Storm Warning 171, NWS Anchorage, AK

000 
FZAK62 PAFC 271204
OFFALU

OFFSHORE WATERS FORECAST
NATIONAL WEATHER SERVICE ANCHORAGE AK
400 AM AKDT TUE OCT 27 2009

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.

PKZ499-280200-
400 AM AKDT TUE OCT 27 2009
.SYNOPSIS FOR CENTRAL BERING SEA...
A WEAK 1011 MB LOW WILL DISSIPATE NEAR 55N 163W TODAY. A TRANSIENT
RIDGE WILL BUILD AND MOVE ACROSS THE BERING THROUGH WED NIGHT. A
STRONG WESTERN PACIFIC LOW NEAR JAPAN WILL MOVE NEAR 53N 174E AT 973
MB WED NIGHT.
$$

PKZ411-280200-
BERING SEA OFFSHORE WEST OF 180 AND EAST OF THE INTERNATIONAL
DATELINE
400 AM AKDT TUE OCT 27 2009

...STORM WARNING WEDNESDAY...

.TODAY...S WIND 25 KT. SEAS 7 FT. PATCHY FOG. 
.TONIGHT...SE WIND 35 KT INCREASING TO 45 KT AFTER MIDNIGHT. SEAS
13 FT. PATCHY FOG. 
.WED...SE WIND 50 KT. SEAS 24 FT. RAIN.
.WED NIGHT...SE WIND 50 KT. SEAS 27 FT. 
.THU...SE WIND 45 KT. SEAS 27 FT. 
.FRI...SW WIND 40 KT. SEAS 23 FT. 
.SAT...S WIND 35 KT. SEAS 14 FT.  

$$

PKZ412-280200-
BERING SEA OFFSHORE 171W TO 180 AND NORTH OF 56N
400 AM AKDT TUE OCT 27 2009

...GALE WARNING WEDNESDAY...

.TODAY...NW WIND 15 KT. SEAS 5 FT. PATCHY FOG. 
.TONIGHT...E WIND 15 KT BECOMING SE 25 KT AFTER MIDNIGHT. SEAS 6 FT.
PATCHY FOG. 
.WED...SE WIND 30 KT INCREASING TO 40 KT IN THE AFTERNOON. SEAS
10 FT. PATCHY FOG. 
.WED NIGHT...SE WIND 45 KT. SEAS 17 FT. 
.THU...SE WIND 45 KT. SEAS 24 FT. 
.FRI...S WIND 40 KT. SEAS 22 FT. 
.SAT...S WIND 35 KT. SEAS 12 FT.  

$$

PKZ413-280200-
BERING SEA OFFSHORE 171W TO 180 AND SOUTH OF 56N
400 AM AKDT TUE OCT 27 2009

...GALE WARNING WEDNESDAY...

.TODAY...NW WIND 20 KT. SEAS 6 FT. PATCHY FOG. 
.TONIGHT...E WIND 15 KT BECOMING SE 30 KT AFTER MIDNIGHT. SEAS 7 FT.
PATCHY FOG. 
.WED...SE WIND 45 KT. SEAS 13 FT. PATCHY FOG. 
.WED NIGHT AND THU...SE WIND 45 KT. SEAS 21 FT. 
.FRI...SW WIND 30 KT. SEAS 19 FT. 
.SAT...S WIND 35 KT. SEAS 12 FT.  

$$

PKZ414-280200-
BERING SEA OFFSHORE EAST OF 171W
400 AM AKDT TUE OCT 27 2009

.TODAY...VARIABLE WIND 15 KT BECOMING N WIND 20 KT IN THE AFTERNOON.
SEAS 6 FT. 
.TONIGHT...N WIND 15 KT. SEAS 5 FT. PATCHY FOG. 
.WED...NE WIND 15 KT. SEAS 5 FT. PATCHY FOG. 
.WED NIGHT...E WIND 25 KT. SEAS 5 FT. 
.THU...E WIND 25 KT. SEAS 9 FT. 
.FRI...E WIND 15 KT. SEAS 9 FT. 
.SAT...S WIND 20 KT. SEAS 8 FT.  

$$

000 
FZAK62 PAFC 272300
OFFALU

OFFSHORE WATERS FORECAST
NATIONAL WEATHER SERVICE ANCHORAGE AK
400 PM AKDT TUE OCT 27 2009

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.

