Area Forecast Discussion
Issued by NWS Los Angeles, CA

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000
FXUS66 KLOX 260507
AFDLOX

SOUTHWEST CALIFORNIA AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LOS ANGELES/OXNARD CA
905 PM PST THU DEC 25 2014

.SYNOPSIS...

HIGH PRESSURE BUILDING INTO THE GREAT BASIN WILL PRODUCE GUSTY NORTH
AND NORTHEAST WINDS FOR PARTS OF THE AREA THROUGH SATURDAY AND
MOSTLY CLEAR SKIES THROUGH THE WEEKEND. A LARGE LOW PRESSURE SYSTEM
MAY BRING UNSETTLED WEATHER TO THE REGION FOR THE EARLY AND MIDDLE
PART OF NEXT WEEK. TEMPERATURES WILL REMAIN SLIGHTLY BELOW NORMAL
THROUGH THE WEEKEND...WITH COOLER CONDITIONS POSSIBLE NEXT WEEK.

&&

.SHORT TERM (TODAY-SUN)...
MAIN CONCERN IN THE IMMEDIATE SHORT TERM CONTINUES TO BE THE WINDS.
THE NORTHERLY WINDS HAVE DIMINISHED IN STRENGTH THIS EVENING...BUT
STILL SOME DECENT GUSTS OUT THERE. OVERNIGHT INTO FRIDAY MORNING THE
WINDS WILL BEGIN TO SHIFT TO THE NORTHEAST AND SHOULD STRENGTHEN
AROUND SUNRISE. SO...WILL KEEP CURRENT WIND ADVISORIES IN EFFECT
THIS EVENING...KEEPING SPEEDS AT THE LOW END OF THE ADVISORY
SPECTRUM. OTHERWISE...SATELLITE SHOWS SOME CLOUDS LINGERING ACROSS
INTERIOR SECTIONS OF THE DISTRICT...AND THOSE CLOUDS COULD LINGER
INTO FRIDAY MORNING...WITH SUNNY SKIES PREVAILING THE BALANCE OF
FRIDAY.

FOR FRIDAY NIGHT AND SATURDAY...00Z MODELS CONTINUE TO INDICATE
STRONGER NORTHEAST WINDS DUE TO A STRONGER OFFSHORE GRADIENT AND
BETTER UPPER LEVEL/THERMAL SUPPORT. SO...ANOTHER ROUND OF ADVISORIES
WILL BE LIKELY...AND MAY NEED TO BE EXTENDED TO THE COASTAL PLAIN OF
VENTURA AND LOS ANGELES COUNTIES. ALSO...THE NORTHEAST WINDS COULD
HAVE SOME IMPACTS UPON THE EAST SIDE OF CATALINA ISLAND.

BY SATURDAY NIGHT/SUNDAY...THE OFFSHORE WINDS WILL DECREASE
SIGNIFICANTLY AND RATHER BENIGN WEATHER IS EXPECTED. THROUGHOUT THE
WEEKEND...THINGS WILL REMAIN ON THE COOL SIDE...WITH HIGH
TEMPERATURES HOVERING NEAR SEASONAL NORMS.

*** LONG TERM FROM PREVIOUS DISCUSSION ***

.LONG TERM (MON-THU)...BOTH THE GFS AND ECMWF ARE IN AGREEMENT THAT
A VERY COLD AND DYNAMIC UPPER LOW WILL BE RETROGRADING TOWARDS
SOUTHERN CALIFORNIA EARLY NEXT WEEK AND REMAIN OVER THE REGION INTO
AT LEAST WEDNESDAY. AT LEAST THAT IS WHAT THE LAST TWO MODEL RUNS
WERE ADVERTISING. RELUCTANTLY...IN COORDINATION WITH OUR NEIGHBORING
OFFICE HAVE ADDED SLIGHT CHANCE POPS TO THE FORECAST BEGINNING NEXT
TUE-WED. THE REASON I AM RELUCTANT ABOUT THIS...IS JUST 24 HOURS
AGO...THE UPPER LOW WAS SETTING UP JUST TO THE EAST OF THE FORECAST
AREA WHICH HAD THE POTENTIAL TO BRING A DAMAGING WIND EVENT TO
LA/VTU COUNTIES DUE TO GREAT UPPER LEVEL SUPPORT. SO THAT BEING
SAID...WOULD NOT BE SURPRISED IF MODELS TAKE THE UPPER LOW BACK TO
THE EAST WHICH WOULD CHANGE THE FORECAST FROM CHANCE OF RAIN...TO
STRONG WINDS. SO STAY TUNED. ONE THING FOR SURE...IT WILL BE
EXTREMELY COLD WITH THIS NEXT UPPER LOW. SNOW LEVELS COULD BE LOW
ENOUGH WHERE THE SANTA MONICA MTNS AND SANTA CLARITA COULD SEE A
DUSTING. THE TIMING OF THIS UPPER LOW WILL BE TRICKY AS
WELL...ESPECIALLY WITH NEW YEARS EVE AND PEOPLE CAMPING OUT FOR THE
ROSE PARADE. STAY TUNED AS WE GET CLOSER TO THIS FEATURE EARLY NEXT
WEEK AND GET A BETTER HANDLE ON WHAT TO EXPECT. OH AND...MERRY
CHRISTMAS.


