356  
FXUS66 KLOX 211634  
AFDLOX  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE LOS ANGELES/OXNARD CA  
934 AM PDT TUE APR 21 2026  
   
SYNOPSIS
 
21/222 AM.  
 
LIGHT TO MODERATE RAIN IS EXPECTED THROUGH TODAY, ALTHOUGH  
LOCALLY HEAVIER RAIN IS POSSIBLE OVER THE NORTHERN AREA. THE  
HIGHEST RAIN AMOUNTS ARE EXPECTED FOR SAN LUIS OBISPO COUNTY,  
HOWEVER WITH MINIMAL IMPACTS. MUCH COOLER WEATHER IS ON TAP  
THROUGH WEDNESDAY. GUSTY SOUTHWEST WINDS ARE EXPECTED TODAY,  
FOLLOWED BY WEST TO NORTHWEST WINDS WEDNESDAY THROUGH FRIDAY.  
 

 
   
SHORT TERM (TDY-THU)
 
21/932 AM.  
 
***UPDATE***  
 
RAINFALL RATES (GENERALLY UNDER ONE THIRD OF AN INCH PER HOUR)  
AND AMOUNTS (GENERALLY LESS THAN ONE INCH) HAVE BEEN TRACKING  
WELL WITH FORECAST SO FAR. AS EXPECTED THE FRONT IS WEAKENING  
SOUTH OF POINT CONCEPTION WITH MOST AREAS EXPECTED LESS THAN ONE  
QUARTER OF AN INCH FOR MOST OF VENTURA AND LOS ANGELES COUNTIES.  
 
THERE CONTINUES TO BE A 10-20 PERCENT CHANCE OF THUNDERSTORMS  
FOR SAN LUIS OBISPO COUNTY, HIGHEST NORTHERN SECTION. WE WERE  
SEEING THUNDERSTORMS WELL OFF SHORE WITH SHALLOW CONVECTION CLOSER  
TO THE COAST THAT MAY STRENGTHEN AS IT MOVES ASHORE AND ENCOUNTERS  
DAYTIME HEATING OVER LAND. BRIEF HEAVY DOWNPOURS, GUSTY WINDS UP  
TO 40 MPH, AND CLOUD-TO- GROUND LIGHTNING ARE THE MOST LIKELY  
HAZARDS WITH ANY THUNDERSTORMS.  
 
TODAY, WE WILL TAKE A LOOK AT POSSIBLE WIND ADVISORIES FOR THE  
WEDNESDAY TO EARLY THURSDAY TIME FRAME FOR INTERIOR MOUNTAINS TO  
POTENTIALLY SOME COASTAL SECTIONS, ESPECIALLY IN VENTURA COUNTY.  
THE STORM DOOR MAY REMAIN OPEN INTO EARLY MAY WITH MAINLY LIGHT  
RAIN POTENTIAL AT SOME POINT THIS WEEKEND AND AGAIN EARLY OR  
MIDDLE PART OF NEXT WEEK.  
 
***FROM PREVIOUS DISCUSSION***  
 
A MODERATE LATE SEASON STORM WILL MOVE ACROSS SOUTHWEST CALIFORNIA  
THROUGH TODAY. MOST OF THE RAIN WILL OCCUR THIS MORNING THROUGH  
THIS EVENING, HOWEVER SOME LIGHT SHOWERS MAY LINGER OVER THE  
NORTHERN MOUNTAIN SLOPES TONIGHT INTO EARLY WEDNESDAY. THE  
HIGHEST RAIN AMOUNTS WILL COVER SAN LUIS OBISPO AND SANTA BARBARA  
COUNTIES, AS THE FRONT WILL WEAKEN AS IT MOVES OVER VENTURA COUNTY  
AND ESPECIALLY LOS ANGELES COUNTY. THERE WILL BE A SLIGHT CHANCE  
OF THUNDERSTORMS FOCUSED THIS AFTERNOON OVER SAN LUIS OBISPO  
COUNTY. WHILE THERE IS A CHANCE OF LOCALLY HEAVIER RAIN AT TIMES  
ACROSS MUCH OF THE AREA, THIS WILL BE ENHANCED OVER SLO COUNTY DUE  
TO THE CONVECTIVE CHANCES.  
 
