Storm Warning 86, NWS Juneau, AK

809 
FZAK67 PAJK 121241
OFFAJK

OFFSHORE WATERS FORECAST
NATIONAL WEATHER SERVICE JUNEAU AK
400 AM AKST MON DEC 12 2011 

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.

PKZ398-130100-
400 AM AKST MON DEC 12 2011 
.SYNOPSIS FOR THE EASTERN GULF OF ALASKA...
A 977 MB NEAR PRINCE WILLIAM SOUND WILL MOVE INTO THE ALASKAN
INTERIOR AND WEAKEN TODAY. THE ASSOCIATED FRONT WILL CONTINUE TO
MOVE THROUGH THE PANHANDLE AND INTO CANADA THROUGH TONIGHT. 

$$

PKZ310-130100-
GULF OF ALASKA NORTH OF 55 DEGREES NORTH AND EAST OF 144 DEGREES
WEST-
400 AM AKST MON DEC 12 2011 

...GALE WARNING TODAY...

.TODAY...SW WIND 40 KT BECOMING W 30 KT IN THE AFTERNOON. SEAS
23 FT. 
.TONIGHT...W WIND 25 KT. SEAS 19 FT. SW SWELL. 
.TUE...W WIND 20 KT. SEAS 13 FT. W SWELL. 
.TUE NIGHT...SW WIND 20 KT. SEAS 10 FT. W SWELL. 
.WED...S WIND 25 KT. SEAS 9 FT. W SWELL. 
.THU...SE WIND 30 KT. SEAS 12 FT. 
.FRI...SE WIND 30 KT. SEAS 16 FT. 

$$

SOUTHEAST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE JUNEAU AK
553 AM AKST SUN DEC 11 2011

.SHORT TERM...WEATHER PATTERN FOR THE SHORT TERM IS SOMEWHAT
COMPLICATED AS ANOTHER FRONT BEGINS ITS PUSH THROUGH THE
PANHANDLE SUN NIGHT. TWO MAIN FORECAST PROBLEMS ARE ON THE
CHOPPING BLOCK. THE FIRST AND MOST COMPLEX IS HOW FAR NORTH AND
HOW FAST THE WARM ADVECTION AHEAD OF THE FRONT WILL PUSH THE
RAIN/SNOW LINE SUN NIGHT. THE SECOND IS THE WIND THAT WILL
ACCOMPANY THE FRONT ACROSS THE AREA.

 NAM IS ONCE AGAIN TRENDING COLD AS IT HAS FOR MOST OF THE SNOW
SEASON THIS YEAR KEEPING MOST INNER CHANNEL AREAS SOLIDLY IN SNOW
FOR MOST OF THE NIGHT. MEANWHILE THE GFS AND EC HAVE A WARMER
TREND THAT CHANGES MOST AREAS OVER TO RAIN AT SOME POINT DURING
THE NIGHT. THIS HAS A RATHER SEVERE IMPACT ON THE SNOW AMOUNT
FORECAST. IF YOU BELIEVE THE NAM MOST INNER CHANNEL AREAS WOULD
BE BURIED UNDER WARNING LEVEL SNOW FALLS. THE GFS SCENARIO JUST
BARELY GIVES ADVISORY LEVEL SNOWS FOR MOST OF THE INNER CHANNEL
AREAS AND YAKUTAT AND WARNING LEVEL FOR HAINES. GIVEN THAT MOST
AREAS IN THE PANHANDLE ARE JUST BELOW FREEZING THIS MORNING AND
SOME RATHER SUBSTANTIAL SOUTHERLY FLOW WILL BE PUSHED INTO THE
AREA SUN NIGHT, I AM MORE INCLINED TO BELIEVE THE WARMER SCENARIO
ESPECIALLY GIVEN WHAT SIMILAR STORMS THIS FALL HAVE DONE. HOWEVER
I DID BRING THE SNOW AMOUNTS UP A BIT FROM GFS AMOUNTS.

