316  
FXUS66 KSGX 240948  
AFDSGX  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE SAN DIEGO CA  
248 AM PDT WED JUN 24 2026  
   
SYNOPSIS
 
 
A SLIGHT CHANCE OF SHOWERS AND THUNDERSTORMS WILL CONTINUE INTO  
THIS MORNING, MAINLY FOR THE MOUNTAINS AND DESERTS OF SAN  
BERNARDINO COUNTY. A LOW PRESSURE SYSTEM TO THE NORTH WILL BRING  
STRONGER ONSHORE FLOW AND A COOLING TREND FOR THURSDAY THROUGH  
THE WEEKEND WITH SUNDAY HIGH TEMPERATURES NEAR THE COOLEST FOR THE  
DATE FOR A FEW LOCATIONS. SOUTHWEST TO WEST WINDS FOR THE  
MOUNTAINS AND DESERTS DURING THE AFTERNOON AND EVENING WILL  
STRENGTHEN FOR THURSDAY THROUGH SATURDAY, THEN WEAKEN FOR EARLY  
NEXT WEEK. THE MARINE LAYER WILL DEEPEN LATE IN THE WEEK INTO THE  
WEEKEND WITH NIGHT AND MORNING COASTAL LOW CLOUDS EXTENDING WELL  
INLAND AND ONTO THE COASTAL SLOPES OF THE MOUNTAINS FOR EARLY  
SATURDAY. THEN WARMER FOR EARLY NEXT WEEK, BUT WITH HIGH  
TEMPERATURES REMAINING BELOW AVERAGE.  
 

 
   
DISCUSSION...FOR EXTREME SOUTHWESTERN CALIFORNIA INCLUDING ORANGE
 
 
SAN DIEGO...WESTERN RIVERSIDE AND SOUTHWESTERN SAN BERNARDINO  
COUNTIES...  
   
..NEW AVIATION DISCUSSION FOR 12Z TAFS
 
 
   
SHORT TERM (TODAY THROUGH FRIDAY)
 
 
A SLIGHT CHANCE OF SHOWERS AND THUNDERSTORMS WILL CONTINUE INTO  
THIS MORNING, MAINLY FOR THE MOUNTAINS AND DESERTS OF SAN  
BERNARDINO COUNTY, BEFORE SOUTHWEST FLOW ALOFT BRINGS DRYING FOR  
THIS AFTERNOON. A LOW PRESSURE SYSTEM MOVING SOUTHWARD JUST OFF  
THE COAST OF BRITISH COLUMBIA WILL STRENGTHEN THE ONSHORE FLOW  
ACROSS SOUTHERN CALIFORNIA FOR THURSDAY THROUGH THE WEEKEND WITH A  
COOLING TREND.  
 
HIGH TEMPERATURES FOR TODAY WILL BE WITHIN A FEW DEGREES OF  
AVERAGE FOR MOST AREAS AND AROUND 5 DEGREES ABOVE AVERAGE FOR THE  
DESERTS. HIGH TEMPERATURES FOR TODAY WILL RANGE FROM THE LOWER TO  
MID 70S NEAR THE COAST TO THE MID 80S TO MID 90S FOR THE INLAND  
EMPIRE WITH 108 TO 112 FOR THE LOWER DESERTS. WITH THE COOLING ON  
THURSDAY AND FRIDAY, HIGH TEMPERATURES ON FRIDAY WILL WILL BE AS  
MUCH AS 5 TO 10 DEGREES BELOW AVERAGE FOR THE INLAND EMPIRE. HIGH  
TEMPERATURES ON FRIDAY WILL RANGE FROM AROUND 70 NEAR THE COAST TO  
THE 80S FOR THE INLAND EMPIRE WITH 102 TO 108 FOR THE LOWER  
DESERTS.  
 
THE MARINE LAYER WILL BE AROUND 2000 FEET DEEP WITH NIGHT AND  
MORNING COASTAL LOW CLOUDS SPREADING INTO PORTIONS OF THE WESTERN  
VALLEYS LATE EACH NIGHT. AS ONSHORE FLOW STRENGTHENS, SOUTHWEST  
TO WEST WINDS FOR THE MOUNTAINS AND DESERTS DURING THE AFTERNOON  
AND EVENING WILL STRENGTHEN ON THURSDAY AND FRIDAY WITH GUSTS TO  
30 TO 40 MPH AND WITH GUSTS TO 65 MPH IN THE NORTHERN COACHELLA  
VALLEY BELOW THE SAN GORGONIO PASS.  
 

 
   
LONG TERM (SATURDAY THROUGH TUESDAY)
 
 
HIGH TEMPERATURES WILL COOL ANOTHER 5 DEGREES FOR INLAND AREAS ON  
SATURDAY AND A FEW MORE DEGREES FOR MOST AREAS ON SUNDAY. SUNDAY  
HIGH TEMPERATURES WILL BE AS MUCH AS 12 TO 18 DEGREES BELOW  
AVERAGE FOR THE MOUNTAINS AND INLAND EMPIRE WITH HIGH  
TEMPERATURES RANGING FROM AROUND 70 NEAR THE COAST TO THE MID 70S  
TO LOWER 80S FOR THE INLAND EMPIRE WITH THE MID TO UPPER 90S FOR  
THE LOWER DESERTS. HIGH TEMPERATURES FOR A FEW LOCATIONS ON SUNDAY  
COULD BE NEAR THE COOLEST FOR THE DATE.  
 
