Gale Warning 260, NWS Juneau, AK

SOUTHEAST ALASKA FORECAST DISCUSSION
1100 AM ADT THU OCT 11 2007

.SYNOPSIS...
.SHORT RANGE...THE CURRENT SATELLITE IMAGERY SHOWS THE PANHANDLE
UNDER CLOUDY SKIES WITH NUMEROUS SHOWERS MOVING ONSHORE AS
INDICATED BY BIORKA RADAR. THESE SHOWERS WILL PERSIST THROUGH
MOST OF THE DAY AND INTO TONIGHT AS A MOIST ONSHORE FLOW WILL
REMAIN OVER THE FORECAST AREA. THE SOUTHERN AREAS MAY SEE SOME
DRIER CONDITIONS LATER ON TONIGHT AS ONCE A UPPER TROF LIFTS OVER
THE AREA THIS EVENING THE SHOWERS WILL BECOME MORE SCATTERED WITH
A WEAK UPPER RIDGE OVER THEM. THE ONLY SIGNIFICANT WINDS ACROSS
THE PANHANDLE THIS MORNING ARE OVER THE FAR NORTHERN INNER
CHANNELS NEAR PAGY REACHING ADV LEVEL. THESE GUSTY WINDS WILL
SLOWLY DIMINISH THROUGH THIS AFTERNOON AND BY TONIGHT THE WINDS
WILL BE LESS THAN 15 MPH.

THE BIGGEST SHORT TERM PROBLEM THIS MORNING IS THE ONSET OF A
VERY STRONG LOW MOVING INTO THE NORTHERN GULF THROUGH FRI. A WAVE
SOUTH OF THE AK PENINSULA ATTM WILL SPIN UP TONIGHT AND DEEPEN TO
AROUND 975MB AND ROTATE INTO THE NW GULF BY FRI AFTERNOON. THE
STRONG ASSOCIATED WEATHER FRONT WILL PUSH EAST INTO THE FAR
EASTERN GULF BY THE AFTERNOON. THIS FRONT WILL INCREASE WINDS
OVER THE SOUTHERN HALF OF THE COASTAL WATERS TO MIN GALES BY THE
LATE AFTERNOON. OVER THE NORTHERN HALF A BARRIER JET DEVELOPING
BY THE AFTERNOON OVER THE FAR NORTHERN GULF AND NEAR THE
FAIRWEATHER GROUNDS TO INCREASE THE WINDS TO STORM FORCE 50KT.
THE INSIDE WATERS WILL SEE THE WINDS IN EAST/WEST CHANNELS
INCREASE TO MIN GALES OVER THE NORTHERN ARES AND TO MAX SMALL
CRAFT OVER THE SOUTHERN AREAS. THE NORTH/SOUTH CHANNELS WILL SEE
THE WINDS INCREASE TO 25KT BY THE AFTERNOON THE ONLY EXCEPTION
WILL BE IN NORTHERN LYNN CANAL AND THE GRADIENT IS NOT FAVORABLE
FOR STROM WINDS DURING THIS TIME FRAME.

AS FOR THE LAND AREAS...THE WIND WILL INCREASE NEAR PAYA IN THE
MORNING AND BY THE NOON WINDS SHOULD BE NEAR WIND ADV LEVELS.
THESE WINDS WILL SPREAD SOUTHWARD ALONG THE COASTAL AREAS AND BY
MID AFTERNOON WIND GUSTS WILL BE ADV LEVEL OVER ZONES 22 AND 23.
THE REST OF THE PANHANDLE WILL SEE THE WINDS INCREASE THROUGH THE
DAY TO BECOME BREEZY BUT IT WILL NOT HIT ITS FULL STRENGTH UNTIL
THE EVENING...SEE LONG TERM FOR MORE DETAILS.

