HAZARDOUS WEATHER OUTLOOK
Issue Date: 517 PM PST SAT DEC 5 2009
Expiration: 600 AM PST SUN DEC 06 2009
THIS HAZARDOUS WEATHER OUTLOOK IS FOR SOUTHWESTERN CALIFORNIA.
.DAY ONE... THROUGH TONIGHT
NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.
.DAYS TWO THROUGH SEVEN... SUNDAY THROUGH FRIDAY
THE FIRST OF A SERIES OF STORM SYSTEMS WILL MOVE OVER THE AREA ON
MONDAY BRINGING AT LEAST ONE HALF INCH TO ONE AND ONE HALF INCHES OF
RAIN THROUGH MONDAY NIGHT. LOCAL AMOUNTS COULD EXCEED 3 INCHES
ACROSS SOUTH AND SOUTHWEST FACING SLOPES. DUE TO THE SYSTEM
SOUTHERLY FLOW COMPONENT...A THREAT OF MODERATE TO POSSIBLY HEAVY
RAINFALL AMOUNTS EXISTS FOR THE RECENT BURN AREA OF SANTA
BARBARA...VENTURA...AND LOS ANGELES COUNTIES. SNOW LEVELS WILL LOWER
TO NEAR 4000 FEET EARLY MONDAY THEN RISE TO 6000 FEET MONDAY
AFTERNOON. SNOWFALL AMOUNTS IN THE HIGHER MOUNTAIN ELEVATIONS ARE
GENERALLY EXPECTED TO RANGE BETWEEN 6 TO 12 INCHES WITH AMOUNTS
POSSIBLY UP TO 18 INCHES AT THE HIGHEST ELEVATIONS WITH THIS FIRST
STORM. SNOW LEVELS SHOULD LOWER QUICKLY TO NEAR 2000 FEET MONDAY
NIGHT WITH POSSIBLE SNOWFALL OVER PORTIONS OF THE ANTELOPE VALLEY
AND CUYAMA VALLEY. A SECOND STORM WILL LIKELY IMPACT SOUTHERN AND
CENTRAL CALIFORNIA FOR MID-TO-LATE WEEK. DUE TO THIS SYSTEMS
SUBTROPICAL COMPONENT...THIS SYSTEM WILL LIKELY BE MORE POWERFUL...
WARMER...AND A MORE EFFICIENT RAIN MAKER. HOWEVER...THERE STILL
EXISTS SOME UNCERTAINTY IN THE EXACT PLACEMENT OF HEAVIER RAINFALL
ACROSS THE AREA. IN ADDITION TO THE POTENTIAL FOR HEAVY RAIN...THERE
WILL LIKELY BE LARGE SWELL AND HIGH SURF CONDITIONS FOR THE COASTAL
WATERS. FOR UPDATES ON THE DEVELOPING WET AND POTENTIALLY HAZARDOUS
WEATHER PATTERN...STAY TUNED TO NOAA WEATHER RADIO OR YOUR FAVORITE
MEDIA SOURCE...OR LOG ON TO WWW.WEATHER.GOV ON THE INTERNET.
* WINTER STORM WATCH.........SEE WWUS46 KLOX - WSWLOX FOR DETAILS *
* MARINE WEATHER STATEMENT...SEE FZUS76 KLOX - MWSLOX FOR DETAILS *
* SPECIAL WEATHER STATEMENT..SEE WWUS86 KLOX - SPSLOX FOR DETAILS *
.SPOTTER INFORMATION STATEMENT...
WEATHER SPOTTERS ARE ENCOURAGED TO REPORT SIGNIFICANT WEATHER
CONDITIONS ACCORDING TO STANDARD OPERATING PROCEDURES.
SPECIAL WEATHER STATEMENT
Issue Date: 241 PM PST SAT DEC 5 2009
Expiration: 600 AM PST SUN DEC 06 2009
...POTENTIAL FOR SIGNIFICANT RAIN AND MOUNTAIN SNOW MONDAY FOLLOWED
BY COLD TEMPERATURES AND POTENTIAL FROST FOR MANY AREAS MONDAY NIGHT...
...POTENTIAL FOR ADDITIONAL STORMS TO AFFECT SOUTHERN AND CENTRAL
CALIFORNIA LATER NEXT WEEK...
A SERIES OF PACIFIC STORMS ARE EXPECTED TO MOVE INTO CALIFORNIA
NEXT WEEK...BRINGING PERIODS OF RAIN AND MOUNTAIN SNOW TO THE
STATE.
A COLD UPPER LEVEL LOW PRESSURE SYSTEM WILL DEVELOP ACROSS OREGON
AND NORTHERN CALIFORNIA ON SUNDAY. AS THE SYSTEM DIGS SOUTH...AN
INCREASING CHANCE FOR RAIN AND MOUNTAIN SNOW WILL OCCUR ACROSS THE
REGION LATE SUNDAY NIGHT...WITH PRECIPITATION OVERSPREADING THE
ENTIRE FORECAST AREA ON MONDAY.
THIS FIRST STORM SYSTEM IS NOW TAKING A MORE OVER-WATER TRAJECTORY.