RAINFALL TOTALS WILL RANGE FROM ONE QUARTER OF AN INCH TO AROUND AN  
INCH FOR SAN LOUIS OBISPO (EXCEPT FOR 1.5-2 INCHES FOR THE COASTAL  
HILLS) AND SANTA BARBARA COUNTIES, TO 0.5 INCH IN THE VENTURA  
MOUNTAINS, TO ONE THIRD OF AN INCH OR LESS ELSEWHERE. BRIEF  
HEAVY DOWNPOURS, GUSTY WINDS UP TO 40 MPH, AND CLOUD-TO- GROUND  
LIGHTNING ARE THE MOST LIKELY HAZARDS WITH ANY THUNDERSTORMS. PEAK  
RAINFALL RATES WILL BE AROUND A QUARTER OF AN INCH PER HOUR OR  
LESS, ALTHOUGH RATES UP TO 0.5 INCHES PER HOUR MANY OCCUR IN ANY  
THUNDERSTORMS OR ALONG THE FRONTAL BOUNDARY. MINOR FLOODING IS  
POSSIBLE IF THESE RATES OCCUR, ESPECIALLY IN LOW LYING URBAN  
AREAS OR NEAR RECENT BURN SCARS.  
 
AS FOR WINDS, GUSTY SOUTH TO SOUTHWEST WINDS ARE EXPECTED AHEAD OF  
AND NEAR THE FRONT, GENERALLY 20 TO 40 MPH. STRONGER SW WINDS  
WILL AFFECT THE ANTELOPE VALLEY AND SAN GABRIEL MOUNTAINS FROM  
AROUND 10 AM TODAY THROUGH THIS EVENING. AFTER THIS TIME, WINDS  
WILL SHIFT TO THE WEST TO NORTHWEST AND REMAIN GUSTY INTO  
THURSDAY. THESE WINDS WILL BE STRONGEST OVER THE MOUNTAINS AND  
INTERIOR, BUT MAY AFFECT SOME COASTAL SECTIONS AT TIMES.  
   
LONG TERM (FRI-MON)
 
21/540 AM.  
 
FRIDAY WILL OFFER ANOTHER DAY OF NEAR NORMAL TEMPERATURES MOSTLY  
IN THE 70S. ANOTHER STORM SYSTEM IS LIKELY TO IMPACT THE AREA  
THAT WILL LEAD TO A COOLING TREND OVER THE WEEKEND, DROPPING  
TEMPERATURE BACK INTO THE 60S. THERE IS A 30-50 PERCENT CHANCE OF  
MAINLY LIGHT RAIN FOCUSED ACROSS THE FOOTHILLS TO INTERIOR  
SOMETIME THIS WEEKEND THANKS TO MOIST UPSLOPE FLOW OVER THE  
MOUNTAINS AND LIMITED INSTABILITY. THE STORM ENERGY IS COMING FROM  
THE SOUTHWEST TO WEST AND IS WEAK SO SIGNIFICANT WIND CONCERNS  
ARE UNLIKELY, BUT IT DOES LEND ITSELF TO BELOW NORMAL FORECAST  
CONFIDENCE. RAIN CHANCES AND UNSETTLED WEATHER MAY CONTINUE  
THROUGH THE END OF THE MONTH.  
 

 
   
AVIATION
 
21/1207Z.  
 
AT 0743Z AT KLAX, THE MARINE LAYER WAS 1500 FT WITH A WEAK  
INVERSION UP TO 2100 FT WITH A MAXIMUM TEMPERATURE OF 13 C.  
 
LOW TO MODERATE CONFIDENCE, AS A FRONT WITH A LINE OF SHOWERS  
MOVES FROM NORTH TO THE SOUTH ACROSS THE AREA. TIMING OF RAIN AND  
FLIGHT CATEGORY CHANGES COULD BE +/- 2 HOURS OF CURRENT FORECASTS.  
THERE WILL BE A 10-15% CHANCE OF THUNDERSTORMS THROUGH 00Z WED AT  
KPRB, KSBP, AND KSMX.  
 
KLAX...HIGH CONFIDENCE IN RETURN OF CIG/VSBY RESTRICTIONS, BUT  
TIMING OF RAIN AND FLIGHT CATEGORY CHANGES COULD BE +/- 2 HOURS  
OF CURRENT FORECAST. THERE IS A 30% CHANCE FOR AN EASTERLY WIND  
COMPONENT OF AROUND 5-6 KT THROUGH 18Z.  
 
