High Wind Watch 1, NWS Los Angeles, CA

SOUTHWEST CALIFORNIA AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LOS ANGELES/OXNARD CA
120 PM PST SAT JAN 11 2014

.SYNOPSIS...

A TROUGH OF LOW PRESSURE WILL PASS THROUGH THE REGION THIS EVENING
BRINGING A PERIOD OF GUSTY NORTH WINDS TO PARTS OF THE AREA. HIGH
PRESSURE WILL BUILD INTO THE GREAT BASIN ON SUNDAY...RESULTING IN
GUSTY WINDS AND A WARMING TREND THROUGH THE MIDDLE OF NEXT WEEK.

&&

.SHORT TERM (TODAY-TUE)...HIGH CLOUDS WILL BE STREAMING THROUGH THE
AREA TONIGHT AS A STORM MOVES THROUGH THE PAC NW. BEHIND THAT SYSTEM
A STRONG NORTHERLY GRADIENT WILL SET UP, SIMILAR TO THURSDAY NIGHT
THOUGH NOT QUITE AS STRONG. THE RESULT WILL BE ANOTHER ROUND OF
ADVISORY LEVEL NORTHERLY WINDS ACROSS SRN SBA COUNTY AND THE I5
CORRIDOR TONIGHT THROUGH EARLY SUNDAY. SOME OF THESE WINDS WILL
FILTER DOWN INTO THE VENTURA/LA VALLEYS AND SANTA MONICAS THOUGH
BELOW ADVISORY LEVELS. DRY AND A LITTLE WARMER MOST AREAS SUNDAY.

GRADIENTS WILL QUICKLY SHIFT TO NORTHEAST SUNDAY NIGHT AS A STRONG
SANTA ANA WIND EVENT DEVELOPS. MODELS SHOWING GOOD COLD AIR
ADVECTION WITH THIS EVENT WHICH WILL ASSIST THE WINDS, BUT ALSO MAKE
FOR A SOMEWHAT TRICKY TEMPERATURE FORECAST. LOCAL HISTORICAL STUDIES
SUGGEST A SOMEWHAT COOLER HIGH TEMPERATURE FORECAST MON/TUE THAN
WHAT MOS GUIDANCE AND CURRENT FORECAST SHOWS. GIVEN THICKNESSES
AROUND 560 AND 12Z 950 TEMPS ONLY AROUND 16C A SLIGHTLY COOLER
FORECAST SEEMS REASONABLE. LOOKING BACK AT SEVERAL STRONG OFFSHORE
PATTERNS WHERE LAX-DAG GRADIENT WAS IN EXCESS OF -7MB IT WAS RARE TO
GET TEMPS WARMER THAN LOW TO MID 70S IN THE VALLEYS. SO I'VE LOWERED
THE HIGHS A FEW DEGREES MOST AREAS, BUT ESPECIALLY THE VALLEYS.
COASTAL AREAS MON/TUE WILL BE THE WARMEST AND HAVE AN OUTSIDE SHOT
AT 80 DEGREES, BUT MID TO HIGH 70S A BETTER BET. EITHER WAY, STILL
5-10 DEGREES ABOVE NORMAL MOST AREAS.

WILL BE ISSUING A HIGH WIND WATCH FOR THE LA/VENTURA MTNS SUN NT
THRU TUE AFTN. THE GRADIENTS AND COLD ADVECTION SHOULD BE MORE THAN
ENOUGH TO GENERATE WARNING LEVEL GUSTS IN THE FAVORED MTN AREAS
SURROUNDING THE HIGHWAY 14 CORRIDOR AND IN THE SANTA MONICAS. A GOOD
SOLID ADVISORY EVENT FOR THE REMAINDER OF VENTURA/LA COUNTIES,
THOUGH AS USUAL GENERALLY LIGHT WINDS FOR LA COASTAL ZONE OUTSIDE
THE MALIBU TO HOLLYWOOD HILLS AREAS.

VERY LITTLE CHANGE IN THE SCENARIO TUESDAY AS GRADIENTS AND WINDS
ALOFT REMAIN AT MONDAY'S LEVELS. PROBABLY A BIT WARMER TUE, MOSTLY
DUE TO A WARMER START, BUT DECENT COLD ADVECTION STILL CONTINUES SO
TEMPS WILL BE STRUGGLING TO WARM UP TOO MUCH ACROSS THE INTERIOR
DESPITE THE STRONG LOW LVL SUBSIDENCE.

RECORD HIGHS FOR LOWER ELEVATIONS MON/TUE GENERALLY IN THE MID 80S
SO IT DOESN'T LOOK LIKE WE'LL GET THERE UNLESS THE COLD ADVECTION
ENDS UP NOT BEING AS STRONG AS ADVERTISED.