PKZ499-281400-
400 PM AKDT TUE OCT 27 2009
.SYNOPSIS FOR CENTRAL BERING SEA...

HIGH PRESSURE OVER THE CENTRAL BERING SEA WILL MOVE INTO THE EASTERN
BERING AND THE WEST COAST OF ALASKA WED. A 954 MB LOW NEAR 68N 160E
WILL WEAKEN TO 984 MB NEAR 54N 175W THU AFTERNOON. 

$$

PKZ411-281400-
BERING SEA OFFSHORE WEST OF 180 AND EAST OF THE INTERNATIONAL
DATELINE
400 PM AKDT TUE OCT 27 2009

...STORM WARNING WEDNESDAY AND WEDNESDAY NIGHT...

.TONIGHT...SE WIND 25 KT INCREASING TO 45 KT AFTER MIDNIGHT. SEAS 5
FT BUILDING TO 16 FT AFTER MIDNIGHT. 
.WED AND WED NIGHT...SE WIND 50 KT. SEAS 28 FT. RAIN. 
.THU...SE WIND 45 KT. SEAS 27 FT. 
.THU NIGHT...SW WIND 45 KT. SEAS 21 FT. 
.FRI...SW WIND 35 KT. SEAS 17 FT. 
.SAT...S WIND 35 KT. SEAS 14 FT. 
.SUN...W WIND 35 KT. SEAS 13 FT.  

$$

PKZ412-281400-
BERING SEA OFFSHORE 171W TO 180 AND NORTH OF 56N
400 PM AKDT TUE OCT 27 2009

...GALE WARNING WEDNESDAY AND WEDNESDAY NIGHT...

.TONIGHT...VARIABLE WIND 15 KT BECOMING SE 25 KT AFTER MIDNIGHT. 
SEAS 5 FT. 
.WED...SE WIND 30 KT INCREASING TO 40 KT IN THE AFTERNOON. SEAS 
10 FT. 
.WED NIGHT...SE WIND 45 KT. SEAS 17 FT. 
.THU AND THU NIGHT...SE WIND 45 KT. SEAS 24 FT. 
.FRI...S WIND 30 KT. SEAS 18 FT. 
.SAT...S WIND 35 KT. SEAS 13 FT. 
.SUN...SW WIND 30 KT. SEAS 11 FT.  

$$

PKZ413-281400-
BERING SEA OFFSHORE 171W TO 180 AND SOUTH OF 56N
400 PM AKDT TUE OCT 27 2009

...GALE WARNING WEDNESDAY AND WEDNESDAY NIGHT...

.TONIGHT...VARIABLE WIND 15 KT BECOMING SE 30 KT AFTER MIDNIGHT. 
SEAS 7 FT. 
.WED AND WED NIGHT...SE WIND 45 KT. SEAS 20 FT. 
.THU...SE WIND 45 KT. SEAS 21 FT. 
.THU NIGHT...S WIND 40 KT. SEAS 18 FT. 
.FRI...W WIND 20 KT. SEAS 10 FT. 
.SAT...S WIND 35 KT. SEAS 12 FT. 
.SUN...W WIND 25 KT. SEAS 9 FT.  