KBUR...HIGH CONFIDENCE IN RETURN OF CIG/VSBY RESTRICTIONS, BUT  
TIMING OF RAIN AND FLIGHT CATEGORY CHANGES COULD BE +/- 2 HOURS  
OF CURRENT FORECAST.  
 

 
   
MARINE
 
21/712 AM.  
 
FOR THE OUTER WATERS, MODERATE TO HIGH CONFIDENCE IN CURRENT  
FORECAST. FOR TODAY, SMALL CRAFT ADVISORY (SCA) LEVEL SEAS WILL  
CONTINUE ACROSS PZZ670 WITH WINDS AND SEAS REMAINING BELOW SCA  
LEVELS ACROSS PZZ673/676. FOR WEDNESDAY THROUGH FRIDAY, HIGH  
CONFIDENCE IN COMBINATION OF SCA LEVEL NORTHWESTERLY WINDS AND  
SEAS WITH A 20-30% CHANCE OF GALE FORCE WINDS SOUTH OF POINT  
CONCEPTION WEDNESDAY NIGHT. FOR SATURDAY, HIGH CONFIDENCE IN WINDS  
AND SEAS REMAINING BELOW SCA LEVELS.  
 
FOR THE INNER WATERS NORTH OF POINT SAL, MODERATE TO HIGH  
CONFIDENCE IN CURRENT FORECAST. FOR TODAY, THERE IS A 60-70%  
CHANCE OF A COMBINATION OF SCA LEVEL WINDS AND SEAS. FOR WEDNESDAY  
THROUGH FRIDAY, THERE IS A 60-80% CHANCE OF SCA LEVEL NORTHWESTERLY  
WINDS, MAINLY IN THE AFTERNOON AND EVENING HOURS. ON SATURDAY,  
HIGH CONFIDENCE IN WINDS AND SEAS REMAINING BELOW SCA LEVELS.  
 
FOR THE INNER WATERS SOUTH OF POINT CONCEPTION, MODERATE TO HIGH  
CONFIDENCE IN CURRENT FORECAST. FOR TODAY, THERE IS A 20% CHANCE  
OF SCA LEVEL WINDS ALONG THE COLD FRONT. ON WEDNESDAY, HIGH CONFIDENCE  
IN SCA LEVEL NORTHWESTERLY ACROSS ALL THE SOUTHERN INNER WATERS  
WITH A 20% CHANCE OF GALE FORCE WINDS. FOR THURSDAY THROUGH  
FRIDAY, WINDS AND SEAS ARE EXPECTED TO REMAIN BELOW SCA LEVELS FOR  
MOST AREAS. THE ONLY EXCEPTION WILL BE THE WESTERN HALF OF THE  
SANTA BARBARA CHANNEL WITH A 60-80% CHANCE OF SCA LEVEL WINDS. ON  
SATURDAY, HIGH CONFIDENCE IN WINDS AND SEAS REMAINING BELOW SCA  
LEVELS FOR ALL OF THE SOUTHERN INNER WATERS.  
 
A COLD FRONT WILL SWEEP ACROSS THE COASTAL WATERS THROUGH TODAY.  
WITH THIS FRONTAL PASSAGE, THERE WILL BE A 20% CHANCE OF  
THUNDERSTORMS ACROSS THE COASTAL WATERS NORTH OF POINT CONCEPTION.  
ANY THUNDERSTORMS THAT DEVELOP MAY PRODUCE BRIEF HEAVY RAIN,  
GUSTY WINDS AND LOCALLY ROUGH SEAS.  
 

 
   
LOX WATCHES/WARNINGS/ADVISORIES
 
 
CA...WIND ADVISORY IN EFFECT UNTIL 10 PM PDT THIS EVENING FOR  
ZONES 378>383. (SEE LAXNPWLOX).  
PZ...SMALL CRAFT ADVISORY IN EFFECT UNTIL 6 PM PDT THIS EVENING  
FOR ZONES 645-670. (SEE LAXMWWLOX).  
 

 
 

 
 
PUBLIC...CILIBERTI/SCHOENFELD  
AVIATION...SCHOENFELD  
MARINE...RAT  
SYNOPSIS...MW/RS/CC  
 
WEATHER.GOV/LOSANGELES  
 
EXPERIMENTAL GRAPHICAL HAZARDOUS WEATHER OUTLOOK AT:  
HTTPS://WWW.WEATHER.GOV/ERH/GHWO?WFO=LOX  
 
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