Gale Warning 585, NWS Anchorage, AK

897 
FZAK62 PAFC 292341
OFFALU

OFFSHORE WATERS FORECAST
NATIONAL WEATHER SERVICE ANCHORAGE AK
341 PM AKDT WED OCT 29 2014

OFFSHORE WATERS FORECAST FOR THE BERING SEA

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.

PKZ499-301430-
341 PM AKDT WED OCT 29 2014
.SYNOPSIS FOR CENTRAL BERING SEA...
A WEATHER FRONT OVER THE CENTRAL BERING SEA WILL GRADUALLY WEAKEN
THROUGH TONIGHT AS IT MOVES TO THE EASTERN BERING. A DEVELOPING
NORTH PACIFIC LOW WILL RAPIDLY STRENGTHEN TO 980 MB AS IT MOVES
TO NEAR 51N 179W THU MORNING. THE LOW WILL THEN MOVE TO NEAR 57N
165W AT 966 MB FRI AFTERNOON.

$$

PKZ411-301430-
BERING SEA OFFSHORE WEST OF 180 AND EAST OF THE INTERNATIONAL
DATELINE-
341 PM AKDT WED OCT 29 2014

...GALE WARNING THURSDAY NIGHT...

.TONIGHT...VARIABLE WIND 15 KT BECOMING SE WIND 10 TO 25 KT BY
MIDNIGHT. SEAS 8 TO 12 FT.
.THU...E WIND 20 TO 30 KT...BECOMING NW 30 KT S OF 56N IN THE
AFTERNOON. SEAS 9 TO 14 FT. RAIN SHOWERS.
.THU NIGHT...NW WIND 25 TO 40 KT...EXCEPT NE WIND 30 KT N OF 56N.
SEAS 9 TO 17 FT. RAIN.
.FRI...N WIND 15 TO 30 KT. SEAS 10 TO 18 FT.
.FRI NIGHT...N WIND 10 TO 20 KT. SEAS 13 TO 16 FT.
.SAT THROUGH SUN...W WIND 15 TO 30 KT. SEAS 8 TO 13 FT.
.MON...S WIND 15 TO 30 KT. SEAS 7 TO 12 FT.

$$

PKZ412-301430-
BERING SEA OFFSHORE 171W TO 180 AND NORTH OF 56N-
341 PM AKDT WED OCT 29 2014

...STORM WARNING THURSDAY NIGHT...

.TONIGHT...VARIABLE WIND 15 KT BECOMING S WIND 10 TO 20 KT BY
MIDNIGHT. SEAS 7 TO 12 FT. PATCHY FOG. RAIN AND SNOW.
.THU...E WIND 10 TO 25 KT INCREASING TO 30 TO 45 KT IN THE
AFTERNOON. SEAS 8 TO 12 FT BUILDING TO 19 FT IN THE AFTERNOON.
PATCHY FOG.
.THU NIGHT...NE WIND 40 TO 55 KT. SEAS 15 TO 21 FT. RAIN AND
SNOW.
.FRI...NE WIND 25 TO 40 KT. SEAS 16 TO 21 FT.
.FRI NIGHT...N WIND 20 TO 30 KT. SEAS 12 TO 17 FT.
.SAT THROUGH SUN...NW WIND 25 KT. SEAS 9 TO 14 FT.
.MON...SW WIND 10 TO 25 KT. SEAS 7 TO 10 FT.

$$

PKZ413-301430-
BERING SEA OFFSHORE 171W TO 180 AND SOUTH OF 56N-
341 PM AKDT WED OCT 29 2014

...STORM WARNING THURSDAY NIGHT...

.TONIGHT...SE WIND 30 KT BECOMING VARIABLE WIND UP TO 15 KT AFTER
MIDNIGHT. SEAS 8 TO 12 FT. PATCHY FOG.
.THU...E WIND 10 TO 25 KT BECOMING SE 30 TO 45 KT IN THE
LATE MORNING. SEAS 7 TO 12 FT BUILDING TO 19 FT IN THE AFTERNOON.
PATCHY FOG. RAIN.
.THU NIGHT...SW WIND 35 TO 50 KT. SEAS 13 TO 21 FT. RAIN.
.FRI...NW WIND 35 TO 50 KT. SEAS 15 TO 25 FT.
.FRI NIGHT...N WIND 10 TO 25 KT. SEAS 13 TO 17 FT.
.SAT THROUGH SUN...NW WIND 15 TO 30 KT. SEAS 10 TO 13 FT.
.MON...SW WIND 15 TO 30 KT. SEAS 9 TO 12 FT.

$$

PKZ414-301430-
BERING SEA OFFSHORE EAST OF 171W-
341 PM AKDT WED OCT 29 2014

...GALE WARNING THURSDAY NIGHT...

