077
FXUS66 KLOX 122102
AFDLOX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LOS ANGELES/OXNARD CA
202 PM PDT SUN OCT 12 2025
SYNOPSIS
12/329 AM.
GUSTY NORTHEAST WILL WEAKEN THROUGH TODAY WITH MOSTLY CLEAR SKIES
EXPECTED TODAY. A WINTER LIKE STORM SYSTEM WILL MOVE ACROSS THE
AREA LATE MONDAY THROUGH WEDNESDAY, WITH MOST OF THE RAINFALL
LIKELY MONDAY NIGHT THROUGH TUESDAY AFTERNOON. EXPECT WIDESPREAD
LIGHT TO MODERATE RAIN WITH POTENTIAL FOR LOCALLY HEAVY SHOWERS
AND THUNDERSTORMS, AND GUSTY SOUTHERLY WINDS.
SHORT TERM (TDY-WED)
12/200 PM.
OVERALL, 12Z MODELS IN GOOD SYNOPTIC AGREEMENT THROUGH THE SHORT
TERM PERIOD. UPPER LOW DEVELOPS OFF THE NORTHERN CALIFORNIA COAST
ON MONDAY, DROPS SOUTH/EAST INTO CENTRAL CALIFORNIA ON TUESDAY,
THEN INTO THE GREAT BASIN ON WEDNESDAY. WITH THIS PATTERN, A
RATHER DYNAMIC WEATHER PATTERN IS STILL ON TRACK FOR THE AREA
MONDAY NIGHT THROUGH TUESDAY NIGHT, WITH THINGS QUIETING DOWN ON
WEDNESDAY.
WIND...
NORTHEASTERLY WINDS, GUSTING 20-35 MPH, CONTINUE THIS AFTERNOON,
BUT WILL CONTINUE TO DIMINISH INTO THE EVENING AS OFFSHORE
PRESSURE GRADIENTS CONTINUE TO DECREASE. SO, NO ISSUES ARE
EXPECTED.
HOWEVER, FOR MONDAY AND TUESDAY, EXPECT A DRAMATIC INCREASE IN
SOUTH TO SOUTHWEST WINDS AS THE UPPER LOW IMPACTS THE AREA. WINDS
WILL FIRST INCREASE ACROSS THE DESERTS AND INTERIOR SECTIONS ON
MONDAY THEN INCREASE WEST OF THE MOUNTAINS MONDAY NIGHT AND
TUESDAY. AT THIS TIME, ADVISORY-LEVEL WINDS ARE LIKELY ACROSS THE
DESERTS AND INTERIOR SECTIONS (WITH A CHANCE OF WARNING LEVEL
WINDS ACROSS THE LA MOUNTAINS AND ANTELOPE VALLEY FOOTHILLS). FOR
COASTAL AND VALLEY AREAS, THERE IS A 30-50% CHANCE OF WIDESPREAD
ADVISORY LEVEL WINDS MONDAY NIGHT AND TUESDAY.
PRECIPITATION...
ALL SYSTEMS ARE STILL A BIG "GO" FOR THE STORM MONDAY NIGHT
THROUGH TUESDAY NIGHT. BASED ON LATEST GUIDANCE, EXPECTED RAINFALL
TOTALS HAVE ADJUSTED FROM PREVIOUS THINKING. RIGHT NOW, COASTAL
AND VALLEY AREAS CAN EXPECT 0.75-1.50 INCHES OF RAINFALL WITH 1.50
TO 3.50 INCHES ACROSS THE MOUNTAINS/FOOTHILLS. OF COURSE, GIVEN
THE SOUTHERLY FLOW, SOME FAVORED UPSLOPE AREAS COULD RECEIVE EVEN
HIGHER AMOUNTS.
AS FOR RAINFALL RATES, GENERALLY WILL BE EXPECTING HOURLY RATES
OF 0.25-0.50 INCHES. HOWEVER, HIGH RESOLUTION MODELS ARE STILL
INDICATING THE POTENTIAL FOR A QLCS-TYPE FEATURE ON TUESDAY WHICH
WOULD GENERATE HIGHER RATES OF 0.50-1.00 INCHES PER HOUR OR EVEN
HIGHER. ADDITIONALLY, SUB-HOURLY RATES COULD BE QUITE INTENSE. SO,
GIVEN THE POTENTIAL FOR RAIN RATES TO MEET/EXCEED USGS THRESHOLDS
FOR THE BURN SCARS, A FLOOD WATCH WILL BE IN EFFECT FOR THE BURN
AREAS (SEE LAXFFALOX FOR DETAILS). THERE WILL BE THE POTENTIAL FOR
SIGNIFICANT MUD/DEBRIS FLOW ISSUES.
