Storm Warning 190, NWS Anchorage, AK

516 
FZAK62 PAFC 250016
OFFALU

OFFSHORE WATERS FORECAST
NATIONAL WEATHER SERVICE ANCHORAGE AK
400 PM AKST TUE DEC 24 2013

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.

PKZ499-251500-
400 PM AKST TUE DEC 24 2013
.SYNOPSIS FOR CENTRAL BERING SEA...
A 974 MB LOW NEAR 50N 179W WILL MOVE TO NEAR 52N 174W AT 987 MB WED
MORNING AND THEN DISSIPATE. AN ASSOCIATED WEATHER FRONT WILL STALL
OVER THE CENTRAL BERING SEA. A 968 MB LOW NEAR 45N 179E WED EVENING
WILL MOVE TO 48N 177W AT 961 MB THU AFTERNOON.
$$

PKZ411-251500-
BERING SEA OFFSHORE WEST OF 180 AND EAST OF THE INTERNATIONAL
DATELINE
400 PM AKST TUE DEC 24 2013

.TONIGHT...E WIND 15 TO 30 KT. STRONGEST N OF 56N. SEAS 12 TO 19 FT.
PATCHY FOG. RAIN.
.WED...S TO E WIND 15 TO 30 KT. STRONGEST N OF 56N. SEAS 10 TO 14 FT.
PATCHY FOG. RAIN.
.WED NIGHT...E WIND 15 TO 30 KT. STRONGEST N OF 56N. SEAS 9 TO 13 FT.

.THU...NE WIND 30 KT. SEAS 12 FT. 
.THU NIGHT...NE WIND 35 KT. SEAS 12 FT. 
.FRI...NE WIND 30 KT. SEAS 13 FT. 
.SAT...E WIND 30 KT. SEAS 15 FT. 
.SUN...E WIND 30 KT. SEAS 19 FT.  

$$

PKZ412-251500-
BERING SEA OFFSHORE 171W TO 180 AND NORTH OF 56N
400 PM AKST TUE DEC 24 2013

...GALE WARNING THROUGH WEDNESDAY NIGHT...

.TONIGHT...E WIND 25 TO 35 KT. SEAS 13 TO 19 FT. PATCHY FOG. RAIN AND
SNOW. 
.WED...E WIND 25 TO 35 KT. SEAS 12 TO 15 FT. RAIN AND SNOW. 
.WED NIGHT...E WIND 25 TO 35 KT. SEAS 10 TO 14 FT. 
.THU...E WIND 30 KT. SEAS 11 FT. 
.THU NIGHT...NE WIND 35 KT. SEAS 12 FT. 
.FRI...NE WIND 35 KT. SEAS 13 FT. 
.SAT AND SUN...E WIND 25 KT. SEAS 10 TO 12 FT. 

$$

PKZ413-251500-
BERING SEA OFFSHORE 171W TO 180 AND SOUTH OF 56N
400 PM AKST TUE DEC 24 2013

.TONIGHT...E WIND 15 TO 25 KT. SEAS 13 FT. PATCHY FOG. RAIN.
.WED...E WIND 15 TO 25 KT BECOMING VARIABLE 15 KT IN THE AFTERNOON.
SEAS 10 FT. PATCHY FOG. 
.WED NIGHT...E WIND 10 TO 15 KT. SEAS 9 FT. 
.THU...E WIND 30 KT. SEAS 9 FT. 
.THU NIGHT...NE WIND 35 KT. SEAS 12 FT. 
.FRI...NE WIND 35 KT. SEAS 15 FT. 
.SAT AND SUN...E WIND 25 KT. SEAS 11 FT.  

$$

PKZ414-251500-
BERING SEA OFFSHORE EAST OF 171W
400 PM AKST TUE DEC 24 2013

.TONIGHT...E WIND 30 KT. SEAS 8 TO 11 FT. RAIN.
.WED...E WIND 20 TO 30 KT. SEAS 10 FT. 
.WED NIGHT...E WIND 15 TO 25 KT. SEAS 8 FT. 
.THU...E WIND 25 KT. SEAS 7 FT. 
.THU NIGHT...E WIND 35 KT. SEAS 10 FT. 
.FRI...NE WIND 35 KT. SEAS 13 FT. 
.SAT...E WIND 20 KT. SEAS 9 FT. 
.SUN...SE WIND 25 KT. SEAS 7 FT.  

