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000
FXAK67 PAJK 191342
AFDAJK

SOUTHEAST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE JUNEAU AK
542 AM AKDT SAT APR 19 2014

.SHORT TERM...RAIN HAS BEGUN TO SPREAD INTO THE SOUTHERN
PANHANDLE WITH HIGHER CLOUDS MOVING NORTH FROM THE BIG...BUT
RELATIVELY SLOW MOVING GALE FORCE LOW EDGING NORTHWARD INTO THE
EASTERN GULF. GALE FORCE WINDS ARE APPEARING IN DIXON ENTRANCE AT
BUOY 145...IN ADDITION TO CAPE DECISION CLIMBING TO GALE FORCE,
ALTHOUGH THIS PROBABLY AN OUTLIER FOR THE AREA AT THIS POINT.
BOUNDARY LAYER WINDS ARE RISING IN FRONT OF THIS STORM, AND EVEN
TAKING 30 PERCENT OF THE MAGNITUDE OF THESE OFF TO TRANSLATE AT
THE SURFACE, WE STILL WERE LEFT WITH GALES AT CLARENCE STRAIT AND
SOUTHERN CHATHAM STRAIT. THESE WINDS HAVE PRESENTED A FORECAST
CHALLENGE THE LAST FEW DAYS...ESPECIALLY FOR SATURDAY. THE
ORIENTATION IS NOT THE GREATEST FOR STRONG WINDS, BUT THEN AGAIN,
IT IS DIFFICULT TO IGNORE THE WINDS SCREAMING A SHORT WAYS ALOFT.
MANY OF OUR AIRPORT LOCATIONS MAY NOT VERIFY DURING THIS EVENT,
BUT SOME AREAS IN ZONES 27 AND 28 WILL HAVE SOME GOOD GUSTS FROM
THIS SETUP. METLAKATLA WILL GET MORE WIND THAN KETCHIKAN.
CONFIDENCE GROWS FOR STRONG WINDS THIS EVENING AS A FRONTAL
BOUNDARY CROSSES THE SOUTHERN PANHANDLE TO MOVE NORTH INTO THE
CENTRAL PANHANDLE. THE GRADIENT SETUP IS BETTER FOR SOUTHEAST
WINDS AT THE SURFACE, AND THUS AM MORE CONFIDENT ABOUT GALE FOR
CLARENCE...AND DID ADD SOUTHERN INNER CHANNELS AND BARANOF ISLAND
FOR STRONG WIND DURING THIS TIME PERIOD. KETCHIKAN WILL BLOW
STRONGEST THIS EVENING. SOUTHERLY WINDS WILL REACH ALL THE WAY
INTO LYNN CANAL BY LATE TONIGHT AS THE REMNANTS OF THE FRONT
SPREAD NORTHWARD, BUT THE EFFECTS/WINDS WILL BE WEAKER TO THE
NORTH.

 AS RAIN FALLS OVER THE SOUTHERN AREAS...THE NORTHERN ZONES WILL
SEE SOME HIGHER CLOUDS TODAY. MODELS ARE DETERMINING HIGHER
CLOUDS SPREADING NORTHWARD, BUT FEEL THAT IN THE JUNEAU/GUSTAVUS
AREA AND POSSIBLY POINTS FURTHER SOUTH, PEOPLE OUTSIDE WILL
EXPERIENCE SOME VARYING AMOUNTS OF SUNSHINE, SO WORDED THINGS
OPTIMISTICALLY AS PARTLY SUNNY. RAIN WILL HOLD OFF NORTH OF
FREDERICK SOUND UNTIL TONIGHT WITH THE RAIN SPREADING INTO
JUNEAU/GUSTAVUS AREA LATE TONIGHT. DID DECIDE TO WORD THE RAIN AS
LIGHT FROM JUNEAU NORTHWARD...AS THE LOW POSITIONING IN THE GULF
WILL BE HARD PRESSED TO DELIVER A BIG SOAKER OF ANY SORT. COULD
SEE IT BEING PERIODS OF SPRINKLES.

 ECMWF CONTINUES TO PERFORM WELL WITH THE SYSTEM. DID LEND A
LITTLE HELP FROM THE GEM FOR POPS/QPF. FORECAST CONFIDENCE ON THE
GOOD SIDE OF AVERAGE.