DUE TO MORE AVAILABLE MOISTURE...PRECIPITATION AMOUNTS HAVE
BEEN INCREASED FROM EARLIER FORECASTS. RAINFALL ESTIMATES WITH THIS
SYSTEM ARE NOW EXPECTED TO RANGE BETWEEN .50 AND 1.50 INCHES
ACROSS MOST AREAS...WITH 1.50 TO 3.00 INCHES EXPECTED ACROSS SOUTH
AND SOUTHWEST FACING FOOTHILL AND MOUNTAIN LOCATIONS. THE HIGHEST
RAINFALL AMOUNTS ARE EXPECTED ACROSS LOS ANGELES COUNTY...ESPECIALLY
ACROSS THE SAN GABRIEL MOUNTAINS AND ADJACENT FOOTHILLS.
THE GREATEST THREAT OF PRECIPITATION FOR THE STATION FIRE BURN AREA
WILL BE LATE MONDAY MORNING THROUGH EARLY MONDAY EVENING. DURING THIS
TIME...THERE WILL LIKELY BE PERIODS OF MODERATE RAIN...WITH THE POTENTIAL
FOR OCCASIONAL HEAVY RAINFALL. RAINFALL RATES ACROSS THE STATION
BURN AREA ARE GENERALLY EXPECTED TO RANGE BETWEEN ONE QUARTER AND
ONE THIRD OF AN INCH PER HOUR FROM LATE MONDAY MORNING THROUGH EARLY
MONDAY EVENING. HOWEVER...SINCE THE AIR MASS WILL BE COLD AND SLIGHTLY
UNSTABLE...THERE WILL BE THE POTENTIAL FOR BRIEF HEAVY SHOWERS...WHERE
RAINFALL RATES COULD REACH AS HIGH AS ONE HALF INCH PER HOUR MONDAY
AFTERNOON INTO EARLY MONDAY EVENING ACROSS THE STATION FIRE BURN AREA.
THE INCREASED THREAT OF HIGHER RAINFALL AMOUNTS AND INTENSITIES WILL BRING
GREATER CONCERN FOR THE POTENTIAL FOR DEBRIS FLOWS IN RECENT BURN AREAS...
INCLUDING THE STATION FIRE BURN AREA. AS WE DRAW CLOSER TO THE EVENT...A
FLASH FLOOD WATCH MAY NEED TO BE ISSUED FOR THE RECENT BURN AREAS.
THIS STORM WILL ALSO BRING THE POTENTIAL FOR SIGNIFICANT SNOW AND
STRONG WINDS ACROSS HIGHER MOUNTAIN ELEVATIONS. BEHIND THE FRONT...
SNOW LEVELS WILL FALL RAPIDLY MONDAY NIGHT AS VERY COLD AIR
SPREADS ACROSS THE REGION. LATER MONDAY NIGHT...SNOW LEVELS COULD FALL
AS LOW AS 2000 FEET...BRINGING THE POTENTIAL FOR SNOW SHOWERS
ACROSS THE ANTELOPE VALLEY...CUYAMA VALLEY...AND MUCH OF THE INTERSTATE
5 CORRIDOR NORTH OF CASTAIC. THE VERY COLD AIR MASS WILL LIKELY CREATE
DANGEROUS ICY CONDITIONS IN THE MOUNTAINS...ALONG WITH THE POTENTIAL FOR
AREAS OF FROST IN LOCATIONS FREE FROM PRECIPITATION AND WINDS. FOR MORE
INFORMATION ON WINTER WEATHER CONDITIONS...PLEASE REFER TO THE LATEST
WINTER STORM WATCH PRODUCT.
LATER IN THE WEEK...A SECOND STORM WILL LIKELY IMPACT SOUTHERN AND
CENTRAL CALIFORNIA LATE WEDNESDAY INTO THURSDAY. DUE TO THIS SYSTEMS
SUBTROPICAL COMPONENT...THIS SYSTEM COULD BE MORE POWERFUL...
WARMER...AND BE A MORE EFFICIENT RAIN MAKER. HOWEVER...THERE STILL
EXISTS SOME UNCERTAINTY IN THE EXACT TIMING AND PLACEMENT OF HEAVIER
RAINFALL ACROSS THE AREA. SINCE THIS STORM WILL LIKELY HAVE A GREATER
PRECIPITATION DURATION AND INTENSITY...RESIDENTS AND LOCAL EMERGENCY
OFFICIALS ARE URGED TO STAY TUNED TO THE LATEST NATIONAL WEATHER
SERVICE FORECASTS FOR UPDATES ON THIS DEVELOPING WEATHER SITUATION.
A THIRD SYSTEM REMAINS A POSSIBILITY FOR LATE NEXT WEEK...POSSIBLY
BRINGING ADDITIONAL PRECIPITATION TO THE REGION.
THESE STORMS WILL LIKELY GENERATE LARGE SWELLS AND HIGH SURF
CONDITIONS AT TIMES NEXT WEEK. PLEASE REFER TO THE LATEST MARINE WEATHER
STATEMENT FOR THE LATEST DETAILS ACROSS THE COASTAL WATERS.
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