Hazardous Seas Warning 31, NWS Eureka, CA

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE EUREKA CA
500 AM PDT THU OCT 2 2008

.SYNOPSIS...A WEAKENING LOW PRESSURE SYSTEM WILL BRING LIGHT RAIN TO
COASTAL AREAS OF NORTHERN CALIFORNIA TODAY  ANOTHER WAVE OF LOW
PRESSURE ON THE HEELS ON THIS SYSTEM...WILL BRING MORE SIGNIFICANT
RAINFALL AND COOLING TO ALL OF NORTHERN CALIFORNIA FRIDAY AFTERNOON
THROUGH SATURDAY. A DRYING TREND WILL FOLLOW SUNDAY THROUGH MUCH OF
TUESDAY...WITH A CHANCE OF RAIN ARRIVING BY THE MIDDLE OF NEXT WEEK.

&&

.SHORT TERM...TODAY THROUGH SATURDAY...RADAR IMAGERY IS SHOWING SOME
WEAK RETURNS ASSOCIATED WITH WHAT APPEARS TO BE THE FINAL SIGNIFICANT
PRECIP BAND ASSOCIATED WITH LAST NIGHTS FRONTAL PASSAGE. AT THIS TIME
NO MEASURABLE RAIN WAS RECORDED AT WOODLEY ISLAND HOWEVER 0.15 INCHES
FELL AT CRECSENT CITY WHILE UKIAH REPORTED A FEW HUNDRETHS. BASED ON
CURRENT RADAR IMAGERY ANOTHER .05 INCHES IS POSSIBLE OVER THE NEXT
HOUR.  TEMPERATURES WILL BE ABOUT 10-15 DEGREES COOLER INLAND ON
TODAY AS THE CLOUDS AND RAIN MOVE THROUGH. THE RAIN FROM THIS
FIRST SYSTEM IS EXPECTED TO STICK AROUND THROUGH THURSDAY. AFTER A
SHORT BREAK...RAIN FROM A SECOND...MUCH STRONGER SYSTEM WILL MOVE
THROUGH FROM FRIDAY THROUGH SATURDAY NIGHT. THIS SYSTEM IS MUCH MORE
POTENT WITH ITS MOISTURE AND UPPER LEVEL SUPPORT. THE ENTIRE AREA
WILL LIKELY RECEIVE WETTING RAINS...WITH NORTHERNMOST SECTIONS
EASILY SEEING OVER AN INCH.

&&

.PREV LONG TERM...SUNDAY THROUGH WEDNESDAY...CONSENSUS IS GOOD THAT
A SHARP AMPLITUDE BUT STEADILY PROGRESSIVE SHORT-WAVE RIDGE WILL
APPROACH...THEN TRAVERSE NRN CALIFORNIA SUNDAY THROUGH TUESDAY.
RESULTANT SENSIBLE WEATHER SHOULD BRING A DRYING PERIOD AND A
DAYTIME WARMING TREND LATE WEEKEND INTO EARLY NEXT WEEK. COOLISH
MORNING LOWS WILL REFLECT AUTUMN COUPLED WITH TRAPPED PATCHY FOG IN
COASTAL VALLEYS. LATE TUESDAY INTO WEDNESDAY BRINGS A PATTERN CHANGE
TOWARD WETTER COOLER AS BOTH GFS AND ECMWF DEPICT AN UPPER TROUGH
MOVING INTO THE PACIFIC NW. AFTER A FEW DAYS BREAK FROM RAIN...THIS
PACKAGE WE ADVERTISE A SLIGHT CHANCE LATE TUESDAY THROUGH WEDNESDAY.
COLBY

&&

.AVIATION...A COLD FRONT WILL BRING MID LEVEL CLOUDS AND LIGHT RAIN
ACROSS THE REGION THIS MORNING...WITH ISOLATED TO SCATTERED
POST-FRONTAL SHOWERS IN THE AFTERNOON. FLIGHT CONDITIONS WILL REMAIN
MVFR TO VFR TODAY. TH

&&

.MARINE...A COLD FRONT WILL CONTINUE TO PUSH THROUGH THE WATERS THIS
MORNING. THE WEST SWELL THAT IS CURRENTLY PROPAGATING THROUGH THE
WATERS WILL SUBSIDE THURSDAY NIGHT AND FRIDAY. SOUTHERLY WINDS WILL
INCREASE FRIDAY MORNING AHEAD OF THE NEXT FRONT...WITH MARGINAL
GALES BY FRIDAY AFTERNOON. THE 00Z MODELS HAVE BACKED OFF ON THE
STRENGTH OF THE FRONT AND CONFIDENCE WAS NOT HIGH ENOUGH TO UPGRADE
THE WATCHES TO WARNINGS FOR THIS FORECAST PACKAGE. THE BIG STORY
WITH THIS STORM IS THE LARGE NW SWELL THAT WILL PROPAGATE THROUGH
THE WATERS OVER THE WEEKEND. ENP IS FORECASTING WAVE HEIGHTS UP TO
20 FT ACROSS THE NORTHERN WATERS SATURDAY. HAVE WENT 3 TO 5 FT BELOW
GUIDANCE SINCE THE WAVE MODELS TEND TO OVERFORECAST BUILDING NW
SWELLS. HAVE EXTENDED THE HAZARDOUS SEAS WATCH THROUGH SUNDAY TO
ACCOUNT FOR THIS LARGE SWELL. TH

&&

.EKA WATCHES/WARNINGS/ADVISORIES...
SCA FOR SEAS FROM PT ST GEORGE TO PT ARENA OUT 10NM.

SCA FOR WINDS AND SEAS FROM PT ST GEORGE TO PT ARENA 10 TO 60 NM.

GALE WATCH FRIDAY AFTERNOON THROUGH SATURDAY MORNING FROM PT ST
GEORGE TO CAPE MENDOCINO OUT 10 NM.

GALE WATCH FRIDAY AFTERNOON THROUGH SATURDAY MORNING FROM PT ST
GEORGE TO PT ARENA 10 TO 60 NM.

HAZARDOUS SEAS WATCH FRIDAY EVENING THROUGH SUNDAY EVENING FROM PT
ST GEORGE TO CAPE MENDOCINO OUT 60 NM.

HAZARDOUS SEAS WATCH SATURDAY MORNING THROUGH SUNDAY EVENING FROM
CAPE MENDOCINO TO PT ARENA OUT 60 NM.

&&

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