105  
FXUS66 KSGX 180823  
AFDSGX  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE SAN DIEGO CA  
123 AM PDT SAT JUL 18 2026  
   
SYNOPSIS
 
 
HIGH TEMPERATURES REMAINING NEAR TO SLIGHTLY ABOVE SEASONAL  
NORMALS THROUGH EARLY NEXT WEEK, WARMEST WEDNESDAY AND THURSDAY.  
DECREASING PRECIPITATION CHANCES INTO EARLY NEXT WEEK WITH ANY  
LIGHT SHOWERS CONFINED TO THE HIGHER MOUNTAIN PEAKS DURING THE  
AFTERNOONS. THERE IS THE POTENTIAL FOR INCREASING MOISTURE AND  
AFTERNOON SHOWERS AND THUNDERSTORMS TOWARDS THE MIDDLE TO END OF  
NEXT WEEK.  
 

 
   
DISCUSSION...FOR EXTREME SOUTHWESTERN CALIFORNIA INCLUDING ORANGE
 
 
SAN DIEGO...WESTERN RIVERSIDE AND SOUTHWESTERN SAN BERNARDINO  
COUNTIES...  
 
MID-LEVEL CLOUDS CONTINUE TO DRIFT EAST AND NORTH ACROSS THE  
REGION THIS MORNING. THERE ARE SOME WEAK RETURNS ON RADAR, BUT  
GIVEN THE VERY DRY LAYER BELOW 700 MB AND LACK OF ANY GAUGE  
REPORTS, MOST IF NOT ALL OF THIS PRECIPITATION IS LIKELY NOT  
REACHING THE SURFACE SO EXPECT A FEW SPRINKLES AT BEST. OTHERWISE  
PATCHY LOW CLOUDS CONTINUING AT THE COAST AND UP TO 10-15 MI  
INLAND, CLEARING BY MID MORNING. GIVEN THE MID-LEVEL CLOUD COVER  
IN PLACE AND A GENERAL DRYING TREND WITH LESS INSTABILITY,  
CONVECTIVE ACTIVITY THIS AFTERNOON WILL BE EXTREMELY LIMITED. A  
FEW LIGHT SHOWERS MAY DEVELOP OVER THE HIGHER PEAKS OF THE SAN  
BERNARDINO AND RIVERSIDE COUNTY MOUNTAINS, BUT THUNDERSTORM  
CHANCES ARE LESS THAN 10%.  
 
GENERALLY LITTLE CHANGE IN THE UPPER LEVEL PATTERN WITH BROAD  
RIDGING ACROSS THE WESTERN US AND THE UPPER HIGH CENTERED NEAR CO  
AND WY. TROPICAL STORM ELIDA, CURRENTLY AROUND 900 MI WEST OF CABO  
SAN LUCAS, WILL MOVE NORTH OFF THE WEST COAST AND WEAKEN INTO  
TUESDAY. BASED ON THE CURRENT TRACK, NO WEATHER IMPACTS ARE  
EXPECTED IN SOUTHERN CALIFORNIA. IT WILL GENERATE HIGHER SWELL AND  
SURF THOUGH - SEE THE BEACHES SECTION FOR MORE DETAILS.  
 
MINOR DRYING OCCURS THROUGH EARLY NEXT WEEK WITH AN MONSOONAL  
MOISTURE GRADUALLY BECOMING HIGHER BASED, LIMITING THE POTENTIAL  
FOR SHOWERS AND THUNDERSTORMS EACH AFTERNOON. FORECAST MAINTAINS  
AROUND A 15% CHANCE OVER THE SAN BERNARDINO MOUNTAINS THROUGH  
TUESDAY. ASIDE FROM ANY MONSOON ACTIVITY, HIGH TEMPERATURES WILL  
REMAIN NEAR SEASONAL NORMALS THROUGH TUESDAY - MID 70S TO LOW 80S  
FOR THE COASTAL AREAS, LOW 80S TO MID 90S IN THE VALLEYS, MID 70S  
TO AROUND 90 IN THE MOUNTAINS, MID 90S TO AROUND 100 IN THE HIGH  
DESERT, AND 100-108 IN THE LOW DESERT. AREAS OF NIGHT AND MORNING  
LOW CLOUDS AND FOG WILL CONTINUE ALONG THE COAST AND FAR WESTERN  
VALLEYS.  
 
