Gale Warning 433, NWS Juneau, AK

889 
FZAK67 PAJK 171227
OFFAJK

OFFSHORE WATERS FORECAST
NATIONAL WEATHER SERVICE JUNEAU AK
400 AM AKST MON DEC 17 2012 

OFFSHORE WATERS FORECAST FOR GULF OF ALASKA EAST OF 144W

WIND FORECASTS REFLECT THE PREDOMINANT SPEED AND DIRECTION
EXPECTED. SEA FORECASTS REPRESENT THE AVERAGE OF THE HIGHEST
ONE-THIRD OF THE COMBINED WINDWAVE AND SWELL HEIGHT.

PKZ398-180100-
400 AM AKST MON DEC 17 2012 
.SYNOPSIS FOR THE EASTERN GULF OF ALASKA...
A 988 MB LOW OVER THE EASTERN GULF WILL SLOWLY WEAKEN AS IT
DRIFTS SOUTHEAST THROUGH MON. ARCTIC HIGH PRESSURE IN THE
ALASKAN INTERIOR AND YUKON TERRITORY WILL BUILD INTO THE
NORTHERN PANHANDLE THROUGH MON. ANOTHER LOW WILL MOVE INTO THE
GULF TUE. 

$$

PKZ310-180100-
GULF OF ALASKA NORTH OF 55 DEGREES NORTH AND EAST OF 144 DEGREES
WEST-
400 AM AKST MON DEC 17 2012 

...GALE WARNING THROUGH TODAY...

.TODAY...NW WIND 35 KT DIMINISHING TO 25 KT IN THE AFTERNOON.
SEAS 13 FT. RAIN SHOWERS IN THE MORNING.
.TONIGHT...W WIND 20 KT BECOMING S LATE. SEAS 10 FT. W SWELL.
.TUE...SE WIND 25 KT INCREASING TO GALE TO 40 KT IN THE AFTERNOON.
SEAS BUILDING TO 14 FT. RAIN AND SNOW.
.TUE NIGHT...SE GALE TO 40 KT. SEAS 17 FT. RAIN.
.WED...NE GALE TO 35 KT. SEAS 18 FT. SNOW...THEN RAIN. 
.THU...NE WIND 20 KT. SEAS 9 FT. 
.FRI...NE WIND 15 KT. SEAS 6 FT. 

$$

SOUTHEAST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE JUNEAU AK
257 PM AKST SUN DEC 16 2012

.SHORT TERM...A 985 MB LOW ABOUT 120 NM S OF YAKUTAT IS MOVING
SE AND SHOULD BE ABOUT 120 NM SSW OF KETCHIKAN AT 00Z TUE. THIS
TRACK WILL WILL BE PARTIALLY DUE TO INTERACTION WITH A ZONALLY
TRACKING POLAR FRONT ZONE WAVE THAT IS TO MOVE ONSHORE NEAR
SEATTLE TONIGHT.

 THE ARCTIC OUTBREAK ALREADY IN THE NORTHERN PANHANDLE WILL
RAPIDLY SPREAD S ALONG THE PANHANDLE AS THERE WILL BE A NORTHERLY
GRADIENT SUPPORTED BY A COMBINATION OF THE ARCTIC HIGH IN YUKON
TERRITORY AND THE LOW TO THE SOUTH.

 CONFIDENCE IS AVERAGE. PLEASE NOTE THE ARCTIC OUTBREAK WILL ALSO
PROVIDE FREEZING SPRAY IN THE NORTHERN INNER CHANNELS AND BY MON
NIGHT WILL ALSO COME OUT OF INTERIOR PASSES INTO STEPHENS
PASSAGE.

 THE MODEL CONSENSUS HAS BEEN USEFUL.  AT THE SAME TIME, THE SNOW
SHOWERS ARE IN PATTERNS THAT THE MODELS ARE HAVING DIFFICULTY
DEPICTING. HOWEVER: THE MODELS HAVE A USEFUL CONSISTENCY IN
DEPICTING THE TAPERING OFF OF THE SHOWERS IN A NNW TO SSE
SEQUENCE AS THE LOW TRACKS FARTHER TO SE.

.LONG TERM...MODELS IN GOOD LARGE SCALE AGREEMENT UNTIL LATE
WEEK AND NEXT WEEKEND. UPPER PATTERN WILL AMPLIFY WITH A TROF
DEVELOPING OVER THE ERN PAC AS SHARP RIDGE BUILDS UPSTREAM OVER
THE CENTRAL PAC INTO THE BERING SEA BY THE WED-THU PERIOD. WILL
HAVE A FAIRLY LARGE SFC LOW THAT MOVES INTO THE CENTRAL GULF BY
TUE NIGHT BUT IT WILL HEAD SE WED-THU AS THE UPPER TROF AMPLIFIES
OVER THE AREA. BY NEXT WEEKEND MODELS DIFFER ON HOW STRONG THE
RIDGE WILL REMAIN TO THE W WITH THE ECMWF SHOWING IT BEING
FLATTENED BY A SYSTEM MOVING INTO THE SRN GULF WHILE THE GFS AND
UKMET MAINTAIN A SHARPER RIDGE OVER THE ERN BERING SEA AND FAR WRN
GULF. ENDED UP USING HPC FROM THU ONWARD AS A COMPROMISE. THE
PRESSURE GRIDS LOOKED GOOD FOR MON NIGHT INTO WED SO LEFT THOSE AS
IS.

