Weather Service Report


798 
FXUS66 KLOX 230603
AFDLOX

SOUTHWEST CALIFORNIA AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LOS ANGELES/OXNARD CA
940 PM PST SAT NOV 22 2014

...AVIATION DISCUSSION UPDATED...

.SYNOPSIS...

THERE WILL BE A SLIGHT CHANCE OF SHOWERS THIS EVENING ACROSS THE 
NORTH MOUNTAIN SLOPES...AND PARTLY CLOUDY SKIES OVER THE CENTRAL 
COAST THIS EVENING. OTHERWISE...MOSTLY CLEAR SKIES CAN BE EXPECTED 
THROUGH NEXT WEEK. OFFSHORE WINDS WILL PERSIST THROUGH AT LEAST MID 
WEEK AND WILL ALLOW FOR WARMER THAN NORMAL TEMPERATURES FOR COAST 
AND VALLEYS. SOME COOLING IS EXPECTED LATE NEXT WEEK.

&&

.SHORT TERM (TONIGHT-WED)...A DISSIPATING COLD FRONT WAS MOVING THRU 
SLO/SBA COUNTIES THIS EVENING WITH SOME CLOUDINESS. THERE WERE ALSO 
CLOUDS BANKED UP ON THE N MTN SLOPES ALONG WITH A FEW VERY LIGHT 
RAIN AND AND SNOW SHOWERS. THE CLOUDINESS IS EXPECTED TO DISSIPATE 
LATE TONIGHT AND EARLY SUN AS A DRY NORTHERLY FLOW INCREASED ACROSS 
THE AREA. GUSTY NW TO N WINDS WILL PREVAIL OVER THE SBA COUNTY S 
COAST AND MTNS TONIGHT...WHERE WIND ADVISORIES ARE IN EFFECT. GUSTY 
NW TO N WINDS WERE ALSO NOTED ACROSS THE VTU/L.A. COUNTY MTNS 
ESPECIALLY ALONG THE I-5 CORRIDOR. GUSTY W WINDS WILL PERSIST FOR A 
WHILE OVERNIGHT IN THE ANTELOPE VALLEY AS WELL. AS THE NIGHT 
PROGRESSES...N WINDS WILL INCREASE ACROSS MANY OF THE VLYS AND SOME 
COASTAL AREAS OF VTU/L.A. COUNTIES AS WELL AS THE SANTA MONICA MTNS. 
WIND ADVISORIES HAVE ALREADY BEEN ISSUED FOR MANY OF THESE AREAS. IN 
ADDITION...WITH THE WINDS COMBINED WITH DRIER AIR...THERE IS A RED 
FLAG WARNING IN EFFECT FOR THE SBA S COAST AND MTNS TONIGHT INTO SUN 
MORNING.

AN UPPER LEVEL RIDGE WILL BUILD OFF THE CA COAST THRU MON THEN BUILD 
SLOWLY E INTO THE CA COAST FOR TUE. SURFACE HIGH PRESSURE WILL BUILD 
INTO THE GREAT BASIN OVER THE NEXT COUPLE OF DAYS...BRINGING GUSTY 
NE SANTA ANA WINDS TO SWRN CA. THERE IS SUPPORT FOR ADVISORY LEVEL 
WINDS OVER A LARGE PORTION OF VTU/L..A. COUNTIES SUN INTO MON 
AFTERNOON...WITH GOOD OFFSHORE PRESSURE GRADIENTS...AND DECENT COLD 
AIR ADVECTION AT 850 MB. WIND ADVISORIES WILL CONTINUE FOR THE MTNS 
OF VTU/L.A. COUNTIES INCLUDING THE SANTA MONICA RANGE...THE VTU 
COUNTY VLYS...THE SANTA CLARITA VLY...AND SAN FERNANDO VLY FOR SUN 
INTO MON AFTERNOON. THERE MAY BE A BRIEF LULL IN THE STRONGEST WINDS 
SUN EVENING...BUT THE WINDS WILL INCREASE AGAIN LATER SUN NIGHT INTO 
MON. THERE WILL ALSO BE GUSTY WINDS AT TIMES FOR THE VTU COUNTY 
COASTAL AREAS...AND BELOW PASSES AND CANYONS OF THE L.A. COUNTY 
COAST FROM MALIBU TO THE HOLLYWOOD HILLS...BUT WINDS SHOULD BE 
BORDERLINE ADVISORY LEVELS. FOR MORE INFORMATION ON THE WIND 
ADVISORIES...PLEASE SEE THE LATEST NON-PRECIPITATION WEATHER MESSAGE 
(LAXNPWLOX).

