735  
FXUS66 KSGX 070002  
AFDSGX  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE SAN DIEGO CA  
502 PM PDT MON APR 6 2026  
   
SYNOPSIS
 
 
WIDESPREAD MID AND HIGH CLOUDS TODAY WILL CLEAR FROM THE WEST  
OVERNIGHT. LOW CLOUDS AND FOG WILL BECOME MORE WIDESPREAD EACH  
NIGHT AND MORNING THROUGH THE WEEK AS THE MARINE LAYER DEEPENS.  
TEMPERATURES WILL FLUCTUATE A FEW DEGREES EACH DAY THROUGH MID-  
WEEK, REMAINING AROUND 5 TO 10 DEGREES ABOVE NORMAL. MUCH COOLER  
WITH GUSTY ONSHORE WINDS AND CHANCES OF PRECIPITATION FOR FRIDAY  
THROUGH THE WEEKEND.  
 

 
   
DISCUSSION...FOR EXTREME SOUTHWESTERN CALIFORNIA INCLUDING ORANGE
 
 
SAN DIEGO...WESTERN RIVERSIDE AND SOUTHWESTERN SAN BERNARDINO  
COUNTIES...  
   
..UPDATED AVIATION DISCUSSION BELOW
 
 
AN UPPER LEVEL DISTURBANCE BROUGHT WIDESPREAD MID AND HIGH CLOUDS  
TO THE REGION TODAY SOME OF WHICH PRODUCED RAIN. MOST OF THE RAIN  
EVAPORATED IN THE DRY SUB-CLOUD LAYER BEFORE REACHING THE GROUND,  
ALTHOUGH A TRACE OF RAIN REACHED THE GROUND IN A FEW PLACES. THE  
DISTURBANCE ALSO WEAKENED THE MARINE LAYER INVERSION AND MIXED OUT  
THE BOUNDARY LAYER SO THERE HAS BEEN NO LOW CLOUDS OR FOG TO  
SPEAK OF TODAY.  
 
THE DISTURBANCE WILL MOVE EAST TONIGHT TAKING THE MID AND HIGH  
CLOUDS WITH IT AND A TRANSIENT RIDGE OF HIGH PRESSURE WILL  
TRAVERSE THE REGION THROUGH WEDNESDAY. THIS WILL ALLOW THE MARINE  
LAYER TO RETURN, WITH LOW CLOUDS AND FOG IN THE COASTAL AREAS AND  
WESTERN VALLEYS EACH NIGHT AND MORNING. THERE WILL BE ONLY MINOR  
DAY-TO-DAY VARIATIONS IN TEMPERATURE, WITH DAYTIME HIGHS REMAINING  
ABOUT 5-10 DEGREES ABOVE NORMAL EACH DAY.  
 
NUMERICAL MODELS ARE IN PRETTY GOOD AGREEMENT THROUGH FRIDAY WITH  
RESPECT TO THE EVOLUTION OF THE SYNOPTIC PATTERN. A VIGOROUS LOW  
PRESSURE SYSTEM, WITH A CLOSED LOW AT 500 MB, WILL LIKELY IMPACT  
THE REGION FROM THURSDAY THROUGH THE WEEKEND. TEMPERATURES WILL  
BEGIN TO LOWER, CLOUDS INCREASE AND ONSHORE FLOW STRENGTHEN ON  
THURSDAY. DAYTIME HIGH TEMPERATURES WILL BE NEAR OR A FEW DEGREES  
ABOVE SEASONAL AVERAGES AND WESTERLY WINDS COULD BE GUSTING TO  
35-40 MPH IN THE MTNS AND ON ADJACENT DESERT SLOPES.  
 
FOR FRIDAY THROUGH THE WEEKEND...MODEL SOLUTIONS BEGIN TO DIVERGE  
AND THERE IS INCREASING UNCERTAINTY IN THE DETAILS OF THE  
FORECAST. IN GENERAL, CLOUDS WILL CONTINUE TO INCREASE THROUGH  
SATURDAY AND TEMPERATURES WILL CONTINUE TO TREND LOWER. SUNDAY  
WILL LIKELY BE THE COOLEST DAY, WITH HIGH TEMPERATURES NEAR OR AS  
MUCH AS 10-15 DEGREES BELOW SEASONAL AVERAGES. THIS LOW PRESSURE  
SYSTEM WILL LIKELY BE VIGOROUS ENOUGH TO BRING CHANCES FOR  
WIDESPREAD MEASURABLE RAINFALL AND SOME MOUNTAIN SNOW. SATURDAY  
WILL BE THE DAY WITH THE BEST CHANCES FOR PRECIP AND THE GREATEST  
ACCUMULATIONS. SNOW LEVELS WILL START OUT ABOVE 7000 FT BEFORE  
LOWERING TO AROUND 6500 FT ON SUNDAY AS THE PRECIPITATION BEGINS  
TO TAPER OFF. THE NATIONAL BLEND OF MODELS CURRENTLY SHOWS A 65%  
CHANCE OF 0.25 OR MORE IN THE MOUNTAINS, A 45%-55% CHANCE IN THE  
VALLEYS AND COASTAL AREAS, ABOUT A 25% CHANCE IN THE HIGH DESERTS  
AND A 10% OR LESS CHANCE IN THE LOWER DESERTS.  
 
THE LOW PRESSURE SYSTEM MOVES EAST BY LATE SUNDAY AND WEAK UPPER  
LEVEL TROUGHING REMAINS OVER THE WESTERN US INTO MONDAY,  
MAINTAINING COOL WEATHER WITH HIGHS NEAR OR A FEW DEGREES BELOW  
SEASONAL AVERAGES.  
 

 
   
AVIATION
 
 
070000Z...SKC ACROSS MOST OF THE REGION CURRENTLY. LACK OF HIGH  
CLOUDS SHOULD CREATE BETTER CONDITIONS FOR LOW CLOUD DEVELOPMENT  
THIS EVENING. LOW CLOUDS BASED 1000-1500 FT MSL DEVELOP FIRST IN SAN  
DIEGO COUNTY COASTAL AREAS AROUND 02-05Z. CLOUDS SLOWLY INCREASE IN  
COVERAGE OVERNIGHT TO INCLUDE ORANGE COUNTY, REACHING 15-20 MILES  
INLAND. AREAS OF MINOR VIS REDUCTIONS FOR ELEVATED COASTAL TERRAIN  
AND WESTERN VALLEYS (3-6SM). SLIGHT CHANCE FOR LOW CLOUDS TO REACH  
THE FAR WESTERN/SOUTHERN INLAND EMPIRE (20% AT KONT). CLOUDS SCATTER  
OUT 15-17Z WITH SKC EXPECTED FOR TUESDAY AFTERNOON AND EARLY EVENING.  
 

 
   
MARINE
 
 
WIND GUSTS IN THE OUTER WATERS COULD EXCEED 20 KNOTS WEDNESDAY  
NIGHT. OTHERWISE, NO HAZARDOUS MARINE CONDITIONS ARE EXPECTED  
THROUGH SATURDAY.  
 

 
   
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...PG  
AVIATION/MARINE...KW  
 
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