 WITH THAT IN MIND I HAVE TAKING THE WINTER STORM WATCH THAT WAS
UP FOR HAINES AND UPGRADED IT TO A WINTER STORM WARNING GIVEN
THAT BOTH SCENARIOS DIDN'T REALLY SHOW HAINES CHANGING OVER TO
RAIN. THE OTHER WATCHES I HAVE TURNED INTO ADVISORIES AS I THINK
THE WARM ADVECTION WILL PUT A DAMPER ON THE SNOW AMOUNTS BEFORE
THEY REACH WARNING CRITERIA. YAKUTAT I THINK WILL CHANGE OVER
SOMETIME SUNDAY EVENING AS E WINDS BECOME MORE SE. JUNEAU AND
PETERSBURG WILL START OUT AS SNOW THIS EVENING THEN START MIXING
WITH RAIN LATE AS SOUTHERLY FLOW INCREASES AS THE FRONT GETS
CLOSER. I HAVE ALSO PUT OUT ADVISORIES FOR GUSTAVUS, SKAGWAY, AND
HOONAH, AS THEY MAY GET ENOUGH SNOW BEFORE CHANGE OVER TO WARRANT
IT. HOONAH AND GUSTAVUS I THINK WILL START OUT AS SNOW EARLY THIS
EVENING BUT WILL EXPERIENCE CHANGE OVER DURING THE LATE EVENING.
SKAGWAY MAY NOT CHANGE OVER TO RAIN BUT IT WILL NOT SEE AS MUCH
QPF DUE TO THAT AREA USUALLY BEING ONE OF THE DRYER AREAS IN THE
PANHANDLE.

 THE SECOND MAJOR CONCERN IS THE WIND. THIS FRONT HAS A LOT OF
WIND ACCOMPANYING IT AS GALE AND EVEN STORM FORCE WINDS WILL BE A
CONCERN OUT IN THE GULF. FOR THE COASTAL AREAS, A 70 TO 80 KT LOW
LEVEL JET WILL BRING STRONG WIND HEADLINES TO MOST OF THE COASTAL
ZONES SUNDAY NIGHT. FARTHER INLAND THE LOW LEVEL JET WILL WEAKEN
BUT IT WILL STILL HAVE ENOUGH PUNCH TO BRING BREEZY TO WINDY
CONDITIONS. JUNEAU ITSELF MAY HAVE GUSTS UP TO 40 MPH SUNDAY
NIGHT AS THE JUNEAU TO YAKUTAT PRESSURE GRADIENT REACHES -14 MB.
MOST OF THE INNER CHANNEL MARINE ZONES WILL ALSO BE FEELING THE
BRUNT OF 30 KT SMALL CRAFT WINDS WITH SOME AREAS SEEING GALE
FORCE WINDS AS WELL SUNDAY NIGHT.

 MODEL AGREEMENT WAS NOT TOO BAD WITH THE EXCEPTION OF THE
TEMPERATURE AND SNOW FALL COMPONENTS. DECIDED TO STICK WITH GFS
MAINLY FOR THE WARMER SCENARIO AND THE REASONABLE INITIALIZATION
IT HAD THIS MORNING. FORECAST CONFIDENCE IS ABOUT AVERAGE DUE TO
THE UNCERTAINTY STILL PRESENT IN THE TEMPERATURE AND SNOWFALL
FORECASTS.

&&

.LONG TERM...OUR 975 MB LOW OVER PWS CONTINUES TO WEAKEN IN PLACE
MONDAY NIGHT AND DISSIPATES ON TUESDAY. THE ASSOCIATED FRONT OVER
SOUTHEAST ALASKA SLIDES OFF TO THE ESE WITH CAA SPREADING ACROSS
THE PANHANDLE. WESTERLY FLOW OVER THE GULF WEAKENS ON TUESDAY.
WEAK RIDGING SHIFTING FROM THE GULF OVER SOUTHEAST ALASKA
WEDNESDAY. NEXT FRONTAL BOUNDARY MOVES INTO THE EASTERN GULF BY
THURSDAY NIGHT.

