Storm Warning 111, NWS Anchorage, AK

000 
FZAK62 PAFC 132356
OFFALU

OFFSHORE WATERS FORECAST
NATIONAL WEATHER SERVICE ANCHORAGE AK
400 PM AKDT MON APR 13 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.

PKZ499-141400-
400 PM AKDT MON APR 13 2009
.SYNOPSIS FOR CENTRAL BERING SEA...
A 990 MB LOW NEAR 54N 165W WILL MOVE TO NEAR 50N 150W WED AFTERNOON.
A 1000 MB LOW WILL FORM NEAR 53N 154W MON NIGHT AND MOVE TO 56N 156W
TUE EVENING AND DISSIPATE.

$$

PKZ411-141400-
BERING SEA OFFSHORE WEST OF 180 AND EAST OF THE INTERNATIONAL
DATELINE
400 PM AKDT MON APR 13 2009

.TONIGHT...E WIND 30 KT DIMINISHING TO 20 KT AFTER MIDNIGHT. SEAS
17 FT. 
.TUE...S WIND 25 KT. SEAS 12 FT. 
.TUE NIGHT...SW WIND 30 KT. SEAS 12 FT. RAIN AND SNOW SHOWERS. 
.WED...W WIND 30 KT. SEAS 10 FT. 
.WED NIGHT...SW WIND 20 KT. SEAS 9 FT. 
.THU...S WIND 30 KT. SEAS 8 FT. 
.FRI...S WIND 30 KT. SEAS 11 FT. 
.SAT...W WIND 15 KT. SEAS 10 FT.  

$$

PKZ412-141400-
BERING SEA OFFSHORE 171W TO 180 AND NORTH OF 56N
400 PM AKDT MON APR 13 2009

...GALE WARNING THROUGH TUESDAY...
...HEAVY FREEZING SPRAY WARNING THROUGH TUESDAY...

.TONIGHT...NE WIND 40 KT. SEAS 16 FT. HEAVY FREEZING SPRAY. 
.TUE...NE WIND 35 KT. SEAS 11 FT. HEAVY FREEZING SPRAY. 
.TUE NIGHT...N WIND 25 KT. SEAS 7 FT. SNOW SHOWERS. FREEZING SPRAY. 
.WED...W WIND 25 KT. SEAS 7 FT. 
.WED NIGHT...NW WIND 20 KT. SEAS 8 FT. 
.THU...W WIND 15 KT. SEAS 9 FT. 
.FRI AND SAT...S WIND 20 KT. SEAS 8 FT. 

$$

PKZ413-141400-
BERING SEA OFFSHORE 171W TO 180 AND SOUTH OF 56N
400 PM AKDT MON APR 13 2009

...GALE WARNING THROUGH TUESDAY...

.TONIGHT...NE WIND 45 KT. SEAS 19 FT. 
.TUE...NE WIND 45 KT DIMINISHING TO 35 KT IN THE AFTERNOON. 
SEAS 17 FT. 
.TUE NIGHT...N WIND 30 KT. SEAS 13 FT. 
.WED AND WED NIGHT...NW WIND 25 KT. SEAS 9 FT. 
.THU...W WIND 20 KT. SEAS 8 FT. 
.FRI AND SAT...S WIND 20 KT. SEAS 7 FT. 

$$

PKZ414-141400-
BERING SEA OFFSHORE EAST OF 171W
400 PM AKDT MON APR 13 2009

...STORM WARNING TONIGHT...
...HEAVY FREEZING SPRAY WARNING THROUGH TUESDAY...

.TONIGHT...NE WIND 50 KT. SEAS IN ICE FREE WATERS 17 FT. SNOW. 
HEAVY FREEZING SPRAY. 
.TUE...NE WIND 45 KT. SEAS IN ICE FREE WATERS 16 FT. 
HEAVY FREEZING SPRAY. 
.TUE NIGHT...N WIND 40 KT. SEAS IN ICE FREE WATERS 12 FT. 
FREEZING SPRAY. 
.WED AND WED NIGHT...NW WIND 25 KT. SEAS IN ICE FREE WATERS 8 FT. 
.THU...N WIND 20 KT. SEAS IN ICE FREE WATERS 6 FT. 
.FRI...NW WIND 20 KT. SEAS IN ICE FREE WATERS 6 FT. 
.SAT...SW WIND 15 KT. SEAS IN ICE FREE WATERS 4 FT. 

$$

000 
FZAK62 PAFC 141144
OFFALU

OFFSHORE WATERS FORECAST
NATIONAL WEATHER SERVICE ANCHORAGE AK
400 AM AKDT TUE APR 14 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.

PKZ499-150200-
400 AM AKDT TUE APR 14 2009
.SYNOPSIS FOR CENTRAL BERING SEA...

