037  
FXUS66 KSGX 041031  
AFDSGX  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE SAN DIEGO CA  
331 AM PDT FRI JUL 4 2025  
   
SYNOPSIS  
 
MINOR WARMING THROUGH THE HOLIDAY WEEKEND WITH HIGHS NEAR NORMAL  
AND NIGHT AND MORNING LOW CLOUDS CONTINUING ALONG THE COASTAL  
AREAS AND WESTERN VALLEYS. A RIDGE OF HIGH PRESSURE WILL  
STRENGTHEN OVER THE REGION, LEADING TO BUILDING CONFIDENCE IN A  
HEAT WAVE ACROSS THE AREA AND THE POTENTIAL FIRST PUSH OF MONSOON  
MOISTURE BY THE MIDDLE OF NEXT WEEK.  
 
 
   
DISCUSSION...FOR EXTREME SOUTHWESTERN CALIFORNIA INCLUDING ORANGE  
 
SAN DIEGO...WESTERN RIVERSIDE AND SOUTHWESTERN SAN BERNARDINO  
COUNTIES...  
 
TODAY THROUGH THIS WEEKEND...  
 
THE TROUGHING OVER THE EASTERN PACIFIC WATERS IS GOING TO REMAIN  
NEARLY IN PLACE THROUGHOUT THIS PERIOD IN THE FORECAST, WHICH LITTLE  
CHANGE WITH RESPECT TO TEMPERATURES, WITH ONLY A VERY GRADUAL WARMUP  
EACH DAY. IN TERMS OF THE MARINE LAYER, COVERAGE IS GOING TO BE  
SIMILAR TONIGHT, WITH SOME OF THESE LOW CLOUDS MAKING IT INTO THE  
INLAND EMPIRE (IE) AGAIN. AN UPPER LEVEL LOW WILL FORM OFF THE COAST  
OF NORTHERN CALIFORNIA BY LATER IN THE DAY ON SUNDAY AND THEN  
SLOWLY TRANSITION SOUTHWARD. MEANWHILE, THE RIDGE OVER THE DESERT  
SOUTHWEST IS GOING TO CONTINUE TO STRENGTHEN, WHICH WILL RESULT  
IN THE LOWER DESERTS GETTING BACK TO BEING ABOVE 110F BY SUNDAY.  
CONDITIONS WILL REMAIN DRY, ALTHOUGH GIVEN THE POSITION OF THE  
LOW, SOME OF THE LOW CLOUDS THICKENING UP DURING THE OVERNIGHT  
HOURS AND PRODUCING SOME POSSIBLE VERY LIGHT DRIZZLE FOR LOCATIONS  
WEST OF THE MOUNTAINS CANNOT BE RULED OUT COMPLETELY.  
 
MONDAY THROUGH THURSDAY...  
 
BY NEXT WEEK, THE U/L LOW POSITIONED OUT OVER THE COASTAL WATERS  
WILL BEGIN TO PROPAGATE BACK UP TOWARDS THE NORTH AND EVENTUALLY  
BECOME ABSORBED BACK INTO THE LONGWAVE TROUGH UPSTREAM.  
MEANWHILE, THE RIDGE TO THE EAST IS GOING TO FURTHER STRENGTHEN  
AND SLIGHTLY RETROGRADE BACK TOWARDS THE WEST A LITTLE. AS THE  
RIDGE AXIS GETS CLOSER TO THE CWA, TEMPERATURES ARE ALSO GOING TO  
CONTINUE TO RISE, ESPECIALLY FOR THE INLAND AREAS. BY THE MIDDLE  
OF NEXT WEEK (WEDNESDAY), TEMPERATURES WILL LIKELY TOP 100F FOR  
MOST LOCATIONS WITHIN THE IE, AND EVEN APPROACHING 80F FOR MOST OF  
THE COASTAL AREAS. SOME INCREASED MOISTURE COULD HELP TO SLIGHTLY  
MODIFY TEMPERATURES ON THE COOLER SIDE. CONDITIONS WILL CONTINUE  
TO REMAIN DRY THROUGH THE END OF NEXT WEEK.  
 
 
   
AVIATION  
 
041000Z....COAST/VALLEYS...LOW CLOUDS BASED 1200-1700 FT MSL HAVE  
FILLED INTO SD/ORANGE COUNTIES ABOUT 15-20 MILES INLAND. WESTERN AND  
SOUTHERN IE MAY FILL IN AFTER 12Z WITH 60% CHANCE OF BKN CIGS  
BRIEFLY AT KONT. LOCALIZED VIS REDUCTIONS DOWN TO 3-5SM FOR ELEVATED  
VALLEY TERRAIN (I.E. KRNM). CLOUDS TO CLEAR TO THE BEACHES BY 16-17Z  
FRI, WITH CLEARING LIKELY AT THE BEACHES IN THE AFTERNOON. LOW  
CLOUDS WITH SLIGHTLY LOWER BASES 900-1300 FT MSL REFORM AND PUSH  
BACK ASHORE AFTER 03Z SAT. LESS INLAND EXTENT WITH CLOUDS ONLY  
REACHING 10-15 MILES INLAND BY 12Z SAT.  
 
VIS RESTRICTIONS (2-5SM) WILL BE POSSIBLE IN FU ASSOCIATED WITH  
FIREWORKS THIS EVENING, ESPECIALLY IN ORANGE COUNTY AND WESTERN IE.  
 
MOUNTAINS/DESERTS...MOSTLY CLEAR WITH UNRESTRICTED VIS THROUGH  
FRIDAY NIGHT.  
 
 
   
MARINE  
 
NO HAZARDOUS MARINE WEATHER CONDITIONS ARE EXPECTED THROUGH TUESDAY.  
 
 
   
BEACHES  
 
BUILDING SOUTHERLY SWELL (190 DEGREES) OF 3 FEET AT 15-17 SECONDS  
WILL GENERATE ELEVATED SURF OF 3-6 FT WITH SETS TO 7 FT ALONG  
SOUTHERLY FACING BEACHES THROUGH SATURDAY. IN ADDITION, STRONG RIP  
AND LONGSHORE CURRENTS EXPECTED AT ALL BEACHES FRIDAY AND SATURDAY.  
A BEACH HAZARDS STATEMENT IS IN EFFECT AND CONTAINS MORE  
INFORMATION. SWELL AND SURF WILL BEGIN TO LOWER ON 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 THROUGH SATURDAY EVENING FOR ORANGE  
COUNTY COASTAL AREAS-SAN DIEGO COUNTY COASTAL AREAS.  
 
PZ...NONE.  
 
 
 
 
 
PUBLIC...STEWEY  
AVIATION/MARINE...KW  
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