Gale Warning 129, NWS Juneau, AK

SOUTHEAST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE JUNEAU AK
634 AM AKST WED FEB 4 2015

.SHORT TERM...A WEAK FEATURE IS CAUSING LOW TO MID LEVEL CLOUDS
OVER THE SOUTHERN PANHANDLE AND YAKUTAT THIS MORNING. SOME PLACES
HAVE RECORDED A TRACE OF PRECIPITATION WITH THESE CLOUDS...SO A
FLURRY/SPRINKLE CANNOT BE RULED OUT...AND AROUND AN INCH OF NEW
SNOW IN HYDER. DRY AIR IS ADVECTING IN HOWEVER...SO THE CHANCE OF
PRECIP DROPS OUT BY TONIGHT AS DO THE CLOUDS.

HIGH PRESSURE WILL START TO BUILD OVER THE YUKON TODAY AND A LOW
IN THE NORTH PACIFIC WILL DEEPEN AS IT APPROACHES THE SOUTHERN
GULF THROUGH LATE TONIGHT. AS A RESULT THE PRESSURE GRADIENT
ACROSS THE PANHANDLE WILL INCREASE SIGNIFICANTLY WITH 998MB AT OUR
SOUTHERN BORDER AND 1023MB AT WHITE PASS BY THE END OF TONIGHT.
FOR THIS REASON HAVE CONTINUED WITH WINDS INCREASING TO STORM
FORCE FOR NORTHERN LYNN CANAL, GALE WARNINGS FOR THE REST OF THE
NORTHERN INNER CHANNELS, HIGH WIND WATCH FOR JUNEAU AND SKAGWAY,
STRONG WIND HEADLINES FOR HAINES AND YAKUTAT, AND MENTION OF
STRONG GUSTS OUT OF INTERIOR PASSES ELSEWHERE. AND THIS IS JUST
THE BEGINNING OF THE EVENT.

TIMING OF WHEN THE HIGH WIND WATCH/WARNING CRITERIA OF +60MPH
WILL BEGIN IS STILL A LITTLE UNCERTAIN...THINK THAT IT MAY TAKE A
LITTLE LONGER TO REACH THAT CRITERIA AT SKAGWAY THEN IN JUNEAU
SINCE JUNEAU WILL HAVE THE MOUNTAIN WAVE TO HELP IT BEGIN. BECAUSE
OF THIS TIMING UNCERTAINTY AND BECAUSE THE BEGINNING TIME IS ABOUT
24HRS AWAY STILL...HAVE OPTED TO LEAVE THE WATCH AS IS BUT DO
EXPECT AT LEAST JUNEAU TO BE UPGRADED TO A WARNING.

TEMPERATURES THIS MORNING ARE NOT QUITE AS COLD AS YESTERDAY
BECAUSE THERE WERE SOME CLOUDS OVERNIGHT. SUNSHINE TODAY WILL HELP
TEMPERATURES RECOVER...BUT DO NOT EXPECT THEM TO GET ALL THE WAY
UP TO WHERE THEY WERE YESTERDAY AS COLD ARCTIC AIR WILL ACCOMPANY
THE NORTH WINDS (CAA). THEREFORE EXPECT LOW TEMPERATURES IN THE
LOW TEENS TO SINGLE DIGITS AGAIN OVER THE NORTHERN AREAS. TO
COUNTER THIS...WINDY PLACES WILL NOT BE AS COLD AS PLACES BLOCKED
BY THE N-NE WIND BECAUSE OF MIXING. THIS CAN BE A BIG FORECASTING
CHALLENGE WITH MORE THAN A 10 DEGREE DIFFERENCE ACROSS A TOWN
(IE FROM A BOAT HARBOR TO INNER VALLEY). SO MOST PLACES HAVE A BIG
TEMPERATURE RANGE IN THE TEXT FORECAST FOR TONIGHT.

USED MAINLY THE NAM AND ECMWF FOR THEIR GOOD INITIALIZATION OF THE
PRESSURE FIELD. NUDGED THE WINDS WITH THE HI-RES NMM FOR BOTH WIND
SPEEDS OUT OF INTERIOR PASSES OVER THE GULF AND WIND DIRECTIONS
THROUGH THE INNER CHANNELS. FORECAST CONFIDENCE IS ABOVE AVERAGE.

