Area Forecast Discussion
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000
FXAK67 PAJK 201358
AFDAJK

SOUTHEAST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE JUNEAU AK
558 AM AKDT SAT SEP 20 2014

.SHORT TERM...YET ANOTHER LOW IS SPEEDING NORTHWARD ACROSS THE
EASTERN GULF AND WILL MAKE LANDFALL AROUND CHICHAGOF ISLAND LATE
THIS MORNING. AN ASSOCIATED WEATHER FRONT IS RESPONSIBLE FOR STRONG
WINDS AND GALES ACROSS THE SOUTH THIS MORNING. DEFINITE
VERIFICATION WITH GUSTS TO 45 MPH ALONG THE SOUTHERN INNER CHANNELS
AND TO 50 MPH ON PRINCE OF WALES ISLAND. LINCOLN ROCK IS GUSTING TO
HURRICANE FORCE AT THIS HOUR. THESE STRONG SOUTHERLY WINDS WILL
SPREAD NORTHWARD THROUGH THE DAY...FLIPPING WIND NORTHERLY WIND
DIRECTIONS ACROSS THE NORTHERN PANHANDLE...BUT WILL WEAKEN AS THE
LOW MAKES LANDFALL. THINK THE SETUP AROUND JUNEAU WILL ONCE AGAIN
BE RIPE FOR SOME STRONG GUSTINESS AROUND MID-DAY WITH GALES BACK
SIDE OF DOUGLAS...PROBABLY EARLY AFTERNOON. BUT IF THE ECMWF IS
CORRECT WITH THE POSITIONING OF THE LOW...AS IT IS A BIT FASTER,
THE STRONG WIND GUSTS IN JUNEAU COULD OCCUR BEFORE NOON. STILL KEPT
THE STRONG WINDS FOR SKAGWAY FOR LATE AFTERNOON AS IT MAKES SENSE
WITH THE RIDGE POPPING UP BEHIND THE DIMINISHED LOW`S EXIT INTO
CANADA.

THE RIDGE BEGINS TO BREAK DOWN FIRST OVER THE SOUTHERN PANHANDLE
AND THEN OVER THE NORTH LATE TONIGHT AS THE NEXT LOW ONCE AGAIN
APPROACHES THE EASTERN GULF BY LATE SATURDAY NIGHT...AND FLIPS THE
NORTHERN PANHANDLE BACK TO NORTH.

THE BAND OF RAIN STALLED OVER THE SOUTHERN PANHANDLE WILL MOVE VERY
LITTLE TODAY AS THE UPPER LEVEL WINDS WILL REMAIN
SOUTHERLY/SOUTHWESTERLY. HOWEVER THE NEXT SYSTEM WILL BE DEEP
ENOUGH TO INDUCE SOME NEGATIVE TILTING THUS ALLOWING FOR THE RAIN
TO PUSH NORTH AGAIN WITH A FRONT. THE BAND OF HEAVY RAIN WILL
PERSIST GENERALLY SOUTH/EAST OF PETERSBURG THROUGH THIS EVENING
BEFORE ADVANCING TO JUNEAU/TENAKEE/SITKA LATE TONIGHT.

SOME ISOLATED THUNDERSTORMS PERSISTED OVER THE NORTHERN OUTSIDE
WATERS AND YAKUTAT OVERNIGHT, BUT THE INSTABILITY SHOULD DECREASE
ENOUGH WITH THE ADVANCING LOW THIS MORNING TO HELP PUSH THIS THREAT
OUT OF OUR CWA TO THE WEST LATER THIS MORNING.

SOME CREEKS ARE RISING THIS MORNING...OVER THE SOUTHERN
AREAS...NOTABLY THE STANEY NEAR KLAWOCK. THESE WILL BE MONITORED
TODAY. BUT STILL SEVERAL FEET BELOW ACTION.

