Small Craft Advisory 119, NWS Los Angeles, CA

SOUTHWEST CALIFORNIA AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE LOS ANGELES/OXNARD CA
200 PM PDT SAT NOV 3 2012

...UPDATED PUBLIC DISCUSSION...

.SYNOPSIS...
SURFACE HIGH PRESSURE WILL BUILD INTO THE GREAT BASIN THIS
WEEKEND...RESULTING IN WEAK OFFSHORE FLOW...CLEAR SKIES...AND ABOVE
NORMAL TEMPERATURES THROUGH TUESDAY. A COOLING TREND IS THEN
EXPECTED THROUGH THE END OF NEXT WEEK AS A TROUGH OF LOW PRESSURE
DROPS IN FROM THE NORTH. WELL BELOW NORMAL TEMPERATURES AND RAIN ARE
POSSIBLE LATE IN THE WEEK.

&&

.SHORT TERM (TODAY-WED)...
WINDS HAVE TURNED FROM ONSHORE TO OFFSHORE IN MOST OF THE CWA AND
THIS IS HELPING TO KEEP SKIES CLEAR AND THE MARINE LAYER WELL OFF
THE COAST.  TEMPERATURES WILL END THE DAY WARMER... WITH MOST
COASTAL AREAS QUITE A BIT WARMER DUE TO THE LACK OF MORNING CLOUD
COVER.

THE HIGH PRESSURE RIDGE HAS BEEN BUILDING MORE SHARPLY OVER THE
SOUTHWEST AND THIS WILL RESULT IN A STRONGER SURFACE WIND GRADIENT
FROM THE INLAND EMPIRE INTO THE LOS ANGELES METRO AREA THAN WAS
PROJECTED YESTERDAY.  THE STRENGTH OF THE WINDS WAS BUMPED UP IN THE
FORECAST UPDATE BUT THEY REMAIN BELOW WIND ADVISORY CRITERIA AND THE
TIMING OF THE STRONGEST WINDS CONTINUES TO BE FROM LATE SUNDAY
OVERNIGHT INTO MONDAY.  TEMPERATURES WILL BE TEN TO FIFTEEN DEGREES
ABOVE NORMAL FOR MANY LOCATIONS BY MONDAY AFTERNOON.  THE RIDGE
FLATTENS RATHER QUICKLY HOWEVER AND BY LATE ON TUESDAY THE REGION
WILL BE RETURNING TO A WEAK ONSHORE FLOW AND TEMPERATURES WILL BE
COOLING AGAIN.  WEDNESDAY WILL BE A MILD DAY WITH SOME LOCALLY DENSE
FOG AND LOW CLOUDS ALONG THE COAST AND MODERATE TEMPERATURES AND
WINDS IN GENERAL.

.LONG TERM (WED-SAT)...
THE NEXT WEATHER EVENT FOR THE REGION IS FORECAST TO BEGIN ON
THURSDAY IN THE NORTHERN COUNTIES BUT THE TIMING REMAINS A LITTLE
UNCERTAIN.  IT COULD COME LATE WEDNESDAY NIGHT BUT MORE LIKELY IF IT
MISSES THE THURSDAY MARK IT WILL BE LATE AND COME EARLY FRIDAY.
PART OF THE UNCERTAINTY REGARDS THE TIMING IS THAT THERE IS STILL
SOME UNCERTAINTY AS TO HOW FAR SOUTH THE LOW CENTER WILL DROP AND
HOW FAST IT WILL MOVE THROUGH.  THIS WILL ALSO MAKE A DIFFERENCE ON
HOW MUCH PRECIPITATION WILL COME TO THE AREA AS A SLOWER MOVING
SYSTEM WILL HAVE MORE TIME TO PRECIPITATE OVER THE REGION.  CURRENT
PROJECTIONS ARE THAT THE SYSTEM WILL LINGER INTO THE WEEKEND AND
BRING LIGHT TO MODERATE RAIN TO MOST OF SOUTHERN CALIFORNIA OFF AND
ON.  AS THE LOW MOVES SOUTH IT WILL ALSO BRING SOME OF THE COLDEST
TEMPERATURES OF THE SEASON THUS FAR ALONG WITH IT.

STORM PRECIP TOTAL WILL NOT BE HIGH BUT THE MULTI-DAY PRECIPITATION
CHANCES AND COLDER TEMPERATURES WILL MAKE THIS FEEL LIKE A WINTER
SEASON STORM.

&&

.AVIATION...03/1800Z.

