Gale Warning 79, NWS Juneau, AK

SOUTHEAST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE JUNEAU AK
312 PM AKST FRI FEB 21 2014

.SHORT TERM...CLOUD COVER TODAY A BIT MORE THAN ORIGINALLY
EXPECTED BUT SNOW SHOWERS PANNED OUT AS EXPECTED FOR THE MOST
PART. A FRONT APPROACHING FROM THE WEST WILL STILL GRAZE THE
SOUTHWESTERN OUTER COAST, BUT THE ASSOCIATED CLOUD SHIELD IS VERY
RAGGED ON SATELLITE IMAGERY. STILL CALLING FOR CHANCE POPS FOR
RAIN AND SNOW OVER PRINCE OF WALES ISLAND LATER THIS AFTERNOON
AND EVENING. AFTER THAT...CLEARING SKIES AND DRY WEATHER FOR
SATURDAY COURTESY OF A BUILDING SURFACE HIGH OVER WESTERN CANADA
AND ASSOCIATED OUTFLOW WINDS ACROSS SOUTHEAST ALASKA.

 STRONGEST WINDS TOMORROW OUT OF THE USUAL SPOTS WHEN A STRONG
NORTHEAST OUTFLOW SCENARIO SETS UP. HAVE STRONG WIND HEADLINES
FOR SKAGWAY, FOR HAINES ALONG THE CHILKAT PENINSULA, AND FOR
JUNEAU NEAR LYNN CANAL AND THE DOWNTOWN AREA. FEEL PRETTY
CONFIDENT THAT THE SITUATION WILL NOT ESCALATE INTO A HIGH WIND
EVENT. IN THE MARINE ZONES, SOLID GALES FOR NORTHERN AND SOUTHERN
LYNN CANAL AND VERY STRONG GUSTS OUT OF TAKU INLET AND VARIOUS
OTHER INTERIOR PASSES FOR STEPHENS PASSAGE. ALSO HAVE GUSTS TO
55 KTS OUT OF DISENCHANTMENT BAY. WILL LIKELY SEE 40 KT GUSTS
DOWN THE STIKINE RIVER DELTA. AND EASTERLY PORTIONS OF SUMNER
STRAIT.

 VERY COLD NEAR SURFACE AIR WILL ARRIVE WITH THE ARCTIC FRONT
TONIGHT AND BOTTLE UP ALONG THE CANADA SIDE OF THE COAST
MOUNTAINS. COLDEST TEMPS WILL BE NEAR THE WINDY INTERIOR PASSES
AS WELL AS NEAR THE BORDER ALONG BOTH THE HAINES AND KLONDIKE
HIGHWAYS. NO WIND CHILL ADVISORIES WITH THE AFTERNOON SHORT RANGE
FORECAST, BUT LOOK FOR VALUES DOWN TO 25 DEGREES BELOW ZERO IN
SOME SPOTS.

 USED A BLEND OF ECMWF AND GEM FOR WIND DIRECTIONS OVER THE GULF
AND NORTHEASTERLY PRESSURE GRADIENT ALONG THE COAST MOUNTAINS.
ECMWF TONED TOWN THE STRENGTH OF THE GRADIENT BEING DEPICTED IN
GEM AND GEM MODERATED THE ANOMALOUS HIGH THAT IS USUALLY DEPICTED
NORTH OF YAKUTAT. USED HIGH RESOLUTION NAM FOR WIND SPEEDS OVER
THE GULF TO BETTER DEPICT OUTFLOW PLUMES ALONG THE OUTER COAST.
POP AND QPF NO FACTOR IN THE SHORT RANGE. OVERNIGHT LOWS FROM
BIAS CORRECTED MOS. DAYTIME HIGHS FROM BIAS CORRECTED NAM.
FORECAST CONFIDENCE IS ABOVE AVERAGE.

.LONG TERM...UPPER RIDGE WILL CLOSE OFF TO AN UPPER HIGH OVER ERN
INTERIOR AK BY LATE SAT NIGHT...THEN DRIFT E INTO THE YUKON BY
SUN NIGHT. A NEW RIDGE WILL BUILD TO THE E OF THE AREA EARLY NEXT
WEEK AND MERGE WITH THE UPPER HIGH OVER THE YUKON BY TUE. THE
RIDGE MAY BECOME A CLOSED OFF HIGH AGAIN OVER INTERIOR AK BY LATE
NEXT WEEK. A SFC HIGH WILL BUILD OVER NW CANADA THRU SAT
NIGHT...THEN REMAIN THERE THRU MUCH OF THE NEXT WEEK ALTHOUGH IT
MAY WEAKEN SOME. A SHORTWAVE TROF WILL MOVE S OF THE AREA SAT
NIGHT. A SERIES OF WEAKENING SHORTWAVE TROFS AND SFC FRONTS WILL
MOVE NW THRU THE GULF NEXT WEEK. USED BLEND OF 12Z GEM AND ECMWF
THRU MON...THEN BLENDED IN OR USED LATEST WPC FIELDS FOR THE
REMAINING PERIODS.

FOR SAT NIGHT...COLDER AIR WILL CONTINUE S INTO THE AREA BEHIND
DEPARTING SHORTWAVE. INCREASING N-NE PRESSURE GRADIENTS WILL
INCREASE WINDS OVER MUCH OF THE AREA ESPECIALLY THRU THE MTN
PASSES AND THE MORE CHANNELED TERRAIN. SKIES SHOULD BE OR BECOME MAINLY
CLEAR AS WELL. THIS WILL ALLOW FOR LARGE TEMP DIFFERENCES BETWEEN
THE WIND SHELTERED AREAS AND WINDY LOCATIONS.

FOR SUN THRU MON...STRONG OFFSHORE FLOW WILL CONTINUE. TEMPS WILL
SLOWLY MODERATE AS WARMER AIR ALOFT MOVES IN. SHOULD STILL BE
MAINLY CLEAR OVER THE AREA AS WELL.

AFTER MON...WITH SEVERAL WEAKENING SYSTEMS MOVING NW THRU THE
GULF...DECIDED TO BRING IN MORE CLOUDS TO THE SRN INNER CHANNELS
AND SRN HALF OF THE OUTER COAST AS THESE SYSTEMS MAY JUST BRUSH THAT
AREA. THESE SYSTEMS WILL ALSO HELP KEEP FAIRLY STRONG OFFSHORE
FLOW GOING...AND ALSO INCREASE WINDS OVER MUCH OF THE GULF. TEMPS
SHOULD CONTINUE TO MODERATE SOME THRU MIDWEEK...BUT LARGE DIURNAL
RANGES ARE LIKELY ESPECIALLY IN THE WIND SHELTERED AREAS.

.AJK WATCHES/WARNINGS/ADVISORIES...
PUBLIC...STRONG WIND FROM SATURDAY MORNING THROUGH SATURDAY AFTERNOON FOR
     AKZ018-019-025.
MARINE...GALE WARNING FOR PKZ012-013.
         SMALL CRAFT ADVISORY FOR PKZ011-021-022-031-032-034>036-041>043-
     051>053.

&&

FRITSCH/RWT