$$

PKZ414-281400-
BERING SEA OFFSHORE EAST OF 171W
400 PM AKDT TUE OCT 27 2009

.TONIGHT...N WIND 15 KT. SEAS 3 FT. 
.WED...NE WIND 15 KT. SEAS 3 FT. 
.WED NIGHT...E WIND 25 KT. SEAS 5 FT. 
.THU...E WIND 25 KT. SEAS 7 FT. 
.THU NIGHT...E WIND 20 KT. SEAS 6 FT. 
.FRI...VARIABLE WIND 10 KT. SEAS 4 FT. 
.SAT...S WIND 20 KT. SEAS 6 FT. 
.SUN...SE WIND 20 KT. SEAS 6 FT.  

$$

000 
FZAK62 PAFC 281206
OFFALU

OFFSHORE WATERS FORECAST
NATIONAL WEATHER SERVICE ANCHORAGE AK
400 AM AKDT WED OCT 28 2009

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.

PKZ499-290200-
400 AM AKDT WED OCT 28 2009
.SYNOPSIS FOR CENTRAL BERING SEA...
A TRANSIENT RIDGE OVER THE CENTRAL BERING WILL MOVE TOWARDS 
THE WEST COAST OF ALASKA WED.  A 954 MB LOW NEAR 50N 166E WILL
WEAKEN TO 994 MB NEAR 56N 176W THU NIGHT.
$$

PKZ411-290200-
BERING SEA OFFSHORE WEST OF 180 AND EAST OF THE INTERNATIONAL
DATELINE
400 AM AKDT WED OCT 28 2009

...STORM WARNING THROUGH TONIGHT...

.TODAY...SE WIND 50 KT. SEAS 24 FT. RAIN.
.TONIGHT...SE WIND 50 KT. SEAS 27 FT. RAIN.
.THU...SE WIND 45 KT. SEAS 26 FT. RAIN.
.THU NIGHT...SE WIND 40 KT. SEAS 21 FT. 
.FRI AND SAT...SW WIND 35 KT. SEAS 16 FT. 
.SUN...SW WIND 30 KT. SEAS 17 FT.  

$$

PKZ412-290200-
BERING SEA OFFSHORE 171W TO 180 AND NORTH OF 56N
400 AM AKDT WED OCT 28 2009

...GALE WARNING THROUGH THURSDAY...

.TODAY...E OF 175 W...SE WIND 20 KT INCREASING TO 30 KT IN THE
AFTERNOON. W OF 175 W...SE WIND 30 KT INCREASING TO 40 KT IN THE
AFTERNOON. SEAS 10 FT. 
.TONIGHT AND THU...SE WIND 40 KT. SEAS 13 FT BUILDING TO 17 FT. 
.THU...SE WIND 40 KT. SEAS 17 FT. 
.THU NIGHT AND FRI...SE WIND 35 KT. SEAS 16 FT SUBSIDING TO 12 FT. 
.SAT...S WIND 35 KT. SEAS 12 FT. 
.SUN...SW WIND 20 KT. SEAS 14 FT.  

$$

PKZ413-290200-
BERING SEA OFFSHORE 171W TO 180 AND SOUTH OF 56N
400 AM AKDT WED OCT 28 2009

...GALE WARNING THROUGH THURSDAY...

.TODAY...E OF 175 W...NE WIND 15 KT BECOMING SE IN THE AFTERNOON. W
OF 175 W...SE WIND 45 KT. SEAS 13 FT. 
.TONIGHT...E OF 175 W...SE WIND 30 KT. W OF 175 W...SE WIND 45 KT.
SEAS 17 FT. 
.THU...SE WIND 40 KT. SEAS 19 FT. RAIN.
.THU NIGHT...SE WIND 40 KT. SEAS 18 FT. 
.FRI...S WIND 30 KT. SEAS 14 FT. 
.SAT...S WIND 35 KT. SEAS 12 FT. 
.SUN...SW WIND 20 KT. SEAS 15 FT.  

$$

PKZ414-290200-
BERING SEA OFFSHORE EAST OF 171W
400 AM AKDT WED OCT 28 2009

.TODAY...NE WIND 15 KT. SEAS 5 FT. 
.TONIGHT AND THU...E WIND 20 KT. SEAS 8 FT. 
.THU NIGHT AND FRI...NE WIND 20 KT. SEAS 10 FT. 
.SAT...S WIND 20 KT. SEAS 10 FT. 
.SUN...W WIND 20 KT. SEAS 9 FT.  

$$

000 
FZAK62 PAFC 282301
OFFALU

OFFSHORE WATERS FORECAST
NATIONAL WEATHER SERVICE ANCHORAGE AK
400 PM AKDT WED OCT 28 2009

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.

