451  
FXUS66 KSGX 251206  
AFDSGX  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE SAN DIEGO CA  
406 AM PST WED FEB 25 2026  
   
SYNOPSIS  
 
WEAK ONSHORE FLOW WILL BRING SLIGHT COOLING TO THE COAST TODAY AND  
A POSSIBLE BRIEF RETURN OF LOW CLOUDS AND LOCALLY DENSE FOG NEAR  
THE COAST LATE TONIGHT INTO EARLY THURSDAY. FOR THURSDAY AND  
FRIDAY, HIGH PRESSURE ALOFT AND WEAK OFFSHORE FLOW WILL BRING  
WARMING WITH HIGH TEMPERATURES ON FRIDAY AS MUCH AS 25 TO 30  
DEGREES ABOVE AVERAGE FOR PORTIONS OF THE INLAND VALLEYS AND LOWER  
COASTAL SLOPES OF THE MOUNTAINS. FOR SATURDAY THROUGH MONDAY,  
HIGH PRESSURE ALOFT WILL WEAKEN AND LOWER-LEVEL FLOW WILL BECOME  
ONSHORE AND STRENGTHEN. THIS WILL SPREADING COOLING AND HIGHER  
COASTAL HUMIDITY INLAND WITH HIGH TEMPERATURES FOR NEXT MONDAY  
AROUND 5 DEGREES ABOVE AVERAGE.  
 
 
   
DISCUSSION...FOR EXTREME SOUTHWESTERN CALIFORNIA INCLUDING ORANGE  
 
SAN DIEGO...WESTERN RIVERSIDE AND SOUTHWESTERN SAN BERNARDINO  
COUNTIES...  
   
SHORT TERM (TODAY THROUGH FRIDAY)  
 
SATELLITE IMAGERY SHOWS SOME HIGH CLOUDS SPREADING ACROSS  
SOUTHERN CALIFORNIA EARLY THIS MORNING WITH NO COASTAL LOW CLOUDS  
AS OF 1 AM. WEAK ONSHORE WILL BRING SLIGHT COOLING OF HIGH  
TEMPERATURES TO COASTAL AREAS TODAY AND A POSSIBLE BRIEF RETURN OF  
LOW CLOUDS AND LOCALLY DENSE FOG NEAR THE COAST LATE TONIGHT INTO  
THURSDAY MORNING.  
 
FOR THURSDAY AND FRIDAY, HIGH PRESSURE ALOFT WILL STRENGTHEN AND  
LOWER-LEVEL FLOW WILL GO WEAKLY OFFSHORE. HIGH TEMPERAUTRES FOR  
THE COAST, VALLEYS, AND MOUNTAINS WILL WARM AROUND 5 DEGREES ON  
THURSDAY AND AROUND ANOTHER 5 DEGREES FOR MOST AREAS ON FRIDAY.  
WITH THE WARMING, HIGH TEMPERATURES ON FRIDAY WILL BE AS MUCH AS  
25 TO 30 DEGREES ABOVE AVERAGE FOR PORTIONS OF THE INLAND VALLEYS  
AND COASTAL SLOPES OF THE MOUNTAINS.  
 
HIGH TEMPERATURES ON FRIDAY WILL RANGE FROM THE MID TO UPPER 70S  
NEAR THE COAST TO AROUND 90 FOR THE INLAND VALLEYS WITH THE MID TO  
UPPER 90S FOR THE LOWER DESERTS. THERE COULD BE WIDESPREAD RECORD  
HIGH TEMPERATURES ON FRIDAY, EXCEPT POSSIBLY AT THE COAST. NBM  
PROBABILITIES OF EXCEEDING THE EXISTING HIGH TEMPERATURE RECORDS  
ON FRIDAY EXCEED 90 PERCENT FOR CHINO, ONTARIO, RIVERSIDE, AND  
RAMONA.  
 
 
   
LONG TERM (SATURDAY THROUGH TUESDAY)  
 
HIGH PRESSURE ALOFT WILL WEAKEN AND ONSHORE FLOW WILL RETURN AND  
STRENGTHEN ACROSS SOUTHERN CALIFORNIA FOR THE WEEKEND INTO EARLY  
NEXT WEEK AS A LOW PRESSURE SYSTEM OVER THE EASTERN PACIFIC  
WEAKENS AS IT MOVES TOWARD THE WEST COAST AND INLAND INTO  
CALIFORNIA. NBM DAILY CHANCES FOR MEASURABLE PRECIPITATION ARE  
HIGHEST FOR NEXT MONDAY AND TUESDAY, BUT REMAIN BELOW 10 PERCENT.  
 
 
   
AVIATION  
 
251030Z...VFR CONDITIONS TODAY AND TONIGHT FOR MOST OF THE REGION  
WITH DECREASING HIGH CLOUDS. EXCEPT: ISOLATED FOG VCNTY KSAN THROUGH  
15Z, NOT LIKELY TO IMPACT THE AIRPORT. BETTER CHANCE (20-30%) OF LOW  
CLOUDS AND FOG TO IMPACT COASTAL AIRPORTS WITH BASES 300-500 FEET  
MSL AND VIS 1-5SM AFTER 02Z INTO THURSDAY.  
 
 
   
MARINE  
 
NO HAZARDOUS MARINE CONDITIONS EXPECTED THROUGH SUNDAY.  
 
 
   
SKYWARN  
 
SKYWARN ACTIVATION IS NOT REQUESTED. HOWEVER WEATHER SPOTTERS ARE  
ENCOURAGED TO REPORT SIGNIFICANT WEATHER CONDITIONS.  
 
 
   
SGX WATCHES/WARNINGS/ADVISORIES  
 
CA...NONE.  
PZ...NONE.  
 
 
 
 
 
PUBLIC...17  
AVIATION/MARINE...MM  
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