AS FOR THUNDERSTORMS, THE RISK STILL REMAINS FOR THE AREA. LOOKING
AT THE MODEL SOLUTIONS, THE SETUP IS LOOKING MORE CONDUCIVE FOR
WIDESPREAD THUNDERSTORM POTENTIAL FOR ALL AREAS MONDAY NIGHT AND
TUESDAY. ALTHOUGH CAPE VALUES ARE NOT IMPRESSIVE, THE POTENTIAL
DIFFLUENT FLOW ALOFT, STRONG JET DYNAMICS AND LOW LEVEL WIND
SHEAR WILL BRING THE POSSIBILITY OF STRONG THUNDERSTORMS (GUSTY
WINDS, HAIL AND HEAVY RAIN) ALONG WITH WATERSPOUTS/WEAK TORNADOES.
FOR REFERENCE, THE SETUP IS LOOKING SIMILAR TO CONDITIONS
INDICATED BY THE HALES STUDY FOR SOUTHWESTERN CALIFORNIA SEVERE
WEATHER.
FINALLY, THERE STILL LOOKS TO BE THE POTENTIAL FOR SOME SNOWFALL
ACCUMULATIONS AT THE HIGHER ELEVATIONS. BASED ON THICKNESS AND
WET BULB ZERO FORECASTS, SNOW LEVELS LOOK TO DROP INTO THE
5500-7000 FOOT RANGE ON TUESDAY (BUT LOCALLY LOWER WITH ANY
SIGNIFICANT CONVECTION). SO, SEVERAL INCHES OF SNOWFALL
ACCUMULATION WILL BE LIKELY ABOVE 6000 FEET. GIVEN THE STRONG
SOUTHERLY WINDS ANTICIPATED, WINTER STORM CRITERIA CONDITIONS
COULD DEVELOP. WILL LET THE NEXT COUPLE OF SHIFTS LOOK AT THE NEXT
SUITE OF MODEL RUNS TO MAKE THE FINAL DETERMINATION FOR ANY
WINTER PRODUCTS.
LONG TERM (THU-SUN)
12/200 PM.
FOR THE EXTENDED, 12Z MODELS CONTINUE TO EXHIBIT GOOD SYNOPTIC
AGREEMENT. AT UPPER LEVELS, RIDGE GRADUALLY BUILDS OVER THE
EASTERN PACIFIC THURSDAY THROUGH SATURDAY, BEFORE WEAKENING ON
SUNDAY AS A TROUGH MOVES ACROSS NORTHERN CALIFORNIA/PACIFIC
NORTHWEST. NEAR THE SURFACE, WEAK DIURNAL GRADIENTS WILL PREVAIL.
FORECAST-WISE, NO SIGNIFICANT ISSUES ARE EXPECTED. FOR THURSDAY
THROUGH SATURDAY, DRY CONDITIONS ARE EXPECTED ALONG WITH A WARMING
TREND. AT TIMES, THERE COULD BE SOME OFFSHORE WINDS ACROSS THE
AREA, BUT ANY WINDS LOOK TO BE WEAK (IF THEY DO DEVELOP). ON
SUNDAY, AS THE TROUGH ROLLS ACROSS THE WEST COAST, COOLER
CONDITIONS ARE ANTICIPATED ALONG WITH THE POSSIBILITY OF SOME
ADDITIONAL RAINFALL (BUT CONFIDENCE IN THAT POTENTIAL REMAINS VERY
LOW).
AVIATION
12/1303Z.
AT 1227Z AT KLAX, THE MARINE LAYER WAS 600 FT DEEP. THE TOP OF THE
INVERSION WAS AT 1100 FT WITH A TEMPERATURE OF 17 C.
OVERALL, GOOD CONFIDENCE IN 12Z TAF PACKAGE.
GENERALLY EXPECTING VFR CONDITIONS THROUGH THE PERIOD.
THE EXCEPTION IS AT KLGB, KSMO, & KLAX WHERE LIFR CONDITIONS ARE
POSSIBLE AT TIMES THROUGH 17Z SUN, AND MVFR CIGS ARE POSSIBLE
TOWARDS END OF FCST PERIOD.
MODERATE CONFIDENCE IN WIND FORECASTS.
