Small Craft Advisory 34, NWS Juneau, AK

SOUTHEAST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE JUNEAU AK
238 PM AKST MON JAN 10 2011

.SHORT TERM...MASSIVE UPPER HIGH WILL REMAIN OVER NW AK THRU
TUE. A MID-LEVEL SHORTWAVE TROF OVER THE YUKON WILL DROP SSW THRU
THE AREA LATE TONIGHT. A SFC HIGH OVER NW CANADA WILL WEAKEN SOME
TONIGHT...THEN STRENGTHEN TUE.

MAIN FORECAST CONCERN THRU TUE WILL BE WINDS. ATTM THE PRES
GRADIENTS ARE SLOWLY WEAKENING DUE TO THE WEAKENING OF THE NW
CANADA HIGH. THIS WILL CAUSE WINDS TO GENERALLY DECREASE SOME
ACROSS THE AREA TONIGHT. ONCE THE SHORTWAVE DROPS S OF THE AREA
THOUGH TOWARD DAYBREAK TUE...THE SFC HIGH WILL REBUILD AND
GRADIENTS WILL INCREASE THRU THE DAY TUE. TIMING ONSET OF
POTENTIAL ADVY LEVEL WINDS WILL BE TRICKY BUT BASED ON LOCAL RULES
IT LOOKS LIKE THE PAGY AND PAYA OUTFLOW AREAS WILL START UP AROUND
18Z TUE. WILL ISSUE WIND ADVYS FOR THOSE AREAS WITH THIS PACKAGE.
ELSEWHERE...IT LOOKS LIKE ANY ADVY LEVEL WINDS WILL HOLD OFF UNTIL
00Z WED AT LEAST...ALTHOUGH THE PAJN LOCAL AREA MAY START SLIGHTLY
BEFORE THEN BUT WILL NOT ISSUE ONE THERE AS IT LOOKS LIKE
POTENTIAL WARNING LEVEL TAKU WIND EVENT STARTING TUE NIGHT. WILL
SEE GALES DEVELOP OVER THE LYNN CANAL AND GLACIER BAY AREAS
TUE...WITH GALE FORCE OUTFLOW INTO THE NE GULF AREA. MUCH OF THE
REMAINING AREAS SHOULD SEE SCA LEVEL WINDS ESPECIALLY TUE.

OTHERWISE...WITH UPSLOPE NLY FLOW ON CANADIAN SIDE AND SHORTWAVE
DROPPING SWD TONIGHT...THERE WILL BE MID-LEVEL CLOUDS OVER THE FAR
NRN AREA. THEY WILL TEND TO THIN OUT AS THEY MOVE SWD HOWEVER.
WILL GO WITH MOSTLY CLOUDY FOR THE PAHN/PAGY AREAS...AND PARTLY
CLOUDY FOR THE REMAINING NRN ZONES FOR TONIGHT AND TUE. SRN AREAS
MAY SEE SOME CLOUDS APPROACH FROM THE EAST BUT THEY SHOULD TEND TO
BREAK UP AS THEY ENTER THE HYDER ZONE. WILL GO PARTLY CLOUDY FOR
HYDER...AND MOSTLY CLEAR FOR THE REMAINDER OF THE SRN AREA TONIGHT
AND TUE.

TEMPS WILL BE TRICKY AS WELL. EXPECT WHERE WINDS REMAIN UP THAT
TEMPS WILL REMAIN ABOVE MOS GUIDANCE...WHILE IN WIND SHELTERED
AREAS THEY WILL LIKELY BE COLDER THAN MOS. MORE WIDESPREAD WINDS
SHOULD DEVELOP TUE AS COLD ADVECTION COMMENCES ESPECIALLY TUE
AFTERNOON...SO THERE WILL LIKELY BE LESS VARIABILITY WITHIN ANY
GIVEN ZONE. EXPECT MAX TEMPS TUE TO BE ONLY A COUPLE DEGREES
COLDER THAN TODAY ON AVERAGE. TEMPS OVER THE WATER LOOK TOO WARM
FOR FREEZING SPRAY UNTIL TUE OVER NRN LYNN CANAL...AND EVEN THEY
WILL BE BORDERLINE. WILL HAVE LIGHT FREEZING SPRAY OVER NRN LYNN
CANAL TUE...AND TAKE MENTION OUT ELSEWHERE FOR TONIGHT AND TUE.

&&

.LONG TERM...BLOCKING RIDGE EXPECTED TO PERSIST OVER NORTHWEST
PORTION OF THE STATE. AT MID LEVELS A WEAK TROUGH WILL ESTABLISH
ITS SELF OVER THE PANHANDLE THROUGH MID WEEK. THIS WILL RESULT IN
A WEAK OR NULL FLOW ALOFT THAT THAT WILL BE THE CRITICAL LAYER
LAYER ALOFT NEEDED FOR A TAKU WIND EVENT FORMATION. HIGH PRESSURE
OVER NORTHWEST ALASKA WILL CONTINUE TO INCREASE AND TIGHTEN
PRESSURE GRADIENTS FOR OUTFLOW WINDS AND STRONG WINDS OVER THE
NORTHERN INNER CHANNELS. LOOKING FOR STORM FORCE TO STRONG GALE
FORCE FOR MARIN AREAS. GUSTS OVER LAND AREAS TO 45 TO 55 MPH AT
TIMES AS WELL DEPENDING ON LOCATION.

LOOK FOR A COOL DOWN IN THE TEMPERATURES AS WELL...THIS COULD LEAD
TO SOME LOCAL AREAS OF WINDS CHILL NEAR ADVISORY LEVELS STARTING
TUESDAY NIGHT ACROSS THE NORTHERN PORTIONS OF THE PANHANDLE.

ADJUSTMENTS TO THE FORECAST WERE MADE WITH NAM AND HPC SOLUTION AT
THE LATER PERIODS FOR WINDS. CONFIDENCE IS AVERAGE OR SLIGHTLY
BETTER LEADING INTO THE WEEKEND AND AVERAGE OR LESS.

.AJK WATCHES/WARNINGS/ADVISORIES...
PUBLIC...WIND ADVISORY FROM 3 PM TUESDAY TO 3 AM AKST WEDNESDAY FOR
     AKZ019-025.
         WIND ADVISORY FROM 6 PM TUESDAY TO 3 AM AKST WEDNESDAY FOR
     AKZ020-022.
         WIND ADVISORY FROM 9 AM TUESDAY TO 3 AM AKST WEDNESDAY FOR
     AKZ017-018.
MARINE...HEAVY FREEZING SPRAY WARNING FOR PKZ011-012.
         GALE WARNING FOR PKZ011>013-051-052.
         SMALL CRAFT ADVISORY FOR PKZ021-022-031>036-043.
         SMALL CRAFT ADVISORY DUE TO SEAS FOR PKZ041.

&&

RWT/BEZENEK