Gale Warning 925, NWS Anchorage, AK

758 
FZAK61 PAFC 111254
OFFAER

OFFSHORE WATERS FORECAST
NATIONAL WEATHER SERVICE ANCHORAGE AK
400 AM AKST SUN DEC 11 2011

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.

PKZ399-120300-
400 AM AKST SUN DEC 11 2011
.SYNOPSIS FOR THE WESTERN GULF OF ALASKA...A STRONG FRONT WILL BECOME
STATIONARY OVER THE CENTRAL GULF TODAY. A 981 MB LOW OVER THE CENTRAL
NORTH PACIFIC WILL STRENGTHEN TO 967 MB NEAR 57N 151W THIS AFTERNOON
THEN WILL WEAKEN TO 973 MB NEAR 60N 147W LATE TONIGHT THEN MOVE
INLAND MON MORNING. 

$$

PKZ351-120300-
GULF OF ALASKA OFFSHORE NORTH OF 57N AND WEST OF 144W
400 AM AKST SUN DEC 11 2011

...STORM WARNING THROUGH MONDAY...

.TODAY...SE WIND 40 KT INCREASING TO 50 KT IN THE AFTERNOON. SEAS
BUILDING 15 TO 20 FT. RAIN.
.TONIGHT...SW WIND 55 KT. SEAS 26 FT. 
.MON...W WIND 50 KT DIMINISHING TO 40 KT IN THE AFTERNOON. SEAS
26 FT. 
.MON NIGHT...W WIND 30 KT. SEAS 20 FT. 
.TUE...S WIND 20 KT. SEAS 12 FT. 
.WED...SE WIND 25 KT. SEAS 13 FT. 
.THU...SE WIND 30 KT. SEAS 17 FT.  

$$

PKZ352-120300-
GULF OF ALASKA OFFSHORE SOUTH OF 57N NORTH OF 55N AND WEST OF
144W
400 AM AKST SUN DEC 11 2011

...STORM WARNING TONIGHT...

.TODAY...S WIND 45 KT. SEAS 15 TO 20 FT. RAIN.
.TONIGHT...SW WIND 55 KT. SEAS 26 FT. 
.MON...W WIND 40 KT DIMINISHING TO 30 KT IN THE AFTERNOON. SEAS
24 FT. 
.MON NIGHT...W WIND 25 KT. SEAS 19 FT. 
.TUE...S WIND 30 KT. SEAS 13 FT. 
.WED...SE WIND 30 KT. SEAS 15 FT. 
.THU...SE WIND 25 KT. SEAS 18 FT.  

$$

SOUTHCENTRAL AND SOUTHWEST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE ANCHORAGE AK
530 AM AKST SAT DEC 10 2011

.ANALYSIS AND UPPER LEVELS...
AN IMPRESSIVE 955 MB LOW CENTERED EAST OF THE KAMCHATKA PENINSULA
ENCOMPASSES MUCH OF THE BERING SEA. ITS ASSOCIATED FRONT SUPPORTED
GUSTS OVER 60 MPH AT DUTCH HARBOR LAST NIGHT AND IS CURRENTLY CAUSING
GUSTY WINDS ACROSS THE AKPEN. THE FRONT IS RAPIDLY OCCLUDING JUST
OFFSHORE OF THE KUSKOKWIM DELTA...AND PRECIPITATION IS BEGINNING TO
MOVE INLAND ALONG THE COAST. MEANWHILE...A SURFACE HIGH CENTERED OVER
SOUTHCENTRAL ALASKA IS HELPING TO GENERATE FOG ACROSS COOK INLET THIS
MORNING.

UPPER LEVEL DYNAMICS CONTINUE TO SUPPORT THIS STRONG LOW PRESSURE
SYSTEM. A 130 KT JET IS STREAMING MOISTURE NORTHWARD FROM THE PACIFIC
OCEAN. BOTH THIS JET AND COPIOUS AMOUNT OF MOISTURE WILL PLAY A
PIVOTAL ROLE IN MAINTAINING THE STRENGTH OF THE SURFACE LOW PRESSURE
SYSTEM THROUGH THIS EVENING...DESPITE THE FACT THOUGH IT HAS ALREADY
OCCLUDED.

