187  
FXUS66 KLOX 180030  
AFDLOX  
 
AREA FORECAST DISCUSSION...UPDATED  
NATIONAL WEATHER SERVICE LOS ANGELES/OXNARD CA  
530 PM PDT FRI JUL 17 2026  
 
UPDATED AVIATION SECTION  
   
SYNOPSIS
 
17/105 PM.  
 
MINIMAL CHANGES EXPECTED OVER THE NEXT FEW DAYS IN THE WAY OF  
TEMPERATURES. MORNING LOW CLOUDS AND FOG WILL RETURN TO MANY  
COASTAL AREAS EACH DAY THROUGH EARLY NEXT WEEK. A WARMING TREND IS  
EXPECTED BY THE MIDDLE OF NEXT WEEK AS UPPER LEVEL HIGH PRESSURE  
BUILDS INTO THE AREA WHILE ONSHORE GRADIENTS WEAKEN.  
 

 
   
SHORT TERM (TDY-MON)
 
17/1224 PM.  
 
NOT MUCH CHANGE IN THE UPPER LEVEL PATTERN OVER SRN CA THRU SUN  
WITH THE REGION UNDER THE SW PERIPHERY OF A LARGE WESTERN U.S.  
UPPER LEVEL HIGH CENTERED MAINLY BETWEEN WY AND CO. H5 HEIGHTS  
OVER THE FORECAST AREA WILL BE GENERALLY IN THE 589-591 DAM RANGE  
THRU THE PERIOD. THE UPPER LEVEL FLOW WILL START OUT MOSTLY  
SOUTHERLY THRU SAT THEN TURN MORE SE INTO SUN. SOME MONSOONAL  
MOISTURE WILL PUSH BACK INTO SW CA THIS WEEKEND WITH AN INCREASE  
MID LEVEL CLOUDS AT TIMES, AND BY SUN SOME AFTERNOON CU BUILDUPS  
CANNOT BE RULED OUT IN THE MTNS ALONG WITH A NON-ZERO CHANCE  
(5-10%) OF A SHOWER OR THUNDERSTORM FOCUSED IN THE VTU/L.A. COUNTY  
MTNS WITH ABOUT A 5 PERCENT OF A SHOWER JUST ABOUT ANYWHERE  
TONIGHT. EVEN SO, IT LOOKS LIKE THE BULK OF THE MONSOONAL MOISTURE  
WILL REMAIN EAST OF L.A. COUNTY THRU SUN. A RAPIDLY WEAKENING  
TROPICAL CYCLONE WILL PAST WELL TO THE WEST SUNDAY INTO MONDAY AND  
MAY PROVIDE A BUMP IN MOISTURE ACROSS THE REGION INCLUDING THE  
CENTRAL COAST BEING CLOSEST TO THE SYSTEM. THE MOST LIKELY  
SCENARIO IS A BUMP UP IN MID TO HIGH CLOUDS ESPECIALLY FOR  
NORTHERN AREAS, HOWEVER, THERE IS A 5-10 PERCENT CHANCE OF A  
SHOWER OR THUNDERSTORM, ESPECIALLY INTO MONDAY.  
 
PRESSURE GRADIENTS WILL BE ONSHORE AND INCREASE OVER THE NEXT  
COUPLE OF DAYS. THIS WILL SUPPORT NEAR NORMAL TEMPERATURES ALONG  
WITH AN INCREASE IN COASTAL NIGHT AND MORNING LOW CLOUDS AND FOG.  
AFTERNOON HIGHS SHOULD RANGE FROM THE 70S TO LOW 80S FOR THE  
COAST, MID 80S TO MID 90S FOR THE VLYS AND LOWER MTNS, AND 90S TO  
AROUND 100 FOR THE DESERTS.  
   
LONG TERM (TUE-FRI)
 
17/1224 PM.  
 
THE LARGE WESTERN U.S UPPER LEVEL HIGH CENTER IS FORECAST TO  
DRIFT S FROM COLORADO ON MON TO THE AREA AROUND NEW MEXICO AND THE  
NORTHERN TEXAS PANHANDLE BY THU. SOUTHWESTERN CA WILL CONTINUE TO  
BE ON THE WESTERN PERIPHERY OF THIS LARGE UPPER LEVEL HIGH, WITH  
H5 HEIGHTS SLOWLY INCREASING TO 592-594 DAM DURING THE EXTENDED  
PERIOD.  
 