THE RAIN WITH THIS SYSTEM WILL BEGIN OVER PAYA TONIGHT AND SPREAD
SE OVER THE REST OF THE PANHANDLE THROUGH THE DAY. RAIN RATES
WILL BE ON THE HIGH SIDE AS THIS SYSTEM PICKUP TROPICAL MOISTURE
AS IT CAME ACROSS THE PACIFIC. ALSO THERE IS VERY GOOD JET
DYNAMICS ASSOCIATED WITH THE FRONT SO RAIN WILL BE HEAVY AT TIMES
AS THE FRONT COMES ASHORE IN THE AFTERNOON.

.LONG RANGE...CURRENTLY EXPECT THE FRONT TO EXTEND ALL THE WAY
DOWN TO THE DIXON ENTRANCE FRIDAY NIGHT WITH A WELL DEFINED WAVE
COMING ASHORE ALONG THE CENTRAL COAST EARLY SATURDAY MORNING.
THIS WAVE WILL BE SUPPORTED BY A STRONG SOUTHWESTERLY JET STREAK
LYING OVER CAPE DECISION EARLY SATURDAY MORNING THAT WILL SLIDE
SOUTH THROUGHOUT THE DAY. AT THIS POINT...NO FOLLOW ON
CYCLOGENESIS IS EXPECTED OUT OF THIS WAVE INSOFAR AS IT WILL
IMPACT THE WEATHER OVER THE PANHANDLE.

A BARRIER JET FROM CAPE SPENCER NORTH WILL GENERATE GALE FORCE
WINDS IN COASTAL WATERS AT THE BEGINNING OF THE LONG RANGE PERIOD
BUT WILL EASE CONSIDERABLY LATE FRIDAY NIGHT AS THE COASTAL
PRESSURE GRADIENT RELAXES FROM NORTH TO SOUTH. STRONG SOUTH WINDS
WILL LAST THROUGH THE NIGHT IN THE DIXON ENTRANCE...DECREASING TO
SMALL CRAFT DURING THE DAY SATURDAY. BASED ON THE ORIENTATION OF
THE PRESSURE GRADIENT...THE EAST-WEST ORIENTED INNER CHANNELS
SHOULD SEE THE STRONGEST WINDS AND SO THINK THAT GALES ARE LIKELY
IN ICY STRAIT...CROSS SOUND...FREDERICK SOUND...AND SUMNER
STRAIT. AS THE PRESSURE GRADIENT ORIENTATION BECOMES MORE
NORTHWEST TO SOUTHEAST BY SATURDAY MORNING...CLARENCE STRAIT WILL
LIKELY SEE SOUTHEAST GALES AS WELL. LYNN CANAL AND NORTHERN
CHATHAM ARE LOOKING LIKE THEY WILL PEAK AT SMALL CRAFT DURING THE
NIGHT. BIGGEST QUESTION IS HOW STRONG THE WINDS WILL GET IN
SOUTHERN CHATHAM STRAIT. SMALL CRAFT FOR SURE BUT MINIMAL GALE
SOUTH OF FREDERICK SOUND POSSIBLE.

WIND ADVISORIES LIKELY FOR MOST ZONES EARLY FRIDAY NIGHT.
ANTICIPATE THAT BY SATURDAY MORNING ADVISORIES WILL STILL BE IN
PLACE FOR ZONES 27...28...AND 29.

VERY LITTLE CHANGE TO THE RAINFALL FORECAST WITH MOST LOCATIONS
RECEIVING 1 INCH OR MORE FRIDAY NIGHT AND CONSIDERABLY MORE IN
THE SOUTHERN ZONES. HEAVY RAIN WILL CONTINUE TO FALL SATURDAY AND
SATURDAY NIGHT IN NORTHERN GLACIER BAY...ZONE 28...AND ZONE 29.

RIGHT NOW...NO SNOWFALL EXPECTED AT LOW ELEVATIONS BUT 1 TO 3
INCHES IS LIKELY ALONG THE KLONDIKE HIGHWAY.

.AJK...WATCHES/WARNINGS/ADVISORIES
PUBLIC...WIND ADV...AKZ18 TODAY
         WIND ADV...AKZ17...22...23 FRI

MARINE...STORM...PKZ52 51 43
         GALE...PKZ42 41 22 21 33
         SCA...PKZ13 31 32 34 35 36

ABJ/FCF