PKZ499-291400-
400 PM AKDT WED OCT 28 2009
.SYNOPSIS FOR CENTRAL BERING SEA...

A 963 MB LOW NEAR 51N 169E WILL MOVE TO NEAR 55N 180 AND WEAKEN TO
1003 MB FRI AFTERNOON. HIGH PRESSURE OVER THE EASTERN BERING WILL
PERSIST THROUGH FRI. 

$$

PKZ411-291400-
BERING SEA OFFSHORE WEST OF 180 AND EAST OF THE INTERNATIONAL
DATELINE
400 PM AKDT WED OCT 28 2009

...GALE WARNING THROUGH THURSDAY NIGHT...

.TONIGHT...SE WIND 45 KT. SEAS 25 FT. RAIN. 
.THU...SE WIND 40 KT. SEAS 22 FT. RAIN.
.THU NIGHT...SE WIND 35 KT. SEAS 18 FT. RAIN.
.FRI...E WIND 30 KT. SEAS 15 FT. 
.FRI NIGHT...S WIND 25 KT. SEAS 10 FT. 
.SAT AND SUN...SW WIND 30 KT. SEAS 12 FT. 
.MON...SE WIND 20 KT. SEAS 9 FT.  

$$

PKZ412-291400-
BERING SEA OFFSHORE 171W TO 180 AND NORTH OF 56N
400 PM AKDT WED OCT 28 2009

...GALE WARNING THROUGH THURSDAY NIGHT...

.TONIGHT...SE WIND 35 KT. SEAS 12 FT. 
.THU AND THU NIGHT...SE WIND 35 KT. SEAS 15 FT. 
.FRI...SE WIND 30 KT. SEAS 13 FT. 
.FRI NIGHT...SE WIND 25 KT. SEAS 10 FT. 
.SAT...SE WIND 30 KT. SEAS 11 FT. 
.SUN...SW WIND 30 KT. SEAS 12 FT. 
.MON...W WIND 15 KT. SEAS 8 FT.  

$$

PKZ413-291400-
BERING SEA OFFSHORE 171W TO 180 AND SOUTH OF 56N
400 PM AKDT WED OCT 28 2009

...GALE WARNING THROUGH THURSDAY NIGHT...

.TONIGHT...SE WIND 40 KT. SEAS 15 FT. 
.THU...SE WIND 40 KT. SEAS 19 FT. 
.THU NIGHT...SE WIND 35 KT. SEAS 17 FT. 
.FRI...SE WIND 30 KT. SEAS 13 FT. 
.FRI NIGHT AND SAT...S WIND 25 KT. SEAS 10 FT. 
.SUN...W WIND 25 KT. SEAS 9 FT. 
.MON...S WIND 20 KT. SEAS 8 FT.  

$$

PKZ414-291400-
BERING SEA OFFSHORE EAST OF 171W
400 PM AKDT WED OCT 28 2009

.TONIGHT...NE WIND 20 KT. SEAS 5 FT. 
.THU...NE WIND 20 KT. SEAS 6 FT. 
.THU NIGHT...NE WIND 25 KT. SEAS 8 FT. 
.FRI AND FRI NIGHT...NE WIND 25 KT. SEAS 10 FT. 
.SAT...E WIND 20 KT. SEAS 8 FT. 
.SUN...SE WIND 25 KT. SEAS 9 FT. 
.MON...NW WIND 20 KT. SEAS 7 FT.  