IT LOOKS LIKE EVEN STRONGER SURFACE HIGH PRESSURE WILL BUILD INTO 
UTAH AND COLORADO (1040 MB) MON NIGHT INTO TUE MORNING...RESULTING 
IN ADDITIONAL GUSTY WINDS ACROSS MUCH OF VTU/L.A. COUNTIES...AND THE 
LIKELIHOOD OF MORE WIND ADVISORIES...POSSIBLY FOR COASTAL AREAS AS 
WELL. SOME LOCATIONS MAY EVEN APPROACH HIGH WIND WARNING THRESHOLDS 
AT TIMES...ESPECIALLY IN THE FOOTHILLS AND HIGHER TERRAIN. NEEDLESS 
TO SAY...ALL THIS OFFSHORE FLOW WILL BLOW ANY MARINE LAYER CLOUDS 
WELL OFF THE COAST WITH MOSTLY CLEAR SKIES PREVAILING IN ALL AREAS 
SUN THRU TUE. THE WINDS AND MUCH DRIER AIR MOVING INTO THE REGION 
HAS ALSO PROMPTED THE ISSUANCE OF FIRE WEATHER WATCHES FOR MOST OF 
VTU/L.A. COUNTIES FROM SUNDAY EVENING THROUGH TUESDAY AFTERNOON. 
PLEASE SEE THE LATEST FIRE WEATHER MESSAGE (LAXRFWLOX) FOR FURTHER 
DETAILS ON THE RED FLAG WARNINGS AND FIRE WEATHER WATCHES CURRENTLY 
IN EFFECT.

AS FAR AS TEMPS OVER SWRN CA...HIGHS WILL WARM TO NEAR NORMAL TO 
SLIGHTLY ABOVE NORMAL ON SAT...THEN INCREASE FURTHER ON SUN TO 
SEVERAL DEGREES ABOVE NORMAL MOST AREAS. HOWEVER...THE INTERIOR 
VALLEYS...MTNS AND DESERTS WILL REMAIN NEAR NORMAL TO SLIGHTLY BELOW 
NORMAL OVER THE WEEKEND. FOR MON...TEMPS WILL WARM TO SIGNIFICANTLY 
ABOVE NORMAL FOR THE COAST AND VLYS WITH SOME LOWER 80S POSSIBLE IN 
THE WARMEST CST AND VLYS...WHILE INTERIOR VLYS...MTNS AND DESERTS 
WILL BE NEAR NORMAL FOR THE MOST PART.

***FROM PREVIOUS DISCUSSION***

WED WILL BE JUST LIKE TUESDAY EXCEPT A LITTLE LESS WINDY AND LITTLE 
WARMER AS THE SFC GRADS RELAX (BUT REMAIN OFFSHORE) AND THE HGTS 
RISE TO 588 DM AS THE RIDGE AXIS MOVES OVER CALIFORNIA. RIGHT NOW 
HAVE PLENTY OF MID TO UPPER 80S IN THE FCST BUT WOULD NOT BE 
SURPRISED TO SEE SOME 90 DEGREES READINGS. 

.LONG TERM (THU-SAT)...
BOTH GFS AND EC AGREE THAT THE RIDGE WILL SLOWLY PUSH TO THE EAST 
THU AND FRI. MORE IMPORTANTLY THE OFFSHORE FLOW RELAXES. SKIES WILL 
REMAIN MOSTLY CLEAR. MAX TEMPS WILL COOL A LITTLE EACH DAY (MORE 
THAN A LITTLE RIGHT AT THE COAST) BUT WILL REMAIN ABOVE NORMAL.