EXPECT STRONG AND GUSTY WINDS SLY WINDS OVER THE PANHANDLE ON
MONDAY WITH GUSTS OVER 40 MPH MOST ZONES. THESE WINDS DIMINISH AND
SHIFT TO THE WEST BY AFTERNOON BEHING FRONT. A SW GALE OVER THE GULF
WILL BRING A 20 FOOT SW SWELL THAT WILL START TO DIMINISH MONDAY
NIGHT. RAIN OVER THE PANHANDLE WILL START TO CHANGE BACK TO SNOW
FROM THE NORTHWEST MONDAY NIGHT IN CAA FROM THE WEST WITH PRECIP
ENDING BY MORNING SO NOT BIG ACCUMULATIONS EXPECTED. SCATTERED
SNOW AND RAIN SHOWERS CONTINUE TO MOVE ONSHORE TUESDAY BUT AGAIN
NOT EXPECTED TO ADD UP TO MUCH.

CLOUDS BEGIN TO BREAK UP LATE TUESDAY LEADING TO A PARTLY CLOUDY
TUESDAY NIGHT AND WEDNESDAY. THIS WILL HELP TEMPS DROP WELL INTO
THE 20S AND INTO THE TEEN ACROSS THE NORTH. WINDS THROUGH THE
INNER CHANNELS GAIN NORTHERLY COMPONENT BUT OVERALL GRADIENTS ARE
NOT THAT STRONG. A WEAK UPPER DISTURBANCE MOVING ACROSS THE AREA
ON WEDNESDAY WILL BRING A RETURN OF HIGH CLOUDS AN ISOLATED SNOW
SHOWERS BUT IN GENERAL A NICE SE DAY.

RIDGE AXIS OVER SE ALASKA THURSDAY MORNING SHIFTS EAST BY
AFTERNOON ALLOWING NEXT FRONT TO SPREAD SE GALES AND PRECIP BACK
TO EASTERN GULF WHICH REACHES SOUTHEAST ALASKA FRIDAY.

GOOD MODEL AGREEMENT THROUGH THE SHORT TERM. MODELS HOLD ONTO THE
SAME GENERAL SYNOPTIC SOLUTIONS THROUGH THE LONG TERM BUT THERE
ARE IMPORTANT DIFFERENCES IN TIMING POSITION AND INTENSITY OF
INDIVIDUAL WAVES THAT I DO NOT TRY TO RESOLVE AT THIS TIME. USED
PRIMARILY A GFS BASED FORECAST FOR GRIDS BUT DID BLEND IN 06Z NAM
THROUGH 60 HOURS TO ADD DETAIL TO LEE TROUGH ACROSS SOUTHERN YUKON
ON MONDAY.

.AJK WATCHES/WARNINGS/ADVISORIES...
PUBLIC...WINTER WEATHER ADVISORY FROM 9 PM THIS EVENING TO 3 AM AKST
     MONDAY FOR AKZ026.
         STRONG WIND LATE TONIGHT FOR AKZ027.
         WINTER WEATHER ADVISORY FROM 6 PM THIS EVENING TO 3 AM AKST
     MONDAY FOR AKZ018-025.
         STRONG WIND FROM THIS EVENING THROUGH LATE TONIGHT FOR AKZ022-
     023.
         WINTER WEATHER ADVISORY FROM 3 PM THIS AFTERNOON TO MIDNIGHT
     AKST TONIGHT FOR AKZ020-021.
         WINTER STORM WARNING FROM 6 PM THIS EVENING TO 3 AM AKST MONDAY
     FOR AKZ019.
         WINTER WEATHER ADVISORY FROM 9 AM THIS MORNING TO 9 PM AKST THIS
     EVENING FOR AKZ017.
MARINE...STORM WARNING FOR PKZ051-052.
         GALE WARNING FOR PKZ012-022-033-035-036-041>043.
         SMALL CRAFT ADVISORY FOR PKZ011-013-021-031-032-034-053.

&&

EAL/MM