Gale Warning 140, NWS Juneau, AK

SOUTHEAST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE JUNEAU AK
224 PM AKDT WED MAR 11 2009

.SHORT TERM... THE WEAK TROF THAT HAS BEEN HANGING AROUND THE N
GULF THE LAST COUPLE OF DAYS WILL DISSIPATE LATER THIS EVENING. A
LOW WILL DEVELOP OVER THE NE PAC TONIGHT AND MOVE N INTO THE NE
GULF THU AFTERNOON.

 MAIN CONCERN REMAINS WHEN WILL SNOW TURN OVER TO RAIN. LATEST
MODELS TREND THE DEVELOPING N PAC LOW TOWARDS THE EAST WHICH
WOULD SLOW THE ARRIVAL OF THE WARMER AIR. EXPECT DEW POINT VALUES
TO START RISING ALONG THE SOUTHERN OUTER COAST LATE THIS
AFTERNOON AND GRADUALLY PROGRESS NORTHWARD THROUGH THE EVENING.
EXPECT SNOW TO CONTINUE THROUGH NORTH OF FREDRICK SOUND THROUGH
EARLY THU MORNING WITH SNOW BEGINNING TO MIX WITH RAIN ALONG A
PAEL/PAJN LINE THROUGH THE LATE MORNING HOURS. PAGY/PAHN WILL
REMAIN THROUGH THU AFTERNOON BEFORE THE WARMER AIR REACHES THEM.

 ISSUED SNOW ADVISORY FOR AKZ028 UNTIL 6 PM TONIGHT AS 2 INCHES
HAD BEEN REPORTED IN THORNE BAY AND SNOW WAS STILL CONTINUING TO
COME AT A MODERATE PACE. ALL OTHER WSW STATEMENTS WERE LEFT
UNCHANGED. WITH EASTERLY WIND...FELT ELFIN COVE/PELICAN POSSIBLY
SEE SNOW ADVISORY LEVELS TONIGHT BUT LEFT AMOUNTS JUST UNDER
CRITERIA BUT WARM AIR EXPECTED TO MOVE IN EARLY THU MORNING
BEFORE CRITERIA CAN BE REACHED. FINALLY...PAYA MAY NEED A SNOW
ADVISORY FOR TOMORROW IF LOW TRACK CONTINUES TO SHIFT TO THE
EAST. WILL WAIT FOR THE NEXT SET OF MODEL RUNS TO COME IN AND LET
FUTURE SHIFTS MAKE THAT DECISION.

 AS FOR WINDS...EXPECT SCA IN E-W INNER CHANNELS AND ALONG OUTER
COAST THIS EVENING. AS LOW DRAWS CLOSER...WINDS WILL INCREASE TO
GALES IN CROSS SOUND AND ICY STRAIT. KEPT N-S CHANNELS JUST BELOW
SCA THOUGH THAT MAY NEED TO BE AMENDED LATER TONIGHT/EARLY THU
MORNING. ISSUED WIND ADVISORY FOR AKZ023-027 BEGINNING 5 AM THU
AND AKZ022 BEGINNING AT 9 AM. SOUTHEASTERLY WINDS WITH GUSTS TO
40 MPH EXPECTED TO CONTINUE THROUGH THU AFTERNOON THEN DIMINISH
AFTER LANDFALL NEAR CAPE FAIRWEATHER.

.LONG TERM...LONG RANGE PERIOD BEGINS WITH THE LOW DISCUSSED ABOVE
LOCATED IN THE NORTHEAST GULF. LOW LEVEL SOUTHWEST WINDS
PRODUCING WIND ADVISORIES FOR THE CENTRAL OUTER COAST. THE BIGGEST
QUESTION EARLY ON IN THE EXTENDED RANGE FORECAST HAS BEEN WHETHER
THE LOW WILL COME ASHORE NORTH OR SOUTH OF CAPE FAIRWEATHER. THE
00Z ECMWF ALONG WITH THE 12Z UKMET HAD THE SYSTEM WELL TO THE WEST
WHILE OTHERS WERE MORE TO THE EAST. BASED ON UPPER LEVEL JET
SUPPORT AND STEERING...BELIEVE THE MORE EASTERLY TRACK TO BE MORE
PROBABLE. THE 12Z ECMWF IS MORE EASTERLY IN ITS TRACK AS WELL AS
SLOWER AND A LITTLE DEEPER...BUT IS STILL ONE OF THE MORE WESTERLY
SOLUTIONS. LANDFALL WILL HAPPEN EARLY IN THE LONG RANGE FORECAST
SOMETIME THURSDAY NIGHT AND SOON THEREAFTER ADVISORY LEVEL WINDS
ALONG THE OUTER COAST WILL CEASE. CURRENTLY HAVE A WIND ADVISORY
THAT BEGINS IN THE SHORT RANGE AND ENDS AT 3 AM FRIDAY MORNING FOR
ZONES 22 AND 23. FORECAST CONFIDENCE ABOVE AVERAGE THROUGH
THURSDAY NIGHT.

AFTERWARDS...NOT A LOT OF ACTIVITY IN THE EXTENDED RANGE FORECAST
UNTIL LATE IN THE WEEKEND WHEN MODELS ARE BEGINNING TO SUGGEST A
POTENTIALLY STRONG LOW APPROACHING THE SOUTHERN OUTER COAST SUNDAY
AFTERNOON/EVENING. MODEL SPREAD CURRENTLY VERY LARGE ON THIS
SYSTEM FOR PRESSURE...SURFACE WINDS...AND LOW LEVEL TEMPERATURES.
PRECIP FIELDS...HOWEVER...ARE IN FAIRLY GOOD AGREEMENT. SO WHILE
FORECAST CONFIDENCE IN THE STRENGTH OF THIS SYSTEM AND THE TYPE OF
PRECIP ASSOCIATED IS BELOW AVERAGE...CONFIDENCE IS HIGH THAT IT
WILL BRING MORE PRECIPITATION TO PRIMARILY THE SOUTHERN HALF OF
THE PANHANDLE.

.AJK WATCHES/WARNINGS/ADVISORIES...
PUBLIC...WIND ADVISORY FROM 5 AM TO 3 PM AKDT THURSDAY FOR AKZ027.
WIND ADVISORY FROM 5 AM THURSDAY TO 3 AM AKDT FRIDAY FOR AKZ023.
WIND ADVISORY FROM 12 PM THURSDAY TO 3 AM AKDT FRIDAY FOR AKZ022.
WINTER WEATHER ADVISORY FROM 6 PM THIS EVENING TO 6 AM AKDT THURSDAY
FOR AKZ020-021-025.
WINTER WEATHER ADVISORY UNTIL 6 PM AKDT THIS AFTERNOON FOR AKZ028.
WINTER WEATHER ADVISORY FROM MIDNIGHT TONIGHT TO 12 PM AKDT THURSDAY
FOR AKZ018.
WINTER STORM WARNING FROM MIDNIGHT TONIGHT TO 12 PM AKDT THURSDAY
FOR AKZ019.

MARINE...GALE WARNING FOR PKZ021-022-036.
	 SMALL CRAFT ADVISORY FOR PKZ011>013-031>035-041>043-051-052.

&&

MAM/FRITSCH