172 
FXUS66 KLOX 270930
AFDLOX

SOUTHWEST CALIFORNIA AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LOS ANGELES/OXNARD CA
230 AM PDT SAT OCT 27 2012

.SYNOPSIS...
SOME LINGERING GUSTY OFFSHORE WINDS CAN BE EXPECTED THROUGH TODAY.  
OTHERWISE...MOSTLY CLEAR SKIES AND ABOVE NORMAL TEMPERATURES WILL 
PREVAIL THROUGH TUESDAY AS HIGH PRESSURE LINGERS OVER THE REGION. 
MARINE LAYER CLOUDS WILL INCREASE BY EARLY WEDNESDAY...WITH 
ADDITIONAL CLOUDINESS EXPECTED BY THURSDAY AS A WEAKENING COLD 
FRONT MOVES INTO THE REGION. TEMPERATURES WILL COOL BACK TO SEASONAL 
NORMS BY MID WEEK...THEN TURN SLIGHTLY WARMER FOR NEXT FRIDAY WITH 
HIGH PRESSURE AND SOME OFFSHORE FLOW DEVELOPING.

&&

.SHORT TERM (TODAY-MON)...OVERALL...00Z MODELS IN GOOD SYNOPTIC 
AGREEMENT THROUGH THE PERIOD. AT UPPER LEVELS...A FLAT RIDGE WILL 
SETTLE OVER THE AREA. NEAR THE SURFACE...OFFSHORE FLOW WILL CONTINUE 
TO WEAKEN THROUGH TODAY...THEN WEAK ONSHORE FLOW WILL REESTABLISH ON 
SUNDAY/MONDAY.

FORECAST-WISE...MAIN CONCERN WILL CONTINUE TO THE BE THE OFFSHORE 
WINDS. LATEST GRADIENT OBSERVATIONS STILL INDICATE STRONG OFFSHORE 
GRADIENTS (LAX-DAG STILL -6.0 MB) EARLY THIS MORNING. HOWEVER...SOME
ONSHORE TRENDS WILL BEGIN TO DEVELOP BY AFTERNOON. DESPITE WANING
UPPER LEVEL SUPPORT...STILL GETTING WIND GUSTS 40-50 MPH ACROSS THE 
MOUNTAINS...AND 25-40 MPH ACROSS THE VALLEYS. WILL ANTICIPATE A 
SLIGHT INCREASE IN WINDS AROUND SUNRISE...BUT THEN A GRADUAL 
WEAKENING THROUGH THIS AFTERNOON. GIVEN THE CURRENT WIND OBS...WILL
KEEP ADVISORIES IN PLACE FOR THE VENTURA/LOS ANGELES MOUNTAINS AND 
THE SANTA CLARITA VALLEY. FOR TONIGHT/SUNDAY...THERE WILL BE SOME 
LINGERING OFFSHORE WINDS...BUT NOTICEABLY WEAKER THAN THIS MORNING. 
BY MONDAY...THE WINDS WILL TURN WEAKLY ONSHORE.

OTHER THAN THE WINDS...SECONDARY CONCERN WILL BE TEMPS. WITH THE 
CONTINUED OFFSHORE FLOW TODAY...TEMPS WILL BE WELL ABOVE SEASONAL 
NORMS WITH MOST COASTAL/VALLEY AREAS IN THE 80S TO AROUND 90. ON 
SUNDAY...WILL EXPECT COASTAL/VALLEY TEMPS TO COOL SLIGHT...BUT 
INLAND AREAS TO WARM A BIT DUE TO THE WEAKER OFFSHORE FLOW. BY 
MONDAY...ALL AREAS WILL EXHIBIT SOME DEGREE OF COOLING WITH THE 
COASTAL AREAS EXPERIENCING THE BEST COOLING. 

THROUGH THE SHORT TERM PERIOD...SKIES SHOULD REMAIN MOSTLY CLEAR. 
OVERALL...JUST A VERY NICE WEEKEND ON TAP FOR THE AREA.

.LONG TERM (TUE-FRI)...OVERALL...THE 00Z MODELS CONTINUE TO BE IN 
DECENT SYNOPTIC AGREEMENT THROUGH THE PERIOD. AT UPPER LEVELS...
MAIN FEATURE TO WATCH WILL BE LOW THAT DEVELOPS OFF THE PACIFIC 
NORTHWEST EARLY NEXT WEEK AND MOVES EASTWARD...AND FINALLY INLAND
BY THURSDAY. NEAR THE SURFACE...ONSHORE FLOW WILL BE ON THE INCREASE 
THROUGH THE PERIOD.

FORECAST-WISE...THE ABOVE PATTERN WILL RESULT IN A CONTINUED COOLING
TREND THROUGH THURSDAY/FRIDAY...WITH AN INCREASING INFLUENCE OF 
MARINE LAYER STRATUS. THE TAIL END OF A FRONT IS FORECAST TO SWEEP 
ACROSS THE AREA THURSDAY/THURSDAY NIGHT. AT THIS TIME...THE GFS 
HOLDS THE FRONT TOGETHER BETTER THAN THE ECMWF...BUT EITHER SOLUTION 
APPEARS TO WEAKEN THE FRONT DRAMATICALLY WHEN IT APPROACHES NORTHERN 
SECTIONS OF THE CWA. GIVEN THIS WEAKENING TREND AS THE FRONT 
APPROACHES...HAVE KEPT POPS BELOW 15% AT THIS TIME. HOWEVER...WOULD 
NOT BE SHOCKED TO SEE SOME LOW GRADE MENTIONABLE POPS ADDED BY 
FUTURE SHIFTS FOR SLO/SBA COUNTIES. 

&&

.AVIATION...27/1145Z...

WILL BE UPDATED WITH THE 12Z TAF PACKAGE. 

&&

.FIRE...
BASED ON THE CURRENT OBSERVATIONS...WIDESPREAD CRITICAL FIRE WEATHER 
ARE CONTINUING THIS MORNING ACROSS VENTURA AND LOS ANGELES COUNTIES. 
MANY STATIONS ACROSS THE MOUNTAINS AND VALLEYS HAVE REPORTED 
EXTENDED DURATIONS OF SINGLE DIGIT RELATIVE HUMIDITY LAST EVENING 
AND THIS MORNING ALONG WITH WINDS GUSTING ANYWHERE BETWEEN 25 AND 
50 MPH. EXPECT THESE CRITICAL FIRE WEATHER CONDITIONS TO CONTINUE 
THROUGH THE MORNING AND EARLY AFTERNOON HOURS. THEREFORE...THE 
CURRENT RED FLAG WARNINGS ARE VERIFYING VERY NICELY AND WILL REMAIN 
IN PLACE THROUGH 600 PM THIS EVENING. 

&&

.LOX WATCHES/WARNINGS/ADVISORIES...
RED FLAG WARNING (SEE LAXRFWLOX).
WIND ADVISORY (SEE LAXNPWLOX).
SMALL CRAFT ADVISORY (SEE LAXMWWLOX).

&&

$$

PUBLIC...RAT
AVIATION...KAPLAN
FIRE...RAT
SYNOPSIS...SIRARD

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