228  
FXUS66 KLOX 211241  
AFDLOX  
 
AREA FORECAST DISCUSSION...UPDATED  
NATIONAL WEATHER SERVICE LOS ANGELES/OXNARD CA  
541 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)  
21/221 AM.  
 
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 FROM 400 AM TODAY THROUGH THE AFTERNOON HOURS  
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  
21/211 AM.  
 
FOR THE OUTER WATERS, MODERATE TO HIGH CONFIDENCE IN CURRENT  
FORECAST. AHEAD OF THE FRONT, THERE IS POTENTIAL FOR SHORT-LIVED  
SCA LEVEL WINDS THROUGH THIS MORNING, WITH BEST CHANCES FROM THE  
CHANNEL ISLANDS NORTHWARD. SEAS WILL BE NEAR 10 FEET THROUGH TODAY.  
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. AHEAD OF THE FRONT, THERE IS  
POTENTIAL FOR SHORT-LIVED SCA LEVEL WINDS THROUGH THIS MORNING,  
WITH BEST CHANCES FROM THE CHANNEL ISLANDS NORTHWARD. SEAS WILL BE  
NEAR 10 FEET THROUGH TODAY. 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. THIS MORNING, WINDS AND SEAS  
SHOULD MOSTLY REMAIN BELOW SCA LEVELS, BUT LOCALIZED GUSTS NEAR  
THE FRONT MAY BRIEFLY REACH SCA LEVELS. 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 FROM 10 AM THIS MORNING TO 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...PHILLIPS/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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