Small Craft Advisory 40, NWS Juneau, AK

SOUTHEAST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE JUNEAU AK
541 AM AKST MON JAN 11 2016

.SHORT TERM...AN OCCLUDED FRONT OVER THE ERN GULF WILL DRIFT
NE TO THE OUTER COAST THIS AFTERNOON...THEN GO INLAND TONIGHT. A
LOW PRESSURE WAVE WILL MOVE NNW ALONG THE FRONT THROUGH THE ERN
GULF INTO THIS EVENING. ANOTHER LOW WILL MOVE N TOWARD THE SE GULF
LATE TONIGHT. USED BLEND OF THE 06Z NAM AND 00Z ECMWF...MAINLY TO
GET BEST ESTIMATE OF THE STRENGTH OF THE LOW PRESSURE WAVE MOVING
ALONG THE FRONT. THE NAM LOOKED A BIT WEAK WHILE THE ECMWF LOOKED
A BIT STRONG.

MAIN FORECAST CONCERNS WILL BE PRECIP POTENTIAL/TYPE/AMOUNTS AND
WINDS. MAIN PRECIP BAND WITH FRONT EXTENDS FROM THE SRN INNER
CHANNELS TO NEAR ICY BAY. EXPECT THE BAND TO SHIFT SLOWLY NE AS
FRONT MOVES THAT DIRECTION. THE LOW PRESSURE WAVE WILL INTENSIFY
THE PRECIP OUT AHEAD OF IT SOME. EVENTUALLY THE MAIN PRECIP BAND
WILL SHIFT FURTHER INLAND TODAY AND BEGIN TO DIMINISH ALONG THE
OUTER COAST EARLY TONIGHT AND MOST OF THE INNER CHANNELS LATER
TONIGHT AS THE FRONT MOVES THRU THEM. HOWEVER...MORE PRECIP WILL
SPREAD BACK INTO THE FAR SRN AREA LATE TONIGHT AS NEXT LOW MOVES
TOWARD THE SE GULF.

PRECIP SHOULD BE RAIN...EXCEPT IT LOOKS LIKE SNOW FOR THE FAR N
AND HYDER AREAS. THE FAR N SNOW WILL BE MAINLY AT HIGHER
ELEVATIONS ALONG THE HIGHWAYS. LOOKS LIKE A 3 TO 6 INCH SNOWFALL
FOR THAT FAR NRN AREA SO ISSUED A WINTER WEATHER ADVY FROM 18Z
TODAY TO 06Z TONIGHT FOR ZONES 18 AND 19. THE HYDER AREA MAY GET
AN INCH OR 2 OF SNOW TODAY AND AROUND 2 INCHES TONIGHT. RAINFALL
ELSEWHERE SHOULD BE 1/4 TO 3/4 OF AN INCH.

STRONGEST WINDS WILL BE ALONG OUTER COAST AND ERN GULF AHEAD OF
THE FRONT AND LOW PRESSURE WAVE. GENERALLY GALE FORCE WINDS ARE
EXPECTED OVER THE FAR ERN TO NRN GULF TODAY...WITH DIMINISHING
WINDS LATE THIS AFTERNOON AND EVENING AS LOW PRESSURE WAVE MOVES
ONSHORE NEAR ICY BAY. THE INNER CHANNELS WILL GENERALLY SEE UP TO
30 KT OF WIND WITH THE E-W CHANNELS HAVING MORE WIND THAN THE N-S
CHANNELS. THESE WINDS WILL DIMINISH LATE TONIGHT. LYNN CANAL WILL
START OUT WITH 10-15 KT NLY WINDS BUT ONCE FRONT MOVES
INLAND...THEY WILL SEE SLY SCA LEVEL WINDS AIDED BY 35-40 KT SWLY
FLOW AT 700 MB. WENT WITH STRONG WIND HEADLINES FOR ZONES 23 AND
27 TODAY WITH GUSTS TO 40-45 MPH EXPECTED.

.LONG TERM...PERIOD BEGINS AS THE TRANSITION TO A MORE ACTIVE WX
PATTERN CONTINUES. TUE WILL BEGIN WITH SHOWERS FROM MONDAY'S STORM
DISSIPATING WITH ANOTHER GALE FORCE LOW MOVING INTO THE GULF.
INSIDE CHANNELS WILL SEE THE BRIEF SOUTHERLY FLOW BECOME NORTHERLY
AND INCREASE AGAIN AS THE LOW APPROACHES FROM THE SOUTH WITH
ADVISORY LEVEL WINDS EXPECTED BY TUE NIGHT. THE SOUTHERN PANHANDLE
WILL ALSO NEED TO BE MONITORED FOR STRONG WIND HEADLINES AS THIS
STORM APPROACHES. MODEL SOLUTIONS CONTINUE TO DIVERGE WITH THE
TRACK OF THE SYSTEM WITH THE NAM AN EASTERN OUTLIER MOVING IT INTO
DIXON ENTRANCE. GFS/EC/GEM IN SIMILAR AGREEMENT ON A TRACK TOWARDS
THE N GULF COAST...BUT GFS IS FASTEST AND WEAKEST OF THE THREE.
MODELS SUGGEST ALL RAIN ACROSS THE PANHANDLE WITH THIS
SYSTEM...BUT FEEL PTYPE MAY BE A BIT MORE CHALLENGING...ESPECIALLY
OVER THE NRN INNER CHANNELS...AND DEPEND ON HOW LONG SOUTHERLY
FLOW PERSISTS BEFORE SHIFTING BACK TO THE N. SHOWERS WILL CONTINUE
THROUGH WED AS THE STORM SYSTEM MOVES THROUGH THE GULF. SHOWER
ACTIVITY WILL DIMINISH HEADING INTO THU AS A SHORTWAVE RIDGE
PASSES OVER THE REGION. MODELS IN FAIR AGREEMENT WITH UPPER RIDGE
BUILDING OVER THE E GULF/W N AMERICA FRI WHICH WILL RESULT COOLER
TEMPS HEADING INTO THE WEEKEND. RIDGE SHIFTS E AND UPPER FLOW
BECOMES SWLY OVER THE WEEKEND WITH PRECIP CHANCES INCREASING AS A
RESULT.

USED EC/GEM FOR UPDATES AND CONTINUED TRENDING TEMPS COOLER
HEADING INTO THE WEEKEND.

&&

.AJK WATCHES/WARNINGS/ADVISORIES...
PUBLIC...STRONG WIND UNTIL 3 PM AKST THIS AFTERNOON FOR AKZ027.
         STRONG WIND UNTIL 9 AM AKST THIS MORNING FOR AKZ023.
         WINTER WEATHER ADVISORY FROM 9 AM THIS MORNING TO 9 PM AKST THIS
     EVENING FOR AKZ018-019.
MARINE...GALE WARNING FOR PKZ041>043-051-052.
         SMALL CRAFT ADVISORY FOR PKZ012-013-021-022-031>036-053.

&&

RWT/BC

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