.TONIGHT...SE WIND 10 TO 25 KT. SEAS 6 TO 9 FT. PATCHY FOG.
.THU...E WIND 10 TO 20 KT INCREASING TO 15 TO 30 KT LATE MORNING.
SEAS 6 TO 10 FT. PATCHY FOG.
.THU NIGHT...SE WIND 30 TO 45 KT...BECOMING W 30 KT S OF 56 N
AFTER MIDNIGHT. SEAS 7 TO 12 FT BUILDING TO 12 TO 18 FT AFTER
MIDNIGHT. PATCHY FOG. RAIN AND SNOW.
.FRI...NE WIND 30 TO 45 KT. SEAS 13 TO 21 FT.
.FRI NIGHT...N WIND 20 TO 35 KT. SEAS 11 TO 18 FT.
.SAT THROUGH MON...NW WIND 15 TO 30 KT. SEAS 7 TO 12 FT.

$$

SOUTHCENTRAL AND SOUTHWEST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE ANCHORAGE AK
202 PM AKDT TUE OCT 28 2014

.ANALYSIS AND UPPER LEVELS...

500MB...A STACKED LOW CENTER WAS LOCATED NEAR THE AK PEN WITH A
SECONDARY CENTER OVER HAIDA GWAII. A RIDGE EXTENDED WEST FROM THE
CANADIAN YUKON TO OVER THE CENTRAL MAINLAND. A HIGH AMPLITUDE
RIDGE WAS OVER THE BERING SEA WITH A TROUGH TO THE WEST NEAR THE
KAMCHATKA PEN.

THE LOW NEAR THE AK PEN WEAKENS AS MOVES SOUTHEAST THEN EAST TO
OVER THE PANHANDLE THU AFTERNOON. AT THAT TIME...A BROAD TROUGH
EXTENDS SOUTH ACROSS MUCH OF THE MAINLAND. THE CENTRAL BERING SEA
RIDGE MOVES TO THE EASTERN BERING WITH A HIGH CENTER PINCHING OFF
NEAR THE CHUKCHI SEA THU AFTERNOON. THE KAMCHATKA TROUGH ELONGATES
EAST AS A DEVELOPING CENTER MOVES OVER THE EASTERN ALEUTIANS THU
EVENING. AT THAT TIME...A BROAD WESTERLY JET SETS UP OVER THE
NORTH PACIFIC.

SURFACE...
WIDESPREAD STRATUS WITH AREAS OF FOG AND FLURRIES CONTINUED OVER
THE COPPER RIVER BASIN. OUTFLOW WINDS WERE EVIDENT ALONG THE NORTH
GULF COAST AS WELL AS THE MATANUSKA VALLEY. VISIBLE SATELLITE
IMAGERY SHOWED SILT BLOWING OUT OF THE COPPER RIVER DELTA TO OVER
THE COASTAL WATERS.

FURTHER WEST...A SURFACE LOW NEAR THE AK PEN AND ASSOCIATED
FRONTAL TROUGH BROUGHT RAIN AND SNOW TO THE SOUTHWEST MAINLAND
AND RAIN/SHOWERS TO THE AK PEN. STRONG NORTHERLY WINDS WERE ALSO
PRESENT TO THE WEST OF THE CENTER FROM THE AK PEN TO THE CENTRAL
ALEUTAINS. WINDS OVER THE WESTERN ALEUTIANS SHIFTED TO THE
SOUTHEAST AS A FRONTAL TROUGH MOVED TO THE WESTERN BERING SEA THIS
MORNING.

&&

.MODEL DISCUSSION...
MODEL AGREEMENT VARIES DEPENDING ON AREA. THE ECMWF AND GFS ARE IN
FAIRLY GOOD AGREEMENT ON THE SYNOPTIC FEATURES OVER THE BERING
SEA AND ALEUTAINS...ESPECIALLY THE DEVELOPING LOW WHICH MOVES TO
THE CENTRAL ALEUTIANS THU. AFTERNOON PACKAGES IN THIS REGION WILL
BE BASED IN PART ON THE GFS.

FURTHER EAST...THE GEM REGION HAS A FAIRLY GOOD HANDLE ON
PRESSURE GRADIENTS ALONG THE NORTH GULF COAST AND DID A GOOD JOB
OF CAPTURING OUTFLOW WINDS THIS MORNING. THE ECMWF HAS THE OVER
ALL BEST SYNOPTIC HANDLING OF FEATURES AND WILL USED IN
COMBINATION WITH THE GEM REGIONAL.