.LONG TERM (WED-SAT)...WINDS EXPECTED TO BE DECREASING TUESDAY NIGHT
INTO WEDNESDAY, THOUGH STILL SOME GUSTY WINDS EXPECTED. MOSTLY
GRADIENT DRIVEN AT THAT POINT AS WE LOSE SUPPORT ALOFT. HIGHS SHOULD
BE WARMING UP AS WELL WITH THE RIDGE PEAKING ALOFT, THE WARMEST OF
THE WEEK IN FACT, ESPECIALLY FOR INTERIOR AREAS THAT WERE HELD BACK
THE PREVIOUS COUPLE DAYS WITH THE COLD ADVECTION. OFFSHORE GRADIENTS
EXPECTED THROUGH FRIDAY, THOUGH A LITTLE WEAKER EACH DAY. THU HIGHS
PROBABLY A TOUCH COOLER THEN SIMILAR TRENDS FRIDAY. STILL WELL ABOVE
NORMAL, AND VERY DRY. THE RIDGE IS EXPECTED TO START BREAKING DOWN
FRIDAY INTO SATURDAY. AT THAT POINT MODELS START TO DIVERGE WITH THE
GFS MORE PROGRESSIVE WITH THE WEEKEND TROF AND STILL DRY WHILE THE
ECMWF PINCHES OFF A CUTOFF LOW BY AROUND NEXT SUNDAY WITH A SMALL
THREAT OF SOME LIGHT PRECIP, THOUGH MAINLY TO OUR SOUTH.

&&

.AVIATION...11/1800Z...MODERATE TO HIGH CONFIDENCE IN 18Z TAFS. VFR
CONDS EXPECTED THROUGHOUT THE AREA EXCEPT FOR A 20% CHANCE OF LOW
CLOUDS/FG OVER KLGB SUNDAY MORNING. GUSTY N WINDS ARE EXPECTED TO
DEVELOP IN THE MTNS TONIGHT...WITH STRONGER WINDS ALOFT SPREADING
OVER THE VLYS OF L.A. COUNTY AND THE S COAST OF SBA
COUNTY...PRODUCING LLWS AND MDT UDDF.

KLAX...MODERATE TO HIGH CONFIDENCE IN THE 18Z TAF. VFR CONDS
EXPECTED BUT THERE IS A 10% CHANCE OF LOW CIGS/VSBY DURING THE
MORNING HOURS SUNDAY. LLWS EXPECTED BETWEEN 12Z-17Z BUT 20% CHANCE
WINDS ALOFT WILL NOT AFFECT THE AIRFIELD.

KBUR...HIGH CONFIDENCE IN THE 18Z TAF WITH VFR CONDITIONS EXPECTED
THRU THE PERIOD AND LLWS BETWEEN 11Z-17Z SUNDAY.

&&

.FIRE WEATHER...11/1830Z...
GUSTY NORTH WINDS WILL ONCE AGAIN DEVELOP OVERNIGHT INTO SUNDAY
MORNING ACROSS THE SANTA YNEZ RANGE...SANTA BARBARA SOUTH
COAST...AND INTERSTATE 5 CORRIDOR OF THE LOS ANGELES COUNTY
MOUNTAINS...WHERE GUSTS OF 40 TO 50 MPH WILL BE COMMON. HUMIDITY
LEVELS ARE GENERALLY EXPECTED TO REMAIN IN THE 20 TO 30 PERCENT
RANGE ACROSS DOWNSLOPE AREAS...WITH HIGHER HUMIDITIES ACROSS THE
NORTH FACING SLOPES. WINDS WILL GRADUALLY SHIFT TO THE NORTHEAST AND
WEAKEN SLIGHTLY ACROSS MUCH OF THE FORECAST AREA ON SUNDAY...BRINGING
A WARMING AND DRYING TREND.

STRONG SURFACE HIGH PRESSURE WILL THEN BUILD ACROSS THE GREAT BASIN
SUNDAY NIGHT THROUGH TUESDAY...BRINGING INCREASED OFFSHORE FLOW
ACROSS SOUTHERN CALIFORNIA. DURING THIS TIME...THERE WILL BE
MODERATE TO STRONG SANTA ANA WINDS IMPACTING TYPICAL WIND PRONE
LOCATIONS OF LOS ANGELES AND VENTURA COUNTIES. OFFSHORE WINDS ARE
EXPECTED TO INCREASE SHARPLY BY MIDNIGHT ON SUNDAY NIGHT ACROSS THE
MOUNTAINS...SPREADING INTO THE VALLEYS AND COASTAL AREAS OVERNIGHT
INTO EARLY MONDAY MORNING. LAX-DAGGETT GRADIENT EXPECTED TO PEAK IN
THE -7 TO -7.5 MB RANGE ON BOTH MONDAY MORNING AND TUESDAY MORNING.
PEAK WIND GUSTS ON MONDAY AND TUESDAY ACROSS THE MOUNTAINS WILL
GENERALLY RANGE BETWEEN 50 AND 60 MPH...WHILE COASTAL AND VALLEY
AREAS CAN EXPECT GUSTS IN THE 40 TO 50 MPH RANGE. HUMIDITIES WILL
LIKELY LOWER INTO THE TEENS ACROSS MUCH OF LOS ANGELES AND VENTURA
COUNTIES LATE SUNDAY NIGHT INTO MONDAY MORNING...FALLING TO AROUND 10
PERCENT BY MONDAY AFTERNOON. WIDESPREAD SINGLE DIGIT HUMIDITIES CAN
THEN BE EXPECTED BY LATE MONDAY NIGHT INTO TUESDAY AS EVEN DRIER AIR
FILTERS INTO THE AREA.

