Gale Warning 3, NWS Anchorage, AK

098 
FZAK61 PAFC 021243
OFFAER

OFFSHORE WATERS FORECAST
NATIONAL WEATHER SERVICE ANCHORAGE AK
343 AM AKST FRI JAN 2 2015

OFFSHORE WATERS FORECAST FOR THE GULF OF ALASKA WEST OF 144W

WIND FORECASTS REFLECT THE PREDOMINANT SPEED AND DIRECTION
EXPECTED. SEA FORECASTS REPRESENT AN AVERAGE OF THE HIGHEST
ONE-THIRD OF THE COMBINED WIND WAVE AND SWELL HEIGHT.

PKZ399-030215-
343 AM AKST FRI JAN 2 2015
.SYNOPSIS FOR THE WESTERN GULF OF ALASKA...

WEAK LOW PRESSURE WILL LINGER OVER THE NORTHERN GULF THROUGH
TONIGHT...THEN HIGH PRESSURE BUILDS OVER THE GULF THROUGH LATE SAT
NIGHT.

$$

PKZ351-030215-
GULF OF ALASKA OFFSHORE NORTH OF 57N AND WEST OF 144W-
343 AM AKST FRI JAN 2 2015

.TODAY...NW WIND 15 TO 30 KT DIMINISHING TO UP TO 20 KT IN THE
AFTERNOON. SEAS 7 TO 12 FT.
.TONIGHT...NW WIND UP TO 15 KT BECOMING NE 10 TO 25 KT AFTER
MIDNIGHT. SEAS 6 FT.
.SAT...E WIND 20 TO 30 KT. SEAS 5 TO 10 FT.
.SAT NIGHT...NE WIND 15 TO 30 KT. SEAS 7 TO 11 FT.
.SUN...N WIND 10 TO 25 KT. SEAS 6 TO 11 FT.
.MON THROUGH TUE...E WIND 15 TO 25 KT. SEAS 8 TO 12 FT.

$$

PKZ352-030215-
GULF OF ALASKA OFFSHORE SOUTH OF 57N NORTH OF 55N AND WEST OF
144W-
343 AM AKST FRI JAN 2 2015

.TODAY...NW WIND 15 TO 30 KT DIMINISHING TO 10 TO 20 KT IN THE
AFTERNOON. SEAS 8 TO 13 FT.
.TONIGHT...NW WIND 10 TO 15 KT. SEAS 7 FT.
.SAT...N WIND 10 TO 20 KT BECOMING NE 15 TO 30 KT IN THE
AFTERNOON. SEAS 6 TO 10 FT.
.SAT NIGHT...NE WIND 20 TO 30 KT. SEAS 7 TO 12 FT.
.SUN THROUGH TUE...E WIND 15 TO 25 KT. SEAS 9 TO 14 FT.

$$

SOUTHCENTRAL AND SOUTHWEST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE ANCHORAGE AK
511 AM AKST THU JAN 1 2015

.ANALYSIS AND UPPER LEVELS...
THE PATTERN TRANSITION IS UNDERWAY EARLY THIS MORNING AS THE LAST
VESTIGES OF THE PROLONGED EASTERN BERING SEA TROUGH ARE MOVING
INTO THE GULF. A PRETTY IMPRESSIVE BASAL WAVE IS SUPPORTING A
COMPACT CIRCULATION AT THE SURFACE WITH A TIGHT GALE FORCE WIND
FIELD. THE REST OF THE UPPER TROUGH IS FALLING APART WITH SHOWERS
DISSIPATING PRETTY QUICKLY. UPPER LEVEL MOISTURE ASSOCIATED WITH
THE GULF SYSTEM ENCOMPASSING MOST OF THE NORTH GULF COAST WITH
SOME RAIN SHOWING UP ON THE MIDDLETON ISLAND RADAR. THE SLACKENING
OF THE SOUTHEAST FLOW AND RECENT LOW LEVEL MOISTURE IS PROMOTING
FOG AND LOW STRATUS IN THE COOK INLET REGION AS WELL AS THE
SOUTHWEST MAINLAND. TEMPERATURES HAVE ALSO FALLEN BACK TOWARD
FREEZING WITH THE TRANSITION TO NORTHERN FLOW. THE ONLY OTHER
MAJOR FEATURE IS A FRONT TRACKING ACROSS THE BERING SEA ASSOCIATED
WITH A KAMCHATKA LOW.