HIGH TEMPERATURES WILL BEGIN TO WARM NEXT WEEK WITH MONDAY A FEW  
TO AROUND 5 DEGREES WARMER THAN SUNDAY. SLOWER WARMING OF A FEW  
DEGREES PER DAY WILL CONTINUE FOR TUESDAY AND WEDNESDAY. HIGH  
TEMPERATURES ON TUESDAY WILL STILL BE AS MUCH AS 8 TO 12 DEGREES  
BELOW AVERAGE FOR THE MOUNTAINS AND INLAND VALLEYS WITH HIGH  
TEMPERATURES RANGING FROM AROUND 70 NEAR THE COAST TO THE UPPER  
70S TO MID 80S FOR THE INLAND EMPIRE WITH THE UPPER 90S TO 102  
FOR THE LOWER DESERTS.  
 
THE MARINE LAYER WILL DEEPEN TO AROUND 4000 FEET BY EARLY SUNDAY  
WITH NIGHT AND MORNING COASTAL LOW CLOUDS EXTENDING WELL INLAND  
AND ONTO THE COASTAL SLOPES OF THE MOUNTAINS. THE MARINE LAYER  
WILL BEGIN TO DECREASE IN DEPTH EARLY NEXT WEEK WITH COASTAL LOW  
CLOUDS FOR EARLY TUESDAY EXTENDING INLAND INTO PORTIONS OF THE  
INLAND VALLEYS.  
 
ONSHORE FLOW WILL BE STRONGEST ON SATURDAY WITH SOUTHWEST TO WEST  
WINDS FOR THE MOUNTAINS AND DESERTS DURING THE AFTERNOON AND  
EVENING GUSTING TO 35 TO 45 MPH WITH GUSTS TO 75 MPH IN THE  
NORTHERN COACHELLA VALLEY BELOW THE SAN GORGONIO PASS. THE ECMWF  
EXTREME FORECAST INDEX HAS THESE WINDS IN THE 80TH TO 90TH  
PERCENTILE FOR THIS TIME OF THE YEAR, LOCALLY TO THE 95TH  
PERCENTILE. THE WINDS WILL BEGIN TO WEAKEN ON SUNDAY WITH GREATER  
WEAKENING EARLY NEXT WEEK.  
 

 
   
AVIATION
 
 
240930Z...COAST/VALLEYS...LOW CLOUDS WITH BASES 1000-1500FT MSL HAVE  
CREPT INTO COASTAL AREAS UNDER MID/HIGH LEVEL CLOUDS AOA 20000FT  
MSL. DUE TO THESE UPPER LEVEL CLOUDS, LOW LEVEL CLOUD FORMATION WILL  
BE PATCHY AND INTERMITTENT AT TIMES. LOW CLOUDS WILL CLEAR LAND  
AREAS 16-17Z. EXPECT LOW CLOUDS WITH SIMILAR BASES RETURNING AFTER  
03-04Z THURSDAY WITH BETTER COVERAGE.  
 
MOUNTAINS/DESERTS...VFR CONDITIONS EXPECTED THROUGH THE TAF PERIOD  
WITH SCT-BKN HIGH CLOUDS AOA 15000FT MSL. MID TO UPPER LEVEL CLOUDS  
WILL CLEAR THE AREA BY 22-23Z GIVING WAY TO MOSTLY CLEAR SKIES.  
 

 
   
MARINE
 
 
NO HAZARDOUS MARINE CONDITIONS ARE EXPECTED THROUGH MONDAY.  
 

 
   
BEACHES
 
 
SURF WILL CONTINUE TO INCREASE THIS EVENING WITH THE ARRIVAL OF A 3  
FOOT 15 TO 18 SECOND PERIOD SOUTH SWELL FROM 190 TO 210 DEGREES.  
SURF OF 4 TO 6 FT IS EXPECTED THROUGH THURSDAY. EXPECT LOCALLY  
HAZARDOUS SWIMMING CONDITIONS AND STRONG RIP CURRENTS THROUGH THE  
WEEK. SEE THE BEACH HAZARDS STATEMENT FOR MORE DETAILS.  
 

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

 
   
SGX WATCHES/WARNINGS/ADVISORIES
 
 
CA...BEACH HAZARDS STATEMENT THROUGH THURSDAY EVENING FOR ORANGE  
COUNTY COASTAL AREAS-SAN DIEGO COUNTY COASTAL AREAS.  
 
RED FLAG WARNING UNTIL 11 AM PDT THIS MORNING FOR VICTOR VALLEY  
-APPLE VALLEY -LUCERNE VALLEY -JOHNSON VALLEY.  
 
EXTREME HEAT WARNING FROM 11 AM THIS MORNING TO 8 PM PDT  
THURSDAY FOR SAN DIEGO COUNTY DESERTS.  
 
PZ...NONE.  
 

 
 

 
 
PUBLIC...17  
AVIATION/MARINE/BEACHES...VILLAFANE  
 
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