAINTAIN A  
DEEPER MARINE LAYER INTO AT LEAST THE MIDDLE OF NEXT WEEK.  
 

 
   
AVIATION
 
 
251730Z...COAST/VALLEYS...PATCHY LOW CLOUDS TO PERSIST ALONG  
BEACHES, BUT COASTAL AIRPORTS WILL BE SCATTERED OUT THROUGH THE  
AFTERNOON. LOW CLOUDS AROUND 2000 FEET MSL WILL PUSH ASHORE AROUND  
01Z AND EVENTUALLY FILL THE COASTAL BASIN AGAIN OVERNIGHT. VIS  
REDUCED INLAND 1-5SM WITH PARTIAL TERRAIN OBSCURATION 2000-3000 FEET  
MSL. SCATTER OUT FRIDAY 16-18Z.  
 
MOUNTAINS/DESERTS...MOSTLY CLEAR AND VFR CONDITIONS EXPECTED THROUGH  
FRIDAY MORNING, EXCEPT FOR COASTAL SLOPES SHROUDED IN FOG BELOW 3500  
FEET MSL 10-15Z FRIDAY. WEST-SOUTHWEST WINDS 25-35 KTS GUSTS TO 45  
KTS THROUGH MOUNTAIN PASSES AND LOCALLY INTO DESERTS AFTER 21Z,  
DECREASING A LITTLE EARLY FRIDAY MORNING. OCCASIONAL MOD  
UP/DOWNDRAFTS IN LEE OF MOUNTAINS.  
 

 
   
MARINE
 
 
NO HAZARDOUS MARINE CONDITIONS ARE EXPECTED THROUGH TUESDAY.  
 

 
   
BEACHES
 
 
A LONG-PERIOD SOUTH SWELL WILL CONTINUE TO BRING SURF OF 3 TO 6 FEET  
TODAY WITH THE HIGHEST SURF ON SOUTH FACING BEACHES. SEE THE BEACH  
HAZARDS STATEMENT FOR DETAILS.  
 

 
   
FIRE WEATHER
 
 
LOWEST DAYTIME HUMIDITY FOR THE DESERTS WILL FALL TO 7 TO 15 PERCENT  
FRIDAY DURING THE AFTERNOON AND EARLY EVENING. THAT LOW HUMIDITY  
COMBINED WITH SOUTHWEST TO WEST WINDS GUSTING 35 TO 50 MPH DURING  
THE AFTERNOON AND EVENING WILL BRING NEAR CRITICAL TO LOCALLY  
CRITICAL FIRE WEATHER CONDITIONS FOR THE DESERTS ONTO THE DESERT  
SLOPES OF THE MOUNTAINS DURING THE AFTERNOON AND EARLY EVENING TODAY  
AND FRIDAY. HUMIDITY WILL IMPROVE TO NEAR 20 PERCENT BY THE TIME THE  
WINDS PEAK IN STRENGTH ON SATURDAY AFTERNOON. PEAK WIND GUSTS OF 50  
TO 65 MPH, LOCALLY HIGHER POSSIBLE BELOW THE SAN GORGONIO PASS,  
EXPECTED SATURDAY. WINDS WILL WEAKEN SUNDAY.  
 

 
   
SKYWARN
 
 
SKYWARN ACTIVATION IS NOT REQUESTED. HOWEVER WEATHER SPOTTERS ARE  
ENCOURAGED TO REPORT SIGNIFICANT WEATHER CONDITIONS.  
 

 
   
SGX WATCHES/WARNINGS/ADVISORIES
 
 
CA...BEACH HAZARDS STATEMENT UNTIL 10 PM PDT THIS EVENING FOR ORANGE  
COUNTY COASTAL AREAS-SAN DIEGO COUNTY COASTAL AREAS.  
 
WIND ADVISORY FROM 11 AM FRIDAY TO 5 AM PDT SUNDAY FOR APPLE AND  
LUCERNE VALLEYS.  
 
EXTREME HEAT WARNING UNTIL 8 PM PDT THIS EVENING FOR SAN DIEGO  
COUNTY DESERTS.  
 
WIND ADVISORY FROM 5 PM FRIDAY TO 11 AM PDT SUNDAY FOR SAN DIEGO  
COUNTY DESERTS.  
 
WIND ADVISORY FROM 11 AM FRIDAY TO 5 PM PDT SUNDAY FOR SAN  
GORGONIO PASS NEAR BANNING.  
 
PZ...NONE.  
 

 
 

 
 
PUBLIC/FIRE WEATHER...CO  
AVIATION/MARINE...MM  
 
CLICK HERE TO GO TO PREVIOUS BULLETINS.

The Nexlab CA Page Main Text Page