751
FXUS66 KLOX 250928
AFDLOX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LOS ANGELES/OXNARD CA
228 AM PDT TUE AUG 25 2026
SYNOPSIS
25/222 AM.
VERY HOT CONDITIONS WILL DOMINATE THE WEEK, WITH A HIGH RISK FOR
HEAT ILLNESS. PATCHY NIGHT THROUGH MORNING LOW CLOUDS AND LOCALLY
DENSE FOG WILL BE CONFINED TO SOME COASTAL AREAS. SIGNIFICANT
COOLING IS LIKELY OVER THE WEEKEND BUT IT WILL REMAIN WARM.
SHORT TERM (TDY-THU)
25/223 AM.
THE NEXT THREE DAYS WILL BE THE PEAK OF THE HEAT EVENT. A LARGE
AND VERY WARM UPPER HIGH WILL SIT ATOP OF NM/AZ AND WILL BRING
593-594 DAM HGTS TO THE AREA. ONSHORE GRADIENTS WILL BE WEAK AND
EVEN OFFSHORE FROM THE NORTH IN THE MORNINGS. THE MARINE LAYER
WILL BE SHALLOW AND WILL NOT XTND VERY FAR INLAND. MARINE LAYER
STRATUS WILL MOST LIKELY TO AFFECT THE CENTRAL COAST WHERE SOME
DENSE FOG IS POSSIBLE DUE TO THE SHALLOWNESS OF THE MARINE LAYER.
THERE ARE, HOWEVER, SOME SIGNALS THAT AN EDDY WILL DEVELOP IN
WHICH CASE THERE WILL BE MORE LOW CLOUDS SOUTH OF PT CONCEPTION.
MAX TEMPS WILL RANGE FROM 100 TO 106 DEGREES ALL THREE DAYS
ACROSS THE VLYS, LOWER MTNS ELEVATIONS AND FAR INTERIOR. THE
WESTERN SAN FERNANDO VLY WILL BE WARMER STILL WITH MAX TEMPS FROM
106 TO 112 DEGREES. THE LACK OF A STRONG ONSHORE GRADIENT IN THE
AFTERNOON WILL ALLOW THE INLAND AREAS OF THE CSTL REGIONS TO WARM
INTO THE 90S WITH EVEN SOME 100 TO 101 DEGREE READINGS POSSIBLE.
IN ADDITION THE THE DAY TIME HIGHS RUNNING 10 TO 15 DEGREES ABOVE
NORMAL THE OVERNIGHT LOW WILL ALSO BE 6 TO 12 DEGREES ABOVE NORMAL
AS SUBSIDENCE FROM THE UPPER HIGH SETS UP A STRONG AND HOT
INVERSION RIGHT AT VLY/FOOTHILL ELEVATIONS. ON WEDNESDAY A THE
USUAL ONSHORE PUSH ACROSS THE CENTRAL COAST WILL DISAPPEAR AND
MAX TEMPS THERE WILL RISE 8 TO 12 DEGREES WITH MANY LOCATIONS
REACHING INTO THE 90S.
ALMOST ALL OF THE AREA IS BLANKETED BY EXTREME HEAT WARNINGS AND
ADVISORIES. PLEASE SEE THE PRODUCT LAXNPWLOX FOR ALL DETAILS.
RESIDENTS NEED TO TAKE PRECAUTIONS TO AVOID HEAT RELATED DANGERS
WHEN OUTSIDE.
SUNDOWNER WINDS WILL AFFECT SOUTHERN SANTA BARBARA COUNTY THROUGH
THE WEEK, AND SHOULD INCREASE SOME EACH NIGHT. WIND ADVISORIES
MIGHT BE NEEDED TONIGHT AND/OR WEDNESDAY NIGHT.
LONG TERM (FRI-MON)
25/223 AM.
A SUBSTANTIAL TROF WILL MOVE INTO THE WEST COAST AND PUSH THE
UPPER HIGH TO THE SOUTH. THE FLOW WILL SLOWLY SWITCH TO THE SW
DURING THE PERIOD AND HGTS WILL FALL TO 588 DAM. SOME OFFSHORE
FLOW MAY PERSIST IN THE MORNING ESP FROM THE NORTH, BUT THE
AFTERNOON ONSHORE PUSH TO THE EAST WILL INCREASE.
