AREA FORECAST DISCUSSION
FXUS66 KLOX 211238 CCA
AFDLOX

SOUTHWEST CALIFORNIA AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LOS ANGELES/OXNARD CA
400 AM PST MON FEB 21 2005



...SOUTHLAND STILL UNDER THE GUN FOR PERIODS OF HEAVY RAIN WITH BLIZZARD-LIKE CONDITIONS ABOVE 6000 FEET...

.SHORT TERM...THE LARGE UPPER LEVEL STORM SYSTEM THAT HAS PRODUCED HIGH WINDS...HEAVY DOWNPOURS AND SNOW MEASURE IN FEET IN THE MOUNTAINS IS STILL LOCATED 280 NM NORTHWEST OF POINT CONCEPTION THIS MORNING. IN 24 HOURS...THE STORM CENTER IS STILL EXPECTED TO BE LOCATED ROUGHLY 125 NM WEST OF POINT CONCEPTION. IN FACT...IT NOW LOOKS LIKE THE UPPER LEVEL SYSTEM WILL NOT MOVE THROUGH SOUTHERN CALIFORNIA UNTIL WEDNESDAY. THIS MEANS THAT WE ARE STILL UNDER THE GUN FOR MORE WIND...RAIN AND SNOW.

IN THE LAST 12 HOURS...OVER AN INCH OF RAIN HAS BEEN MEASURED ALONG THE SOUTH FACING COASTAL SLOPES FROM WESTERN SANTA BARBARA COUNTY THROUGH LOS ANGELES COUNTY...WITH LOCAL AMOUNTS UP TO 6 AND A HALF INCHES AT OLD MAN MOUNTAIN ON THE BORDER BETWEEN VENTURA AND SANTA BARBARA COUNTIES. IN LOS ANGELES COUNTY...5 INCHES OF RAIN HAS BEEN MEASURED AT OPIDS CAMP IN THE SAN GABRIEL MOUNTAINS. ALONG THE COASTS...MOST LOCATIONS HAVE SEEN BETWEEN 1 AND 1 AND A HALF INCHES IN THE LAST 12 HOURS. SNOW REPORTS ARE STILL NOT VAILABLE...BUT WE ARE EXPECTING NEW ACCUMULATIONS OF ONE TO TWO FEET OR MORE OVERNIGHT AT ELEVATIONS ABOVE 6500 FEET.


AT THIS TIME IT LOOKS LIKE THE HEAVIEST RAINS HAVE MOVED ONSHORE OVER THE REGION...BUT MORE RAIN IS EXPECTED TODAY WITH POSSIBLE THUNDERSTORM ACTIVITY. THIS WILL PRODUCE LOCAL DOWNPOURS WHICH WILL ONLY SERVE TO ADD TO THE MASSIVE AMOUNT OF FLOODING AND MUDSLIDES THAT OCCURRED OVERNIGHT. IN THE NEXT 24 HOURS...WE ARE STILL LOOKING AT 2 TO 5 INCHES OF ADDITIONAL RAINFALL ACCUMULATION ON THE COASTAL SLOPES AND 1 TO 2 INCHES ALONG THE COAST. THE HEAVIEST RAINS ARE STILL LIKELY TO CENTER ON THE VENTURA AND SANTA BARBARA COUNTY LINE.

IN ADDITION TO THE FLOODING AND NUMEROUS MUDSLIDES THAT HAVE OCCURRED...HEAVY RAINS ARE EXPECTED TO BRING BOTH THE SANTA YNEZ AND THE SANTA CLARA RIVERS TO FLOOD STAGE LATER TO THIS MORNING. FOR DETAILS ON RIVER FLOODING...CONSULT THE LAXFLSLOX.

TRONG WINDS HAVE BEEN WIDESPREAD THIS MORNING...WITH WINDS AT SOME MOUNTAIN LOCATIONS GUSTING TO OVER 70 MPH AT CHILAO IN THE SAN GABRIEL MOUNTAINS. THE LATEST GUSTS AT CHILAO WERE DOWN TO 50 MPH. IN ANY CASE...WITH THE HEAVY SNOW OCCURRING IN THE MOUNTAINS...LOOK FOR BRUTAL WINTER WEATHER CONDITIONS...ESPECIALLY ABOVE 6000 FEET.

ELSEWHERE...WINDS ALONG THE COAST HAVE BEEN VERY GUSTY WITH GUSTS IN THE 30S TO 45 MPH. THUS...A WINTER STORM WARNING IS IN EFFECT FOR THE MOUNTAINS WITH WIND ADVISORIES JUST ABOUT EVERYWHERE ELSE BUT THE DESERT.

LOOK FOR UNSTABLE CONDITIONS TODAY WITH THE CHANCE FOR THUNDERSTORMS AND THE POSSIBILITY OF WATERSPOUTS AND SMALL TORNADOS. PRIME LOCATIONS WILL BE COASTAL COMMUNITIES FROM VENTURA COUNTY SOUTH TO THE ORANGE COUNTY LINE.

EXTENDED...MODELS ARE IN PRETTY GOOD AGREEMENT THROUGH SUNDAY BEFORE DIVERGING. LOOK FOR THE LOW CENTER TO MOVE TO OUR EAST AND LINGER OVER THE GREAT BASIN FROM THURSDAY INTO THE WEEKEND. WE WILL SEE SOME CYCLONIC CIRCULATION OVER THE REGION THROUGH FRIDAY...SO WE ARE CAUTIOUSLY DROPPING MENTION OF SHOWERS ON THOSE DAYS...BUT WILL NEED TO KEEP AN EYE ON THINGS AS THE WEEK PROGRESSES. A MINOR RIDGE TRIES TO SET UP OVER US ON SATURDAY...SO THE WEEKEND MAY BE DRY. HOWEVER...THERE IS SUFFICIENT UNCERTAINTY DUE TO THE PROXIMITY OF THE EXITING LOW AND MODEL DISAGREEMENT SUCH THAT SHOWERS MAY CREEP BACK INTO THE WEEKEND FORECAST BEFORE THE WEEK IS OVER.



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.LOX WATCHES/WARNINGS/ADVISORIES...

FLOOD WATCH (SEE LAXFFALOX).

WINTER STORM WARNING (SEE LAXWSWLOX).

WIND ADVISORY (SEE LAXNPWLOX).

RIVER FLOOD WARNING (LAXFLWLOX).

MARINE WEATHER STATEMENT (SEE LAXMWSLOX).

GALE WARNING/SMALL CRAFT ADVISORY (SEE LAXCWFLOX).



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DANIELSON