AS WE HEAD INTO THE MIDDLE OF NEXT WEEK, THE UPPER HIGH SINKS  
SOUTH TOWARDS TX AND STRENGTHENS. THERE IS STILL SOME SPREAD IN  
THE ENSEMBLES ON THE POSITION OF THE HIGH AND HOW FAR WEST THE  
RIDGE AXIS WILL EXTEND. THIS WILL DICTATE HOW MUCH WARMING WE SEE  
TOWARDS THE MIDDLE OF NEXT WEEK AS WELL AS HOW MUCH MOISTURE WILL  
BE ABLE TO MAKE IT INTO THE AREA. ENSEMBLE MEAN PRECIPITABLE WATER  
PEAKS SOMETIME AROUND THU-FRI FOR THE BEST CHANCES OF CONVECTION  
OVER THE MOUNTAINS, BUT IF THE RIDGE AXIS EXTENDS TOO FAR WEST IT  
MAY BE TOO STABLE FOR ANY SHOWERS OR THUNDERSTORMS TO DEVELOP.  
OTHERWISE SLIGHTLY WARMER FOR THE MIDDLE TO END OF THE WEEK WITH  
HIGHS A FEW DEGREES ABOVE NORMAL, WARMEST WEDNESDAY AND THURSDAY.  
 

 
   
AVIATION
 
 
180530Z....COAST/VALLEYS...MID-LEVEL CLOUDS 15-20KFT MSL ARE  
CURRENTLY INHIBITING LOW CLOUDS FROM FORMING ALONG THE COAST, WHICH  
WILL LIKELY CONTINUE THROUGH 08-09Z. PATCHY LOW CLOUDS 900-1300 FT  
MSL WILL MOVE INTO COASTAL REGIONS AFTER, BECOMING MORE WIDESPREAD  
AS MID-LEVELS CONTINUE TO CLEAR TOWARDS AROUND 12Z. LOW CLOUDS CLEAR  
15-17Z, THEN REFORM AT SIMILAR BASES AND MOVE INTO COASTAL REGIONS  
AFTER 05Z SUN.  
 
MOUNTAINS/DESERTS...VFR CONDITIONS EXPECTED THROUGH THE PERIOD  
WITH SCT MID-LEVEL CLOUDS AOA 15,000FT MSL GRADUALLY CLEARING  
OVERNIGHT. SCT CU BASED 10-12 KFT MSL WILL DEVELOP OVER THE  
RIVERSIDE AND SAN BERNARDINO MTNS AFTER 18Z AND ISO-SCT SHRA/TSRA,  
MOST LIKELY AFTER 20Z, THROUGH 01Z SUNDAY. ANY STORMS THAT  
DEVELOP MAY PRODUCE LIGHTNING, GUSTY WINDS, AND VIS REDUCTIONS.  
 

 
   
MARINE
 
 
NO HAZARDOUS MARINE CONDITIONS ARE EXPECTED THROUGH WEDNESDAY.  
 

 
   
BEACHES
 
 
HIGH AMPLITUDE SOUTHERLY SWELL (4-5 FT WITH A PERIOD OF 12-13  
SECONDS) WILL BUILD SUNDAY, BRINGING ELEVATED TO HIGH SURF AND  
STRONG RIP AND LONGSHORE CURRENTS FOR SUNDAY THROUGH AT LEAST  
TUESDAY. HIGHEST SURF, UP TO 7-9 FT, WILL BE ALONG SOUTH AND  
SOUTHWEST-FACING BEACHES. FURTHER DETAILS CAN BE FOUND IN THE HIGH  
SURF ADVISORY. SURF FALLS A BIT AFTER TUESDAY AND INTO WEDNESDAY  
BEFORE ANOTHER STRONGER SOUTHERLY SWELL (3-4 FT WITH A PERIOD OF 15  
SECONDS) BRINGS ANOTHER ROUND OF ELEVATED SURF FOR THE END OF THE  
WEEK AND INTO THE EARLY WEEKEND. THE HIGH RISK FOR STRONG RIP  
CURRENTS WILL REMAIN FROM SUNDAY THROUGH NEXT WEEK.  
 

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

 
   
SGX WATCHES/WARNINGS/ADVISORIES
 
 
CA...HIGH SURF ADVISORY FROM 5 PM SUNDAY TO 11 PM PDT TUESDAY FOR  
ORANGE COUNTY COASTAL AREAS-SAN DIEGO COUNTY COASTAL AREAS.  
 
PZ...NONE.  
 

 
 

 
 
PUBLIC...SS  
AVIATION/MARINE/BEACHES...CSP  
 
CLICK HERE TO GO TO PREVIOUS BULLETINS.

The Nexlab CA Page Main Text Page