MID/UPPER LEVEL RIDGE OF HIGH PRESSURE CENTERED OVER THE EASTERN PAC
AND EXTENDING OVER NORTHERN CALIFORNIA WILL CONTINUE TO STRENGTHEN.
UPPER LEVEL MODERATE NORTH WINDS WILL BECOME MODERATE EAST AFTER
04/18Z WHILE MID LEVEL LIGHT EAST WINDS BECOME LIGHT TO MODERATE
AFTER 04/10Z. MARINE INVERSION WITH AN ISOLATED CLOUD FIELD WITH
TOPS 1KFT THIS MORNING WILL CONTINUE TO STRENGTHEN AND DESCEND AND
DIFFER BY MINUS 1KFT SUNDAY MORNING. MIXED WEAK ONSHORE AND
NORTHERLY PRESSURE GRADIENT THROUGH 04/02Z...THEN WEAK TO MODERATE
NORTHEASTERLY GRADIENT BETWEEN 04/06-04/18Z AND MIXED WEAK ONSHORE
AND OFFSHORE GRADIENT AFTER 04/18Z.

KLAX...CHANCE 5SM THROUGH 03/19Z AND BETWEEN 04/16-04/19Z. LOW LEVEL
EAST WINDS BETWEEN 04/06-04/19Z AND VERY LIKELY LESS THAN 10KT.

KBUR...LIKELY CURRENT SKY/VSBY CONDITIONS WILL PERSIST.

VIRTUALLY CERTAIN - 95-100%
VERY LIKELY       - 80-95%
LIKELY            - 60-80%
CHANCE            - 30-60%
VERY UNLIKELY     - 20% OR LESS

.FIRE WEATHER...
ELEVATED FIRE DANGER ACROSS THE REGION SUNDAY INTO MONDAY AS BREEZY
OFFSHORE WINDS BRING WARMER AND DRIER CONDITIONS. OFFSHORE WINDS
WILL BEGIN TO OVERSPREAD THE REGION LATE TONIGHT INTO SUNDAY...THEN
PEAK SUNDAY NIGHT INTO MONDAY.  WHILE OFFSHORE WINDS DO NOT LOOK AS
STRONG OR WIDESPREAD AS WHAT OCCURRED LAST WEEK...THERE WILL BE THE
POTENTIAL FOR CRITICAL FIRE WEATHER CONDITIONS ACROSS WIND PRONE
LOCATIONS SUNDAY NIGHT INTO MONDAY...ESPECIALLY SINCE FUELS REMAIN
CRITICALLY DRY. LATEST NAM-12 MODEL STILL INDICATES LAX-DAGGETT
GRADIENT TO BE AROUND -2.5 MB ON SUNDAY MORNING AND -3.5 MB ON
MONDAY MORNING...WHICH IS ON THE LOW SIDE FOR OFFSHORE EVENTS.
HOWEVER...THE UPPER LEVEL WIND SUPPORT AT 850 MB IS SLIGHTLY
STRONGER ON THIS MORNING'S RUN. IN ADDITION...CROSS SECTIONS SHOW
THE POTENTIAL FOR A PERIOD OF HUMIDITIES TO BE AROUND 10 PERCENT OR
LESS FROM SUNDAY NIGHT THROUGH MONDAY. THIS IS A MARGINAL OFFSHORE
WIND EVENT...BUT CONSIDERING THE STATUS OF THE VERY DRY AND CRITICAL
FUELS AND POTENTIAL FOR A LONG DURATION OF VERY LOW
HUMIDITIES...THERE WAS SUFFICIENT REASON TO ISSUE THIS FIRE WEATHER
WATCH. THERE WILL BE THE POTENTIAL FOR WIND GUSTS IN THE 30 TO 40
MPH RANGE ACROSS THE MOUNTAINS...AND 25 TO 35 MPH ACROSS THE SANTA
CLARITA VALLEY AND EASTERN VENTURA COUNTY VALLEYS. POOR HUMIDITY
RECOVERIES EXPECTED SUNDAY NIGHT AND MONDAY NIGHT ACROSS WIND EXPOSED
LOCATIONS AND FOOTHILLS. CONTINUED VERY WARM AND DRY ON
TUESDAY...HOWEVER OFFSHORE WINDS EXPECTED TO BE WEAKER AND NOT
EXPECTED TO REACH ANY RED FLAG THRESHOLDS.

&&

.LOX WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

PUBLIC...KJ
AVIATION...FORWOOD
FIRE...GOMBERG
SYNOPSIS...SUKUP

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