Flooding in Alaska, January 14, 2014

SOUTHEAST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE JUNEAU AK
346 PM AKST MON JAN 13 2014

.SHORT TERM...THE MAJORITY OF TIME IN THE AFTERNOON PACKAGE WAS
SPENT BOOSTING WINDS IN LINE WITH SOME REALLY IMPRESSIVE
850 WINDS FROM THE SOUTH...USING THE 70 PERCENT RULE...I SUPPOSE.
BUT THESE WILL BE DICEY... AS WINDS HAVE NOT SHOWN THEMSELVES
YET. HOWEVER, ECMWF, THE MODEL OF CHOICE HAS SEEMINGLY HELD BACK
THE FRONT A BIT FOR TONIGHT. STRONG WINDS AND WIDESPREAD GALES
WILL DEVELOP FIRST ALONG THE COAST AND IN THE SOUTH...AND THEN
SPREAD RAPIDLY UP TO JUNEAU LATE TONIGHT...EXPECT WIND GUSTS TO
45 MPH IN MANY LOCATIONS ACROSS THE REGION. CLARENCE STRAIT
SHOULD REACH STORM FORCE LATE TONIGHT AND REMAIN SO THROUGH
TUESDAY MORNING. WOULD NOT BE SURPRISED TO SEE LINCOLN ROCK GUST
TO HURRICANE FORCE. STAY OFF THE WATER IS THE MESSAGE WE ARE
TRYING TO COMMUNICATE. THESE STRONG WINDS...ALTHOUGH RELENTING
NEAR CROSS SOUND LATE TONIGHT, WILL CONTINUE IN THE OTHER
ZONES...THROUGH TOMORROW MORNING. BEHIND A STRONG COLD FRONT
PLOWING THROUGH THE WESTERN GULF...THE WINDS WILL SWITCH
SOUTHWESTERLY WITH SOME COLD AIR ADVECTION. THIS WILL TRANSLATE
850 MB WINDS MORE EASILY TO THE SURFACE, SO CONFIDENCE ACTUALLY
RISES IN WESTERLY WIND FORECASTS TOMORROW...WITH SMALL CRAFT TO
25 AT YAKUTAT BAY AND MORE IMPORTANTLY STORM FORCE ASSOCIATED
WITH A TIP JET INTO CROSS SOUND LATE TUESDAY AFTERNOON. NOT TO BE
OUTDONE...NORTHERN LYNN CANAL WILL ALSO RISE TO STORM FORCE
TOMORROW AFTERNOON AS A POST-FRONTAL RESPONSE TO THE LEE SIDE LOW
THAT STILL FAIRLY VIGOROUS IN THE CANADIAN YUKON. WHILE ECMWF
ADVERTISING GRADIENTS BETWEEN JUNEAU SKAGWAY OF -6.5 MB...ADD
50 PERCENT TO THIS TO ACCOUNT FOR A FRONTAL PASSAGE, AND THIS
SHOULD EASILY REACH STORM FORCE. WINDS WILL TURN WESTERLY LATE
TOMORROW AFTERNOON TUESDAY AFTERNOON IN THE COASTAL AND CENTRAL
ZONES TOMORROW AFTERNOON...WITH JUNEAU'S AUKE BAY GETTING SOME
SOUTHWESTERLIES...AND LIKELY THE AIRPORT, TOO. EVEN DOWNTOWN AND
DOUGLAS MAY BRIEFLY BECOME NORTHWEST FOR AWHILE.

 WITH THE TARDINESS OF THE FRONT...THE PRECIP SHIELD MAY BE
SLIGHTLY LATE, TOO...BUT HAVE NOT TAMPERED WITH QPF GRIDS AS THIS
WAS FRUITLESS EFFORT. WE HAVE BEEN COMMUNICATING HEAVY RAIN FOR
DAYS. AND THE SNOW WILL PILE UP HEAVY...INLAND AREAS OF LYNN
CANAL. BUT AS LYNN CANAL SOUTHERLY SURGE MORE IMPRESSIVE THAN
THOUGHT...THE TEMPERATURES AT SEA LEVEL HAVE WARMED UP IN THE
MIDDLE 30S TO 40 DEGREES. THIS FORCED US TO MIX IN RAIN EARLIER
THAN PREVIOUSLY THOUGHT AT SEA LEVEL. CONFIDENCE HAS FALLEN IN
WINTER STORM WARNING, HOWEVER, NOT ENOUGH TO PULL IT. WHILE NOT
NOTED IN THE ZONES, THERE MAY BE A BRIEF PERIOD OF FREEZING RAIN
NEAR THE CHANGEOVER ZONE, BUT FEEL LIKE THIS WILL BE EXTREMELY
SHORT-LIVED. CHANGED THE RANGE OF THE SNOWFALL AND EXPANDED IT TO
TAKE INTO ACCOUNT RAIN MIXING IN SOONER AT SEA LEVEL...NOW GOING
FOR 2 TO 14 INCHES OF SNOWFALL IN THE WARNED AREA...WITH GREATEST
AMOUNTS ALONG THE ROADS AWAY FROM THE WATER AND HIGHER IN
ELEVATION.

 HYDROLOGY WILL BE MONITORED TONIGHT WITH THE HEAVY RAIN MOVING
IN ACROSS THE PANHANDLE...BUT AT THIS TIME NOT EXPECTING ANY
ALARMS. IT WILL BE VERY WET AND A SLOG FOR THOSE LIVING ON
WET-SLUSHY STREETS. IN EXCESS OF AN INCH OF RAIN COULD FALL EVERY
SIX HOURS FOR LOCATIONS IN THE SOUTH AND CENTRAL COAST MOUNTAINS.
STAY HOME TONIGHT UNLESS YOU MUST PLAY IN YOUR RUBBER BOOTS.

