FXUS66 KLOX 100007 AAA
AFDLOX
SOUTHWEST CALIFORNIA AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE LOS ANGELES/OXNARD CA
407 PM PST WED DEC 9 2009
.SYNOPSIS...
RELATIVELY COLD TEMPERATURES WILL CONTINUE TONIGHT...WITH SLIGHT
WARMING EXPECTED THROUGH THE WEEK. A STORM SYSTEM WILL BRING A
CHANCE OF LIGHT TO MODERATE RAIN ON THURSDAY INTO EARLY
FRIDAY...SNOW LEVEL ABOVE 5500 FEET. ANOTHER STORM SYSTEM IS
EXPECTED TO AFFECT THE AREA OVER THE WEEKEND...WITH THE POTENTIAL
FOR MORE SIGNIFICANT RAINFALL.
&&
.SHORT TERM (TODAY-SAT)...OVERALL...IT LOOKS LIKE A RATHER WET
PERIOD THROUGH THE SHORT TERM...WITH TWO STORM SYSTEMS EXPECTED TO
AFFECT THE AREA.
THE FIRST SYSTEM WILL MOVE ACROSS THE AREA ON THURSDAY AND FRIDAY.
12Z PROGS ARE IN PRETTY GOOD AGREEMENT WITH THIS SYSTEM. DURING THE
DAY ON THURSDAY...EXPECT LIKELY POPS ACROSS SLO/SBA COUNTIES AND
CHANCE/SLIGHT CHANCE FOR VTU/LAX COUNTIES. BY THURSDAY NIGHT/FRIDAY
MORNING...LIKELY POPS ARE EXPECTED FOR ALL AREAS WITH THE RAIN THREAT
TAPERING OFF FRIDAY AFTERNOON. AT THIS TIME...THIS SYSTEM LOOKS
RATHER WEAK...WITH 0.25" TO 0.75" OF RAINFALL EXPECTED FOR MOST
AREAS. SNOW LEVELS WILL GENERALLY BE BETWEEN 5500 AND 6000 FEET WITH
2-4 INCHES OF SNOWFALL ACCUMULATION EXPECTED. WITH THE EXPECTED RAIN
AND SNOW AMOUNTS...DO NOT ANTICIPATE THE NEED FOR ANY WINTER WEATHER
OR FLASH FLOOD PRODUCTS AT THIS TIME.
FRIDAY AFTERNOON AND EVENING WILL BE A LULL IN THE ACTION WITH ONLY
SCATTERED SHOWERS EXPECTED ACROSS THE AREA. HOWEVER...BY LATE FRIDAY
NIGHT AND SATURDAY...A MORE POTENT STORM SYSTEM IS FORECAST TO ROLL
INTO THE AREA. 12Z GFS AND WRF BOTH INDICATE GOOD SOUTHERLY FLOW AND
DECENT PRECIPITABLE WATER AMOUNTS WITH THIS STORM ON SATURDAY AND
SATURDAY NIGHT WHICH SHOULD PRODUCE SOME PRETTY SIGNIFICANT
OROGRAPHIC RAINFALL. AT THIS TIME...RAIN WILL BECOME LIKELY DURING
THE DAY ON SATURDAY AND CONTINUE THROUGH SATURDAY NIGHT. PRELIMINARY
RAINFALL AMOUNTS WITH THIS SYSTEM WILL RANGE FROM 0.50" TO 1.50" FOR
COASTAL/VALLEY AREAS WITH 1.50" TO 2.50" IN THE FOOTHILLS AND
MOUNTAINS. SNOW LEVELS WILL REMAIN AROUND 6000 FEET ON
SATURDAY...THEN DROP TO AROUND 5500 FEET SATURDAY NIGHT.
.LONG TERM (SUN-WED)...FOR THE EXTENDED...EXPECT SCATTERED SHOWERS
ACROSS THE AREA ON SUNDAY IN THE WAKE OF THE STORM WITH SNOW LEVELS
AROUND 5000 FEET.
FOR MONDAY THROUGH WEDNESDAY...MODELS HAVE THE SAME GENERAL IDEA
BUT DIFFER NOTICEABLY ON THE DETAILS. ESSENTIALLY...AN UPPER LEVEL
RIDGE IS FORECAST TO DEVELOP OVER THE WEST COAST. AT THIS TIME...
THE GFS IS MORE BULLISH WITH THE RIDGE THAN THE ECMWF. EITHER WAY
WILL EXPECT THIS PATTERN TO PRODUCE DRY CONDITIONS ACROSS THE AREA
WITH A GRADUAL WARMING TREND WITH AFTERNOON TEMPS NEAR SEASONAL
NORMS ON TUESDAY AND WEDNESDAY.
&&
.AVIATION...10/0006Z.
VFR CONDITIONS ARE EXPECTED THROUGHOUT AT LEAST 14Z TUESDAY...THEN
MVFR CONDITIONS IN RAIN WILL DEVELOP FROM NORTH TO SOUTH BETWEEN 14Z
AND THURSDAY EVENING. BEST CHANCES OF RAIN AND MVFR CATEGORY
CONDITIONS ON THURSDAY WILL EXIST NORTH OF KNTD.
KLAX AND KBUR...CEILINGS ABOVE 6000 FEET WILL PERSIST THROUGH AT
LEAST 14Z...BECOMING PREVALENT BY 20Z THURSDAY. THERE IS A 20
PERCENT CHANCE OF MVFR CONDITIONS AFTER 20Z. MVFR CONDITIONS IN RAIN
SHOULD DEVELOP BETWEEN 01Z AND 07Z THURSDAY NIGHT. NO WIND ISSUES
ARE EXPECTED THROUGHOUT THE PERIOD.
&&
.LOX WATCHES/WARNINGS/ADVISORIES...
SMALL CRAFT ADVISORY (SEE LAXMWWLOX).
HIGH SURF ADVISORY (SEE LAXCFWLOX).
HIGH RIP CURRENT RISK (SEE LAXSRFLOX).
&&
$$
PUBLIC...THOMPSON
AVIATION...HALL
SYNOPSIS...MEIER
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