914  
FXUS66 KSGX 170453  
AFDSGX  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE SAN DIEGO CA  
953 PM PDT THU APR 16 2026  
   
SYNOPSIS
 
 
A LITTLE COOLER TODAY THAN YESTERDAY UNDER CLOUDY SKIES, WITH  
SOUTHWEST TO WEST WINDS GUSTING 35 TO 45 MPH IN THE MOUNTAINS AND  
DESERTS DURING THE AFTERNOON AND EVENING. THE FLOW WILL TURN  
OFFSHORE ON FRIDAY, WITH WARMING FOR THE COAST AND VALLEYS AND  
CONTINUED COOLING FOR THE DESERTS. THERE WILL BE NORTH TO  
NORTHEAST WINDS ALONG AND BELOW THE COASTAL SLOPES OF THE  
MOUNTAINS, PEAKING FRIDAY MORNING WITH GUSTS TO 35 TO 45 MPH. FOR  
THE WEEKEND, WEAKER WINDS AND WARMER INLAND WITH SUNDAY HIGH  
TEMPERATURES 5 TO 10 DEGREES ABOVE AVERAGE. SOME TIME DURING THE  
EARLY TO MIDDLE PART OF NEXT WEEK, A LOW PRESSURE SYSTEM WILL MOVE  
INTO CALIFORNIA BRINGING COOLER AND BREEZY WEATHER WITH A LESS  
THAN 20 PERCENT CHANCE OF MEASURABLE PRECIPITATION.  
 

 
   
DISCUSSION...FOR EXTREME SOUTHWESTERN CALIFORNIA INCLUDING ORANGE
 
 
SAN DIEGO...WESTERN RIVERSIDE AND SOUTHWESTERN SAN BERNARDINO  
COUNTIES...  
 
NEW AVIATION AND MARINE DISCUSSION...  
 
THIS AFTERNOON...A LOW PRESSURE SYSTEM TO OUR SOUTHWEST CONTINUES  
TO BRING WIDESPREAD MID AND HIGH CLOUDS TO SOCAL, ALONG WITH  
ONSHORE FLOW AND SLIGHTLY LOWER TEMPERATURES. THE MARINE LAYER HAS  
BEEN DISRUPTED BY THIS SYSTEM AND THERE IS NO SIGNIFICANT INVERSION  
AND VERY FEW LOW CLOUDS, MOSTLY OVER THE COASTAL WATERS. AS THIS  
SYSTEM MOVES INLAND OVER NORTHERN BAJA THIS EVENING AND TONIGHT,  
THE ONSHORE FLOW WILL STRENGTHEN BRIEFLY PRODUCING WESTERLY WINDS  
LOCALLY GUSTING 35 TO 45 MPH IN THE MOUNTAINS AND DESERTS.  
 
FOR LATE TONIGHT INTO FRIDAY MORNING...A SURFACE HIGH WILL MOVE  
INTO THE GREAT BASIN, BRIEFLY SETTING UP OFFSHORE FLOW. GUSTY  
NORTH TO NORTHEAST WINDS WILL DEVELOP EARLY FRIDAY MORNING, PEAK  
DURING THE DAY AND WEAKEN FRIDAY EVENING. GUSTS OF 35 TO 45 MPH  
ARE EXPECTED IN AND BELOW THE CAJON PASS, ALONG AND BELOW THE  
COASTAL SLOPES OF THE SANTA ANA MOUNTAINS, AND IN NORTHERN AND  
EASTERN PORTIONS OF THE COACHELLA VALLEY. THE OFFSHORE FLOW WILL  
ALSO BRING ABOUT 5 DEGREES OF WARMING TO THE AREAS WEST OF THE  
MOUNTAINS BUT THE DESERTS COULD BE ABOUT 5 DEGREES COOLER THAN  
TODAY. HIGH TEMPERATURES ON FRIDAY WILL BE MOSTLY IN THE 70S FOR  
THE COAST AND VALLEYS TO AROUND 80 FOR THE WESTERN VALLEYS AND  
INLAND COASTAL AREAS WITH HIGH TEMPERATURES FOR THE LOWER DESERTS  
IN THE LOWER TO MID 80S.  
 
THE OFFSHORE WINDS WILL WEAKEN ON SATURDAY AND A TRANSIENT RIDGE  
OF HIGH PRESSURE AHEAD OF A LOW PRESSURE SYSTEM, DEVELOPING SOUTH  
OF THE GULF OF ALASKA, WILL BRING DAYTIME TEMPERATURES ABOUT 5-10  
DEGREES HIGHER THAN FRIDAY. HIGH TEMPERATURES ARE EXPECTED TO  
RANGE FROM THE LOWER 70S NEAR THE COAST TO THE LOWER TO MID 80S  
FOR THE INLAND EMPIRE WITH THE LOWER DESERTS AROUND 90.  
 