&&

.MODEL DISCUSSION...
GUIDANCE REMAINS IN GOOD AGREEMENT EVEN WITH THE CHANGE OF FLOW
PATTERN ALOFT. THE CONSENSUS WITH THE DEVELOPING GULF LOW IS A
HARD EASTWARD TURN AFTER THE SYSTEM MATURES. THIS WILL KEEP MOST
OF THE PRECIPITATION OUT OF THE SOUTHCENTRAL. AS THE SYSTEM
WEAKENS A LINGERING TROUGH WILL SIT ALONG THE NORTH GULF COAST.
IN TERMS OF THE SYNOPTIC PATTERN...GUIDANCE STAYS IN LOCKSTEP
WITH EACH OTHER FOR THE NEXT FEW DAYS BEFORE DEVELOPING SOME
SLIGHT POSITIONAL DIFFERENCES WITH A SYSTEM IN THE EASTERN GULF ON
SUNDAY...SIMILAR TO THE CURRENT SYSTEM.

&&

.SHORT TERM FORECAST SOUTHCENTRAL ALASKA (DAYS 1 AND 2)...

THE DEVELOPING LOW IN THE GULF IS IN THE PROCESS OF SWITCHING THE
OVERALL FLOW PATTERN ACROSS SOUTHERN ALASKA TO A
NORTHERLY/OFFSHORE DIRECTION. THIS LOW WILL MAKE LITTLE MORE THAN
A GLANCING BLOW TO OUR FORECAST AREA TODAY AS THE ONLY
PRECIPITATION WILL FALL OVER FAR SOUTHEASTERN SECTIONS OF THE
COPPER RIVER BASIN. THE MUCH LARGER AND MORE WIDESPREAD IMPACT
WILL BE THE OUTFLOW WIND EVENT NOW BEGINNING ACROSS THE REGION.
THE PRESSURE GRADIENTS AND LOW-LEVEL THERMAL GRADIENTS ARE
FAVORABLE FOR WINDS IN THE USUAL AREAS (THOMPSON
PASS...WHITTIER...SEWARD) TO JUMP SIGNIFICANTLY TODAY.
HOWEVER...WE LIKE TO SEE A STRONG MOVEMENT OF AN ARCTIC AIRMASS
INTO THE REGION TO REALLY THREATEN TO CREATE A WARNING-LEVEL
EVENT...AND THAT IS MISSING IN THIS CASE AS COLD ADVECTION IS SLOW
AND WEAK FOR MOST AREAS. SIMILARLY...THE UPPER LEVEL PATTERN IS
ALSO NOT CONDUCIVE TO HELPING THE WINDS GET EVEN STRONGER. WHAT
LITTLE UPPER SUPPORT THERE IS WOULD FAVOR THE EAST-WEST GAPS LIKE
WHITTIER/PASSAGE CANAL. FINALLY...THE SURFACE LOW MOVING THROUGH
THE GULF IS A BIT TOO FAR TO THE SOUTH AND EAST TO BE OPTIMAL FOR
OUR PREFERRED GAP WIND OUTFLOW EVENTS. ALL THIS TO SAY...WINDS IN
THE USUAL GAPS WILL COME UP SIGNIFICANTLY TODAY AND
TONIGHT...BEFORE SLOWLY TAPERING OFF DURING THE DAY FRIDAY.