&&

.SHORT TERM FORECAST...

SOUTHCENTRAL ALASKA...A WAVE MOVING ACROSS THE COPPER RIVER
TONIGHT WILL LIKELY STILL KICK OFF A FEW AREAS OF LIGHT
SNOW/FLURRIES. THIS WAVE WILL DO LITTLE TO BREAK UP THE
STRATUS...BUT MAY PRODUCE ENOUGH MIXING TO RAISE CEILINGS SOME
OVER THE EASTERN BASIN. OUTFLOW WIND ACROSS THE GULF SHOULD
DIMINISH SOME OVERNIGHT AS PRESSURE GRADIENTS WEAKEN AND
SUPPORTING FLOW ALOFT BECOMES LESS FAVORABLE. A WAVE MOVING NORTH
INTO THE NORTHER GULF ON WED AFTERNOON WILL BRING CLOUDS AND SOME
RAIN TO THE GULF COAST...BUT SHOULD NOT MAKE IT INLAND OVER THE
COASTAL/CHUGACH RANGES. SHOWERS SHOULD CONTINUE ALONG THE GULF
COASTS THROUGH THU.

SOUTHWEST ALASKA...

STRONG NORTHERLY WINDS ACROSS THE AK PEN WILL SLOWLY DIMINISH ON
WED. RAIN AND SNOW OVER SW ALASKA WILL MOVE SOUTH AND WEST WITH
THE FRONTAL BOUNDARY OVERNIGHT. DRY NORTHERLY FLOW WILL THEN TAKE
HOLD WED AND PERSIST THROUGH THU. A DEVELOPING LOW AND FRONTAL
TROUGH MOVING ACROSS THE ALEUTIANS WILL LIKELY BRING INCREASED
CHANCES OF RAIN TO THE AK PEN THU EVENING AND SNOW TO THE BRISTOL
BAY COAST FRI. WINDY CONDITIONS WILL ALSO ACCOMPANY THE
PRECIPITATION.

BERING SEA/ALEUTIANS...MOST OF THE AREA IS ON THE BACKSIDE OF THE
LOW PRESSURE SYSTEM UNDER WEAK COLD ADVECTION ALOFT. GALE FORCE
WINDS EXTEND FROM THE CENTRAL TO EASTERN BERING SEA ALONG WITH
RAIN AND SNOW SHOWERS. WINDS WILL SLOWLY TAPER FROM WEST TO EAST
BETWEEN NOW AND WEDNESDAY AFTERNOON. A DEVELOPING LOW OVER THE
NORTH PACIFIC MOVES TO THE CENTRAL ALEUTIANS THU AFTERNOON AND
SOUTH OF THE PRIBILOF'S THU NIGHT. EXPECT GALES IN ADVANCE OF
THIS SYSTEM WITH WESTERLY STORMS ALONG ITS SOUTHERN FLANK.

&&

.LONG TERM FORECAST...
MODEL AGREEMENT CONTINUES TO INCREASE WITH A SLIGHTLY FASTER LOW
TRACK FROM THE EASTERN BERING INTO THE GULF LATE FRIDAY OR EARLY
SATURDAY. THIS SYSTEM WILL BRING RAINY AND STORMY WEATHER TO THE
GULF COAST STARTING ON FRIDAY THAT NOW APPEARS TO PERSIST INTO
EARLY NEXT WEEK. THERE HAS ALSO BEEN A TREND TOWARDS A WETTER
FORECAST FOR SOUTHCENTRAL FOR SUNDAY AND MONDAY AS THE UPPER
TROUGH STALLS OVER THE SOUTHERN GULF. IT IS TOO SOON TO TELL HOW
THIS MAY IMPACT SOUTHCENTRAL...BUT THE MODELS ARE STARTING TO SHOW
ENOUGH COLD AIR ALOFT BY SUNDAY OR MONDAY TO SUPPORT SNOW AROUND
THE ANCHORAGE BOWL. EXACTLY WHEN AND HOW MUCH WILL BECOME A FOCUS
IN THE FORECAST LATER THIS WEEK.

THE MODELS THEN CONTINUE THE STORMIER PATTERN AS A DEEP LOW
CENTERED NEAR EASTERN SIBERIA WILL MOVE THROUGH THE BERING AND
POSSIBLY ONTO THE MAINLAND BY THE MIDDLE OF NEXT WEEK.

AFC WATCHES/WARNINGS/ADVISORIES...
PUBLIC...NONE.
MARINE...GALE 150 155 165 170 171 172 173 174.
FIRE WEATHER...NONE.

RMC/DEK OCT 14