473 
FXUS66 KLOX 011049
AFDLOX

SOUTHWEST CALIFORNIA AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LOS ANGELES/OXNARD CA
340 AM PDT MON OCT 1 2012

.SYNOPSIS...

WELL ABOVE NORMAL TEMPERATURES ARE EXPECTED THROUGH TUESDAY DUE TO 
OFFSHORE FLOW AT THE SURFACE. TEMPERATURES WILL PEAK TODAY...WITH 
THE STRONGEST OFFSHORE FLOW. ALTHOUGH REMAINING MUCH WARMER THAN 
NORMAL ON TUESDAY...MOST AREAS WILL COOL A FEW DEGREES AS ONSHORE 
FLOW STARTS TO RETURN. A GRADUAL COOLING TREND WILL CONTINUE THROUGH 
THE END OF THE WEEK.
 
&&

.SHORT TERM (TODAY-WED)...
LOW CLOUDS HAVE MADE A SURPRISING RETURN TO SOUTHERN L.A. COUNTY AS 
THE OFFSHORE FLOW HAS NOT ARRIVED WITH MUCH STRENGTH YET. NAM FCST 
OF SFC GRADIENTS WAS OFF AT 00Z BUT HAS ACCURATELY FCST THE CURRENT 
GRADIENTS. THE LOW CLOUDS WILL EVAPORATE SHORTLY AFTER SUNRISE AND 
SKIES WILL BE CLEAR FOR THE REMAINDER OF THE DAY. MAX TEMPS ARE THE 
BIG ISSUE TODAY. SUNDAY SAW A NICE 7 TO 10 DEGREE WARM UP ACROSS THE 
ENTIRE CWA AND CURRENT MDLS SHOW ANOTHER 2 TO 4 DEGREES OF WARMING 
AT 950 MB. OFFSHORE PUSH IS ALSO A LITTLE STRONGER THAN YDY. SO LOOK 
FOR ANOTHER 2 TO 6 DEGREES OF WARMING TODAY ACROSS MOST AREAS. THE 
FLOW SHOULD TURN WEAKLY ONSHORE IN THE AFTERNOON SO THE COASTAL 
AREAS WILL AT LEAST SOME SOME RELIEF LATER THIS AFTERNOON. IT WILL 
BE VERY DRY TODAY AND EVEN THOUGH THE AFTERNOON TEMPERATURES WILL 
BE VERY WARM THE HEAT INDICES WILL BE BELOW HEAT WARNING CRITERIA. 
THE CENTRAL COAST WILL BE VERY WARM TODAY AND THIS AREA WILL BE THE 
MOST ABOVE NORMAL.

OFFSHORE FLOW WILL CONTINUE TONIGHT AND THE SKIES SHOULD BE CLEAR. 
SOME BREEZY AREAS AND FOOTHILL AREAS WILL HAVE VERY WARM OVERNIGHT 
LOWS.

TUESDAY WILL BE SUNNY BUT THE MORNING OFFSHORE FLOW WILL BE WEAKER 
AND THE AFTERNOON ONSHORE FLOW WILL BE ABOUT 3 MB STRONGER. 950 MB 
TEMPS DROP AS WELL AND WHILE MAX TEMPS WILL STILL BE ABOVE NORMAL 
THEY WILL BE OFF BY 5 TO 7 DEGREES OFF FROM TODAYS VALUES.

JUST A SLOW CONTINUATION OF THE COOLING TREND ON WEDNESDAY. A 588 DM 
RIDGE EXTENDING FROM AN UPPER HIGH 300 MILES SOUTH OF KSAN WILL KEEP 
INLAND TEMPS WELL ABOVE NORMAL BUT BETTER ONSHORE FLOW WILL ALLOW 
THE COOLING TREND ACROSS THE COASTS AND COASTAL VLYS TO CONTINUE.

.LONG TERM (THU-SUN)...
ALL MEDIUM RANGE MDLS AGREE ON THE BASIC SYNOPTIC PATTERN THROUGH 
SATURDAY. THE RIDGE WILL HOLD STEADY OVER SOUTHERN CALIFORNIA BUT IT 
WILL SLOWLY WEAKEN DURING THE PERIOD AS AN UPPER LOW SLOWLY PRESSES 
INTO THE WEST COAST. ITS HARD TO DETERMINE WHEN THE MARINE LAYER 
WILL MAKE A COMEBACK BUT THERE LOOKS TO BE ENOUGH MORNING OFFSHORE 
FLOW TO KEEP THE CLOUDS AWAY TROUGH THURSDAY. BY FRIDAY THE 
CENTRAL COAST SHOULD SEE SOME LOW CLOUDS AND AS THE UPPER LOW 
APPROACHES SATURDAY MOST OF THE COASTS WILL HAVE MORNING LOW 
CLOUDS. TEMPS WILL NOT CHANGE MUCH THURSDAY AND FRIDAY BUT SATURDAY 
SHOULD SEE A GOOD COOL DOWN WITH THE MARINE LAYER AND LOWER HGTS.'

