Flash Flood Warning 28, NWS Los Angeles, CA

SOUTHWEST CALIFORNIA AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LOS ANGELES/OXNARD CA
145 PM PST FRI FEB 18 2005

.SHORT TERM...FIRST WAVE OF STEADY PRECIP HAS MOVED THROUGH THE
AREA. NOW WERE IN A BIT OF A LULL, THOUGH AIRMASS IS PRETTY
UNSTABLE SO SHOWERS OR THUNDERSTORMS COULD DEVELOP JUST ABOUT
ANYWHERE AT ANY TIME. AIRMASS IS ALSO QUITE MOIST SO ANY CONVECTION
HAS THE POTENTIAL FOR DROPPING QUITE A BIT OF PRECIP IN A SHORT
PERIOD OF TIME. SATELLITE IMAGERY SHOWS A COUPLE GOOD CONVECTIVE
CELLS JUST SOUTH OF SAN NICOLAS ISLAND AS WELL AS A LINE OF
CONVECTION TO THE WEST OF THE CENTRAL COAST. WITH THE FLOW ALOFT
GENERALLY OUT OF THE SOUTH, IT LOOKS LIKE THE CELLS TO THE SOUTH OF
SAN NICOLAS ISLAND HAVE THE BEST CHANCE FOR MAKING LANDFALL. IN ANY
CASE, SHOWERS AND THUNDERSTORMS ARE POSSIBLE ANYWHERE ACROSS OUR CWA
THIS AFTERNOON AND EVENING WITH LOCALLY VERY HEAVY RAIN POSSIBLE.

MODELS SHOW THE NEXT WAVE OF STEADY PRECIP ARRIVING LATER TONIGHT
AND SATURDAY, WITH THE FOCUS AGAIN SOUTH OF POINT CONCEPTION. RAIN
WILL START TO TAPER OFF LATER SATURDAY, BUT NUMEROUS SHOWERS ARE
EXPECTED TO CONTINUE THROUGH SUNDAY BEFORE THE NEXT AND PERHAPS
STRONGEST WAVE OF PRECIP ARRIVES LATER SUNDAY AND MONDAY. THIS LAST
WAVE COULD POTENTIALLY BRING SOME VERY HEAVY RAIN AND SERIOUS
FLOODING CONCERNS.

BASED ON THE FLOODING ISSUES THIS MORNING OVER VENTURA COUNTY AND
THE EXPECTED HEAVY RAIN LATER TONIGHT AND SATURDAY AND AGAIN MONDAY,
WEVE ISSUED A FLOOD WATCH FOR AREAS SOUTH OF POINT CONCEPTION
THROUGH TUESDAY. NOT REALLY CONCERNED YET WITH THE MAIN STEM RIVERS,
BUT THE SMALLER CREEKS AND STREAMS, AS WELL AS THE BURN AREAS WILL
REALLY BE AT RISK FOR SOME FLOODING PROBLEMS, ESPECIALLY SATURDAY
AND MONDAY.

SNOW LEVELS HAVE COME DOWN A BIT, BUT ACCUMULATIONS HAVE BEEN RATHER
LIGHT SO FAR, GENERALLY 6 INCHES OR LESS AT RESORT LEVELS. ITS A
VERY WET SNOW AND THIS IS PROBABLY LIMITING THE ACCUMULATIONS SO
FAR. AS COLDER AIR ARRIVES OVER THE NEXT 24 TO 48 HOURS, SNOW LEVELS
WILL LOWER AND ACCUMULATIONS WILL INCREASE. CURRENT WINTER WEATHER
ADVISORY MAY NEED TO BE UPGRADED TO A WINTER STORM WARNING AT SOME
POINT THIS WEEKEND. SNOW LEVELS WILL BOTTOM OUT MONDAY AND TUESDAY
AROUND 5000 FEET.

.LONG TERM...LAST BATCH OF STEADY RAIN SHOULD START TO TAPER OFF
LATER MONDAY INTO TUESDAY AS THE FLOW ALOFT SHIFTS TO THE NORTHWEST
AND THE UPPER LOW FINALLY MOVES TO OUR EAST. STILL COULD SEE SOME
DECENT SHOWER AND THUNDERSTORM ACTIVITY THROUGH TUESDAY AS THE
AIRMASS DESTABILIZES EVEN FURTHER. THINGS STILL LOOK DRY WEDNESDAY
AND THURSDAY.

&&

.LOX WATCHES/WARNINGS/ADVISORIES...
FLOOD WATCH (SEE LAXFFALOX).
FLOOD ADVISORY (SEE LAXFLSLOX).
WINTER WEATHER ADVISORY (SEE LAXWSWLOX).
MARINE WEATHER STATEMENT (SEE LAXMWSLOX).
SMALL CRAFT ADVISORY (SEE LAXCWFLOX).

