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FXAK67 PAJK 190041
AFDAJK

SOUTHEAST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE JUNEAU AK
341 PM AKST THU DEC 18 2014

.SHORT TERM...WINDY GRAY DAY AS A STRONG FRONT BLASTS THE GULF
AND PANHANDLE. HIGH WIND WARNING REMAINS UP FOR ZONE 27 UNTIL 6 PM
WITH STRONG WIND HEADLINES FOR ZONES 23 AND 28. KETCHIKAN HAS
ALREADY RECEIVED GUSTS TO 41 KT TODAY WITH METLAKATLA GETTING 38
KT GUSTS AND KLAWOCK RECEIVING 33 KT GUSTS. FARTHER NORTH
NORTHEASTERLY WINDS AHEAD OF THE FRONT HAVE BEEN BLOWING GALE AT
ELDRED ROCK AND CROSS SOUND MOST OF THE DAY. WINDS ARE ALSO
GUSTING IN DOWNTOWN JUNEAU AS CROSS BARRIER FLOW OF AROUND 30 KT
WITH A MINOR CRUCIAL LEVEL HAS RESULTED IN GUSTS TO 45 MPH. AS
FOR PRECIP THE NORTHERN EDGE OF THE PRECIP SHIELD HAS REACHED
ANGOON (THEY STARTED SNOWING AROUND 11 AM) AND ELFIN COVE. OUTER
COAST LOCATIONS ARE WARM ENOUGH THAT THE PRECIP IS RAIN BUT INNER
CHANNEL AREAS FROM ANGOON NORTHWARD ARE COLD ENOUGH FOR THE PRECIP
TO START OUT AS SNOW. LITTLE ACCUMULATION HAS OCCURRED SO FAR AS
THE PRECIP IS JUST STARTING OUT AND ANGOON WAS ABOVE FREEZING
ANYWAY.

THE FRONT WILL CONTINUE ITS JOURNEY NORTH THROUGH TONIGHT.
ACCOMPANYING IT IS A TRIPLE POINT LOW THAT HAS FORMED ALONG THE
FRONT JUST WEST OF HAIDA GWAII AS SEEN AS A KINK IN THE CLOUD
SHIELD IN SATELLITE IMAGES. ITS THIS FEATURE THAT CONCENTRATES THE
WINDS IN ZONE 27 TODAY, BUT BY TONIGHT IT WILL HAVE WEAKENED AND
MOVED INTO THE CENTRAL GULF. SHORT RANGE MODELS, AFTER A FEW FITS
OVER THE LAST 24 HOURS ARE REPRESENTING THIS FEATURE RATHER WELL.
12Z ECMWF AND 18Z NAM SEEM TO HAVE A DECENT HANDLE ON IT WITH GFS
A CLOSE SECOND. HOWEVER NAM SEEMS TO BE JUST A BIT SLOWER WITH
LIFTING IT INTO THE CENTRAL GULF TONIGHT COMPARED TO EVERYTHING
ELSE. AGREEMENT WITH THE NEXT WAVE COMING UP FROM THE SOUTH ON FRI
IS BETTER AND MOST MODELS HAD IT WELL REPRESENTED. DECIDED ON
TRENDING TOWARD THE ECMWF FOR THE PRESSURE FIELD AND GFS FOR WIND
GUIDANCE.

WINDS ACROSS THE SOUTHERN PANHANDLE AND SE GULF SHOULD START TO
DIMINISH THIS EVENING. SAME FOR THE WINDS IN THE NORTHERN
PANHANDLE AS PRESSURE GRADIENTS SLACKEN OFF. AS THE FRONT MOVES
NORTH THE WINDS AND PRECIP WITH IT START TO DIMINISH AS THE FRONT
SHEARS APART UNDER DIVERGENT FLOW ALOFT. AS A RESULT WINDS AND
PRECIP AMOUNTS ACROSS THE NORTH WILL BE A FRACTION OF WHAT THE
SOUTHERN PANHANDLE GOT (.10 FOR THE NORTH VS AROUND .50 FOR THE
SOUTH). SPEAKING OF THE NORTH LOW LEVEL NORTHERLY WINDS HAVE BEEN
KEEPING TEMPERATURES NEAR FREEZING AT HAINES, SKAGWAY, AND THE
MENDENHALL VALLEY. THESE AREAS COULD SEE SNOW TONIGHT BEFORE WARM
AIR ADVECTION TURNS IT BACK TO RAIN TOMORROW. ANY ACCUMULATIONS
WILL BE AROUND 1 INCH OR LESS SINCE QPF AMOUNTS TAPER OFF AS THE
FRONT MOVES NORTH AND SURFACE TEMPS WILL BE RIGHT AROUND OR ABOVE
FREEZING.