THE COMBINATION OF MODERATE TO STRONG SANTA ANA WINDS...WARM
TEMPERATURES...LOW HUMIDITIES...AND VERY DRY FUELS WILL BRING THE
POTENTIAL FOR A PROLONGED PERIOD OF CRITICAL FIRE WEATHER CONDITIONS
TO A LARGE PORTION OF SOUTHERN CALIFORNIA. FIRE WEATHER WATCHES WILL
BE UPGRADED TO RED FLAG WARNINGS WITH THE AFTERNOON FORECAST
ISSUANCE. GUSTY OFFSHORE WINDS ARE ALSO EXPECTED TO CONTINUE INTO
WEDNESDAY...ALTHOUGH WIND SPEEDS ARE NOT EXPECTED TO BE AS STRONG AS
MONDAY AND TUESDAY. THESE OFFSHORE WINDS COMBINED WITH SINGLE DIGIT
HUMIDITIES MAY REQUIRE THE EXTENSION OF CRITICAL FIRE WEATHER
CONDITIONS INTO WEDNESDAY AFTERNOON. WEAKER OFFSHORE FLOW WILL
MAINTAIN WARM TEMPERATURES AND SINGLE DIGIT HUMIDITIES INTO THURSDAY
AND FRIDAY.

&&

.LOX WATCHES/WARNINGS/ADVISORIES...
RED FLAG WARNING (SEE LAXRFWLOX).
HIGH WIND WATCH (SEE LAXNPWLOX).
WIND ADVISORY (SEE LAXNPWLOX).
SMALL CRAFT ADVISORY (SEE LAXMWWLOX).
HIGH SURF ADVISORY (SEE LAXCFWLOX).
HIGH RIP CURRENT RISK (SEE LAXSRFLOX).

&&

PUBLIC...MW
AVIATION...SMITH
SYNOPSIS...SUKUP

WWW.WEATHER.GOV/LOSANGELES

HAZARDOUS WEATHER OUTLOOK...UPDATED
NATIONAL WEATHER SERVICE LOS ANGELES/OXNARD CA
927 AM PST SAT JAN 11 2014

CAZ034>041-044>046-051>054-059-087-088-547-548-121400-
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-
927 AM PST SAT JAN 11 2014

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

THERE WILL BE GUSTY NORTHERLY WINDS THIS EVENING ACROSS SOUTHERN
SANTA BARBARA COUNTY AND THE INTERSTATE 5 CORRIDOR.

* WIND ADVISORY..............SEE WWUS76 KLOX - NPWLOX FOR DETAILS *

* HIGH RIP CURRENT RISK......SEE FZUS56 KLOX - SRFLOX FOR DETAILS *

.DAYS TWO THROUGH SEVEN... SUNDAY THROUGH FRIDAY

SURF OF 12 TO 15 FEET WITH LOCAL SETS TO 20 FEET ARE EXPECTED FOR
THE CENTRAL COAST. SURF SHOULD SUBSIDE SOME MONDAY NIGHT INTO
TUESDAY. A STRONG SANTA ANA EVENT IS EXPECTED LATE SUNDAY EVENING
INTO MONDAY AFFECTING THE USUAL WIND PRONE LOCATIONS OF LOS ANGELES
AND VENTURA COUNTIES. THERE WILL BE THE POTENTIAL FOR RAPID FIRE
GROWTH AS RELATIVE HUMIDITY LEVELS ARE EXPECTED TO LOWER DOWN TO
SINGLE DIGITS BY MONDAY AND PERSIST THROUGH WEDNESDAY.

* FIRE WEATHER WATCH.........SEE WWUS86 KLOX - RFWLOX FOR DETAILS *

* WIND ADVISORY..............SEE WWUS76 KLOX - NPWLOX FOR DETAILS *

* HIGH SURF ADVISORY.........SEE WHUS46 KLOX - CFWLOX FOR DETAILS *

* HIGH RIP CURRENT RISK......SEE FZUS56 KLOX - SRFLOX FOR DETAILS *

.SPOTTER INFORMATION STATEMENT...

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

MW