Gale Warning 362, NWS Juneau, AK

SOUTHEAST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE JUNEAU AK
1222 PM AKST SUN NOV 16 2008

.SHORT TERM...SATELLITE THIS MORNING REVEALS A LARGE AMOUNT OF
HIGH LEVEL CIRRUS STREAMING NORTHWARD ACROSS THE SOUTHERN
PANHANDLE FROM A DEVELOPING SURFACE LOW IN THE NORTHEASTERN
PACIFIC. ELSEWHERE ACROSS THE CENTRAL AND NORTHERN PANHANDLE
SKIES REMAIN PARTLY CLOUDY TO SUNNY WITH AREAS OF FOG THIS
MORNING...MAINLY NEAR MARINE WATERS. THIS PATCHY FOG WILL
CONTINUE TO MIX OUT THIS MORNING GIVING WAY TO A SUNNY DAY AS MID
AND LOW LEVEL DRY OFFSHORE FLOW WILL CONTINUE TO STRENGTHEN INTO
THIS AFTERNOON AND EVENING. BOTH THE 06Z AND 12Z MODELS CONTINUE
TO STRUGGLE WITH THE DEVELOPING SURFACE WAVE AND ITS IMPACT ON
THE PANHANDLE. THE 12Z NAM IS NOW THE EASTERN OUTLIER, YESTERDAY
THE NAM WAS THE WESTERN OUTLIER, SO PREFERRED TO KEEP THE CURRENT
PACKAGE AS IS. AS THE 12Z GFS INITIALIZED THE BEST THIS MORNING
BLEND ITS SOLUTION INTO THE CURRENT PACKAGE, WHICH SLOWS DOWN THE
PROGRESSION OF THE SURFACE LOW...BUT KEPT THE STRENGTH OF THE
SURFACE LOW AROUND 1003 MB IN BETWEEN THE GFS/ECMWF SOLUTIONS.
WITH THIS SURFACE LOW MOVING ACROSS THE SOUTHERN PANHANDLE INTO
TOMORROW AND A DEVELOPING 1030 MB HIGH IN THE NORTHERN YUKON WILL
ALLOW FOR A STRONG NORTHERLY SURFACE PRESSURE GRADIENT TO FORM IN
THE LYNN CANAL AREA TONIGHT. AS THE SURFACE PRESSURE GRADIENT
ORIENTATION REMAINS FAVORABLE FOR SKAGWAY WILL SEE POSSIBLE WIND
ADVY GUSTS THERE STARTING LATE TONIGHT. ALSO WITH TEMPERATURES
ALONG THE KLONDIKE HIGHWAY DROPPING BELOW 10F TONIGHT WILL SEE
WIND CHILLS ALONG THE HIGHWAY TO -20F.

 FOR TONIGHT THE DEVELOPING SURFACE LOW IN THE NORTHEASTERN
PACIFIC WILL MOVE OVER THE CHARLOTTES AND INTO THE SOUTHERN
PANHANDLE. THIS WILL ALLOW PRECIP TO SPREAD NORTHWARD BUT WITH
THE EASTERLY WINDS AT LOW LEVELS EXPECT PRECIP AMOUNTS TO BE
LIGHT AND ONLY ACROSS THE SOUTHERN PANHANDLE. THE NORTHERLY
SURFACE PRESSURE GRADIENT WILL BECOME QUITE STRONG TONIGHT AND
WINDS WILL PICK UP IN SKAGWAY, LYNN CANAL, AND OUT OF INTERIOR
PASSES ALONG THE EASTERN INNER CHANNELS. EXPECT LOCALLY BREEZY
CONDITIONS IN THE JUNEAU, WITH THE STRONGEST WINDS OUT OF TAKU
INLET. COULD SEE PATCHY FOG IN WIND SHELTERED AREAS AGAIN TONIGHT
ACROSS THE CENTRAL AND SOUTHERN PANHANDLE BUT WITH THE HIGH LEVEL
CLOUDS ADVECTING IN FROM THE SOUTHWEST, DO NOT EXPECT FOG TO BE AS
WIDESPREAD AS THIS MORNING.

 FOR TOMORROW THE 1003 MB SURFACE LOW WILL MOVE NORTHEAST FROM
THE SOUTHERN PANHANDLE INTO BRITISH COLUMBIA. ATTM EXPECT PRECIP
TO MAKE IT AS FAR NORTH AS FREDERICK SOUND AND THE COAST
MOUNTAINS EAST OF STEPHENS PASSAGE, BUT THIS REMAINS DEPENDANT ON
THE SURFACE LOW TRACK. IF THE SURFACE LOW TRACKS FURTHER WEST
COULD SEE PRECIP IN THE JUNEAU AREA...BUT ATTM WITH THE STRONG
DRY NORTHERLY LOW AND MID LEVEL FLOW ANY PRECIP AMOUNTS WOULD BE
LIGHT. A WEAK DEFORMATION BAND DOES FORM ALONG STEPHEN PASSAGE
EARLY TOMORROW MORNING AND WITH THE COLD AIR IN PLACE COULD SEE
SNOW ACCUMULATIONS UP TO 2 INCHES WHERE THE DEFORMATION BAND SETS
UP...MAINLY NORTH AND WEST OF PETERSBURG. WILL SEE SNOW IN THE
HYDER AREA LATE TONIGHT AND TOMORROW MORNING BEFORE CHANGING TO
RAIN IN THE AFTERNOON WITH SNOW ACCUMULATIONS UP TO 4 INCHES.
WITH THE OFFSHORE FLOW CONTINUING TOMORROW NEAR YAKUTAT EXPECT
CONTINUED PARTLY CLOUDY TO MOSTLY CLEAR SKIES. THE WINDY
CONDITIONS WILL CONTINUE THROUGH TOMORROW AFTERNOON ACROSS THE
NORTHERN PANHANDLE AS THE SURFACE PRESSURE GRADIENT WILL REMAIN
STRONG THROUGHOUT THE DAY.

.LONG TERM...REASONABLY GOOD AGREEMENT AMONGST THE MODELS AT THE
BEGINNING OF THE LONG RANGE PERIOD BUT BY WEDNESDAY AFTERNOON
MODEL SPREAD BECOMES SIGNIFICANT. BY EARLY THURSDAY MORNING...CAN
ONLY SAY WITH CONFIDENCE THAT THERE WILL BE A SIGNIFICANT LOW
SOMEWHERE IN THE CENTRAL GULF WITH MODEL SOLUTIONS RANGING FROM
976 MB TO 993 MB. OPTED TO NOT MAKE ANY CHANGES BEYOND TUESDAY NIGHT
DUE TO MODEL AND RUN INCONSISTENCIES. USED UKMET FOR MONDAY NIGHT
AS AN EFFECTIVE MIDDLE GROUND BETWEEN GFS AND ECMWF. FOR TUESDAY
AND TUESDAY NIGHT...BLENDED UKMET AND EC TO BEST DEPICT A RIDGE
THAT BUILDS IN FROM THE SOUTH TO CONNECT WITH STRONG HIGH PRESSURE
MOVING EAST OVER THE INTERIOR AND YUKON.

&&

.AJK WATCHES/WARNINGS/ADVISORIES...
PUBLIC...WIND ADVISORY FROM 9 PM SUNDAY TO 6 PM MONDAY FOR AKZ018.
MARINE...GALE WARNING FOR PKZ012-013-052.
SMALL CRAFT ADVISORY FOR PKZ011-021-022-031>036-041>043-051.

&&

PSS/FRITSCH