$$

AREA FORECAST DISCUSSION
SOUTHCENTRAL AND SOUTHWEST ALASKA
500 AM AKDT MON OCT 26 2009

CORRECTION FOR TYPOS

.MODEL DISCUSSION...
OVERNIGHT...THE MODELS IN THE IMMEDIATE SHORT TERM WERE NOT
INITIALIZING WELL IN HANDLING A LOW MOVING TOWARDS YAKUTAT. ALL OF
THE MODELS SEEMED TO BE TOO FAST WITH WINDS THAT WERE GENERALLY
UNDERDONE. OUT WEST THE MODELS SEEMED TO HAVE A PRETTY GOOD HANDLE ON
A SERIES OF LOWS OVER THE BERING. THE OVERALL PACKAGE HAD HEAVY GFS
THROUGHOUT THE MAJORITY OF THE PACKAGE. BEYOND THE SHORT TERM ...
DIFFERENCES START TO DEVELOP...AND THOSE DETAILS ARE DISCUSSED IN THE
LONG TERM FORECAST BELOW.

.ANALYSIS AND UPPER LEVELS...
ALASKA REGION IS EMBEDDED WITHIN A HIGH AMPLITUDE LONG-WAVE TROUGH. A
WEAKENING UPPER LEVEL LOW OVER THE BERING IS DIPPING SOUTH. A
SHORTWAVE WEST OF THE KENAI PENINSULA IS WEAKENING AND A STRONG
VORT-MAX ON THE SOUTH SIDE OF THE LOW IS POISED TO EJECT OUT OF
THE CYCLONIC ROTATION INTO THE EASTERN BERING. AT THE SURFACE A
STACKED LOW NEAR YAKUTAT IS MOVING ONSHORE. MEANWHILE AN EAST - WEST
ORIENTED TROUGH EXTENDS TO THE WEST OF THE LOW THROUGH PRINCE WILLIAM
SOUND.  A SHORT-WAVE TROUGH AND LOW LEVEL ARCTIC FRONT ARE SLOWLY
PIVOTING OFF TO THE NORTHEAST RESULTING IN CONTINUED RAIN AND SNOW
SHOWERS ACROSS THE REGION. A CLOSED UPPER LOW CONTINUES TO DROP
SOUTHEASTWARD ACROSS THE CENTRAL BERING. MULTIPLE SURFACE LOWS HAVE
FORMED IN RESPONSE TO THE SHORT-WAVE ROTATING AROUND THE UPPER
CENTER.

.SHORT TERM FORECAST...
A WEAK LOW IN WESTERN PRINCE WILLIAM SOUND WILL BE DEVELOPING THIS
AFTERNOON. THIS LOW...COUPLED WITH COLD AIR ADVECTION AND AN
ADVANCING SHORTWAVE WILL HELP TO BRING SNOW TO THE ANCHORAGE AREA.
WHILE NOT AS IMPRESSIVE AS IT LOOKED YESTERDAY...SNOW WILL BE SEEN
ALONG TYPICAL UPSLOPE AREAS OF THE HILLSIDE TODAY. EVEN THOUGH THE
FREEZING LEVELS JUMPED CLOSE TO 1000 FEET OVERNIGHT...THE MID LEVELS
CONTINUE TO COOL ANYWHERE FROM 2 TO 4 DEGREES IN 12 HOURS. IT WILL
TAKE A WHILE TO COOL ANCHORAGE ENOUGH TO HAVE SNOW ACCUMULATE ... A
WINTERY MIX OF RAIN MIXING WITH SNOW WILL BE NOTED THROUGHOUT THE
DAY. THE BRUNT OF THE ENERGY ASSOCIATED WITH THE AFOREMENTIONED
VORT-MAX IS NOW FURTHER SOUTH AND EAST THAN LAST NIGHT...BRINGING
DOWN THE ACCUMULATION TOTALS TO AN INCH OR LESS. MID WEEK AN UPPER
LEVEL TROUGH WILL EXIT THE REGION LEADING TO A DRYING TREND ACROSS
SOUTHCENTRAL.