.LONG TERM...MODELS REMAIN IN GENERAL AGREEMENT THROUGH FRIDAY FOR
A DEEPENING ARCTIC TROUGH MOVES SOUTH INTO NORTHWESTERN CANADA
WITH DRY COLD CONTINENTAL AIR MASS. REFRESHED THE INHERITED
FORECAST WITH THE ECMWF AND NAM12 FOR THEIR GOOD CONSENSUS THROUGH
FRIDAY. SURFACE HIGH CONTINUES TO BUILD OVER CANADIAN CONTINENT
AND LOW PRESSURE AREA MOVES INTO THE SOUTHEASTERN GULF. THE
RESULTANT OFFSHORE PRESSURE GRADIENT BECOMES SIGNIFICANTLY TIGHT
TO PRODUCE STRONG OUTFLOW WINDS ACROSS THE NORTHERN HALF OF THE
PANHANDLE. MAINTAINED HIGH WIND WATCH THROUGH LATE FRIDAY NIGHT
FOR SKAGWAY AND JUNEAU ZONES. WITH COLD ARCTIC AIR MASS...THE
OUTFLOW WINDS WILL LIKELY TO PRODUCE HEAVY FREEZING SPRAY OVER THE
NORTHERN INNER CHANNELS ALONG WITH STORM FORCE WINDS. TAKU WIND
SCENARIO MAY CONTINUE TOWARD THE WEEKEND FOR DOWNTOWN JUNEAU AND
DOUGLAS. USED THE WPC ENSEMBLE SOLUTIONS FOR THE REMAINING LONG
TERM AND MAINTAINED THE GENERAL FORECASTING TREND WITH INCREASING
CLOUDS AND POPS BY LATE WEEKEND INTO EARLY NEXT WEEK WITH A SLIGHT
WARMING TREND BY TUESDAY.

&&

.AJK WATCHES/WARNINGS/ADVISORIES...
PUBLIC...HIGH WIND WATCH FROM LATE TONIGHT THROUGH LATE FRIDAY NIGHT FOR
     AKZ018-025.
         STRONG WIND FROM LATE TONIGHT THROUGH FRIDAY AFTERNOON FOR
     AKZ017-019.
         STRONG WIND FROM 3 PM AKST THIS AFTERNOON THROUGH LATE TONIGHT
     FOR AKZ018.
         WIND CHILL ADVISORY FROM MIDNIGHT TONIGHT TO 9 AM AKST THURSDAY
     FOR AKZ018.
MARINE...HEAVY FREEZING SPRAY WARNING FOR PKZ012.
         STORM WARNING FOR PKZ012.
         GALE WARNING FOR PKZ011-013-022-031-032-053.
         SMALL CRAFT ADVISORY FOR PKZ021-033>036-041>043-051.

&&

FERRIN/AHN

VISIT US AT HTTP://WWW.WEATHER.GOV/JUNEAU

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE JUNEAU AK
1119 AM AKST WED FEB 4 2015

AKZ017>029-050900-
CAPE FAIRWEATHER TO CAPE SUCKLING COASTAL AREA-
TAIYA INLET AND KLONDIKE HIGHWAY-HAINES BOROUGH AND LYNN CANAL-
GLACIER BAY-EASTERN CHICHAGOF ISLAND-
SALISBURY SOUND TO CAPE FAIRWEATHER COASTAL AREA-
CAPE DECISION TO SALISBURY SOUND COASTAL AREA-
EASTERN BARANOF ISLAND AND SOUTHERN ADMIRALTY ISLAND-
JUNEAU BOROUGH AND NORTHERN ADMIRALTY ISLAND-
INNER CHANNELS FROM KUPREANOF ISLAND TO ETOLIN ISLAND-
DIXON ENTRANCE TO CAPE DECISION COASTAL AREA-
SOUTHERN INNER CHANNELS-MISTY FJORDS-
INCLUDING THE CITIES OF...YAKUTAT...SKAGWAY...HAINES...GUSTAVUS...
HOONAH...ELFIN COVE...PELICAN...SITKA...PORT ALEXANDER...ANGOON...
JUNEAU...PETERSBURG...WRANGELL...KAKE...CRAIG...KLAWOCK...
KETCHIKAN...METLAKATLA...HYDER
1119 AM AKST WED FEB 4 2015

...SIGNIFICANT WINTER WEATHER TO IMPACT SOUTHEAST ALASKA THROUGH
THIS WEEKEND...