&&

WOFFORD

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE LOS ANGELES/OXNARD CA
600 AM PST FRI FEB 18 2005

CAZ034>041-044>047-051>054-059-087-088-191400-
SAN LUIS OBISPO COUNTY CENTRAL COAST-
SANTA BARBARA COUNTY CENTRAL COAST-SANTA YNEZ VALLEY-
SAN LUIS OBISPO COUNTY INTERIOR VALLEYS-CUYAMA VALLEY-
SANTA BARBARA COUNTY SOUTH COAST-VENTURA COUNTY COAST-
LOS ANGELES COUNTY COAST INCLUDING DOWNTOWN LOS ANGELES-
VENTURA COUNTY INTERIOR VALLEYS-VENTURA COUNTY COASTAL VALLEYS-
SANTA MONICA MOUNTAINS RECREATIONAL AREA-
LOS ANGELES COUNTY VALLEYS-SAN LUIS OBISPO COUNTY MOUNTAINS-
SANTA BARBARA COUNTY MOUNTAINS-VENTURA COUNTY MOUNTAINS-
LOS ANGELES COUNTY MOUNTAINS EXCLUDING THE SANTA MONICA RANGE-
ANTELOPE VALLEY-CATALINA ISLAND-SANTA CLARITA VALLEY-
600 AM PST FRI FEB 18 2005

THIS HAZARDOUS WEATHER OUTLOOK IS FOR SOUTHWESTERN CALIFORNIA.

.DAY ONE...TODAY

PERIODS OF RAIN WILL CONTINUE TODAY. SOME OF THE RAIN WILL BE HEAVY
THIS MORNING...POSSIBLY CAUSING SOME LOCAL FLOODING ON ROADWAYS AND
IN INTERSECTIONS. ROCKSLIDES AND MUDSLIDE MAY ALSO POSE A PROBLEM.

SNOW WILL FALL ACROSS THE MOUNTAINS OF LOS ANGELES AND VENTURA
COUNTIES TODAY. SNOW LEVELS EARLY THIS MORNING WERE AVERAGING 7000
TO 7500 FEET...BUT ARE EXPECTED TO LOWER TO AROUND 6500 FEET LATER
TODAY. 6 TO 10 INCHES OF SNOW ARE EXPECTED ABOVE 7000 FEET THROUGH
TONIGHT. GUSTY SOUTH TO SOUTHEAST WINDS 20 TO 30 MPH WITH GUSTS OVER
50 MPH WILL CAUSE BLOWING AND DRIFTING OF THE SNOW AND REDUCE
VISIBILITIES TO NEAR ZERO AT TIMES.

SCATTERED THUNDERSTORMS WILL AFFECT THE COASTAL WATERS TODAY.
SOME OF THESE THUNDERSTORMS WILL PRODUCE WIND GUSTS IN EXCESS OF
35 KNOTS...SMALL HAIL...VERY HEAVY RAIN...AND ROUGH SEAS.

* WINTER WEATHER ADVISORY....SEE WWUS46 KLOX - WSWLOX FOR DETAILS *

* MARINE WEATHER STATEMENT...SEE FZUS76 KLOX - MWSLOX FOR DETAILS *

.DAYS TWO THROUGH SEVEN... SATURDAY THROUGH THURSDAY

PERIODS OF RAIN ARE EXPECTED SATURDAY THROUGH TUESDAY.
RAIN MAY BE HEAVY AT TIMES...ESPECIALLY SATURDAY MORNING...
AND AGAIN SUNDAY NIGHT THROUGH MONDAY NIGHT. RAIN MAY BE HEAVY
ENOUGH TO CAUSE SOME FLOODING ACROSS THE AREA. WITH THE GROUND
ALREADY SATURATED BY THE VERY WET WEATHER SO FAR THIS WINTER...
ADDITIONAL RAIN WILL INCREASE THE RISK OF ROCK AND MUDSLIDE
ACTIVITY...AS WELL AS MUD AND DEBRIS FLOWS NEAR THE BURN AREAS.

IN THE MOUNTAINS OF LOS ANGELES AND VENTURA COUNTIES...PERIODS
OF SNOW WILL CONTINUE THROUGH SUNDAY MORNING. SNOW LEVELS
WILL BE BETWEEN 6000 AND 6500 FEET SATURDAY...THEN LOWER TO 5500
FEET SATURDAY NIGHT AND SUNDAY MORNING. TOTAL SNOW ACCUMULATIONS
THROUGH SUNDAY SHOULD RANGE FROM 15 TO 30 INCHES ABOVE 7000 FEET.
LESSER ACCUMULATIONS OF 6 TO 12 INCHES CAN BE EXPECTED BETWEEN 6000
AND 7000 FEET. GUSTY SOUTHEAST TO SOUTH WINDS OF 20 TO 30 MPH WITH
LOCAL GUSTS OVER 40 MPH AT TIMES WILL CONTINUE THROUGH
SATURDAY NIGHT. THE COMBINATION OF BLOWING SNOW AND DENSE FOG COULD
REDUCE VISIBILITIES TO NEAR ZERO AT TIMES.

* WINTER WEATHER ADVISORY....SEE WWUS46 KLOX - WSWLOX FOR DETAILS *

.SPOTTER INFORMATION STATEMENT...

WEATHER SPOTTERS ARE ENCOURAGED TO REPORT SIGNIFICANT WEATHER
CONDITIONS ACCORDING TO STANDARD OPERATING PROCEDURES.

BRUNO