THE FLOW ALOFT WILL MOSTLY BE FROM THE SE WITH MONSOONAL MOISTURE  
EXPECTED TO CONTINUE TO PUSH INTO THE AREA. PRECIPITABLE WATER  
VALUES ARE FORECAST TO BE IN THE 1.25 TO 1.40 INCH RANGE FOR THE  
MOST PART WHICH IS ABOUT 150 TO 160 PERCENT OF NORMAL FOR THIS  
TIME OF YEAR. ALTHOUGH THE DEEPEST MOISTURE AND INSTABILITY IS  
FORECAST TO REMAIN EAST OF L.A. COUNTY DURING THE EXTENDED PERIOD,  
IT DOES LOOK LIKE THE BEST CHANCE OF AFTERNOON CONVECTION WILL  
COME WEDNESDAY AND THURSDAY OVER THE MOUNTAINS. FOR NOW, THERE IS  
ONLY A MINIMAL CHANCE OF SHOWERS LATE THU IN THE FCST FOR THE  
EASTERN L.A. COUNTY MTNS. OTHERWISE, THERE IS A NON-ZERO CHANCE  
(10%) FOR A THUNDERSTORM TO DEVELOP IN THE MTNS ESPECIALLY WED AND  
THU. AS WE DRAW CLOSER TO EARLY NEXT WEEK, WE SHOULD HAVE A  
BETTER IDEA OF THE CHANCE AND EXTENT OF AFTERNOON CONVECTION FOR  
THE MIDDLE OF NEXT WEEK.  
 
OTHERWISE, IT LOOK LIKE VARYING AMOUNTS OF NIGHT AND MORNING  
COASTAL LOW CLOUDS AND FOG WILL PREVAIL DURING THE EXTENDED  
PERIOD, WITH A WARMING TREND THRU THE MIDDLE OF NEXT WEEK.  
MODERATE TO HIGH HEAT RISK MAY EXPAND INTO WEDNESDAY OR THURSDAY  
AS PRESSURE GRADIENTS WEAKEN AND MAYBE TURN LIGHTLY OFFSHORE IN  
THE MORNINGS WITH THE POTENTIAL FOR 500 MB HEIGHTS BUILDING TO  
594-596. THERE IS A MODERATE (50-60 PERCENT CHANCE) THAT AT LEAST  
HEAT ADVISORIES WILL BE NEEDED IN SOME AREAS, INCLUDING POTENTIAL  
NEAR THE COAST.  
 

 
   
AVIATION
 
18/0027Z.  
 
AT 2300Z AT KLAX, THE MARINE LAYER WAS 1200 FT DEEP. THE TOP OF  
THE INVERSION WAS AT 3000 FT WITH A MAX TEMPERATURE OF 24 C.  
 
HIGH CONFIDENCE IN VFR TAFS FOR DESERT AIRFIELDS (KPMD & KWJF).  
 
LOW TO MODERATE CONFIDENCE IN REMAINING TAFS. TIMING OF CIG/VSBY  
RESTRICTIONS MAY BE OFF +/- 2.5 HOURS AND FLIGHT MINIMUMS OFF BY  
ONE CATEGORY.  
 
KLAX...LOW TO MODERATE CONFIDENCE IN TAF. ARRIVAL AND CLEARING  
TIMES OF CIGS NEAR 012 (+/- 300FT) SHOULD BE ACCURATE WITHIN  
+/- 2.5 HOURS OF CURRENT FORECAST. THERE IS A 30% CHC EAST WIND  
COMPONENT REACHES 7-8 KNOTS BETWEEN 18/08Z-16Z.  
 
KBUR...MODERATE CONFIDENCE IN TAF. THERE IS A 30% CHANCE OF  
IFR CIGS FROM 18/12Z-18Z. OTHERWISE, VFR CONDITIONS WITH NO WIND  
ISSUES ARE EXPECTED.  
 

 
   
MARINE
 
17/105 PM.  
 
