High Wind Watch 8, NWS Los Angeles, CA

SOUTHWEST CALIFORNIA AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LOS ANGELES/OXNARD CA
1001 AM PST FRI DEC 27 2013

.SYNOPSIS...

HIGH PRESSURE WILL BRING ABOVE NORMAL TEMPERATURES TO
SOUTHWESTERN CALIFORNIA TODAY...ALONG WITH LINGERING GUSTY
OFFSHORE WINDS IN SOME AREAS THROUGH MID MORNING. A DRY AND FAST
MOVING LOW PRESSURE SYSTEM WILL BRING INCREASING CLOUDS AND
SLIGHTLY COOLER TEMPERATURES TO THE AREA ON SATURDAY. A WARMING
TREND IS EXPECTED SUNDAY INTO EARLY NEXT WEEK AS HIGH PRESSURE
REBUILDS INTO THE EASTERN PACIFIC.

&&

.UPDATE...

WATER VAPOR IMAGERY OVER THE REGION INDICATES RIDGING ALOFT
SLOWLY MOVING EAST THIS MORNING. THE RIDGE AXIS...REMAINING OVER
SOUTHERN CALIFORNIA...WILL ALLOW FOR ANOTHER WARM DAY BEFORE
SLIDING EAST OF THE REGION THIS EVENING. NEAR RECORD HIGH TEMP
HEADLINES WERE ADDED TO THE PACKAGE FOR TODAY FOR THE SOUTHERN
COASTS AND VALLEYS AS THE WARMEST TEMPERATURES TODAY WILL LIKELY
OCCUR ACROSS LOS ANGELES AND VENTURA COUNTY COAST...VALLEYS...AND
FOOTHILLS. SEVERAL LOCATIONS ACROSS LOS ANGELES COUNTY WERE
ALREADY WARMING QUICKLY THIS MORNING...AND SEVERAL DEGREES OVER
THIS TIME YESTERDAY. WITH THE RIDGE SLIDING EAST...A COOLING
TREND IS ON TAP FOR THE WEEKEND AS A WEAK TROUGH APPROACHES.

HIGH LEVEL CLOUDINESS STREAMING INTO THE RIDGE TODAY WILL
INCREASE AS THE WEAK TROUGH APPROACHES. INFRARED AND WATER VAPOR
SATELLITE IMAGERY SUGGEST A DENSE CIRRUS CLOUD SHIELD ON TAP FOR
TONIGHT...AGREEING WELL WITH THE GFS 300 AND 400 MB RELATIVE
HUMIDITY VALUES. THE HIGH CLOUDINESS WILL DEFINITELY MAKE MINIMUM
TEMPERATURES WARMER AND MAKE FROST MORE PATCHY ACROSS THE INTERIOR
VALLEYS TONIGHT...BUT IT MAY ALSO CUT INTO HIGH TEMPERATURES TODAY
ACROSS SAN LUIS OBISPO AND NORTHERN SANTA BARBARA COUNTY. WITH
INCREASING ONSHORE FLOW EXPECTED TODAY...AND THE HIGH LEVEL
MOISTURE TEMPERATURES WERE COOLED SLIGHTLY ALONG THE CENTRAL COAST
BEACHES TODAY.

A COOLER DAY LOOKS ON TAP FOR SATURDAY AS THE TROUGH DROPS INTO
THE REGION. MAIN CONCERN FOR THE SHORT-TERM PORTION IS
DEVELOPMENT OF THE POSSIBILITY OF STRONG SANTA ANA WINDS BETWEEN
SATURDAY NIGHT AND SUNDAY NIGHT. GFS MODEL TRENDS SEEM CONFIDENT
IN THE UPPER-LEVEL PATTERN AND NAM-WRF SOLUTIONS ARE SUGGESTING
THE POTENTIAL FOR DAMAGING WIND GUSTS IN THE MOUNTAINS OF LOS
ANGELES AND VENTURA COUNTIES. WHILE CONFIDENCE IS MODERATE AT
THIS TIME...CONFIDENCE IS GROWING FOR A POSSIBLE STRONG WIND
EVENT DEVELOPING BETWEEN SATURDAY NIGHT AND SUNDAY NIGHT. FIRE
WEATHER CONDITIONS...CRITICAL THE LAST SEVERAL DAYS...COULD
BECOME CRITICAL ONCE AGAIN BETWEEN SATURDAY NIGHT AND SUNDAY
NIGHT.