COLD TEMPERATURES AND STRONG WINDS WILL CREATE NEAR BLIZZARD
CONDITIONS ALONG THE KLONDIKE HIGHWAY WITH BLOWING SNOW AND
DANGEROUS WIND CHILLS. VERY GUSTY OUTFLOW WINDS WILL REACH AS HIGH
AS 90 MPH IN DOWNTOWN JUNEAU AND DOUGLAS. LATEST MODEL GUIDANCE IS
ALSO INDICATING THE POTENTIAL FOR SIGNIFICANT SNOWFALL ACROSS
PORTIONS OF THE CENTRAL PANHANDLE AND HYDER THURSDAY NIGHT INTO
FRIDAY AND THEN OVER THE NORTHERN PANHANDLE INTO THE WEEKEND.
HOWEVER...IF LATEST MODEL TRENDS CONTINUE THE SIGNIFICANT SNOWFALL
ON FRIDAY COULD EXPAND NORTHWARD TO JUNEAU AND HOONAH.

STAY TUNED TO WEATHER.GOV/JUNEAU FOR THE LATEST
FORECASTS TO THIS DEVELOPING WINTER WEATHER SITUATION.

THIS STATEMENT WILL BE UPDATED BY MIDNIGHT AKDT TONIGHT.

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE JUNEAU AK
321 PM AKST WED FEB 4 2015

AKZ017>029-050900-
CAPE FAIRWEATHER TO CAPE SUCKLING COASTAL AREA-
TAIYA INLET AND KLONDIKE HIGHWAY-HAINES BOROUGH AND LYNN CANAL-
GLACIER BAY-EASTERN CHICHAGOF ISLAND-
SALISBURY SOUND TO CAPE FAIRWEATHER COASTAL AREA-
CAPE DECISION TO SALISBURY SOUND COASTAL AREA-
EASTERN BARANOF ISLAND AND SOUTHERN ADMIRALTY ISLAND-
JUNEAU BOROUGH AND NORTHERN ADMIRALTY ISLAND-
INNER CHANNELS FROM KUPREANOF ISLAND TO ETOLIN ISLAND-
DIXON ENTRANCE TO CAPE DECISION COASTAL AREA-
SOUTHERN INNER CHANNELS-MISTY FJORDS-
INCLUDING THE CITIES OF...YAKUTAT...SKAGWAY...HAINES...GUSTAVUS...
HOONAH...ELFIN COVE...PELICAN...SITKA...PORT ALEXANDER...ANGOON...
JUNEAU...PETERSBURG...WRANGELL...KAKE...CRAIG...KLAWOCK...
KETCHIKAN...METLAKATLA...HYDER
321 PM AKST WED FEB 4 2015

...SIGNIFICANT WINTER WEATHER TO IMPACT SOUTHEAST ALASKA THROUGH
THIS WEEKEND...

COLD TEMPERATURES AND STRONG WINDS WILL CREATE NEAR BLIZZARD
CONDITIONS ALONG THE KLONDIKE HIGHWAY WITH BLOWING SNOW AND
DANGEROUS WIND CHILLS. VERY GUSTY OUTFLOW WINDS WILL REACH AS HIGH
AS 90 MPH IN DOWNTOWN JUNEAU AND DOUGLAS. LATEST MODEL GUIDANCE IS
ALSO INDICATING THE POTENTIAL FOR SIGNIFICANT SNOWFALL ACROSS
PORTIONS OF THE CENTRAL PANHANDLE AND HYDER THURSDAY NIGHT INTO
FRIDAY AND THEN OVER THE NORTHERN PANHANDLE INTO THE WEEKEND.
HOWEVER...IF LATEST MODEL TRENDS CONTINUE THE SIGNIFICANT SNOWFALL
ON FRIDAY COULD EXPAND NORTHWARD TO JUNEAU AND HOONAH.

STAY TUNED TO WEATHER.GOV/JUNEAU FOR THE LATEST
FORECASTS TO THIS DEVELOPING WINTER WEATHER SITUATION.

THIS STATEMENT WILL BE UPDATED BY MIDNIGHT AKDT TONIGHT.