Small Craft Advisory 150, NWS Juneau, AK

SOUTHEAST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE JUNEAU AK
235 PM AKST THU FEB 23 2012

.SHORT TERM...A LOW OVER THE NORTH PACIFIC WILL BE SLOWLY
DEEPENING (TO ABOUT 995 MB) AS IT MOVES EAST TO THE SOUTHERN TIP
OF HAIDA GWAII BY FRIDAY AFTERNOON. AS IT DOES AN INVERTED TROUGH
WILL DEVELOP ALONG THE COASTAL AREA OVER THE OUTER WATERS. THE
PRECIPITATION BAND WITH THE LOW WILL EXTEND TO JUST NORTH OF
DIXON ENTRANCE TO EFFECT THE SOUTHERN PORTION OF THE SOUTH TIER
OF PUBLIC ZONES.

 DURING THE EVENING A RESIDUAL LOW NEAR PRINCE WILLIAM SOUND WILL
SPIN SOME SHOWERS INTO THE WESTERN PORTION OF THE NORTHEAST GULF
COAST...MOST OF THE SHOWERS WILL BE WEST OF ICY BAY...THOUGH A
FEW FLURRIES MAY REACH THE YAKUTAT AREA.

 COOLER TEMPERATURES ALOFT CONTINUE TO SPREAD INTO THE SOUTHEAST
ALASKA PANHANDLE. THAT COMBINED WITH THE START OF SOME OFFSHORE
FLOW AND THEN CLEARING WILL ALLOW LOW TEMPERATURES TO FALL
ANOTHER COUPLE OF DEGREES TONIGHT ACROSS THE REGION.

 LOCALLY GUSTY SOUTH WINDS IN THE LYNN CANAL REGION WILL DO A
DIRECTIONAL SHIFT THIS EVENING TO THE NORTH OVERNIGHT. WINDS IN
THE CANAL THEN INCREASE TO GALE FORCE LATE IN THE AFTERNOON OVER
THE NORTHERN LYNN CANAL AREA.

 IN THE DOWNTOWN JUNEAU AREA THE START OF MOUNTAIN WAVE GUSTS TO
JUST SHY OF 40 MPH BY FRIDAY AFTERNOON.

 &&

 .LONG TERM...LONG RANGE PERIOD IS GENERALLY QUIET WITH ONLY A
FEW UPHEAVALS HERE AND THERE. FIRST MAIN CONCERN SHOWS UP RIGHT
AT THE START OF THE PERIOD FRI NIGHT WITH COLD OUTFLOW WINDS OVER
MOST OF THE NORTHERN HALF OF THE PANHANDLE. THE PARENT COLD HIGH
IN CANADA IS NOT VERY STRONG AND WILL NOT BE AROUND FOR LONG. IT
WILL BE PUSHED OFF TO THE EAST BY SUN. WHILE IT IS HERE THOUGH,
WINDS WILL BE BLOWING OUT OF THE USUAL OUTFLOW AREAS BUT WILL NOT
BE THAT STRONG AS MOST OF THE COLD AIR SHOULD BE STILL BOTTLED UP
IN CANADA BEING TOO SHALLOW TO MAKE IT OVER MOST OF THE MOUNTAIN
PASSES. STILL I AM FORECASTING GALES FOR LYNN CANAL MOSTLY DUE TO
THE PRESSURE GRADIENT. I AM ALSO LOOKING AT HIGHER WINDS FOR
DOWNTOWN JUNEAU AND DOUGLAS FRIDAY NIGHT AS CONDITIONS FOR A
MODERATE TAKU EVENT SEEM LIKELY.

 FARTHER OUT THE DRY WEATHER WILL COME TO AN END BY EARLY NEXT
WEEK AS AN APPROACHING FRONT PUSHES THE INVERTED TROUGH OVER THE
PANHANDLE AND THE RIDGE OVER THE GULF TO THE EAST. PRECIP LOOKS
LIKE IT WILL START UP EARLY MON WITH SOME WINDY CONDITIONS ALONG
THE OUTER COAST. THE AIR MASS WILL BE COLD ENOUGH THAT MOST
PLACES WILL START OUT AS SNOW WITH SOME PLACES STARTING TO MIX
WITH RAIN. MUCH OF THE REST OF THE LONG TERM PERIOD IS SPENT
DEALING WITH SHOWERS AS THE PARENT LOW OF THE FRONT REMAINS IN
THE NORTHERN GULF THROUGH THE REST OF THE WEEK.

 MODEL AGREEMENT IN THE MID RANGE WAS RATHER GOOD WITH ONLY SOME
MINOR DIFFERENCES STARTING TO SHOW UP FOR MONDAY. DECIDED TO DO A
BLEND OF NAM/EC/GFS IN THE MID RANGE THEN TRANSITIONING TO A
MOSTLY HPC BLEND FOR THE EXTENDED. FORECAST CONFIDENCE IS ABOUT
AVERAGE.

.AJK WATCHES/WARNINGS/ADVISORIES...
PUBLIC...NONE.
MARINE...GALE WARNING FOR PKZ012-041.
         SMALL CRAFT ADVISORY FOR PKZ011-013-021-022-031>036-042-043.
         SMALL CRAFT ADVISORY DUE TO SEAS FOR PKZ051-052.

&&

BEZENEK/EAL