&&

.PREV DISCUSSION...

LONG TERM (SUN-WED)...WEAK RIDGING AND OFFSHORE FLOW WILL CONTINUE
INTO THE NEW YEAR. WINDS SHOULD REMAIN BLO ADVISORY LEVELS. MAX
TEMPS WILL REMAIN WELL ABOVE NORMAL. RAIN CHC IS ZERO. CLOUDS WILL
BE FAR AND FEW BETWEEN. FIRE DANGER WILL REMAIN ELEVATED.

&&

.AVIATION...27/1800Z.

MID/UPPER LEVEL TROUGH OF LOW PRESSURE UPSTREAM WILL MOVE OVER THE
AREA. UPPER LEVEL MODERATE WEST WINDS WILL BECOME MODERATE NORTH
AFTER 28/18Z WHILE MID LIGHT EAST WINDS BECOME VARIABLE BETWEEN
28/00-28/06Z THEN LIGHT NORTHWEST. INCREASING UPPER LEVEL MOISTURE
AFTER 28/04Z THEN DECREASING AFTER 28/19Z. FREEZING LEVEL WAS
APPROXIMATELY 11.5KFT OVER THE AREA THIS MORNING AND LITTLE CHANGE
IS EXPECTED. MIXED WEAK ONSHORE AND OFFSHORE PRESSURE GRADIENT
THROUGH 28/02Z AND AFTER 28/20Z OTHERWISE WEAK OFFSHORE
GRADIENT.

KLAX...VIRTUALLY CERTAIN CURRENT SKY/VSBY CONDITIONS WILL PERSIST
THROUGH 28/11Z THEN 200 OVC BETWEEN 28/11-28/19Z.

KBUR...VIRTUALLY CERTAIN CURRENT SKY/VSBY CONDITIONS WILL PERSIST
THROUGH 28/11Z THEN 200 OVC.

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

&&

.FIRE WEATHER...27/1730Z.

LIGHT OFFSHORE BREEZES CONTINUE TO REINFORCE A VERY WARM AND DRY
AIR MASS ACROSS SOUTHERN CALIFORNIA THIS MORNING. WIND SPEEDS
WILL CONTINUE TO DIMINISH THROUGH THE DAY...ALLOWING FOR THE
EXPIRATION OF THE RED FLAG WARNING. HOWEVER...WIDESPREAD SINGLE
DIGIT HUMIDITIES AND VERY DRY FUELS WILL CONTINUE TO BRING
ELEVATED FIRE DANGER TODAY. POOR HUMIDITY RECOVERIES EXPECTED
ONCE AGAIN TONIGHT IN THE MOUNTAINS AND FOOTHILLS...FOLLOWED BY
HUMIDITIES IN THE TEENS AND SINGLE DIGITS ACROSS MOST INLAND
AREAS ON SATURDAY.