 FOR MON NIGHT INTO EARLY TUE...SFC LOW WILL BE OVER FAR SE GULF
AT START OF PERIOD BUT WILL MOVE SE OF THE AREA LATER MON NIGHT.
WEAK ARCTIC HIGH OVER THE YUKON WILL HELP PUSH COLDER AIR SWD
ESPECIALLY OVER THE NRN AND CENTRAL AREAS MON NIGHT. WILL LIKELY
HAVE DECENT CLEARING ESPECIALLY OVER THE NRN AND CENTRAL
AREAS...WHICH WILL ALLOW TEMPS TO DROP FAIRLY EASILY IN WIND
SHELTERED AREAS...PROBABLY TO SINGLE DIGITS OVER THE NRN THIRD OF
THE AREA WITH SNOW COVER HELPING THIS. EVEN THE WINDIER AREAS
WILL BE FAIRLY COLD WITH TEMPS IN THE TEENS TO LOWER 20S OVER THE
NRN AND CENTRAL AREAS. THE WINDS SHOULD DECREASE MON NIGHT INTO
EARLY TUE AS PRESSURE GRADIENT WEAKENS. AIRMASS SHOULD BE COLD
ENOUGH OVER THE NRN CHANNEL WATERS FOR FREEZING SPRAY TO
CONTINUE...ESPECIALLY IN LYNN CANAL.

 FOR LATER TUE INTO WED NIGHT...LOW WILL MOVE INTO THE WRN GULF
TUE THEN REACH CENTRAL GULF TUE NIGHT. ASSOCIATED OCCLUDED FRONT
WILL AFFECT MAINLY THE ERN GULF AND SRN HALF OF THE PANHANDLE
WITH PRECIP WHILE NRN AREAS ONLY GET SOME CLOUDS. THIS SYSTEM
WILL HALT THE COLD AIR INTRUSION TUE NIGHT AND WED...SO SOME
SLIGHTLY WARMER TEMPS ARE LIKELY OVER THE NRN AND CENTRAL
AREA...BUT THEY WILL REMAIN WELL BELOW FREEZING. WINDS WILL PICK
UP AS WELL WITH GALES EXPECTED OVER MOST NRN AND CENTRAL CHANNELS
AND IN OUTFLOWS INTO THE NE GULF...AS WELL AS AHEAD OF THE
OCCLUDED FRONT OVER THE SE GULF. THE LOW WILL BEGIN TO HEAD SE
LATE WED INTO WED NIGHT...AND THIS WILL ALLOW COLDER AIR TO MOVE
BACK INTO THE NRN AND CENTRAL AREAS DURING THAT TIME AS ARCTIC
HIGH BUILDS OVER THE YUKON. ENDED UP LOWERING TEMPS SOME WED
NIGHT DUE TO THE COLDER AIR MOVING BACK IN.

 FOR LATE WEEK AND THE WEEKEND...LOOKS LIKE IT WILL BE FAIRLY
COLD OVER MUCH OF THE AREA WITH STRONG NLY LOW LEVEL FLOW
CONTINUING INTO AT LEAST FRI NIGHT. THE GFS AND UKMET KEEP THIS
FLOW GOING INTO THE WEEKEND WHILE THE ECMWF WEAKENS IT DUE TO SFC
HIGH TO THE N WEAKENING AND SHIFTING TO THE E. MAIN FORECAST
ADJUSTMENT MADE DURING THIS TIME WAS TO LOWER TEMPS SOME...BUT
NOT QUITE AS FAR AS THE MOS GUIDANCE SUGGESTED.

.AJK WATCHES/WARNINGS/ADVISORIES...
PUBLIC...STRONG WIND FROM LATE TONIGHT THROUGH MONDAY AFTERNOON FOR
     AKZ019.
         STRONG WIND FROM 6 PM AKST THIS EVENING THROUGH MONDAY AFTERNOON
     FOR AKZ018.
         STRONG WIND FROM 6 PM AKST THIS EVENING THROUGH MONDAY AFTERNOON
     FOR AKZ017.
MARINE...HEAVY FREEZING SPRAY WARNING FOR PKZ012.
         GALE WARNING FOR PKZ011>013.
         SMALL CRAFT ADVISORY FOR PKZ021-022-031-032-043-051>053.
         SMALL CRAFT ADVISORY DUE TO SEAS FOR PKZ041-042.

&&

JBT/RWT