.LONG TERM...UPPER LOW OVER THE NE PAC AND SRN GULF WILL SHIFT
EWD AND WEAKEN THRU EARLY NEXT WEEK. WEAK UPPER HIGH WILL DEVELOP
OVER INTERIOR AK BY EARLY NEXT WEEK. WEAK UPPER TROF WILL DRIFT
NWD INTO THE SRN AREA BY MIDWEEK. AT THE SFC...A FAIRLY LARGE LOW
WILL BE HEADING SE OUT OF THE GULF SUN NIGHT. A SMALLER LOW LOOKS
LIKE IT WILL MOVE N INTO THE SE GULF SUN NIGHT THEN CURVE WWD INTO
THE NRN GULF AND WEAKEN MON. A WEAK SFC RIDGE WILL DEVELOP OVER
THE ERN GULF AND NRN SE AK BY LATE MON. USED THE 00Z ECMWF FROM
SUN THRU MON NIGHT...THEN TRANSITIONED TO LATEST WPC BY TUE NIGHT.

 FOR SUN-SUN NIGHT...TAIL END OF A WEAKENING OCCLUDED FRONT WILL
MOVE N THRU THE NRN AREA SUN MORNING. THIS FRONT WILL HAVE SOME
PRECIP  WITH IT ALTHOUGH THE AREAS CLOSER TO THE COAST MTNS WILL
SEE LESS PRECIP DUE TO ELY FLOW. THIS PRECIP SHOULD DIMINISH SUN
AFTERNOON.  MORE PRECIP SHOULD REACH THE SRN AREA LATER SUN
MORNING AND EARLY AFTERNOON AS A LOW MOVES N TOWARD THE SE GULF.
THIS SYSTEM MAY ALSO BRING ANOTHER ROUND OF STRONG WINDS TO THE
SRN PANHANDLE SUN AFTERNOON AND NIGHT AS WELL AS 30-35 KT WINDS
FOR THE SE GULF AND SRN INNER CHANNEL MARINE AREAS.
HOWEVER...GIVEN THE SMALL SIZE OF  THE SYSTEM...THESE WINDS WILL
NOT LAST MORE THAN A FEW HOURS IN MOST PLACES.

 FOR MON AND MON NIGHT...SMALL LOW CURVES INTO THE NRN GULF...AND
PRECIP SHOULD DIMINISH OVER MUCH OF THE MAIN PART OF THE
PANHANDLE MON. MAY BEGIN TO SEE SOME CLEARING OVER THE AREA MON
NIGHT AS WEAK RIDGE BUILDS OVER THE AREA.

 FOR TUE ON OUT...SE AK WILL GENERALLY BE IN BETWEEN SYSTEMS TO
THE SE AND W OF THE AREA. MAY SEE MINOR PRECIP THREATS FOR THE
SRN AREA DURING THIS TIME DUE TO PROXIMITY OF A WEAK SYSTEM TO
THEIR SE. THE NRN AREA WILL LIKELY SEE A DECENT AMOUNT OF
SUNSHINE TUE. HAVE ALLOWED MORE CLOUDS TO MOVE IN FROM THE S TUE
NIGHT AND WED AS WEAK UPPER TROF MOVES IN...BUT THIS MAY BE
OVERDONE AS THERE MAY BE LITTLE LOW LEVEL REFLECTION WITH IT. A
SYSTEM MAY TRY TO MOVE UP FROM THE S FOR LATE WEEK BUT MODELS ARE
IN POOR AGREEMENT BY THIS TIME. KEPT HIGHEST POPS OVER THE S FOR
LATE WEEK BUT LIMITED TO HIGH CHANCE LEVELS.

.AJK WATCHES/WARNINGS/ADVISORIES...
PUBLIC...STRONG WIND FROM 1 PM AKDT THIS AFTERNOON THROUGH LATE TONIGHT
     FOR AKZ027.
         STRONG WIND FROM THIS EVENING THROUGH LATE TONIGHT FOR AKZ023-
     028.
MARINE...GALE WARNING FOR PKZ033-036-041>043-051.
         SMALL CRAFT ADVISORY FOR PKZ012-013-021-022-032-034-035-052.

&&

$$

JWA/RWT





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