SURFACE HIGH PRESSURE WILL BEGIN TO REBUILD ACROSS THE GREAT
BASIN SATURDAY NIGHT...SETTING THE STAGE FOR ANOTHER SANTA ANA
WIND EVENT ACROSS SOUTHERN CALIFORNIA. THERE ARE NOW INDICATIONS
THAT THIS UPCOMING OFFSHORE WIND EVENT WILL BE STRONGER THAN
PREVIOUSLY EXPECTED. LAX-DAGGETT GRADIENT COULD POTENTIALLY PEAK
AT -7 MB OFFSHORE ON SUNDAY MORNING...WITH BETTER UPPER LEVEL
WIND SUPPORT THAN THIS PREVIOUS OFFSHORE EVENT. PEAK OFFSHORE
WINDS ARE EXPECTED TO OCCUR LATE SATURDAY NIGHT THROUGH SUNDAY
AFTERNOON...WHEN THERE WILL BE THE POTENTIAL FOR WIND GUSTS IN
THE 50 TO 60 MPH RANGE ACROSS THE MOUNTAINS...AND 40 TO 50 MPH
ACROSS LOWER ELEVATIONS. MEANWHILE...HUMIDITIES WILL LIKELY FALL
INTO THE TEENS AND SINGLE DIGITS ON SUNDAY DURING THIS EVENT. IF
THE COMPUTER MODELS CONTINUE TO TREND TOWARDS THIS STRONGER
OFFSHORE WIND EVENT...A FIRE WEATHER WATCH MAY BE ISSUED WITH THE
AFTERNOON FORECAST FOR PORTIONS OF LOS ANGELES AND VENTURA
COUNTIES. OFFSHORE BREEZES AND LOW HUMIDITIES ARE ALSO EXPECTED
TO BRING ELEVATED FIRE DANGER TO SAN LUIS OBISPO AND SANTA
BARBARA COUNTIES LATE SATURDAY NIGHT INTO SUNDAY. WHILE OFFSHORE
WINDS ARE EXPECTED TO WEAKEN ON SUNDAY NIGHT AND MONDAY...A WARM
AND VERY DRY AIR MASS WILL REMAIN WITH THE POTENTIAL FOR
WIDESPREAD SINGLE DIGIT HUMIDITIES DURING THIS TIME.

&&

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

&&

PUBLIC...HALL
AVIATION...30
FIRE WEATHER...GOMBERG
SYNOPSIS...SWEET/HALL

WWW.WEATHER.GOV/LOSANGELES

HAZARDOUS WEATHER OUTLOOK...UPDATED
NATIONAL WEATHER SERVICE LOS ANGELES/OXNARD CA
1031 AM PST FRI DEC 27 2013

CAZ034>041-044>046-051>054-059-087-088-547-548-281400-
SAN LUIS OBISPO COUNTY CENTRAL COAST-
SANTA BARBARA COUNTY CENTRAL COAST-SANTA YNEZ VALLEY-
SAN LUIS OBISPO COUNTY INTERIOR VALLEYS-CUYAMA VALLEY-
SANTA BARBARA COUNTY SOUTH COAST-VENTURA COUNTY COAST-
LOS ANGELES COUNTY COAST INCLUDING DOWNTOWN LOS ANGELES-
VENTURA COUNTY INTERIOR VALLEYS-VENTURA COUNTY COASTAL VALLEYS-
SANTA MONICA MOUNTAINS RECREATIONAL AREA-
SAN LUIS OBISPO COUNTY MOUNTAINS-
SANTA BARBARA COUNTY MOUNTAINS-VENTURA COUNTY MOUNTAINS-
LOS ANGELES COUNTY MOUNTAINS EXCLUDING THE SANTA MONICA RANGE-
ANTELOPE VALLEY-CATALINA ISLAND-SANTA CLARITA VALLEY-
LOS ANGELES COUNTY SAN FERNANDO VALLEY-
LOS ANGELES COUNTY SAN GABRIEL VALLEY-
1031 AM PST FRI DEC 27 2013

THIS HAZARDOUS WEATHER OUTLOOK IS FOR SOUTHWESTERN CALIFORNIA.

WFO LOX PLANS TO DISCONTINUE THIS PRODUCT IN 2014.
PLEASE DIRECT ANY COMMENTS TO ERIC BOLDT AT 805-988-6623.

.DAY ONE... TODAY AND TONIGHT

NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.

.DAYS TWO THROUGH SEVEN... SATURDAY THROUGH THURSDAY

THERE IS POSSIBILITY OF STRONG SANTA ANA WINDS DEVELOPING LOS
ANGELES AND VENTURA COUNTIES BETWEEN SATURDAY NIGHT AND SUNDAY
NIGHT.

.SPOTTER INFORMATION STATEMENT...

WEATHER SPOTTERS ARE ENCOURAGED TO REPORT SIGNIFICANT WEATHER
CONDITIONS ACCORDING TO STANDARD OPERATING PROCEDURES.

HALL