Area Forecast Discussion
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FXAK67 PAJK 172336
AFDAJK

SOUTHEAST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE JUNEAU AK
336 PM AKDT WED SEP 17 2014

.SHORT TERM...A COMPLEX GALE FORCE LOW WILL MOVE NE INTO THE
CENTRAL GULF THU. COMPLEX FRONTAL SYSTEM WILL MOVE INTO THE ERN
GULF THU. USED BLEND OF THE 12Z GFS/ECMWF/GEM TO HANDLE THE
COMPLEX SYSTEM.

MAIN FORECAST CONCERNS WILL BE WINDS...PRECIP POTENTIAL...AND
WHETHER ANY FOG HANGS AROUND TONIGHT. RIGHT NOW...THE MOST WIND IS
OVER THE CENTRAL GULF NWD TO NEAR BUOY 46082. WINDS AROUND 25 KT
ARE OCCURRING THERE ATTM. THESE WINDS SHOULD INCREASE TO GALES
TONIGHT AS LOW AND STRONGER PART OF COMPLEX FRONT MOVES CLOSER TO
THE AREA. THE GALES SHOULD SPREAD TO MUCH OF THE REMAINDER OF THE
GULF BY LATE TONIGHT OR EARLY THU MORNING. THE STRONGER WINDS
SHOULD REACH THE OUTER COAST EARLY THU MORNING...AND THINK WIND
GUSTS TO 40-45 MPH WILL BE OCCURRING ALONG THE CENTRAL AND SRN
COAST AND FAR SRN INNER CHANNELS BY LATE THU MORNING. WILL BE
HEADLINING STRONG WINDS FOR ZONES 23...27...AND 28. MOST INNER
CHANNEL MARINE AREAS WILL REACH 25-30 KT THU AS FRONT MOVES TO THE
OUTER COAST BY LATE AFTERNOON...BUT THE FAR NRN INNER CHANNELS
WILL STAY SOMEWHAT LIGHTER DUE TO SLIGHT NLY PRESSURE GRADIENT
ORIENTATION.

AS FOR PRECIP...THERE MAY BE SPOTTY LIGHT SHOWERS OVER THE INNER
CHANNELS EARLY THIS EVENING AS SHALLOW CONVECTION WILL BE
OCCURRING (CAPE VALUES 50-80 J/KG). THIS SHOULD RAPIDLY DIMINISH
DUE TO LOSS OF DAYTIME HEATING. THEN...PRECIP FROM THE COMPLEX
FRONTAL SYSTEM WILL REACH THE SRN AND MUCH OF THE CENTRAL
PANHANDLE BY LATE TONIGHT...THEN OVERSPREAD REMAINDER OF PANHANDLE
THU MORNING. THE NE GULF COAST HAS SOME PRECIP ATTM ASSOCIATED
WITH WEAKER PART OF COMPLEX FRONT...BUT THIS SHOULD DIMINISH
TONIGHT AS LOWER LEVEL FLOW BACKS TO A MORE ELY DIRECTION DUE TO
APPROACH OF LOW AND STRONGER PART OF FRONT FROM THE S. THINK SOME
RAIN SHOULD MOVE BACK INTO THE PAYA AREA THU AFTERNOON AS FRONT
GETS CLOSE ENOUGH TO VEER SOME OF THE FLOW JUST OFF THE SFC TO A
MORE SELY DIRECTION.

AS FAR AS THE FOG GOES...COMBINATION OF THE SHALLOW CONVECTION
THIS EVENING AND THICKENING MID-LEVEL CLOUDS TONIGHT SHOULD
DISSIPATE ANY FOG BY EARLY THIS EVENING AND NOT ALLOW MORE TO
DEVELOP LATER TONIGHT. WILL NOT MENTION THE FOG FOR THIS PACKAGE
DUE TO THE RAPID DISSIPATION EXPECTED VERY EARLY IN THE PERIOD.

.LONG TERM...WET WEATHER CONTINUING THROUGH THE WEEKEND.
TEMPERATURES SHOULD REMAIN SLIGHTLY ABOVE NORMAL THROUGH THE LONG
TERM FORECAST PERIOD.

