020  
FXUS66 KLOX 111539  
AFDLOX  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE LOS ANGELES/OXNARD CA  
839 AM PDT SAT OCT 11 2025  
   
SYNOPSIS  
11/358 AM.  
 
GUSTY NORTHERLY WINDS WILL INCREASE THROUGH TODAY, THEN SHIFT TO  
NORTHEAST AND WEAKEN ON SUNDAY. THIS WILL RESULT IN DRYING  
CONDITIONS THROUGH THE WEEKEND. A STORM SYSTEM WILL AFFECT THE  
AREA LATE MONDAY THROUGH WEDNESDAY, WITH MOST OF THE RAINFALL  
LIKELY ON TUESDAY. EXPECT WIDESPREAD LIGHT TO MODERATE RAIN WITH  
THE POTENTIAL FOR LOCALLY HEAVY SHOWERS AND THUNDERSTORMS.  
 
 
   
SHORT TERM (TDY-MON)  
11/838 AM.  
 
***UPDATE***  
 
LATEST SATELLITE AND SURFACE OBSERVATIONS INDICATE CLEAR SKIES  
ACROSS THE AREA EXCEPT FOR SOME CLOUDS/FOG ACROSS INTERIOR  
SECTIONS AND A LITTLE PATCH OFF THE VENTURA COUNTY COAST. CURRENT  
SOUNDING DATA INDICATES MARINE INVERSION AROUND 800 FEET IN DEPTH.  
AS FOR WINDS, CURRENTLY HAVE GUSTS 30-50 MPH ACROSS THE SANTA YNEZ  
RANGE AND SOME OF THE SAN LUIS OBISPO COUNTY FOOTHILLS.  
 
FORECAST-WISE FOR THE IMMEDIATE SHORT TERM, NO SIGNIFICANT ISSUES  
ARE EXPECTED. CURRENT STRATUS/FOG SHOULD DISSIPATE BY MID TO LATE  
MORNING WITH SUNNY SKIES FOR ALL AREAS THIS AFTERNOON. AS FOR  
WINDS, NORTHERLY PUSH WILL CONTINUE TO INCREASE THROUGH THE DAY AS  
PRESSURE GRADIENTS TIGHTEN BEHIND A WEAK DRY COLD FRONT PASSING  
THROUGH. SO, WIND ADVISORIES REMAIN IN EFFECT FOR MANY NORTHWEST  
TO NORTH WIND-PRONE AREAS THROUGH TONIGHT. GIVEN EXPECTED INCREASE  
IN NORTHERLY PUSH, THIS ADVISORIES LOOK ON TRACK AND NO CHANGES  
ARE ANTICIPATED AT THIS TIME.  
 
OVERALL, CURRENT FORECAST HAS GOOD HANDLE ON THE IMMEDIATE SHORT  
TERM. SO, NO SIGNIFICANT UPDATES ARE EXPECTED. FOR THE AFTERNOON  
FORECAST SUITE, ATTENTION WILL BE ON CONTINUED OFFSHORE WINDS  
THROUGH SUNDAY AND EARLY SEASON STORM EARLY NEXT WEEK.  
 
***FROM PREVIOUS DISCUSSION***  
 
THIS WEEKEND, WEATHER CONDITIONS WILL BE DRIVEN BY THE TROUGH  
ASSOCIATED WITH A LOW PRESSURE SYSTEM CENTERED OVER THE PACIFIC  
NORTHWEST. A POWERFUL JET ALOFT AND STRONG NORTH-TO-SOUTH SURFACE  
PRESSURE GRADIENTS WILL PRODUCE GUSTY WINDS. ALREADY NORTHERLY  
SUNDOWNER WINDS ARE OCCURING ACROSS SOUTHWESTERN SANTA BARBARA  
COUNTY (GUSTS 35-45 MPH). NORTHERLY WINDS WILL STRENGTHEN THROUGH  
TODAY, PEAKING THIS AFTERNOON INTO LATE TONIGHT. GUSTY WIND ARE  
EXPECTED FOR THE CENTRAL COAST, MOST OF SANTA BARBARA COUNTY  
(INCLUDING THE SOUTHEASTERN COASTAL PORTION), THE HWY 33 CORRIDOR,  
THE I-5 CORRIDOR, ANTELOPE VALLEY AND ADJACENT FOOTHILLS, SANTA  
CLARITA VALLEY, SANTA SUSANA MOUNTAINS, SANTA MONICA MOUNTAINS,  
AND THE WESTERN SAN FERNANDO VALLEY. WIND ADVISORIES HAVE BEEN  
ISSUED FOR THE AREAS EXPECTED TO SEE THE MOST SIGNIFICANT WINDS,  
WHERE GUSTS OF 30-50 MPH WILL BE COMMON. THERE IS A 30 PERCENT  
CHANCE THAT A HIGH WIND WARNING WILL BE NEEDED FOR THE I-5  
CORRIDOR TONIGHT.  
 