A 997 MB LOW NEAR 52N 167W WILL MOVE INTO THE WESTERN GULF OF ALASKA
THIS AFTERNOON. HIGH PRESSURE WILL BUILD OVER THE CENTRAL BERING TUE
NIGHT THROUGH THU MORNING. 

$$

PKZ411-150200-
BERING SEA OFFSHORE WEST OF 180 AND EAST OF THE INTERNATIONAL
DATELINE
400 AM AKDT TUE APR 14 2009

.TODAY...E WIND 15 KT BECOMING S 25 KT IN THE AFTERNOON. SEAS 16 FT.
.TONIGHT...S WIND 30 KT BECOMING SW 20 KT AFTER MIDNIGHT. SEAS 
13 FT. 
.WED...W WIND 25 KT. SEAS 10 FT. 
.WED NIGHT...SW WIND 20 KT. SEAS 8 FT. 
.THU AND FRI...S WIND 30 KT. SEAS 11 FT. 
.SAT...NE WIND 25 KT. SEAS 10 FT.  

$$

PKZ412-150200-
BERING SEA OFFSHORE 171W TO 180 AND NORTH OF 56N
400 AM AKDT TUE APR 14 2009

...HEAVY FREEZING SPRAY WARNING THROUGH TONIGHT...

.TODAY...NE WIND 30 KT. SEAS IN ICE FREE WATERS 14 FT. HEAVY 
FREEZING SPRAY. 
.TONIGHT...N WIND 25 KT. SEAS IN ICE FREE WATERS 9 FT. HEAVY 
FREEZING SPRAY. 
.WED...W WIND 25 KT. SEAS IN ICE FREE WATERS 8 FT. FREEZING SPRAY. 
.WED NIGHT...NW WIND 20 KT. SEAS IN ICE FREE WATERS 7 FT. 
.THU...W WIND 15 KT. SEAS IN ICE FREE WATERS 6 FT. 
.FRI...S WIND 20 KT. SEAS IN ICE FREE WATERS 6 FT. 
.SAT...SW WIND 15 KT. SEAS IN ICE FREE WATERS 6 FT.  

$$

PKZ413-150200-
BERING SEA OFFSHORE 171W TO 180 AND SOUTH OF 56N
400 AM AKDT TUE APR 14 2009

...GALE WARNING TODAY...

.TODAY...NE WIND 45 KT DIMINISHING TO N 35 KT IN THE AFTERNOON. 
SEAS 22 FT. FREEZING SPRAY. 
.TONIGHT...N WIND 30 KT. SEAS 15 FT. FREEZING SPRAY. 
.WED...W WIND 20 KT. SEAS 10 FT. 
.WED NIGHT...NW WIND 25 KT. SEAS 9 FT. 
.THU...W WIND 20 KT. SEAS 8 FT. 
.FRI AND SAT...S WIND 20 KT. SEAS 6 FT.  

$$

PKZ414-150200-
BERING SEA OFFSHORE EAST OF 171W
400 AM AKDT TUE APR 14 2009

...GALE WARNING THROUGH TONIGHT...
...HEAVY FREEZING SPRAY WARNING THROUGH WEDNESDAY...

.TODAY...N WIND 40 KT. SEAS IN ICE FREE WATERS 15 FT. HEAVY FREEZING
SPRAY. 
.TONIGHT...N WIND 35 KT. SEAS IN ICE FREE WATERS 12 FT. SNOW 
SHOWERS. HEAVY FREEZING SPRAY. 
.WED...NW WIND 25 KT. SEAS IN ICE FREE WATERS 8 FT. HEAVY FREEZING
SPRAY. 
.WED NIGHT...NW WIND 25 KT. SEAS IN ICE FREE WATERS 7 FT. 
.THU...N WIND 20 KT. SEAS IN ICE FREE WATERS 6 FT. 
.FRI...NW WIND 20 KT. SEAS IN ICE FREE WATERS 5 FT. 
.SAT...NW WIND 15 KT. SEAS IN ICE FREE WATERS 3 FT.  

$$

AREA FORECAST DISCUSSION
SOUTHCENTRAL AND SOUTHWEST ALASKA
400 AM AKDT MON APR 13 2009

.ANALYSIS AND UPPER LEVELS...
THE LOW IN THE NORTHERN GULF HAS DISSIPATED THIS MORNING...ALTHOUGH
SCATTERED SHOWERS ARE STILL IMPACTING COASTAL PORTIONS OF
SOUTHCENTRAL. WEAK SURFACE RIDGING BUILDING BEHIND THIS LOW IS
CURRENTLY OVER SOUTHWEST ALASKA AND KODIAK ISLAND. A LARGE 996 MB LOW
IS LOCATED JUST NORTH OF ATKA. THIS LOW IS EXPECTED TO MOVE EAST INTO
THE GULF OF ALASKA ON TUESDAY...AND WILL BE THE MAIN WEATHER FOCUS
OVER THE NEXT SEVERAL DAYS.

IN THE UPPER LEVELS...A ROBUST CLOSED LOW IS LOCATED OVER THE
KUSKOKWIM DELTA...WITH A BROAD LONGWAVE TROUGH OVER MAINLAND ALASKA.
RIDGING IS LOCATED OVER THE BERING SEA AND EASTERN ALEUTIANS...BUT IS
BEING UNDERCUT BY ANOTHER UPPER LOW ASSOCIATED WITH THE SURFACE LOW
NEAR ATKA.