NAM/ECMWF USED FOR UPDATES...MAINLY TODAY TO HELP DRIVE THE
SYSTEM`S WINDS FARTHER NORTHWARD INTO THE PANHANDLE THAN PREVIOUSLY
FORECAST. FORECAST CONFIDENCE GOOD TO AVERAGE.



.LONG TERM...MOST OF THE 00Z RUNS HAD A SIMILAR PATTERN ON SUNDAY
AS DEVELOPING LOW MOVES FROM THE EASTERN PACIFIC NORTH OVER THE
EASTERN GULF AND BACK TOWARDS THE NORTHEAST GULF SUNDAY NIGHT. THE
MODELS HAD VARY INTENSITIES AND POST IONS BU MOST AGREED THE LOW
SHOULD DEVELOP TO AT LEAST THE MID 970S. USED A BLEND OF THE
MODELS THE QUICKEN THE PACE SLIGHTLY FOR SUNDAY NIGHT AND THEN
ALSO STRENGTHENED THE WINDS ALONG THE FRONT TO MAX GALES AND SOME
MIN STORM FORCE ACROSS THE NORTHEAST GULF COASTAL WATERS. PULLING
NORTHWARD FROM ITS SOURCE REGION IT SHOULD EXPECT TO SEE SOME GOOD
RAINFALL AS THE ESPECIALLY THE NORTHEAST GULF COAST. RIVER LEVELS
SHOULD BE UP DO NOT THINK FLOODING WILL BE AN ISSUE.

AS THE LOW MOVES NORTHWARD EXPECT A BAND OF STORM FORCE ALONG THE
FRONT THAT WILL BE WEAKENING BY MONDAY MORNING AS THE LOW REACHES
THE NORTHERN GULF. THE STRONG WIND ALONG WITH A FAIRLY STRAIGHT
PATH OF THE LOW SHOULD DRIVE SEAS TO INCREASE SIGNIFICANTLY FOR
NOW MOST ARE 20 TO 25 FEET BUT COULD POSSIBLY SEE HIGHER NUMBERS.

WILL LIKELY BE NEEDING ANOTHER ROUND STRONG WIND HEADLINES FOR
COASTAL AREAS SUNDAY NIGHT... OR IF THE FRONT REMAINS AS STRONG AS
IT LOOKS IT MIGHT MIGHT EVEN BE STEP UP TO TO BIGGER ISSUES.

LATER PORTIONS OF THE FORECAST WHEN THE UPPER LEVEL TROUGH HAS
SHIFTED AND THE JET STREAM HAS THE FLOW MOVING SOUTH OF THE GULF
TOWARD THE VANCOUVER ISLAND ARE A PULLS SOUTHEAST ALASKA OUT OF
THE ACTIVE WEATHER PATTERN. THIS HAS SHIFTED MUCH FROM EARLIER
FORECASTS SO ONLY MINOR CHANGES TO THAT FORECAST.

FORECAST CONFIDENCE FOR SUNDAY RISING BUT HOVERING AT AVERAGE NOW
AND AVERAGE FOR THE LATER TIME FRAMES.

&&

.AJK WATCHES/WARNINGS/ADVISORIES...
PUBLIC...STRONG WIND UNTIL 1 PM AKDT THIS AFTERNOON FOR AKZ026-028.
         STRONG WIND UNTIL 10 AM AKDT THIS MORNING FOR AKZ027.
         STRONG WIND FROM 1 PM TO 4 PM AKDT THIS AFTERNOON FOR AKZ025.
         STRONG WIND FROM 4 PM AKDT THIS AFTERNOON THROUGH THIS EVENING
     FOR AKZ018.
MARINE...GALE WARNING FOR PKZ031-033>036-041-042.
         SMALL CRAFT ADVISORY FOR PKZ012-013-021-022-032-043.
         SMALL CRAFT ADVISORY DUE TO SEAS FOR PKZ051>053.

&&

$$

JWA/BEZENEK

VISIT US AT HTTP://WWW.WEATHER.GOV/JUNEAU








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