WARMING WILL CONTINUE FOR INLAND AREAS ON SUNDAY UNDER SOUTHWEST  
FLOW ALOFT AHEAD OF THE LOW PRESSURE SYSTEM MOVING SOUTHWARD OFF  
THE CA COAST. HIGH TEMPERATURES ON SUNDAY WILL LIKELY BE 5 TO 10  
DEGREES ABOVE AVERAGE FOR MOST AREAS. SUNDAY HIGH TEMPERATURES  
WILL RANGE FROM THE LOWER 70S NEAR THE COAST TO THE LOWER TO MID  
80S FOR THE INLAND EMPIRE WITH THE LOWER TO MID 90S FOR THE LOWER  
DESERTS.  
 
FOR MONDAY THROUGH THE MIDDLE OF NEXT WEEK...MODEL SOLUTIONS HAVE  
NOT YET BEGUN TO CONVERGE ON A SOLUTION SO FORECAST DETAILS ARE  
QUITE UNCERTAIN. THE LOW PRESSURE SYSTEM WILL MOVE INLAND OVER CA  
BY WED OR THU. WE CAN SAY WITH REASONABLE CONFIDENCE THAT CONDITIONS  
WILL BE COOLER AND BREEZIER WITH INCREASING CLOUDS. ALMOST HALF  
THE ENSEMBLE MEMBERS ACROSS MODEL PLATFORMS INDICATE THE POTENTIAL  
FOR MEASURABLE PRECIPITATION BUT TIMING AND AMOUNTS ARE UNCERTAIN.  
AT THIS TIME, THE NATIONAL BLEND OF MODELS INDICATE A 15%-25%  
CHANCE OF MEASURABLE PRECIP BETWEEN NEXT TUE AND THU.  
 

 
   
AVIATION
 
 
170430Z...COAST/VALLEYS/COASTAL SLOPES...PATCHY LOW CLOUDS BASED  
1500-2000 FT MSL ARE CURRENTLY DEVELOPING OVER COASTAL AREAS. LOW  
CLOUDS SPREAD INTO SAN DIEGO/ORANGE COUNTY VALLEYS AND THE SOUTHERN  
INLAND EMPIRE BY 06-09Z, THOUGH COVERAGE SHOULD REMAIN PATCHY AND  
INTERMITTENT FOR ALL AREAS. GREATEST CHANCE FOR BKN CIGS WILL OCCUR  
NOW THROUGH 09Z IN SAN DIEGO COUNTY. THEREAFTER, FLOW TURNS OFFSHORE  
WITH ANY REMAINING LOW CLOUDS CLEARING OUT OF LAND AREAS BY 12-15Z.  
NORTH TO NORTHEAST WINDS BECOME ELEVATED TO STRONG STARTING 09-12Z  
ALONG COASTAL SLOPES IN SAN BERNARDINO COUNTY. THEN, WINDS SPREAD  
THROUGH/DOWNWIND OF THE CAJON PASS INTO THE INLAND EMPIRE AND SANTA  
ANA MTNS. GUSTS 35-45 MPH EXPECTED, LOCALLY TO 50 MPH THROUGH WIND  
PRONE PASSES AND COASTAL SLOPES. MOD UP/DOWNDRAFTS IN LEE OF  
MOUNTAINS. WINDS WEAKEN AND EVENTUALLY DIMINISH FRIDAY AFTERNOON.  
 
DESERT SLOPES/DESERTS...ELEVATED TO STRONG WESTERLY WINDS ARE  
CURRENTLY GUSTING UP TO 30 TO 40 KNOTS IN THE HIGH DESERT, ALONG  
DESERT SLOPES AND THROUGH MOUNTAIN PASSES. WINDS WILL SHIFT TO  
NORTHERLY AND WEAKEN FROM 06-12Z. THE EXCEPTION WILL BE THE NORTHERN  
COACHELLA VALLEY WHERE NORTHERLY WINDS WILL REMAIN STRONG INTO EARLY  
FRIDAY AFTERNOON. MOD UP/DOWNDRAFTS IN LEE OF MOUNTAINS.  
 

 
   
MARINE
 
 
NO HAZARDOUS MARINE CONDITIONS ARE EXPECTED THROUGH MONDAY.  
 

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

 
   
SGX WATCHES/WARNINGS/ADVISORIES
 
 
CA...WIND ADVISORY FROM 5 AM TO 5 PM PDT FRIDAY FOR ORANGE COUNTY  
INLAND AREAS-SAN BERNARDINO COUNTY MOUNTAINS-SAN BERNARDINO  
AND RIVERSIDE COUNTY VALLEYS-THE INLAND EMPIRE-SANTA ANA  
MOUNTAINS AND FOOTHILLS.  
 
WIND ADVISORY UNTIL 2 AM PDT FRIDAY FOR APPLE AND LUCERNE  
VALLEYS.  
 
PZ...NONE.  
 

 
 

 
 
PUBLIC...PG  
AVIATION/MARINE...KW  
 
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