INTO TOMORROW THE MAIN FRONT WILL BE WEAKENING OVER THE NORTHERN
PANHANDLE FRI MORNING. MEANWHILE A TRAILING TROUGH WILL BE SLIDING
INTO THE SOUTHERN PANHANDLE FROM THE SOUTH BRINGING ANOTHER SHOT
OF RAIN AND WIND. WITH 850 MB WINDS OF AROUND 50 KT, NOT EXPECTING
ANY HIGH WIND WARNINGS NEEDED FOR TOMORROW BUT STRONG WIND
HEADLINES FOR GUSTS TO 50 MPH WILL BE HOISTED FOR FRI FOR THE
SOUTHERN PANHANDLE WITH GALES FOR THE EASTERN GULF AND CLARENCE
STRAIT. RAIN WILL NOT BE THAT SUBSTANTIAL EITHER WITH ONLY ANOTHER
HALF AN INCH EXPECTED IN THE SOUTHERN PANHANDLE ON FRI.

.LONG TERM.../ FRIDAY NIGHT THROUGH THURSDAY / THE TROUGH ASSOCIATED
WITH THE TRAILING SHORT WAVE IS ROTATING NORTH PAST THE NORTHERN
HALF OF THE COASTAL PANHANDLE FRIDAY EVENING. THE TRIPLE POINT
FEATURE OF THE NEXT WAVE WILL BE PUSHING EAST INTO THE
SOUTHEASTERN GULF FRIDAY NIGHT. THIS FEATURE SHOULD BE IMPACTING
THE SOUTHERN PANHANDLE WITH A BURST OF GUSTY WINDS ON SATURDAY
MORNING. AFTER THAT A BROAD COMPLEX AREA OF LOW PRESSURE WILL
PERSIST OVER THE NORTHERN GULF THROUGH THE WEEKEND. SMALL SHORT
WAVES WILL CONTINUE TO SPREAD SOME SHOWERS ONSHORE THROUGH THE
WEEKEND. NOT LOOKING FOR ANY EXCESSIVE PERIODS OF RAIN ESPECIALLY
THROUGH THE WEEKEND.

TEMPERATURES OVER THE NORTHERN PANHANDLE WILL BE MAKING THE FORECASTING
INTERESTING. NOT ENOUGH COLD AIR IN PLACE TO SAY SNOW THE WHOLE
TIME...AND TO COOL TO SAY IT WILL BE RAIN. THUS ENDED UP WITH MIXED
PRECIPITATION, AMOUNTS GENERALLY AN INCH OR LESS.

THERE SHOULD NOT BE MUCH MOVEMENT ON THE LOW OVER THE NORTHERN
GULF BECAUSE THE STRONG JET STREAM WITH A CORE 160-180+ KT
PERSISTING AND AIMING THE MAIN WEATHER ENERGY WELL TO OUR SOUTH TO
VANCOUVER ISLAND. THE LIGHTER WINDS ON THE NORTH SIDE NOT ENOUGH TO
MOVE THE LOW STATIONED THERE.

AROUND SUNDAY A WAVE DIGGING SOUTHWARD FROM THE WESTERN BERING SEA
WILL DEEPEN THE LONG WAVE TROUGH ALOFT AND WILL SHIFT THE
ORIENTATION OF THE JET STREAM TO A MORE NORTHEAST PATTERN WHICH
WILL LIKELY LEAD TO A SLIGHTLY STRONGER FEATURE FOR THE SOUTHERN
HALF OF THE PANHANDLE.

FOR THE TAIL END OF THE FORECAST PACKAGE THE SURFACE LOW
DISSIPATES THROUGH THE EARLY HALF OF NEXT WEEK WHILE THE UPPER
LEVEL THROUGH BEING REPLACED BY BUILDING RIDGE ALOFT AHEAD OF A
STRONG UPPER 940 LOW IN THE BERING SEAS. THE FRONT ASSOCIATED WITH
THAT LOW WILL ARCING ACROSS THE GULF WEDNESDAY NIGHT AND HEADED TO
THE PANHANDLE FOR THURSDAY.

&&

.AJK WATCHES/WARNINGS/ADVISORIES...
PUBLIC...HIGH WIND WARNING UNTIL 6 PM AKST THIS EVENING FOR AKZ027.
         STRONG WIND FROM FRIDAY MORNING THROUGH FRIDAY AFTERNOON FOR
     AKZ027.
         STRONG WIND UNTIL 9 PM AKST THIS EVENING FOR AKZ025.
         STRONG WIND UNTIL 6 PM AKST THIS EVENING FOR AKZ023-028.
         STRONG WIND FROM FRIDAY MORNING THROUGH FRIDAY AFTERNOON FOR
     AKZ023-028.
MARINE...STORM WARNING FOR PKZ041>043.
         GALE WARNING FOR PKZ012-022-033-036-051-052.
         SMALL CRAFT ADVISORY FOR PKZ011-013-021-031-032-034-035.
         SMALL CRAFT ADVISORY DUE TO SEAS FOR PKZ053.

&&

$$

EAL/BEZENEK

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