OUT WEST....THE SHORT-WAVE TROUGH SITTING OVER SOUTHWEST
ALASKA CONTINUES TO PIVOT NORTHEASTWARD ...RESULTING IN
CONTINUED AREAS OF LIGHT PRECIPITATION ALONG AND JUST AHEAD OF IT.
THE SHORT-WAVE TROUGH WILL COMPLETELY SHEAR APART TODAY AS THE STRONG
BERING SHORT-WAVE SHOOTS THROUGH THE AREA INTO THE GULF. WESTERLY LOW
LEVEL FLOW WILL INCREASE SO THAT AREAS OF LIGHT SNOW WILL LIKELY
PERSIST ALONG THE UPSLOPE OF THE ALASKA AND ALEUTIAN RANGES.
TEMPERATURES ALOFT WOULD APPEAR TO SUPPORT MAINLY SNOW ACROSS THE
REGION...BUT IT IS STILL EARLY IN THE SEASON AND SEA SURFACE
TEMPERATURES IN THE LOWER 40S ARE RESULTING IN A WARM MARINE LAYER
THEREFORE...EXPECT A MIX OF RAIN AND SNOW. RIDGE WILL BUILD IN BEHIND
THE LOW COMPLEX...PROVIDING A BRIEF BREAK IN THE WEATHER BEFORE A
MAJOR STORM FORCE LOW MOVES TO THE WESTERN BERING AND ALEUTIANS MID
WEEK.

.LONG TERM FORECAST...
THE LONG TERM GUIDANCE CONTINUES TO BE PLAGUED BY UNCERTAINTY. BEYOND
THURSDAY ... GLOBAL MODELS STRUGGLE WITH HOW TO HANDLE THE REMNANTS
OF TROPICAL STORM LUPIT IN THE WESTERN ALEUTIANS. THE LATEST RUNS OF
THE GFS FULLY DIVERGE FROM EACH OTHER WITH THE 25/12Z GFS DRIFTING
SOUTH OF THE ALEUTIAN CHAIN...THE 26/00Z GFS DRIFTING INTO THE BERING
AND THE 26/06Z GFS DRIFTING NORTH TOWARDS SHEMYA. THE GFS ALWAYS HAS
AN INHERENT PROBLEM OF BREAKING DOWN FAIRLY WELL ESTABLISHED RIDGES.
MEANWHILE THE ENSEMBLE MEAN GUIDANCE IS MUCH CLOSER TO THAT OF THE
LATEST 06Z SOLUTION...BUT THE INDIVIDUAL MEMBERS ARE ALL OVER...AND
THE 500MB HEIGHT ENSEMBLE STANDARD DEVIATION REMAINS MANY DEVIATIONS
BEYOND THE NORM...LEAVING LITTLE FAITH IN DETAILS. THE ECMWF HAS BEEN
A LITTLE MORE STABLE FROM RUN TO RUN...EVENTUALLY WORKING THE STORM
UP THE WESTERN PERIPHERY OF THE RIDGE ... TOWARDS SHEMYA BEFORE
DISSIPATING...SIMILAR TO THE LATEST GFS SOLN. PROBLEMS ARE NOT AS
EVIDENT OUT EAST AS THEY ARE IN THE WEST...BUT ALL BIG ISSUES ARE
DERIVED FROM THE INABILITY TO ACCURATELY DEAL WITH LUPIT. WHILE
CONFIDENCE IS SLOWLY INCREASING WITH A TREND TOWARDS STABLE
SOLNS...IT STILL REMAINS LOW BEYOND THE END OF THE WEEK.

.AER/ALU...WATCH/WARNING SUMMARY
PUBLIC...NONE
MARINE...130 132 136 141 150 155 170
FIRE WEATHER...NONE

SHEA OCT 09