000
FXUS66 KLOX 151145 AAA
AFDLOX

SOUTHWEST CALIFORNIA AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE LOS ANGELES/OXNARD CA
445 AM PDT MON SEP 15 2008

UPDATED AVIATION SECTION

.SHORT TERM...
MARINE LAYER STRUGGLING TO FORM EARLY THIS MORNING SOUTH OF POINT
CONCEPTION. ACARS SHOWS THAT THE MARINE LAYER HAS SHRUNK TO ABOUT
700 FEET AND WITH NEAR 2MB OFFSHORE TRENDS IT LOOKS LIKE MOST AREAS
WILL SEE A SUNNY DAY. LOW CLOUDS DO COVER THE CENTRAL COAST AND THE
MARINE LAYER THERE HAS SHRUNK ENOUGH TO PRODUCE DENSE FOG. HEAT IS
THE NAME OF THE GAME TODAY WITH LOTS OF SUNSHINE...VERY WEAK ONSHORE
FLOW AND AN AFTERNOON BL OF 31 DEGREES C. LOOK FOR ALL AREAS SAVE
THE BEACHES TO SEE A NICE JUMP IN TEMPS WITH TRIPLE DIGIT READINGS
IN THE WARMEST VLY LOCATIONS AND 90 DEGREE READINGS IN THE INTERIOR
COASTAL SECTIONS.

EVEN LESS OF A MARINE LAYER TONIGHT RIGHT ALONG THE CENTRAL COAST
AND PATCHY ALONG THE LA. COAST LATE AND THATS IT. A VERY STRONG
INVERSION WILL MEAN THAT SOME LOWS WILL REMAIN IN THE LOWER 70S.

TUESDAY LOOKS TO BE AN INTERESTING DAY. CONTINUED VERY HOT WITH
LITTLE IN THE WAY OF A MARINE LAYER AND LOW LEVEL FLOW NEAR NEUTRAL.
BUT AN UPPER LOW WHICH IS NOW HARMLESSLY SPINNING JUST OFF OF SAN
FRANCISCO WILL OPEN UP AND MOVE THROUGH NRN CA. NEW MDLS DO BRING
SOME MID LEVEL MOISTURE INTO THE AREA DURING PEAK HEATING AND WITH
THE MTN LI`S HITTING -4 IN THE AFTERNOON CANNOT RULE OUT CONVECTION
AND ADDED A SLIGHT CHC.

AS THE TROF MOVES OUT OF CALIFORNIA LATER TUESDAY IT WILL INCREASE
THE ONSHORE FLOW AND ENHANCE THE MARINE LAYER WHICH SHOULD COVER ALL
THE COASTAL SECTIONS ALTHOUGH THE SBA SOUTH COAST IS NOT GOING TO BE
A SLAM DUNK. LOWER HGTS A DEEPER MARINE LAYER AND BETTER ONSHORE
FLOW WILL CAUSE A NICE COOL DOWN WITH SOME INLAND COASTAL TEMPS
FALLING 10 OR MORE DEGREES.

.FIRE WX...

CURRENT RED FLAG WARNING WILL NEED LOOKING INTO THIS MORNING. RH`S
HAVE CREPT UP A LITTLE AND NEW MDL SOLNS LOOK A LITTLE MORE MOIST
THAN THEY DID SUNDAY.

.LONG TERM...
GFS AND EC CAN ONLY AGREES THROUGH THURSDAY EVENING AND THEN DIVERGE
AS THEY ATTEMPT TO HANDLE A SMALL LOW MOVING INTO SOUTHERN OREGON.
THE GFS IS AS USUAL CUT OFF HAPPY AND KEEPS THE LOW TIGHTLY BUNCHED
AND MOVES IT DOWN THE CA COAST WHILE THE EC OPENS IT UP AND MOVES IT
INTO IDAHO. GFS ENSEMBLES INDICATE THAT THE GFS SOLN IS QUESTIONABLE
AND LEANED TO THE EC FOR LONG RANGE GUIDANCE. THAT SAID LOOK FOR
TROFING PATTER THROUGH FRIDAY WHICH SHOULD GIVE US NIGHT AND MORNING
CLOUDS OVER THE COASTS AND MOST OF THE VLYS. HIGHER HGTS SHOULD
BUILD IN FOR THE WEEKEND AND SMOOSH THE MARINE LAYER WHILE RISING
HGTS WILL WARM THINGS UP.

&&

.AVIATION...15/1145Z...VFR CONDITIONS WILL LIKELY BE PREDOMINANT
THROUGHOUT THE PERIOD AT TERMINALS SOUTH OF POINT
CONCEPTION...EXCEPT FOR A FEW HOURS OF OCCASIONAL MVFR VISIBILITIES
IN HAZE THROUGH 17Z THIS MORNING. NORTH OF POINT CONCEPTION...LIFR
TO IFR CONDITIONS WILL PERSIST THROUGH 16Z AT COASTAL
TERMINALS...WITH A CHANCE THAT THESE CONDITIONS MAY NOT CLEAR UNTIL
AROUND 20Z. LOW CONFIDENCE FORECAST EXISTS FOR MARINE LAYER
RETURNING TONIGHT AT COASTAL TERMINALS NORTH OF POINT
CONCEPTION...BUT IT IS LIKELY THAT IFR CONDITIONS MAY RETURN
SLIGHTLY EARLIER AT KSBP AND KSMX TONIGHT.

KLAX...VFR CONDITIONS WILL BE PREDOMINANT THROUGHOUT THE PERIOD. A
60 PERCENT CHANCE OF MVFR VISIBILITIES DEVELOPING EXISTS BETWEEN 14Z
AND 17Z. A 20 PERCENT CHANCE EXISTS THAT IFR CEILINGS MAY PUSH INTO
KLAX BETWEEN 13Z AND 17Z.

KBUR...VFR CONDITIONS ARE EXPECTED THROUGHOUT THE PERIOD.

&&

.LOX WATCHES/WARNINGS/ADVISORIES...
RED FLAG WARNING (SEE LAXRFWLOX).
FIRE WEATHER WATCH (SEE LAXRFWLOX).
GALE WARNING (SEE LAXMWWLOX).
SMALL CRAFT ADVISORY (SEE LAXMWWLOX).

&&

$$

PUBLIC...RORKE
AVIATION...HALL

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