Small Craft Advisory 15, NWS Eureka, CA

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE EUREKA CA
200 PM PST THU FEB 25 2010

.SYNOPSIS...A STRONG STORM WILL BRING HEAVY RAINS AND HIGH
ELEVATION SNOW TO NORTHWEST CALIFORNIA LATE TONIGHT THROUGH
FRIDAY NIGHT.

&&

.DISCUSSION...RADAR SHOWED A BAND OF LIGHT RAIN SHOWERS MOVING
ACROSS THE NORTHERN PORTION OF THE FORECAST AREA THIS AFTERNOON.
THESE SHOWERS HAVE PRODUCED ONLY A FEW HUNDREDTHS OF AN INCH OF
RAIN. SATELLITE IMAGERY SHOWED THE MAIN BRUNT OF THE INCOMING
STORM WEST OF 130W AS OF 200 PM. THE MAJORITY OF THE MODELS HAVE
COME INTO AGREEMENT WITH THE POSITION OF THE LOW AND THE TIMING OF
MAX PRECIP. THE SLOW EASTWARD MOVEMENT OF THE LOW COUPLED WITH A
SUBTROPICAL MOISTURE PLUME WILL RESULT IN MODERATE TO HEAVY
RAIN...LATE TONIGHT THROUGH FRIDAY. FROM LATE TONIGHT THROUGH FRI
EXPECT TOTAL RAINFALL AMOUNTS OF 1-3 INCHES ACROSS THE ENTIRE
AREA...WITH WETTER SPOTS IN THE KING RANGE AND IN DEL NORTE
COUNTY RECEIVING UP TO 5 INCHES.

MAIN FORECAST CHALLENGE CONTINUES TO BE SNOW LEVELS. MODELS SHOW
THAT SNOW LEVELS WILL RISE AS WARM/MOIST AIR SPREADS INTO THE AREA
AHEAD OF A WARM FRONT TONIGHT. SNOW LEVELS SHOULD FALL ON FRIDAY
AFTER A COLD FRONT MOVES THROUGH IN THE AFTERNOON. LATEST SURFACE
OBSERVATIONS SUPPORT SNOW FALL ABOVE 4500 TO 5000 FEET
TONIGHT...WITH DEW POINT ONLY IN THE MID TO UPPER 30S. WE DID GO
FORWARD WITH A HEAVY SNOW WARNING ABOVE 4000-5000 FEET LATE
TONIGHT THROUGH FRIDAY. COLD TRAPPED AIR AND HEAVY PRECIP RATES
IN NORTHEASTERN TRINITY MAY ALSO RESULT IN SNOW DOWN TO 2500 TO
3500 FEET ON FRIDAY. HOWEVER...IT APPEARS SIGNIFICANT SNOWFALL
WILL BE ABOVE 4500 TO 5000 FEET.

FOR THE EXTENDED...A RIDGE LOOKS TO BUILD SAT NIGHT INTO SUNDAY
AND SHOULD HOLD THROUGH MONDAY FOR DRY AND STABLE WEATHER. A NEW
SYSTEM APPROACHES EARLY NEXT WEEK FOR ANOTHER CHANCE OF RAIN.
TIMING OF THIS TROUGH IS STILL UNCERTAIN AND THE RAIN MAY LINGER
INTO WED. THUS MAINTAINED A NEAR CLIMO FORECAST...EVEN THOUGH 12Z
GFS INDICATES A RIDGE BUILDING ON WED. DJB

&&

.AVIATION...A STRONG STORM SYSTEM WILL MOVE THROUGH THE REGION
TONIGHT AND FRIDAY. SOUTHERLY WINDS WILL CONTINUE TO INCREASE AND
BECOME GUSTY THIS LATE AFTERNOON AND EVENING. NON-CONVECTIVE LLWS
WILL BE LIKELY TONIGHT AS A STRONG LOW LEVEL JET MOVES INTO THE
AREA. CONDITIONS WILL DETERIORATE TO PREVAILING MVFR WITH AREAS OF
IFR CONDITIONS IN THE HEAVIER PRECIPITATION (SNOW IN HIGHER
ELEVATIONS) OVERNIGHT TONIGHT AND FRIDAY MORNING. HENRY