MOST MAX TEMPS WILL FALL 1 TO 2 DEGREES ON FRIDAY (EXCEPT FOR THE
CENTRAL COAST WHERE BETTER ONSHORE FLOW WILL BRING 3 TO 6 DEGREES
OF COOLING). THIS SMALL AMOUNT OF COOLING WILL NOT BE ENOUGH TO
ELIMINATE THE HEAT RISK AND ALL WARNINGS AND ADVISORIES WILL
CONTINUE. LOOK FOR 5 TO 10 DEGREES OF COOLING ACROSS THE CSTS/VLY
ON SATURDAY AS THE TROF AND ONSHORE FLOW REALLY BEGIN TO AFFECT
THE WEATHER (THE MTNS AND FAR INTERIOR WILL SEE 2 TO 4 DEGREES OF
COOLING). ON SUNDAY ALL AREAS WILL COOL 3 TO 6 DEGREES AND THIS
WILL BRING MANY AREAS TO OR EVEN BELOW NORMAL MAX TEMPS. 2 TO 4
ADDITIONAL DEGREES OF COOLING IS LIKELY NEXT MONDAY AND THIS WILL
REDUCE COASTAL MAX TEMPS TO THE 70S (UPPER 60S/LOWER 70S CENTRAL
COAST) AND IN THE MID 80S TO MID 90S FOR THE VLYS.
AVIATION
25/0922Z.
AT 0830Z AT KLAX, THE MARINE LAYER WAS 500 FEET DEEP. THE TOP OF
THE INVERSION WAS 2000 FEET AND 31 C.
HIGH CONFIDENCE IN VFR CONDITIONS THROUGH AT LEAST TUESDAY KPRB,
KSBA, KBUR, KVNY, KPMD, AND KWJF.
FOR KSBP AND KSMX, TIMING OF FLIGHT CATEGORY CHANGES COULD BE +/-
2 HOURS OF CURRENT FORECAST.
CHANCES OF LIFR/IFR CEILINGS TONIGHT AT KOXR (20%) KCMA (20%)
KSMO (25%) KLAX (25%) KLGB (25%).
KLAX...MODERATE CONFIDENCE IN TAF WITH A 25 PERCENT CHC OF 3SM
BKN005 CONDS 12Z-16Z. NO SIGNIFICANT EASTERLY WIND COMPONENT IS
EXPECTED.
KBUR...HIGH CONFIDENCE IN CAVU TAF.
MARINE
25/223 AM.
FOR THE OUTER WATERS, HIGH CONFIDENCE IN CURRENT FORECAST. THIS
AFTERNOON THROUGH SATURDAY, SCA LEVEL WINDS ARE EXPECTED ACROSS
ALL OF THE OUTER WATERS. SEAS WILL REMAIN AT SCA LEVELS, INITIALLY
DUE TO SHORT PERIOD COMBINED SEAS, BUT APPROACHING 8 TO 10 FEET
BY THURSDAY.
FOR THE INNER WATERS NORTH OF POINT SAL, MODERATE TO HIGH
CONFIDENCE IN CURRENT FORECAST. LATE THIS AFTERNOON THROUGH LATE
TONIGHT THERE IS A 40-60% CHANCE OF SCA WINDS. FOR WEDNESDAY
THROUGH SATURDAY, THERE IS A 60-80% CHANCE OF SCA LEVEL WINDS IN
THE AFTERNOON AND EVENING HOURS. SHORT PERIOD SEAS WILL BE COMMON
THROUGHOUT THE WEEK, ESPECIALLY DURING THE AFTERNOON TO EVENING.
FOR THE INNER WATERS SOUTH OF POINT CONCEPTION, MODERATE TO HIGH
CONFIDENCE IN CURRENT FORECAST. FOR A MAJORITY OF THE SOUTHERN
INNER WATERS, HIGH CONFIDENCE IN WINDS AND SEAS REMAINING BELOW
SCA LEVELS THROUGH SATURDAY. THE ONLY EXCEPTION WILL BE THE
WESTERN HALF OF THE SANTA BARBARA CHANNEL WHERE THERE IS A 60-80%
CHANCE OF SCA LEVEL WINDS THROUGH SATURDAY IN THE LATE AFTERNOON
AND EVENING HOURS.
FIRE WEATHER
24/410 PM.