MARGINAL SMALL CRAFT ADVISORY (SCA) NORTHWEST WINDS (20-25 KT)  
AND SEAS WILL IMPACT THE WATERS BEYOND 20 NM FROM SHORE (EXCEPT  
FOR NEARSHORE ALONG THE CENTRAL COAST) THROUGH TONIGHT. LOCALIZED  
GUSTS TO 25 KT MAY OCCUR IN THE FAR WESTERN PORTION OF THE SANTA  
BARBARA CHANNEL THROUGH THIS EVENING. THEN CONDITIONS ARE  
EXPECTED TO REMAIN BELOW SCA LEVELS THROUGH MONDAY EXCEPT FOR  
FAIRLY LOCALIZED SCA LEVEL NORTHWEST WIND GUSTS ACROSS THE OUTER  
WATERS MORE THAN 20 NM FROM SHORE. NORTHWEST WINDS WILL BEGIN TO  
STRENGTHEN TUESDAY AND SCA CONDITIONS ARE EXPECTED TO OCCUR MUCH OF  
NEXT WEEK.  
 
A SERIES OF MODERATE PERIOD SOUTHERLY SWELL WILL IMPACT THE  
WATERS LATE SUNDAY THROUGH MUCH OF NEXT WEEK WHICH MAY IMPACT  
SOUTH FACING HARBORS, INCLUDING THE PORT SAN LUIS AREA.  
 

 
   
BEACHES
 
17/105 PM.  
 
OVER THE EASTERN PACIFIC, TROPICAL STORM ELIDA IS FORECAST TO  
STRENGTHEN TO HURRICANE STATUS TOMORROW. IT IS THEN EXPECTED TO  
MOVE TO THE NORTH AND WEST WELL OFF THE BAJA COAST. ANOTHER  
TROPICAL DISTURBANCE IS EXPECTED TO STRENGTHEN NEXT WEEK AND  
GENERALLY FOLLOW THE PATH OF ELIDA TO THE NORTHWEST. BOTH SYSTEMS  
WILL PRODUCE MODERATE PERIOD SOUTHERLY SWELLS. HIGH SURF  
ADVISORIES AND BEACH HAZARDS STATEMENTS HAVE BEEN ISSUED ACROSS  
SOUTHWEST CALIFORNIA FROM SUNDAY EVENING THROUGH TUESDAY NIGHT.  
THE SECONDARY SYSTEM ON THE HEELS OF ELIDA AND AN INCOMING LONG  
PERIOD SOUTHERN HEMISPHERE SOUTH SWELL FORECAST TO ARRIVE SOMETIME  
LATE NEXT WEEK WILL LIKELY CONTRIBUTE TO CONTINUED AND  
POTENTIALLY MORE HAZARDOUS BEACH CONDITIONS INTO THE FOLLOWING  
WEEKEND. ADDITIONAL HIGH SURF ADVISORIES AND/OR BEACH HAZARDS  
STATEMENTS ARE LIKELY NEXT WEEK.  
 

 
   
LOX WATCHES/WARNINGS/ADVISORIES
 
 
CA...HIGH SURF ADVISORY IN EFFECT FROM 5 PM SUNDAY TO 11 PM PDT  
TUESDAY FOR ZONES 87-354-362-366. (SEE LAXCFWLOX).  
BEACH HAZARDS STATEMENT IN EFFECT FROM SUNDAY AFTERNOON  
THROUGH TUESDAY EVENING FOR ZONES 340-346. (SEE LAXCFWLOX).  
PZ...SMALL CRAFT ADVISORY IN EFFECT UNTIL 9 PM PDT THIS EVENING  
FOR ZONE 645. (SEE LAXMWWLOX).  
SMALL CRAFT ADVISORY IN EFFECT UNTIL 3 AM PDT SATURDAY FOR  
ZONES 670-673-676. (SEE LAXMWWLOX).  
 

 
 

 
 
PUBLIC...MUNROE/SIRARD  
AVIATION...BLACK  
MARINE...LEWIS  
BEACHES...LEWIS  
SYNOPSIS...LEWIS  
 
WEATHER.GOV/LOSANGELES  
 
EXPERIMENTAL GRAPHICAL HAZARDOUS WEATHER OUTLOOK AT:  
HTTPS://WWW.WEATHER.GOV/ERH/GHWO?WFO=LOX  
 
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