BY SUNDAY MORNING, AS THE TROUGH TRAVELS TO THE EAST, WINDS WILL  
BECOME MORE NORTHEASTERLY AND GENERALLY WEAKEN. GUSTS OF 20 TO 40  
MPH WILL BE POSSIBLE ACROSS MOUNTAINS AND FAVORED FOOTHILLS,  
ESPECIALLY THE WESTERN SAN GABRIEL MOUNTAINS, SANTA SUSANA  
MOUNTAINS, AND INTERIOR SANTA BARBARA COUNTY MOUNTAINS. THE WIND  
SHIFT WILL YIELD MOSTLY CLEAR SKIES, DRIER HUMIDITIES, AND BRIEFLY  
ELEVATED FIRE WEATHER CONDITIONS ON SUNDAY.  
 
THE TROUGH WILL BRING A COOLER AIRMASS TO THE REGION AND AS A  
RESULT TEMPERATURES WILL DROP COMPARED TO YESTERDAY. TEMPERATURES  
IN THE MID 70S TO MID 80S WILL BE COMMON THIS WEEKEND, EITHER  
NORMAL OR JUST BELOW NORMAL FOR THIS TIME OF YEAR. MONDAY, AS THE  
WEATHER PATTERN TRANSITIONS WITH THE APPROACHING STORM, DAYTIMES  
HIGHS WILL FALL DRAMATICALLY. MANY LOCATIONS WILL STRUGGLE TO  
REACH THE LOW 70S. RAINFALL CHANCES WILL BEGIN DURING THE DAY  
MONDAY FOR NORTHERN AREAS (MAINLY SAN LUIS OBISPO COUNTY), WITH  
THE CORE OF THE RAIN TRAVELING SOUTHWARD MONDAY NIGHT (SEE THE  
LONG TERM DISCUSSION).  
   
LONG TERM (TUE-FRI)  
11/356 AM.  
 
A STORM SYSTEM IS EXPECTED TO DROP DOWN EARLY NEXT WEEK, WITH THE  
CENTER OF THE LOW PASSING JUST NORTH OF THE REGION. CONFIDENCE IS  
NOW HIGH IN WIDESPREAD RAIN OCCURING, WITH THE MAJORITY OF THE  
RAIN FALLING ON TUESDAY. THERE CONTINUES TO BE SOME UNCERTAINTY IN  
THE TIMING AND EXACT TRACK OF THE UPPER LOW, WHICH MAY RESULT IN  
VARIATIONS IN RAIN TOTALS AS WELL AS THE CONVECTIVE/THUNDERSTORM  
POTENTIAL.  
 
THE WINDOW OF TIME WHERE RAIN IS MOST LIKELY (WITH THE HIGHEST  
RATES) IS 3 AM TO 9 PM TUESDAY. STORM TOTALS ARE EXPECTED TO BE  
THE HIGHEST FOR SAN LUIS OBISPO AND SANTA BARBARA COUNTIES AND THE  
VENTURA COUNTY MOUNTAINS, WHERE TOTALS BETWEEN 1.5 AND 2.5 INCHES  
WILL BE COMMON, AND 2 TO 4 INCHES FOR THE MOUNTAINS AND  
FOOTHILLS. SOUTHWESTERLY FLOW IS LIKELY TO PRODUCE ENHANCED RAIN  
ACROSS FAVORED TERRAIN. RAIN TOTALS WILL BE THE GREATEST FOR SANTA  
LUCIAS AND SOUTH- FACING SLOPES INCLUDING THE SANTA YNEZ AND  
WESTERN VENTURA COUNTY MOUNTAINS (20 PERCENT CHANCE TO EXCEED 4  
INCHES). FOR LA COUNTY AND THE REMAINDER OF VENTURA COUNTY,  
RAINFALL TOTALS ARE LIKELY TO RANGE FROM 0.5 TO 1.5 INCHES, WITH  
UP TO AROUND 2 INCHES POSSIBLE FOR SOUTH-FACING SLOPES OF THE  
SANTA MONICA AND SAN GABRIEL MOUNTAINS.  
 