.MODEL DISCUSSION...
MODELS CONTINUE TO SHOW LARGE DISCREPANCIES...EVEN IN THE NEXT 24 TO
48 HOURS. OUT WEST...THE NAM OCCLUDES THE LOW PRESSURE SYSTEM FARTHER
SOUTH THAN THE GFS DOES...WHICH ALLOWS COOLER AIR TO FILTER INTO THE
KUSKOKWIM DELTA AND NORTH BRISTOL BAY REGIONS. THIS SCENARIO WOULD
RESULT IN GREATER SNOW ACCUMULATION IN THE NORTHERN BRISTOL BAY ZONE
REGION AND BLIZZARD CONDITIONS ACROSS THE KUSKOKWIM DELTA COAST.
DISCREPANCIES EXIST FOR THE SOUTHCENTRAL ZONE AS WELL. THE NAM AND
GFS DEVELOP A TRIPLE POINT LOW DIFFERENTLY NEAR THE KENAI PENINSULA
TONIGHT...WHICH WILL DETERMINE WHETHER TURNAGAIN ARM GUSTS REACH THE
ANCHORAGE BOWL.

.SHORT TERM FORECAST...
SOUTH CENTRAL ALASKA...
HIGH PRESSURE IS SUPPORTING FOG ACROSS THE REGION THIS MORNING WITH
THE MOST DENSE FOG LOCATED ALONG THE INLET. THIS FOG SHOULD GRADUALLY
DISSIPATE BY THE MIDDLE OF THE MORNING AS WINDS ALONG THE INLET
INCREASE AND THE FOG BEGINS TO MIX OUT. CLOUDS WILL INCREASE ACROSS
THE REGION TODAY FROM WEST TO EAST AS A POTENT FRONT APPROACHES. SNOW
WILL REACH THE KENAI PENINSULA BY THIS AFTERNOON AND SPREAD
NORTHWARD. WINDS WILL INCREASE THROUGH LOCAL GAPS OVERNIGHT AND ABATE
BY THE MORNING HOURS. TURNAGAIN WINDS MAY POSSIBLY IMPACT PORTIONS OF
THE ANCHORAGE...BUT THERE IS CURRENTLY TOO MUCH OF A DIFFERENCE
BETWEEN MODELS.

.SOUTHWEST ALASKA...THE FRONT ASSOCIATED WITH THE LOW JUST EAST OF
KAMCHATKA WILL CONTINUE TO IMPACT THE SOUTHWEST MAINLAND MUCH OF THE
DAY. NEAR THE TIP OF THE OCCLUSION THIS MORNING...COOLER AIR AND
GUSTY WINDS ARE HELPING TO SUPPORT BLIZZARD CONDITIONS ALONG THE
KUSKOKWIM DELTA COAST. THE WARM SECTOR OF THE OCCLUSION IS EXPECTED
TO REACH THE COAST BY MID MORNING AND IMPROVE VISIBILITY...BUT THERE
IS STILL STRONG MODEL DISAGREEMENT. IN THE WARM SECTOR OF THE
OCCLUSION...GUSTY WINDS AND RAIN ARE OCCURRING ALONG THE ALASKA
PENINSULA. CONDITIONS WILL IMPROVE BY THE AFTERNOON AS THE FRONT
MOVES EASTWARD.

.BERING SEA AND ALEUTIANS...A STRONG FRONT BROUGHT THAT BROUGHT 60
MPH WIND GUSTS TO THE EASTERN ALEUTIANS LAST NIGHT HAS PROGRESSED
EASTWARD. HOWEVER...THE 955 MB LOW WILL STILL SUPPORT SOME GUSTY
WINDS ACROSS THE ALEUTIANS AS IT PROGRESSES SLOWLY NORTHEASTWARD.
LIGHT SHOWERS WILL ALSO OCCUR ACROSS THE ALEUTIAN ISLANDS OVER THE
NEXT FEW DAYS DUE TO THE COLD AIR ADVECTION BEHIND THE LOW. A NEW LOW
PRESSURE SYSTEM WILL APPROACH THE ALEUTIANS BY EARLY MONDAY MORNING.

.LONG TERM FORECAST...
A STRONG JET STREAM WILL CONTINUE TO UNDULATE ACROSS THE NORTH
PACIFIC OVER THE NEXT WEEK. AS A RESULT...STRONG LOW PRESSURE SYSTEMS
WILL CONTINUE TO DEVELOP AND MOVE ACROSS THE BERING.

.AER/ALU...WATCH/WARNING SUMMARY
PUBLIC...DENSE FOG ADVISORY 101...HIGH WIND WARNING 101
         BLIZZARD WARNING 125...BLIZZARD WATCH 131
         BLIZZARD WARNING 155
MARINE...STORM...120 130 132 150 155 160 165 175 176 180
         GALE...125 129 138 140 141 170 171 172 179 185
FIRE WEATHER...NONE

ELN DEC 11