 THE START OF THE LONG TERM FORECAST PERIOD WILL FEATURE A 975-MB
LOW IN THE NORTH CENTRAL GULF, WITH ITS ASSOCIATED FRONT MAKING
LANDFALL ACROSS THE PANHANDLE LATE THURSDAY AFTERNOON. DO EXPECT
GUSTY WINDS ACROSS THE PANHANDLE. MOST AREAS SHOULD SEE
SOUTHEASTERLY WINDS AROUND 15 TO 25 MPH WITH HIGHER GUSTS IN
EXPOSED AREAS. GALE FORCE WINDS ARE EXPECTED ALONG THE OUTER
COAST, IN THE NORTH CENTRAL GULF, AND ALONG CLARENCE STRAIT. SMALL
CRAFT LEVEL WINDS WILL PREVAIL OVER THE INSIDE PASSAGE. THE GUSTY
CONDITIONS SHOULD PERSIST THROUGH THURSDAY NIGHT AS THE SECONDARY
WRAP ENHANCE WIND SPEEDS BEHIND THE WEATHER FRONT. ONCE THE
WEATHER FRONT PUSHES THROUGH, PRESSURE RISE WILL INDUCE ANOTHER
PUSH OF STRONG SOUTHERLY WINDS ACROSS THE INSIDE PASSAGE ON
FRIDAY. FOR NORTHERN LYNN CANAL, DO EXPECT GALE FORCE WINDS FOR
FRIDAY. WINDS IN SKAGWAY WILL BE GUSTING TO 40 MPH. BESIDES GUSTY
WINDS, DO EXPECT MODERATE RAIN TO FALL ACROSS THE PANHANDLE. SOME
AREAS WILL SEE LOCALLY HEAVY RAINFALL DUE TO ENHANCEMENTS FROM
TOPOGRAPHY.

 THERE WILL BE A BRIEF BREAK BEFORE A SHORT WAVE BRINGS IN
ANOTHER ROUND OF GUSTY WINDS AND RAIN TO THE PANHANDLE STARTING
EARLY SATURDAY. RIGHT NOW, MODELS ARE STRUGGLING IN PINPOINTING
THE STORM TRACK AND INTENSITY. BY SUNDAY, MODEL UNCERTAINTIES
CONTINUE TO INCREASE. THUS, KEEP LIKELY POPS FOR THE CWA.

 WITH THE STORM TRACK REMAINING MAINLY WEST OF THE PANHANDLE, DO
EXPECT WET AND SLIGHTLY ABOVE NORMAL TEMPERATURES. HIGHS WILL
TYPICALLY BE IN THE MID TO UPPER 50S, WHILE LOWS WILL BE IN THE
MID TO UPPER 40S.

 AREA STREAMS AND LAKES SHOULD SEE RISING WATER LEVELS. HOWEVER,
DUE TO FORECAST UNCERTAINTIES, IT IS TOUGH TO PINPOINT WHERE THE
HEAVY RAIN IS GOING TO HIT AT THIS POINT.

 FORECAST CONFIDENCE IS ABOUT AVERAGE THROUGH FRIDAY NIGHT, THEN
DROP TO BELOW AVERAGE BEYOND SATURDAY. UTILIZE A BLEND OF
ECMWF/GEM/GFS/OFFICIAL FOR DAY 2 TO DAY 4, THEN TRANSITION TO WPC
GUIDANCE BEYOND DAY 4.

&&

.AJK WATCHES/WARNINGS/ADVISORIES...
PUBLIC...STRONG WIND FROM THURSDAY MORNING THROUGH THURSDAY AFTERNOON FOR
     AKZ023-027.
         STRONG WIND FROM THURSDAY MORNING THROUGH THURSDAY EVENING FOR
     AKZ028.
MARINE...GALE WARNING FOR PKZ022-033-036-041>043-051-052.
         SMALL CRAFT ADVISORY FOR PKZ021-031-032-034-035-053.

&&

$$

RWT/RCL

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