RAIN RATES ARE GENERALLY EXPECTED TO PEAK AT AROUND 0.33  
INCHES/HOUR, HOWEVER THERE IS THE POTENTIAL FOR HIGHER RATES AND  
DAMAGING WINDS WITHIN STRONGER CELLS OR THUNDERSTORMS. THIS STORM  
IS VERY DYNAMIC WITH A HIGH AMOUNT OF WINDS SHEAR AND MODERATELY  
COLD TEMPERATURES ALOFT, THUS THERE IS A 10-20 PERCENT CHANCE OF  
THUNDERSTORMS PRIMARILY MONDAY NIGHT THROUGH TUESDAY FOCUSED OVER  
THE NORTHERN COASTAL WATERS AND SAN LUIS OBISPO AND SANTA BARBARA  
COUNTIES.  
 
A STORM OF THIS MAGNITUDE IS NOT UNHEARD OF FOR EARLY OCTOBER,  
BUT IT IS FAIRLY RARE. THE LAST TIME A STORM PRODUCED 1 INCH OF  
RAIN AT DOWNTOWN LA IN OCTOBER (WITHIN 1 CALENDER DAY) WAS IN  
2011, AND THE AVERAGE AMOUNT OF RAINFALL FOR THE ENTIRE MONTH OF  
OCTOBER IS 0.58 INCHES AT DTLA. TEMPERATURES WILL ALSO BE  
DRAMATICALLY COOLER, WITH MANY AREAS REMAINING BELOW 70 DEGREES  
TUESDAY AND WEDNESDAY. LATE NEXT WEEK, THERE IS A FAIR AMOUNT OF  
UNCERTAINTY IN THE FORECAST, THROUGH MORE RAIN AND UNSETTLED  
WEATHER WILL BE POSSIBLE.  
 
 
   
AVIATION  
11/1024Z.  
 
AROUND 07Z, THE MARINE LAYER DEPTH WAS AROUND 900 FT DEEP AT KLAX.  
THE TOP OF THE INVERSION WAS NEAR 1700 FEET WITH A TEMPERATURE OF  
24 DEGREES CELSIUS.  
 
MODERATE CONFIDENCE IN THE CURRENT FORECAST. THERE IS A LOW-TO-  
MODERATE CHANCE OF LIFR TO IFR CONDITIONS AT COASTAL TERMINALS AND  
KPRB THROUGH 16Z. OTHERWISE, VFR CONDITIONS ARE EXPECTED. PERIODS  
OF MODERATE TO STRONG LOW-LEVEL WIND SHEAR AND TURBULENCE ARE  
POSSIBLE NEAR KSBA THROUGH 10Z SUNDAY. PERIODS OF MODERATE TO  
STRONG LOW-LEVEL WIND SHEAR AND TURBULENCE ARE POSSIBLE AT ALL  
TERMINALS FROM 22Z THROUGH 10Z SUNDAY.  
 
KLAX...THERE IS A 40 PERCENT CHANCE OF IFR CONDITIONS BETWEEN 13Z  
AND 16Z. WIND IMPACTS COULD BE THE MAIN ISSUE. WHILE ANY EASTERLY  
WINDS ARE EXPECTED TO REMAIN BELOW 7 KNOTS THIS MORNING. THERE IS  
A HIGH CHANCE OF SIGNIFICANT NORTH WIND BETWEEN 8 AND 12 KNOTS  
WITH GUSTS POTENTIALLY UP TO 20 KNOTS FROM 02Z TO 06Z SUNDAY, THEN  
THERE IS MODERATE CHANCE OF NORTHEASTERLY WINDS BETWEEN 7 AND 10  
KNOTS THEREAFTER. PERIODS OF MODERATE LOW- LEVEL WIND SHEAR AND  
TURBULENCE ARE POSSIBLE NEAR KLAX BETWEEN 04Z AND 08Z SUNDAY.  
 
KBUR...VFR CONDITIONS ARE EXPECTED THROUGH THE PERIOD. PERIODS OF  
MODERATE TO STRONG LOW-LEVEL WIND SHEAR AND TURBULENCE ARE  
POSSIBLE NEAR KBUR BETWEEN 02Z AND 10Z SUNDAY.  
 
 
   
MARINE  
11/831 AM.  
 