FOR INLAND AREAS...FOG AND LOW CLOUDINESS HAVE DEVELOPED IN
RESPONSE TO A BIT OF RADIATIONAL COOLING OVERNIGHT COMBINED WITH
THE SIGNIFICANT MOISTURE ADDED TO THE LOWER ATMOSPHERE FROM THE
SNOWPACK MELTDOWN (AS WELL AS RAINFALL) IN MANY AREAS YESTERDAY.
THE INCREASING NORTHERLY WINDS WILL TRY TO MOVE THESE CLOUDS OUT
OF THE AREA TODAY...BUT WILL HAVE A HARD TIME OVERCOMING THE
BLOCKING OF THE MOUNTAINS. THUS EXPECT ANOTHER FAIRLY CLOUDY DAY
FROM ANCHORAGE UP TO THE MAT-SU BEFORE MORE SIGNIFICANT CLEARING
AND COOLING BEGIN TONIGHT.

BY FRIDAY NIGHT INTO SATURDAY THE REMNANTS OF THE CURRENT GULF LOW
WILL DRIFT WESTWARD ALONG THE NORTH GULF COAST...BRINGING A RETURN
OF SNOW SHOWERS TO COASTAL AREAS AS FAR WEST AS PRINCE WILLIAM
SOUND. INLAND AREAS WILL REMAIN DRY FOR THE FORESEEABLE
FUTURE...AND WILL SEE MORE SUN THAN HAS BEEN EXPERIENCED FOR THE
LAST FEW WEEKS.

&&

.SHORT TERM FORECAST SOUTHWEST ALASKA (THURSDAY AND FRIDAY)...

A WEAK UPPER LEVEL LOW SITUATED OVER THE KUSKOKWIM DELTA CONTINUES
TO SLOWLY SLIDE EAST THIS MORNING. THIS HAS RESULTED IN UPSLOPE
SNOW SHOWERS ALONG THE KILBUCK MOUNTAINS IN THE KUSKOKWIM DELTA
AND INCREASED CLOUD COVER FROM BETHEL EAST TOWARD THE KILBUCK
MOUNTAINS. AS THIS UPPER LOW DRIFTS EASTWARD...RIDGING WILL BEGIN
TO SET UP ACROSS SOUTHWEST ALASKA AND BRING AN END TO THE SNOW
SHOWERS THAT HAVE BEEN PERSISTENT OVER THE PAST SEVERAL DAYS. FOG
WILL BECOME A CONCERN DURING THE OVERNIGHT HOURS WITH LIGHT WINDS
AND CLEARING SKIES BEING CONDUCIVE FOR FOG DEVELOPMENT. THE
BRISTOL BAY AREA HAS SEEN DENSE FOG ACROSS MANY LOCATIONS
OVERNIGHT AND WILL LIKELY SEE A SIMILAR SET UP TONIGHT AND
POSSIBLY AGAIN FRIDAY NIGHT. A DECAYING FRONT PRESENTLY LOCATED
OVER THE EASTERN HALF OF THE BERING SEA WILL CONTINUE TO SLIDE
EASTWARD LATE TONIGHT AS THE RIDGE AXIS SHIFTS EASTWARD TOWARD THE
ALASKA MAINLAND. THIS WILL BRING SOME SHOWER ACTIVITY TO THE WEST
COAST OF ALASKA LATE TONIGHT AND FRIDAY...WITH INLAND LOCATIONS
REMAINING DRY. TEMPERATURES WILL REMAIN AT ABOVE NORMAL TEMPERATURES
THROUGH TOMORROW AFTERNOON BEFORE TEMPERATURES DROP TO NEAR NORMAL
TO SLIGHTLY BELOW NORMAL FRIDAY NIGHT.

&&

.SHORT TERM FORECAST BERING SEA/ALEUTIANS (THURSDAY AND FRIDAY)...