KLAX...MODERATE CONFIDENCE IN 12Z TAF. THROUGH 17Z SUNDAY,
EXPECT FLUCTUATIONS BETWEEN FEW/SCT 003-005 & BKN/OVC 003-005.
HIGHEST CHANCE FOR PERSISTENT LIFR CIGS LIKELY TO FALL BETWEEN
14Z TO 16Z SUN. GOOD CONFIDENCE IN CLEARING BY 17Z (+/- 1 HR).
MVFR CIGS ~015 LIKELY (60%) TO ARRIVE SOMETIME AFTER 08Z MON.
THERE IS A 60-70% CHANCE OF EAST WIND COMPONENT REACHING 7-8 KNOTS
FROM 08Z MON THRU 18Z MON.
KBUR...HIGH CONFIDENCE IN 12Z TAF. VFR CONDITIONS EXPECTED THRU
FORECAST PERIOD.
MARINE
12/738 AM.
FOR THE OUTER WATERS SOUTHWEST THROUGH NORTHWEST OF THE CHANNEL
ISLANDS, INCLUDING THE NEARSHORE WATERS ALONG THE CENTRAL COAST,
WINDS HAVE SUBSIDED BELOW GALE FORCE ACROSS THE NORTHERN WATERS
AND THUS THE GALE WARNING HAS BEEN REPLACED WITH A SMALL CRAFT
ADVISORY (SCA) (PZZ670/645). WINDS WILL REMAIN STRONG FROM POINT
CONCEPTION SOUTH TO SAN NICOLAS ISLAND, THUS GALE WARNING REMAINS
IN EFFECT ACROSS THIS AREA THROUGH LATE TONIGHT (PZZ673/676). SCA
CONDITIONS ARE LIKELY TO LINGER IN SOME FASHION THROUGH MONDAY
MORNING.
FOR THE INNER WATERS SOUTH OF POINT CONCEPTION, WINDS ARE EXPECTED
TO INCREASE TO SCA LEVELS THIS AFTERNOON ACROSS WESTERN & SOUTHERN
PORTIONS OF THE SANTA BARBARA CHANNEL. LIKELY REACHING THE ANACAPA
PASSAGE BY EARLY EVENING. GOOD CONFIDENCE THAT WINDS CALM TO BELOW
SCA LEVELS BY EARLY MONDAY MORNING.
MONDAY EVENING THROUGH TUESDAY NIGHT, A STORM SYSTEM AND ASSOCIATED
COLD FRONT WILL MOVE ACROSS THE REGION. THIS WILL BRING A 20-40%
CHANCE OF THUNDERSTORMS TO THE SANTA BARBARA CHANNEL, WEST PAST THE
CHANNEL ISLANDS, AND NORTHWARD TO THE SAN LUIS OBISPO COUNTY LINE.
FOR THE WATERS SOUTH OF THE SANTA BARBARA CHANNEL, INCLUDING THE
WATERS NEARSHORE LA AND ORANGE COUNTIES, THERE IS A 10-20% CHANCE
OF THUNDERSTORMS.
ANY THUNDERSTORM THAT FORMS MAY BE CAPABLE OF FREQUENT CLOUD TO
SURFACE LIGHTNING, GUSTY AND ERRATIC WINDS, SMALL HAIL, AND EVEN A
WATERSPOUT. ADDITIONALLY, WIDESPREAD SCA LEVEL SW WINDS AND SEAS,
WITH A MODERATE CHANCE OF GALES BETWEEN MONDAY NIGHT AND TUESDAY
NIGHT DUE TO THE AFOREMENTIONED STORM.
LOX WATCHES/WARNINGS/ADVISORIES
CA...FLOOD WATCH IN EFFECT FROM MONDAY EVENING THROUGH TUESDAY
AFTERNOON FOR ZONES
38-88-342-344-345-348-353-355-358-362-368>375-377>380-548. (SEE LAXFFALOX).
PZ...SMALL CRAFT ADVISORY IN EFFECT UNTIL 9 AM PDT MONDAY FOR
ZONES 645-670. (SEE LAXMWWLOX).
SMALL CRAFT ADVISORY IN EFFECT UNTIL 3 AM PDT MONDAY FOR ZONE
650. (SEE LAXMWWLOX).
GALE WARNING IN EFFECT UNTIL 3 AM PDT MONDAY FOR ZONES
673-676. (SEE LAXMWWLOX).
PUBLIC...THOMPSON
AVIATION...BLACK
MARINE...BLACK/LUND
SYNOPSIS...SCHOENFELD
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