.MODEL DISCUSSION...
MODELS ARE CONTINUING TO HAVE DIFFICULTY RESOLVING THE EVOLUTION OF
THE LOW CURRENTLY NORTH OF ATKA AFTER TUESDAY. ALL SOLUTIONS DO AGREE
ON A COMPLEX LOW CENTER BECOMING NEARLY STATIONARY IN THE GULF BY
TUESDAY NIGHT...BUT THE POSITIONING OF THE INDIVIDUAL CENTERS IS THE
MAIN POINT OF CONTENTION. A NAM AND GFS BLEND WAS USED ONCE AGAIN FOR
CONSTRUCTING THE MORNING FORECAST PACKAGE THROUGH THE SHORT
TERM...WITH ONLY RELATIVELY MINOR CHANGES.

.SHORT TERM FORECAST...
.SOUTHCENTRAL...SNOW HAS BROKEN OUT ACROSS PORTIONS OF SOUTHCENTRAL
THIS MORNING...AS THE UPPER LOW OVER SOUTHWEST AK AND AN ASSOCIATED
TROUGH SWING ACROSS THE AREA. GOOD ISENTROPIC LIFT IS EXPECTED TO
CONTINUE ACROSS THE ANCHORAGE BOWL AND VICINITY THROUGH THIS
AFTERNOON. AS A RESULT...SNOW SHOWERS WILL PERSIST TODAY AS THE UPPER
LOW PASSES TO THE NORTHWEST. ONSHORE FLOW WILL ALSO BE INCREASING
THROUGHOUT THE DAY...AS A FRONT ASSOCIATED WITH THE LOW NEAR ATKA
MOVES INTO SOUTHCENTRAL. ANTICIPATE SNOW AND RAIN TO OVERSPREAD
KODIAK THIS AFTERNOON...MOVING INTO THE REST OF THE AREA BY TONIGHT.
EXPECT HEAVIEST PRECIPITATION ASSOCIATED WITH THIS FRONT TO FALL
ALONG THE COAST...WITH UPSLOPE SNOW ALONG THE SUSITNA VALLEY...AND
LIGHTER SNOW ELSEWHERE. RAIN AND SNOW SHOWERS UNDER SOUTHERLY FLOW
WILL CONTINUE THROUGH TUESDAY AS THE LOW BECOMES NEARLY STATIONARY
SOUTH OF KODIAK ISLAND.

.SOUTHWEST...THE DEEP UPPER LOW WILL CONTINUE TO RESULT IN SNOW
ACROSS PORTIONS OF THE KUSKOKWIM VALLEY TODAY DUE TO STRONG DYNAMICS.
AS THE UPPER LOW MOVES INTO INTERIOR ALASKA...EXPECT SHOWERS TO
GRADUALLY DIMINISH THIS EVENING. THE LOW OVER THE ALEUTIANS WILL BE
SPREADING MOISTURE BACK OVER THE AKPEN AND BRISTOL BAY TODAY INTO
TONIGHT. WARM AIR ASSOCIATED WITH THIS SYSTEM WILL EVENTUALLY BRING A
RAIN AND SNOW MIX TO THESE AREAS. THE KUSKOKWIM DELTA IS EXPECTED TO
REMAIN DRY WITH THIS SYSTEM...ALTHOUGH SNOW SHOWERS WILL BE ON THE
INCREASE ALONG THE KUSKOKWIM VALLEY DUE TO FAVORABLE UPSLOPE FLOW.

.BERING SEA AND ALEUTIANS...THE LOW NEAR ATKA WILL MOVE EASTWARD INTO
THE WESTERN GULF OF ALASKA BY TUESDAY. RAIN AND SNOW ASSOCIATED WITH
THIS LOW WILL BE MOST WIDESPREAD ACROSS THE EASTERN ALEUTIANS TODAY.
COLD ADVECTION AND NORTHERLY FLOW ON THE BACK SIDE OF THE LOW WILL
CHANGE SCATTERED SHOWERS BACK OVER TO SNOW. HIGH PRESSURE WILL BE
BUILDING OVER THE WESTERN AND CENTRAL ALEUTIANS TUESDAY...HELPING TO
CLEAR OUT ANY REMAINING PRECIPITATION.

.LONG TERM FORECAST...
AS PREVIOUSLY MENTIONED...THE LOW PRESSURE CENTER IS EXPECTED TO PARK
ITSELF OVER THE CENTRAL AND SOUTHERN GULF OF ALASKA THROUGH THE END
OF THE WEEK. THIS WILL KEEP PRECIPITATION CHANCES CONFINED MAINLY TO
COASTAL LOCATIONS. HIGH PRESSURE WILL BUILD OVER THE BERING SEA AND
ALEUTIANS WITH GENERALLY FAIR WEATHER AS WE HEAD THROUGH THE END OF
THE WEEK.

.AER/ALU...WATCH/WARNING SUMMARY
PUBLIC...NONE
MARINE...GALE...132 165 170 172 179
         HEAVY FREEZING SPRAY...179
FIRE WEATHER...NONE

NRH APR 09