A DECAYING FRONTAL BAND EXTENDING FROM COLD BAY NORTHWESTWARD
TOWARD THE PRIBILOF ISLANDS AND FINALLY INTO THE NORTHERN BERING
SEA CONTINUES TO BRING 30 KT WINDS AND PERIODS OF RAIN TO THE
BERING SEA. THIS FRONTAL BAND IS EXPECTED TO CONTINUE TO SLOWLY
DISSIPATE THROUGH THE DAY TODAY BEFORE MOVING OVER THE WEST COAST
OF ALASKA. AT THE SAME TIME...A RAPIDLY DEEPENING LOW PUSHING OFF
THE KAMCHATKA COAST WILL DRIVE YET ANOTHER FRONT INTO THE BERING
SEA STARTING LATE THIS AFTERNOON. THE FRONT IS EXPECTED TO BRING
STORM FORCE WINDS (50 KT) TO THE WESTERN BERING SEA AND WESTERN
ALEUTIANS BEFORE PUSHING OVER THE CENTRAL ALEUTIANS FRIDAY NIGHT
WITH GALE FORCE WINDS UP TO 45 KT OBSERVED. A PERIOD OF UNUSUALLY
NICE WEATHER (F0R THIS TIME OF THE YEAR) WILL BE OBSERVED OVER
THE EASTERN HALF OF THE BERING SEA STARTING TONIGHT AS SKIES BEGIN
TO CLEAR AND WINDS BECOME LIGHT AS A WEAK RIDGE DEVELOPS IN THE
WAKE OF THE FRONT PUSHING ACROSS THE AREA THIS MORNING. THIS
PERIOD OF NICE WEATHER WILL BE SHORT-LIVED HOWEVER AS THE
AFOREMENTIONED FRONT ENTERING THE BERING SEA IS EXPECTED TO PUSH
ACROSS THE PRIBILOF ISLANDS STARTING LATE FRIDAY NIGHT.

&&

.LONG TERM FORECAST (SAT JANUARY 3 - WED JANUARY 7)...

ON SATURDAY...THERE WILL BE A CLOSED BLOCKING HIGH CENTERED OVER
THE BROOKS RANGE...WITH A CLOSED LOW IN THE GULF OF ALASKA. THE
PRESSURE GRADIENT OVER ALASKA WILL BE OFFSHORE...WITH HIGH
PRESSURE CENTERED OVER THE YUKON TERRITORY. THIS SHOULD ALLOW FOR
COLDER TEMPERATURES AND MUCH DRIER CONDITIONS. SNOW SHOWERS WILL
BE ROTATING AROUND THE LOW ACROSS THE GULF ON SATURDAY BEFORE THE
LOW SHIFTS EAST. SUNDAY AND MONDAY WILL SEE INCREASING INFLUENCE
OF THE DRY AND COLD HIGH PRESSURE WITH CLEARING SKIES AND
CONTINUED OFFSHORE FLOW. THEREAFTER...THE GLOBAL MODELS DIVERGE
WITH THE PLACEMENT AND BREAKDOWN OF THE BLOCKING HIGH OVER
ALASKA...AND EXACTLY HOW FAR WEST IT RETROGRADES. THE GFS IS MORE
BULLISH WITH REGARD TO THE BLOCKING STRENGTH...WHICH KEEPS THE
STORM TRACK SHUNTED SOUTH OF ALASKA THROUGH WEDNESDAY WHEREAS THE
ECMWF AND CANADIAN GLOBAL SIMULATE STRONGER SOUTHERLY FLOW AND
INCREASING MOISTURE RETURN FROM THE PACIFIC. THE FORECAST WILL
TAKE A CONSERVATIVE MIDDLE GROUND APPROACH GIVEN THE CHALLENGES
DYNAMICAL MODELS HAVE REGARDING THE BREAKDOWN OF BLOCKING
HIGHS...WHICH WILL HIGHLIGHT LARGELY DRY CONDITIONS THROUGH
TUESDAY WITH INCREASING PRECIPITATION CHANCES WEDNESDAY.

&&

.AFC WATCHES/WARNINGS/ADVISORIES...
PUBLIC...NONE.
MARINE...GALE 120 121 127-132 173 175 176 185.
         STORM 177 178.
FIRE WEATHER...NONE.

&&

SYNOPSIS AND MODEL DISCUSSION...MTL
SOUTHCENTRAL ALASKA...AD
SOUTHWEST ALASKA/BERING SEA/ALEUTIANS...MC
LONG TERM...AHSENMACHER