Gale Warning 355, NWS Juneau, AK

SOUTHEAST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE JUNEAU AK
402 PM AKST WED NOV 19 2014

.SHORT TERM...WEATHER TODAY IS RADICALLY DIFFERENT DEPENDING ON
WHICH PART OF THE PANHANDLE YOU ARE IN. ON A LINE FROM JUNEAU,
ANGOON AND JUST EAST OF SITKA SOUTHWARD, IT IS A RATHER WET DAY AS
WHAT IS LEFT OF YESTERDAY'S FRONT REMAINS MOSTLY STALLED OVER THE
SOUTHERN PANHANDLE. RAIN FALL AMOUNTS ACROSS THE SOUTH HAVE BEEN
IN THE QUARTER INCH RANGE EVERY 6 HOURS. WEST OF THAT LINE CLOUDS
BEGIN TO BREAK UP WITH PARTLY CLOUDY SKIES SHOWING UP OVER YAKUTAT
DUE TO THE RIDGE THAT HAS BUILT IN THE GULF. THE CLEARING ALLOWED
SOME FOG TO FORM IN THE NORTHERN INNER CHANNELS AND YAKUTAT THIS
MORNING AND THERE STILL IS SOME FOG LINGERING AROUND YAKUTAT,
SKAGWAY, AND GUSTAVUS RIGHT NOW.

NOT MUCH WILL CHANGE OVERNIGHT AS THE SIGNIFICANT FEATURES REMAIN
MOSTLY STATIONARY. SOUTHERN AND CENTRAL PANHANDLE WILL CONTINUE TO
SEE RAIN THROUGH THE NIGHT WITH RATES OF A QUARTER OF AN INCH
EVERY 6 HOURS STILL EXPECTED FROM THE STALLED FRONT. THE MAIN
CHANGES FROM TODAY IN THE SOUTH WILL BE DECREASING WINDS IN
CLARENCE STRAIT FROM 20 KT TO 10 KT OR LESS AS THE LOW LEVEL JET
POWERING IT GRADUALLY LOOSES ITS STRENGTH. FARTHER NORTH DRIER
CONDITIONS WITH BREAKS IN THE CLOUDS OVER THE NORTHERN PANHANDLE
(AND PARTLY CLOUDY SKIES OVER YAKUTAT) WILL CONTINUE OVERNIGHT.
YAKUTAT MAY PLUNGE INTO THE 20S FOR OVERNIGHT LOWS WITH THE LACK
OF CLOUD COVER AND LOW WINDS. FOR THE REST OF THE NORTHERN
PANHANDLE THE LINGERING CLOUDS WILL HELP KEEP THINGS A BIT WARMER
WITH MOST PLACE NOT GETTING BELOW FREEZING BUT A FEW MAY GET CLOSE.
ALSO WITH THE BREAKS IN THE CLOUDS, FOG MAY RETURN TONIGHT. AS
SUCH HAVE INCLUDED PATCHY FOR FOR A GOOD PORTION OF THE NORTHERN
PANHANDLE OVERNIGHT.

FOR THU, AGAIN NOT MUCH CHANGE BUT THE RIDGE IN THE GULF AND THE
FRONT OVER THE SOUTHERN PANHANDLE WILL START TO GET PUSHED EAST.
CONSEQUENTLY THE AREA OF DRIER WEATHER WILL SPREAD A BIT MORE INTO
THE CENTRAL PANHANDLE. HOWEVER RAIN WILL STILL FEATURE PROMINENTLY
IN THE FORECAST FOR THE SOUTHERN PANHANDLE THOUGH THU AFTERNOON.
WHAT IS DOING THE PUSHING IS THE NEXT FRONT THAT IS COMING ACROSS
THE GULF FROM THE SW. BY THU AFTERNOON IT WILL HAVE ONLY MADE IT
TO THE SW PORTION OF OFFSHORE ZONE 310 WHERE GALE FORCE SE WINDS
WILL BE STARTING TO GET KICKED UP IT. AS SUCH HAVE A GALE WARNING
STARTING UP FOR THE OFFSHORE ZONE THU AFTERNOON.

SHORT RANGE MODELS WERE IN GOOD AGREEMENT FOR THE NEXT 24 HOURS.
SOME SLIGHT DISAGREEMENT ON PRESSURE GRADIENT ACROSS THE NORTHERN
PANHANDLE BUT WERE ONLY VARYING BY ABOUT 1 MB OR SO. AFTER THAT
MAIN DISAGREEMENT WAS WITH THE FRONT ENTERING MARINE ZONE 310 THU
AFTERNOON. GFS IS A BIT SLOW COMPARED TO THE OTHER MODELS BUT IS
NOT OFF BY MUCH. MAINLY USED NAM WITH SOME ECMWF AND GEM DEPENDING
ON THE ELEMENT.