SATURDAYS FORECAST IS QUESTIONABLE THE EC BRINGS IN A SLIGHT RIDGE 
WHILE THE GFS BRINGS A TROF TO THE EAST PAC. DID NOT REALLY BITE 
HARD ON EITHER SOLN AND JUST TRENDED THE FCST COOLER AND A LITTLE 
CLOUDIER.

&&

.AVIATION...23/06Z...

AT 0525Z AT KLAX...THERE WAS NO INVERSION.

OVERALL...MODERATE TO HIGH CONFIDENCE IN THE 06Z TAFS.  AT KPRB 
08Z-17Z THERE IS A THIRTY FIVE PERCENT CHANCE OF IFR CONDITIONS.  AT 
KSBA THROUGH 14Z THERE IS A SIXTY PERCENT CHANCE OF LOW LEVEL WIND 
SHEAR AND AT KBUR AND KVNY THROUGH 12Z THERE IS A TWENTY PERCENT 
CHANCE OF LOW LEVEL WIND SHEAR.  OTHERWISE AND ELSEWHERE VFR 
CONDITIONS WILL PREVAIL.

KLAX...HIGH CONFIDENCE IN THE 06Z TAF.  VFR CONDITIONS WILL PREVAIL 
THROUGHOUT THE FORECAST PERIOD.  THROUGH 20Z NE TO E WINDS LESS THAN 
10 KNOTS.

KBUR...HIGH CONFIDENCE IN THE 06Z TAF.  VFR CONDITIONS WILL PREVAIL 
THROUGHOUT THE FORECAST PERIOD.  THROUGH 12Z NE WINDS WITH A TWENTY 
PERCENT CHANCE OF LOW LEVEL WIND SHEAR.

&&

.MARINE...22/800 PM PST...
HIGH CONFIDENCE THAT MODERATE NORTHWEST WINDS WILL CONTINUE OVER THE 
OUTER WATERS THROUGH LATE SUNDAY NIGHT...ALTHOUGH WINDS MAY WEAKEN 
SOME FOR A FEW HOURS LATE SUNDAY MORNING INTO EARLY AFTERNOON. 
MODERATE WEST TO NORTHWEST WINDS WILL ALSO CONTINUE OVER THE WESTERN 
SANTA BARBARA CHANNEL THROUGH LATE TONIGHT. GOOD CONFIDENCE THAT THE 
WESTERLY WINDS WILL SUBSIDE AS OFFSHORE FLOW BEGINS BY EARLY SUNDAY 
MORNING. THERE IS A MODERATE CHANCE THAT NORTHEAST GUSTS OF 25 KNOTS 
OR MORE WILL DEVELOP CLOSE TO SHORE BETWEEN VENTURA HARBOR AND POINT 
MUGU SUNDAY MORNING. MODERATE TO HIGH CHANCE THAT SCA GUSTS AND 
SHORT PERIOD SEAS WILL AFFECT THE WATERS FROM MALIBU TO SANTA MONICA 
AND WESTWARD BEYOND ANACAPA ISLAND SUNDAY MORNING INTO EARLY 
AFTERNOON. THE SAN PEDRO CHANNEL IS EXPECTED TO HAVE MAINLY LIGHT 
WINDS TOMORROW. THE OFFSHORE WIND SCENARIO IS LIKELY TO REPEAT 
MONDAY MORNING. BY TUESDAY MORNING THE WIND DIRECTION WILL SHIFT TO 
ENE AND THE LOCATION OF STRONGER WINDS MAY SHIFT UP TO THE VENTURA 
NEAR-SHORE WATERS. SEAS GENERATED OVER THE EASTERN PACIFIC WITHIN 
290-300 DEGREES RELATIVE TO THE AREA WILL ARRIVE THIS EVENING AND 
CREATE SCA CONDITIONS FOR HAZARDOUS SEAS ALONG THE CENTRAL COAST AND 
EXTENDING SOUTH TO SAN CLEMENTE ISLAND THROUGH SUNDAY NIGHT.  

&&

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

&&

$$

PUBLIC...SIRARD/RORKE
AVIATION...KJ
MARINE...SMITH
SYNOPSIS...SWEET/SIRARD

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