FOR THE OUTER WATERS SOUTHWEST THROUGH NORTHWEST OF THE CHANNEL  
ISLANDS, INCLUDING THE NEARSHORE WATERS ALONG THE CENTRAL COAST,  
GALE FORCE WINDS WILL EXPAND ACROSS THE REMAINDER OF THE WATERS BY  
MID-AFTERNOON TODAY AND LAST THROUGH TONIGHT. HOWEVER, THE  
STRONGEST WINDS WILL BE FROM NEAR POINT CONCEPTION SOUTH TO SAN  
NICOLAS ISLAND, AND WILL CONTINUE INTO SUNDAY NIGHT WITH WINDS  
BRIEFLY DROPPING TO SMALL CRAFT ADVISORY (SCA) LATE TONIGHT INTO  
SUNDAY MORNING. OTHERWISE, SCA LEVEL WINDS AND SEAS WILL CONTINUE  
THROUGH AT LEAST EARLY SUNDAY MORNING, WITH A 40-60% CHANCE OF  
LINGERING INTO LATE SUNDAY NIGHT OR EARLY MONDAY MORNING. DUE TO  
THE GALES AND HAZARDOUS SEAS, INEXPERIENCED BOATERS SHOULD SEEK OR  
REMAIN IN SAFE HARBOR.  
 
INSIDE THE SOUTHERN CALIFORNIA BIGHT, SCA LEVEL WINDS ARE EXPECTED  
MAINLY ACROSS WESTERN PORTIONS OF THE BIGHT, AS WELL AS THE  
SOUTHERN PORTION OF THE SANTA BARBARA CHANNEL AND POSSIBLY ACROSS  
THE ANACAPA PASSAGE. SHORT- PERIOD HAZARDOUS SEAS COULD DEVELOP  
ACROSS THE SANTA BARBARA CHANNEL THIS EVENING, WITH WINDS AND SEAS  
POTENTIALLY REACHING VENTURA COUNTY HARBORS, SUCH AS VENTURA AND  
CHANNEL ISLANDS HARBOR DURING THIS TIME. THE STRONGEST WINDS ARE  
EXPECTED ACROSS THE WESTERN PORTION OF THE SANTA BARBARA CHANNEL,  
WHERE A MODERATE-TO- HIGH (30-50 PERCENT) CHANCE OF GALES EXISTS  
THIS AFTERNOON AND EVENING.  
 
WIDESPREAD SCA LEVEL SW WINDS AND SEAS, WITH A MODERATE CHANCE OF  
GALES IS EXPECTED BETWEEN MONDAY NIGHT AND TUESDAY NIGHT AS A  
COLD FRONT ASSOCIATED WITH A STORM SYSTEM MOVES OVER THE REGION.  
 
 
   
LOX WATCHES/WARNINGS/ADVISORIES  
 
CA...WIND ADVISORY REMAINS IN EFFECT FROM NOON TODAY TO 10 AM PDT  
SUNDAY FOR ZONES 88-350-352-353-375>379-381-383. (SEE LAXNPWLOX).  
WIND ADVISORY REMAINS IN EFFECT FROM NOON TODAY TO MIDNIGHT  
PDT TONIGHT FOR ZONES 340-341-346>348. (SEE LAXNPWLOX).  
WIND ADVISORY REMAINS IN EFFECT UNTIL 10 AM PDT SUNDAY FOR  
ZONES 349-351. (SEE LAXNPWLOX).  
PZ...SMALL CRAFT ADVISORY IN EFFECT UNTIL 3 PM PDT THIS AFTERNOON  
FOR ZONES 645-670. (SEE LAXMWWLOX).  
GALE WARNING IN EFFECT FROM 3 PM THIS AFTERNOON TO 3 AM PDT  
SUNDAY FOR ZONES 645-670. (SEE LAXMWWLOX).  
SMALL CRAFT ADVISORY IN EFFECT UNTIL 3 AM PDT MONDAY FOR ZONE  
650. (SEE LAXMWWLOX).  
SMALL CRAFT ADVISORY IN EFFECT FROM 3 PM THIS AFTERNOON TO 3  
AM PDT SUNDAY FOR ZONE 655. (SEE LAXMWWLOX).  
GALE WARNING IN EFFECT UNTIL 3 AM PDT MONDAY FOR ZONES  
673-676. (SEE LAXMWWLOX).  
 
 
 
 
 
PUBLIC...SCHOENFELD/THOMPSON  
AVIATION...HALL  
MARINE...HALL/LUND  
SYNOPSIS...RK/SCHOENFELD  
 
WEATHER.GOV/LOSANGELES  
 
EXPERIMENTAL GRAPHICAL HAZARDOUS WEATHER OUTLOOK AT:  
HTTPS://WWW.WEATHER.GOV/ERH/GHWO?WFO=LOX  
CLICK HERE TO GO TO PREVIOUS BULLETINS.
The Nexlab CA Page
Main Text Page