.LONG TERM...MAIN ISSUE IN THE EXTENDED RANGE REMAINS POTENTIAL
WAVE DEVELOPMENT ON FRIDAY AS A FRONTAL BOUNDARY MOVES ACROSS THE
PANHANDLE. AFTER THIS FRONT MOVES ONSHORE FLOW COMBINED WITH A FEW
WEAKER DISTURBANCES ROTATING IN THE PANHANDLE WILL RESULT IN
GENERALLY WET WEATHER THROUGH THE WEEKEND. MODEL SOLUTIONS BEGIN
TO DIVERGE BY NEXT WEEK ON THE PATTERN EVOLUTION BUT IT DOES
APPEAR SOME COOLER AIR WILL SLOWLY WORK ITS WAY INTO THE REGION.

MODELS ARE STILL STRUGGLING A BIT WITH THE POTENTIAL WAVE
DEVELOPING ALONG THE FRONT THURSDAY NIGHT AND INTO FRIDAY. WHILE
THIS WOULD HAVE SOME IMPACT ON WINDS ACROSS THE PANHANDLE, THERE
ARE SOME ASPECTS OF THE FORECAST THAT CONFIDENCE IS HIGH ON. THIS
FRONT WILL BRING A PERIOD OF GUSTY WINDS TO THE OUTER COAST AND
ESPECIALLY THE SOUTHERN PANHANDLE BEGINNING LATE THURSDAY NIGHT
AND DIMINISHING FRIDAY MORNING AS 925 MB WINDS OF 40-50 KT MOVE
OVER THE AREA. GALE FORCE WINDS CAN BE EXPECTED ACROSS THE
SOUTHERN INNER CHANNELS. THE FRONT WILL ACT TO STRENGTHEN THE
NORTHERLY PRESSURE GRADIENT OVER THE NORTHERN INNER CHANNELS WITH
WINDS STRENGTHENING TO SMALL CRAFT. IF A WAVE DOES DEVELOP AS THE
12Z ECMWF IS SUGGESTING THE STRONGER WINDS WOULD NEED TO BE
EXPANDED A BIT FARTHER TO THE NORTH. THERE WOULD ALSO BE STRONGER
WESTERLIES WINDS BEHIND THE LOW OUT OVER THE GULF AND INTO AREAS
SUCH AS CROSS SOUND. FOR THIS FORECAST PACKAGE, THE 12Z ECMWF
SOLUTION WAS NOT FAVORED BUT THE NEXT FEW SHIFTS WILL NEED TO
MONITOR THIS POTENTIAL. STEADY LIGHT TO MODERATE RAIN WILL
ACCOMPANY THIS FRONT WITH HEAVIEST AMOUNTS OVER THE SOUTHERN
PANHANDLE.

FOR THE REMAINDER OF THE LONG RANGE, CONTINUED ONSHORE FLOW AND
MULTIPLE WAVES ROTATING AROUND THE BASE OF THE PERSISTENT TROUGH
IN THE WESTERN GULF RESULTS IN WET WEATHER. TEMPERATURES ALOFT
LOOKS TO REMAIN WARM ENOUGH TO SUPPORT MAINLY LIQUID BEFORE SOME
COOLER AIR BEGINS TO TRICKLE INTO THE PANHANDLE EARLY NEXT WEEK.
HAVE MENTIONED SOME SNOW AT SEA LEVEL IN THE NORTHERN HALF OF THE
PANHANDLE EARLY NEXT WEEK BUT EVEN WITH SOME COOLING TEMPERATURES
REMAIN MARGINAL TO SUPPORT IT.

USED A BLEND OF THE 12Z NAM/GEM THROUGH DAY 4 THEN NEWEST WPC
GUIDANCE FOR THE REMAINDER OF THE EXTENDED. FORECASTER CONFIDENCE
REMAINS ABOUT AVERAGE WITH STILL SOME QUESTIONS ABOUT FRONTAL WAVE
DEVELOPMENT ON FRIDAY.

&&

.AJK WATCHES/WARNINGS/ADVISORIES...
PUBLIC...NONE.
MARINE...SMALL CRAFT ADVISORY FOR PKZ012-052.
         SMALL CRAFT ADVISORY DUE TO SEAS FOR PKZ022-041>043-051-053.

&&

EAL/TPS

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