&&

.AVIATION...25/2310Z...

AT 2305Z...THERE WAS NO INVERSION AT KLAX.

OVERALL...MODERATE CONFIDENCE IN 00Z TAF PACKAGE. HIGH CONFIDENCE IN
ALL SITES REMAINING VFR THRU THE TAF PERIOD DUE TO CONTINUED NORTH
TO NORTHEAST FLOW. ONLY MODERATE CONFIDENCE IN WIND FORECAST FOR
MOST TAF SITES AS GUSTY NORTHERLY WINDS MAY CONTINUE TO LINGER
LONGER THAN IN CURRENT FORECAST.

KLAX...MODERATE CONFIDENCE IN 00Z TAF. GUSTY NORTHERLY WINDS COULD
REMAIN A COUPLE HOURS LATER THAN CURRENT 03Z FORECAST. THERE IS A
15% CHANCE OF EASTERLY WINDS (5 TO 7 KNOTS) FRIDAY MORNING BETWEEN
12Z AND 18Z.

KBUR...MODERATE CONFIDENCE IN 00Z TAF. MODERATE CONFIDENCE IN MDT
LLWS/TURBULENCE DEVELOPING AFTER 12Z. THERE IS A CHANCE GUSTY NORTH
TO NORTHEAST WINDS COULD SURFACE BETWEEN 12Z AND 18Z.

&&

.MARINE...25/830 PM PST...

FOR THE OUTER WATERS...NORTHWEST TO NORTH WINDS HAVE BEGUN TO
DIMINISH. SO...HIGH CONFIDENCE IN SMALL CRAFT WINDS CONTINUING
THROUGH TONIGHT. FOR FRIDAY THROUGH SATURDAY...THE WINDS WILL
SHIFT TO A NORTHEASTERLY DIRECTION AND SHOULD REMAIN BELOW SMALL
CRAFT LEVELS. ONLY EXCEPTION MAY BE THE SOUTHERN OUTER WATERS WHERE
GUSTY NORTHEAST WINDS COULD EXTEND ACROSS THE WATERS...REACHING
SMALL CRAFT LEVELS. FOR SUNDAY THROUGH EARLY NEXT WEEK...CHANCE OF
SMALL CRAFT ADVISORY LEVEL NORTHERLY WINDS THROUGH THE PERIOD.

FOR THE INNER WATERS...NORTHWEST TO NORTH WINDS HAVE DIMINISHED AND
WIDESPREAD SMALL CRAFT WINDS ARE NOT EXPECTED. BY FRIDAY MORNING AND
CONTINUING THROUGH SATURDAY...THE WINDS WILL SHIFT TO THE NORTHEAST.
THERE IS A CHANCE OF SMALL CRAFT LEVEL WINDS FRIDAY MORNING ACROSS
THE NEAR SHORE WATERS FROM POINT MUGU TO SANTA MONICA. BY LATE
FRIDAY NIGHT AND SATURDAY...THE NORTHEAST WINDS WILL BE STRONGER AND
THERE IS A HIGHER CHANCE OF WIDESPREAD SMALL CRAFT LEVEL GUSTS FROM
VENTURA TO SANTA MONICA AND EVEN IMPACTING CATALINA ISLAND.

&&

.LOX WATCHES/WARNINGS/ADVISORIES...
FREEZE WARNING (SEE LAXNPWLOX).
WIND ADVISORY (SEE LAXNPWLOX).
SMALL CRAFT ADVISORY (SEE LAXMWWLOX).
HIGH RIP CURRENT RISK (SEE LAXSRFLOX).

&&

$$

PUBLIC...RAT
AVIATION/MARINE...RAT
SYNOPSIS...SUKUP

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