AREA FORECAST DISCUSSION

AREA FORECAST DISCUSSION
FXUS66 KLOX 182227
AFDLOX

SOUTHWEST CALIFORNIA AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LOS ANGELES/OXNARD CA
227 PM PST SUN FEB 18 2007

.SHORT TERM...COOL UPPER/MID LEVEL CYCLONIC FLOW JUST OFFSHORE WAS
REFLECTING OVER THE BIGHT EARLY THIS AFTERNOON WITH MODERATE
SOUTHEAST LOW LEVEL FLOW OVER THE OCEANSIDE OF THE TRANSVERSE
RANGE. MOISTURE HAS BECOME MORE AVAILABLE AND WAS ORIENTED IN A
FETCH THE WIDTH OF THE BIGHT AND EXTENDED SOUTH OF 28N. EXPECT
SHOWERS TO DEVELOP IN THE EVENING AND INCREASE OVERNIGHT AS THE
COOL MID/UPPER LEVEL AIR COINCIDES WITH THE AVAILABLE MOISTURE.
HAVE INDICATED SLIGHT CHANCE OF THUNDERSTORMS IN THE EVENING
THOUGH MID LEVEL CAP WILL LIKELY PERSIST THROUGH MONDAY MORNING
THEN MIX OUT THROUGH MIDDAY MONDAY COINCIDING WITH UPPER CENTER
MOVING ASHORE AND LOW LEVEL HEATING...CONVECTIVE INSTABILITY
REMAINS MARGINAL THOUGH ISOLATED THUNDERSTORMS ARE MORE LIKELY
MONDAY VS. TONIGHT. TEMPERATURES WERE 10 TO 20 DEGREES COOLER THAN
YESTERDAY AT THIS TIME. TEMPERATURES NORTH OF POINT CONCEPTION
WERE 5 TO 10 DEGREES BELOW NORMAL WITH SIMILAR DEGREE OF
DIFFERENCE ABOVE NORMAL SOUTH OF POINT CONCEPTION AT THIS TIME.
LEADING EDGE OF A COOLER AIR MASS WAS DIFFUSED AND MOVING OVER THE
WESTERN SANTA BARBARA CHANNEL AT THIS TIME. EXPECT A MIXED TREND
MONDAY WITH SLIGHT WARMING OVER THE NORTH HALF AND COOLING OVER
THE SOUTH HALF WITH HIGHS A COUPLE OF DEGREES BELOW NORMAL AND
NEARLY 10 DEGREES BELOW NORMAL OVER THE SOUTH HALF MONDAY. WILL
CONTINUE WITH WARMING TREND OVER THE ENTIRE WITH TEMPERATURES NEAR
NORMAL.

.LONG TERM...GUIDANCE WAS CONSISTENT WITH A LOW AMPLITUDE LONG
WAVE TROUGH DEVELOPING OVER THE CENTRAL PAC EARLY IN THE WEAK.
TROUGH IS EXPECTED TO PROGRESS EAST WHILE AMPLIFYING AND A COLD
FRONT WILL MOVE ASHORE THURSDAY. SNOW LEVELS ARE EXPECTED TO FALL
SHARPLY WITHIN THE FOLLOWING AIR MASS AND EXPECT FLURRIES OVER THE
FOOTHILLS OF THE COASTAL AND TRANSVERSE RANGES. SHOWERS WILL
LINGER THROUGH FRIDAY. TEMPERATURES WILL GRADUALLY MODERATE
THROUGH THE WEEKEND WARMING TO NEAR NORMAL BY SUNDAY.


&&

.AVIATION...VFR CIGS EXCEPT FOR KSBP AND KSMX WITH LOW MVFR CIGS THROUGH 20Z.
EXPECT BKN-OVC150-200 THROUGH MOST OF THE DAY. EXPECT LOWERING VFR
CIGS TO NEAR 070 WITH SOME LOCAL IFR TO MVFR CIGS...ESPECIALLY NEAR
THE COASTAL AIRFIRELDS THIS EVENING AND OVERNIGHT. SOME LIGHT
SHOWERS SHOULD DEVELOP NEAR 10Z IN THE SOUTH AND CIGS SHOULD REMAIN
IN MVFR WITH LOCAL CIGS IN IFR BY EARLY MORNING HOURS.

KLAX WILL EXPERIENCE SOUTHEAST WINDS NEAR 10 KT THIS
MORNING...BECOMING SW 12 KT FOR A BRIEF PERIOD THIS AFTERNOON. WINDS
SHOULD SHIFT BACK OUT OF THE SE BETWEEN 6 TO 12 KT THIS EVENING INTO
THE MORNING HOURS. LIGHT SHOWERS SHOULD DEVELOP BETWEEN 10Z-12Z
TOMORROW MORNING.


&&

.LOX WATCHES/WARNINGS/ADVISORIES...
CA...HIGH SURF ADVISORY (SEE LAXCFWLOX).
PACIFIC COASTAL WATERS...GALE WARNING (SEE LAXCWFLOX).
SMALL CRAFT ADVISORY (SEE LAXCWFLOX).

&&




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