AN EXTENDED PERIOD OF VERY HOT AND DRY CONDITIONS WILL BRING WIDESPREAD
ELEVATED TO BRIEF CRITICAL FIRE WEATHER CONDITIONS AWAY FROM THE IMMEDIATE
COAST THROUGH THIS WEEKEND. THE COMBINATION OF TRIPLE DIGIT TEMPERATURES,
VERY DEEP MIXING HEIGHTS OF 12,000 TO 20,000 FEET, LOCALLY GUSTY WINDS,
LOW HUMIDITIES, AND FUELS APPROACHING CRITICAL LEVELS WILL BRING THE HIGHEST
RISK OF LARGE PLUME DOMINATED FIRES WITH RAPID FIRE SPREAD IN THE
INTERIOR MOUNTAINS AND ADJACENT FOOTHILLS OF LA, VENTURA, SANTA
BARBARA, AND SAN LUIS OBISPO COUNTIES, AS WELL AS THE CUYAMA
VALLEY, RESULTING IN THE RED FLAG WARNING ISSUANCE TUESDAY
THROUGH FRIDAY. THESE AREAS CAN EXPECT MINIMUM HUMIDITIES OF 8 TO
20 PERCENT, POOR OVERNIGHT RECOVERIES, AND LOCALLY GUSTY NORTHERLY
WINDS AT TIMES ACROSS THE INTERIOR MOUNTAINS (STRONGEST IN THE
I-5 AND HIGHWAY 33 CORRIDORS). THERE IS THE POSSIBILITY OF A
SLIGHT ENHANCEMENT TO THE NORTHERLY WINDS LATE THURSDAY NIGHT INTO
FRIDAY MORNING ACROSS THE INTERIOR MOUNTAINS, WHICH COULD RESULT
IN ISOLATED GUSTS UP TO 40 MPH IN THE I-5 CORRIDOR. THERE IS A
HISTORY OF LARGE PLUME DOMINATED FIRES THIS TIME OF YEAR WITH
SIMILAR WEATHER AND FUEL CONDITIONS, INCLUDING THE BRIDGE, BOBCAT,
AND STATIONS FIRES.
WEAK TO MODERATE SUNDOWNER WINDS WITH HOT AND DRY CONDITIONS WILL LIKELY
BRING ELEVATED TO BRIEF CRITICAL FIRE WEATHER CONDITIONS ACROSS SOUTHERN
SANTA BARBARA COUNTY THROUGH SATURDAY NIGHT, WITH TUESDAY AND SATURDAY EVENTS
LIKELY STRONGEST AND MOST WIDESPREAD. SUNDOWNER WIND EXPOSED AREAS COULD
SEE TEMPERATURES SOAR TO BETWEEN 90 AND 100 DEGREES WITH
HUMIDITIES FALLING TO BETWEEN 10 AND 25 PERCENT.
LOX WATCHES/WARNINGS/ADVISORIES
CA...HEAT ADVISORY IN EFFECT UNTIL 10 AM PDT THIS MORNING FOR
ZONES 38-87-88-349>358-362-366>376-378>380-548. (SEE LAXNPWLOX).
EXTREME HEAT WARNING IN EFFECT FROM 10 AM THIS MORNING TO 8
PM PDT FRIDAY FOR ZONES
38-87-88-349>358-362-366>376-378>383-548. (SEE LAXNPWLOX).
HEAT ADVISORY IN EFFECT FROM 10 AM WEDNESDAY TO 8 PM PDT
THURSDAY FOR ZONES 341-347-348. (SEE LAXNPWLOX).
HEAT ADVISORY IN EFFECT FROM 10 AM THIS MORNING TO 8 PM PDT
FRIDAY FOR ZONES 342>345. (SEE LAXNPWLOX).
RED FLAG WARNING IN EFFECT FROM 10 AM THIS MORNING TO 3 PM
PDT FRIDAY FOR ZONES 345-353-375>380. (SEE LAXRFWLOX).
PZ...SMALL CRAFT ADVISORY IN EFFECT FROM 3 PM THIS AFTERNOON TO 3
AM PDT WEDNESDAY FOR ZONE 645. (SEE LAXMWWLOX).
SMALL CRAFT ADVISORY IN EFFECT FROM 3 PM THIS AFTERNOON TO 3
AM PDT THURSDAY FOR ZONE 670. (SEE LAXMWWLOX).
SMALL CRAFT ADVISORY IN EFFECT UNTIL 3 AM PDT THURSDAY FOR
ZONES 673-676. (SEE LAXMWWLOX).
PUBLIC...RORKE
AVIATION...RORKE
MARINE...RAT/CILIBERTI
FIRE...GOMBERG
SYNOPSIS...RK
WEATHER.GOV/LOSANGELES
EXPERIMENTAL GRAPHICAL HAZARDOUS WEATHER OUTLOOK AT:
HTTPS://WWW.WEATHER.GOV/ERH/GHWO?WFO=LOX
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