.LONG TERM...LARGE SCALE PATTERN WILL CONTINUE TO FEATURE A
STRONG RIDGE OVER WESTERN NORTH AMERICA AND A FAIRLY DEEP TROF
OVER THE ALEUTIANS AND THE WESTERN PARTS OF AK. MODELS SUGGEST
THAT THE RIDGE MAY BE FLATTENED OVER THE AREA NEXT WEEKEND BUT IT
SHOULD REBUILD QUICKLY EARLY NEXT WEEK. THIS PATTERN WILL KEEP THE
AREA UNDER A FAIRLY MILD AIRMASS DURING MUCH OF THE UPCOMING WEEK
ALONG WITH PERIODS OF WET AND WINDY WEATHER. USED THE 12Z ECMWF
FOR TUE NIGHT INTO THU...THEN WENT WITH LATEST WPC FOR THU NIGHT
ON OUT FOR THE MOST PART. MAIN ADJUSTMENT TO THE LONGER RANGE WAS
TO WARM TEMPS SOME THRU EARLY NEXT WEEKEND.

 FOR TUE NIGHT...AREA WILL BE IN POST FRONTAL STRONG WLY FLOW.
PRECIP SHOULD HAVE ALREADY TRANSITIONED TO RAIN SHOWERS OVER THE
AREA BY TUE EVENING. MAIN CONCERN HERE IS POTENTIAL FOR STRONG TO
LOCALLY HIGH WINDS ESPECIALLY OVER THE FAR NRN INNER CHANNEL
AREA. DECIDED AGAINST ANY HEADLINES AT THIS POINT DUE TO ONGOING
WINTER STORM WARNING FOR THAT AREA. THE W-SW FLOW MAY ALSO DRIVE
SOME LARGE SWELLS INTO THE GUSTAVUS AND AUKE BAY AREAS.

 FOR WED AND WED NIGHT...A WEAK DISTURBANCE WILL RACE NE INTO THE
NRN GULF WED. THIS WILL BRING A MORE STEADY PRECIP TO THE NRN
GULF COAST AND POSSIBLY THE NRN PANHANDLE. A STRONGER SYSTEM
SHOULD MOVE INTO THE SW GULF WED NIGHT...AND THIS WILL SPREAD A
MORE WIDESPREAD AREA OF PRECIP IN...BUT ONCE AGAIN IT WILL BE
FOCUSED OVER THE NRN GULF COAST THE MOST. SOME PRECIP IS LIKELY
TO MOVE INTO THE NRN PANHANDLE AS WELL...AND GIVEN THE MILD TEMPS
IT SHOULD REMAIN RAIN. SHOULD SEE A BAND OF GALE FORCE WINDS OVER
THE GULF WED NIGHT WITH THIS SYSTEM AS WELL.

 FOR THU INTO FRI...WEAKENING OCCLUDED FRONT SHOULD REACH THE FAR
ERN GULF THU BUT MAY GET HELD UP ALONG THE OUTER COAST AS A
POTENTIALLY STRONG SYSTEM MOVES INTO THE GULF THU NIGHT AND FRI.
STILL...FRONT SHOULD KEEP FAIRLY GOOD THREAT FOR PRECIP OVER
MAINLY THE NRN AREA DURING THIS TIME...ALTHOUGH THERE MAY BE A
DRYING TREND FROM THE S LATER THU NIGHT AND FRI AS UPPER RIDGE
SHARPENS UP.

 FOR THE WEEKEND AND EARLY NEXT WEEK...UPPER TROF MAY FLATTEN THE
RIDGE SOME AND CAUSE A BIT OF COOLER AIR TO MOVE IN FROM THE
W...BUT OVERALL DO NOT SEE ANY SIGNIFICANT COLD AIRMASSES HEADING
INTO THE AREA. LATER SHIFTS MAY NEED TO BUMP TEMPS UP SOME FOR
THIS TIME FRAME...AND FURTHER LIMIT THE MENTION OF ANY SNOW.

.AJK WATCHES/WARNINGS/ADVISORIES...
PUBLIC...STRONG WIND FROM 9 PM AKST THIS EVENING THROUGH TUESDAY MORNING
     FOR AKZ023-026.
         STRONG WIND FROM 9 PM AKST THIS EVENING THROUGH TUESDAY
     AFTERNOON FOR AKZ027.
         STRONG WIND FROM MIDNIGHT AKST TONIGHT THROUGH TUESDAY MORNING
     FOR AKZ025.
         STRONG WIND FROM 9 PM THIS EVENING TO MIDNIGHT AKST TONIGHT FOR
     AKZ022.
         STRONG WIND TUESDAY AFTERNOON FOR AKZ022-023.
         STRONG WIND FROM 9 PM AKST THIS EVENING THROUGH TUESDAY MORNING
     FOR AKZ028.
         WINTER STORM WARNING UNTIL NOON AKST TUESDAY FOR AKZ018-019.
MARINE...STORM WARNING FOR PKZ012-022-036.
         GALE WARNING FOR PKZ011-013-021-031>035-041>043-051-052.
         SMALL CRAFT ADVISORY FOR PKZ053.

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JWA/RWT