&&

.MARINE...SOUTHERLY WINDS WILL CONTINUE TO INCREASE RAPIDLY THIS
LATE AFTERNOON AND EVENING. GALE FORCE WINDS WILL AFFECT THE
NORTHERN AND NORTHERN PORTION OF THE SOUTHERN OUTER WATERS...AND
GALE FORCE GUSTS ARE EXPECTED ALONG THE COAST THROUGH EARLY FRIDAY.
WIND WAVES WILL ALSO BUILD RAPIDLY...MAKING SEAS VERY HAZARDOUS THIS
LATE AFTERNOON THROUGH EARLY FRIDAY. A GALE AND HAZARDOUS SEAS
WARNING ARE IN EFFECT ACCORDINGLY. WINDS WILL DIMINISH
FRIDAY...MAINLY IN THE AFTERNOON...BUT REMAIN ABOVE SMALL CRAFT
ADVISORY CRITERIA. THE ASSOCIATED LARGE WSW SWELL OF 16 TO 17 FEET
AROUND 15 SECONDS IS STILL PROGGED TO REACH OUR WATERS SATURDAY.
THIS SWELL WILL RESULT IN HIGH SURF ALONG THE COAST...BUT BREAKERS
ARE EXPECTED TO REMAIN UNDER ADVISORY LEVELS. ANOTHER LARGE WESTERLY
SWELL AROUND 16 FT IS EXPECTED TO BUILD INTO THE WATERS BY TUESDAY.
HENRY

&&

.EKA WATCHES/WARNINGS/ADVISORIES...WINTER STORM WARNING FROM 3 AM
TO 11 PM PST FRIDAY ABOVE 4000 FEET FOR THE CAZ004. SMALL CRAFT
ADVISORY UNTIL 4 PM PST THIS AFTERNOON PZZ450-455-470-475. GALE
WARNING UNTIL 6 AM PST FRIDAY PZZ450-455-470-475. HAZARDOUS SEAS
WARNING UNTIL 6 AM PST FRIDAY PZZ450-455-470-475.

&&

VISIT US AT HTTP://WWW.WEATHER.GOV/EUREKA

HAZARDOUS WEATHER OUTLOOK...UPDATED
NATIONAL WEATHER SERVICE EUREKA CA
258 PM PST THU FEB 25 2010

CAZ001>003-076-261430-
REDWOOD COAST-MENDOCINO COAST-NORTH COAST INTERIOR-
MENDOCINO INTERIOR-
258 PM PST THU FEB 25 2010

THIS HAZARDOUS WEATHER OUTLOOK IS FOR NORTHWEST CALIFORNIA.

.DAY ONE...THIS AFTERNOON AND TONIGHT.

A STRONG STORM WILL BRING A WIDESPREAD 1 TO 3 INCHES OF RAIN AND
HIGHER ELEVATION SNOW TONIGHT AND FRIDAY. RAINFALL TOTALS UP TO 5
INCHES WILL BE POSSIBLE IN FAVORED LOCATIONS SUCH AS KING RANGE.
LOCALIZED MINOR FLOODING AND PONDING OF WATER WILL BE
POSSIBLE...ESPECIALLY IN LOW LYING AREAS.

FOR FURTHER DETAILS PLEASE REFER TO NOAA WEATHER RADIO OR
WEATHER.GOV/EUREKA.

.DAYS TWO THROUGH SEVEN...FRIDAY THROUGH WEDNESDAY.

A STRONG STORM WILL CONTINUE TO BRING PERIODS OF HEAVY RAIN AND
HIGHER ELEVATION SNOW FRIDAY. LOCALIZED MINOR FLOODING
AND PONDING OF WATER WILL BE POSSIBLE...ESPECIALLY IN LOW LYING
AREAS.

THE COMBINATION OF THE STORM SURGE AND HIGH TIDE WILL RESULT IN
MINOR FLOODING ACROSS THE KING SALMON AREA LATE FRIDAY MORNING.

PLEASE STAY TUNED TO THE LATEST FORECASTS FOR UPDATES ON THIS
DEVELOPING SITUATION.

.SPOTTER INFORMATION STATEMENT...
SPOTTERS ARE ENCOURAGED TO REPORT SIGNIFICANT WEATHER TO THE
NATIONAL WEATHER SERVICE IN EUREKA.

CAZ004-261430-
UPPER TRINITY RIVER-
258 PM PST THU FEB 25 2010

...WINTER STORM WARNING IN EFFECT FROM 3 AM TO 11 PM PST FRIDAY...

THIS HAZARDOUS WEATHER OUTLOOK IS FOR NORTHWEST CALIFORNIA.

.DAY ONE...THIS AFTERNOON AND TONIGHT.

A WINTER STORM WARNING ABOVE 4000 FEET IS CURRENTLY IN EFFECT.

FOR FURTHER DETAILS PLEASE REFER TO NOAA WEATHER RADIO OR
WEATHER.GOV/EUREKA.

.DAYS TWO THROUGH SEVEN...FRIDAY THROUGH WEDNESDAY.

A WINTER STORM WARNING ABOVE 4000 FEET IS CURRENTLY IN EFFECT.

FOR FURTHER DETAILS PLEASE REFER TO NOAA WEATHER RADIO OR
WEATHER.GOV/EUREKA.

.SPOTTER INFORMATION STATEMENT...
SPOTTERS ARE ENCOURAGED TO REPORT SNOW ACCUMULATIONS AND TOTALS TO
THE NATIONAL WEATHER SERVICE IN EUREKA.