MDLS GREATLY DISAGREE WITH THE PLACEMENT OF THE UPPER LOW ON SUNDAY 
WITH THE EC LEADING THE CHARGE WITH A 559 DM LOW JUST WEST OF SANTA 
MARIA THE GFS BRINGS A 562 LOW WEST OF EUREKA. THE EC DOES BRING 
RAIN TO THE AREA BUT NOT BITING ON THIS JUST YET. INCREASED THE 
CLOUDS AND LOWERED TEMPS SOME MORE.

&&

.AVIATION...

01/1100Z

CLEAR SKIES EVERYWHERE TODAY EXCEPT FOR LIFR CONDS BETWEEN KLAX AND 
KLGB...THESE CLOUDS WILL DISSIPATE BY 14Z. 

KLAX...A 40 PERCENT CHANCE OF LIFR CIGS THROUGH 14Z. THEN HIGH 
CONFIDENCE IN CAVU TAF.

KBUR...VERY HIGH CONFIDENCE IN CAVU TAF.

&&

.FIRE WEATHER...

FIRE DANGER ON THE INCREASE ACROSS SOUTHWEST CALIFORNIA TODAY DUE TO 
LOCALLY GUSTY WINDS COMBINING WITH HOT TEMPERATURES AND WIDESPREAD 
HUMIDITIES BETWEEN 8 AND 15 PERCENT ACROSS INLAND AREAS. FIRE DANGER 
IS EXPECTED TO PEAK ON MONDAY WHEN RECORD BREAKING TRIPLE DIGIT 
HEAT  AND WIDESPREAD SINGLE DIGIT HUMIDITIES WILL COMBINE WITH VERY 
DRY FUELS. THE MOST CRITICAL FIRE WEATHER CONDITIONS ARE EXPECTED 
ACROSS THE MOUNTAINS OF LOS ANGELES AND VENTURA COUNTIES AND SANTA 
CLARITA VALLEY...WHERE A RED FLAG WARNING IS IS IN EFFECT. THESE 
AREAS WILL LIKELY SEE OFFSHORE WINDS GUSTING TO BETWEEN 20 AND 30 
MPH ON MONDAY. WHILE CONDITIONS ON TUESDAY WILL NOT BE QUITE AS HOT 
AND DRY DUE TO INCREASING ONSHORE FLOW...AREAS UNDER THE RED FLAG 
WARNING COULD STILL SEE TEMPERATURES ABOVE 100 DEGREES AND 
HUMIDITIES AROUND 10 PERCENT ON TUESDAY AFTERNOON...COINCIDING WITH 
ONSHORE WINDS GUSTING TO AROUND 25 MPH. IN ADDITION...VERY WARM 
OVERNIGHT LOWS AND VERY POOR HUMIDITY RECOVERIES EXPECTED THE NEXT 
COUPLE OF NIGHT ACROSS PORTIONS OF THE MOUNTAINS AND FOOTHILLS.

A FIRE WEATHER WATCH IS NOW IN EFFECT FOR THE SANTA MONICA MOUNTAINS 
ON TUESDAY...WHERE THERE IS STILL THE POTENTIAL FOR BRIEF CRITICAL 
FIRE WEATHER CONDITIONS DURING THE AFTERNOON HOURS AS ONSHORE WINDS 
GUSTING TO 25 MPH WILL BE POSSIBLE. WHILE AREAS UNDER A RED FLAG 
WARNING AND FIRE WEATHER WATCH WILL HAVE THE GREATEST THREAT FOR 
LARGE FIRE ACTIVITY...REMAINING AREAS OF SOUTHWEST CALIFORNIA HAVE 
ELEVATED FIRE DANGER DUE TO THE WIDESPREAD HOT AND DRY CONDITIONS 
COMBINED WITH VERY DRY FUELS. 

&&

.LOX WATCHES/WARNINGS/ADVISORIES...
RED FLAG WARNING (SEE LAXRFWLOX).
FIRE WEATHER WATCH (SEE LAXRFWLOX).
HIGH RIP CURRENT RISK (SEE LAXSRFLOX).
SPECIAL WEATHER STATEMENT (SEE LAXSPSLOX).

&&

$$

PUBLIC...RORKE
AVIATION...HALL
SYNOPSIS...SUKUP

WWW.WEATHER.GOV/LOSANGELES