$$

SOUTHCENTRAL AND SOUTHWEST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE ANCHORAGE AK
400 PM AKST MON DEC 23 2013

.ANALYSIS AND UPPER LEVELS...THE UPPER LEVEL PATTERN ON TODAY'S
WEATHER MAP SHOWS A LOW IN THE ARCTIC WITH TROUGH EXTENDED SOUTHWARD
OVER THE ALCAN BORDER WITH ANOTHER LOW CENTERED JUST SOUTH OF ATTU.
IN BETWEEN THERE IS A FAIRLY HIGH AMPLITUDE RIDGE OVER THE WESTERN
GULF THROUGH SOUTHWEST ALASKA WHICH IS BUILDING EASTWARD. WHILE THE
MAIN JET STREAM LIES WELL SOUTH OF THE FORECAST AREA THERE SI A JET
STREAK OVER THE NORTH GULF COAST WHICH HELPED TO INCREASE WINDS IN
THE AREA TODAY. THIS FEATURE IS ALSO MOVING EASTWARD AND OUT OF THE
AREA.
AT THE SURFACE THERE IS HIGH PRESSURE OVER THE WESTERN AND INTERIOR
OF THE STATE AS A LOW IN THE NORTHEAST GULF MOVES EASTWARD. A STRONG
965 MB LOW IS SOUTH OF ATTU WITH A FRONT THAT STRETCHES INTO THE
BERING SEA AND THEN BACK OVER THE EASTERN ALEUTIANS.

.MODEL DISCUSSION...MODELS ARE HAVING SOME DIFFICULTIES WITH THE
WEATHER PATTERN ALONG THE ALEUTIANS THROUGH THE GULF OF ALASKA. THE
MAINLAND PART OF THE STATE IS COMING UNDER HIGH PRESSURE WHICH THE
MODELS DO AGREE UPON BUT THE SOUTHERN PART OF THE REGIONS A DIFFERENT
STORY. THE FIRST ITEM WHERE THE MODELS HAVE A DISCREPANCY IS WITH A
LOW DEVELOPING SOUTHWEST OF THE GULF OF ALASKA TONIGHT WHICH WILL
MOVE INTO THE GULF TOMORROW. THE 12Z NAM WAS THE MODELS PREFERRED DUE
TO ITS TRACK AND STRENGTH. THIS WILL IMPACT HOW MUCH
PRECIPITATION...IF ANY...WILL BE ABLE TO MAKE IT TO THE NORTH GULF
COAST. THIS WILL ALSO IMPACT KODIAK AS THE NAM SOLUTION KEEPS
PRECIPITATION TYPE SNOW FOR THE ENTIRE ISLAND WHERE THE GFS SOLUTION
WOULD CHANGE THE SOUTHERN PART OF THE ISLAND TO RAIN.
THESE DIFFERENCE ARE SMALL COMPARED TO THE MESS THAT COMPRISES THE
MODELS SOLUTIONS IN THE ALEUTIANS FROM WEDNESDAY ONWARD. WHAT CAN BE
ASCERTAINED IS THAT THERE WILL LIKELY BE THREE SEPARATE LOW CENTERS.
FIVE DIFFERENT MODELS HAVE FIVE DIFFERENT SOLUTIONS AS TO WHERE THEY
WILL ALL BE BY THURSDAY. AN EXAMPLE OF THE DIFFICULTY THESE MODELS
ARE HAVING IS FOUND IN THAT THE GFS ENSEMBLE MEAN SOLUTION IS CLOSER
TO THE ECMWF SOLUTION THAT IT IS TO THE GFS'S OWN OPERATIONAL
SOLUTION. THEREFORE THERE IS LOW CONFIDENCE IN THE DETAILS OF THE
FORECASTS FOR THE ALEUTIANS AND SOUTHERN BERING SEA IN THE WEDNESDAY
THROUGH FRIDAY TIME PERIOD.

.SHORT TERM FORECAST...
SOUTH CENTRAL...SKIES WILL CONTINUE TO CLEAR OVERNIGHT FOR MOST OF
THE AREA. THE DECREASING PRESSURE GRADIENT WILL ALSO DIMINISH WINDS
BRINGING IN MUCH COLDER TEMPERATURES BEGINNING TONIGHT THAN HAS BEEN
SEEN FOR THE PAST FEW DAYS. THE EXCEPTION WILL BE KODIAK ISLAND WHICH
WILL SEE CLOUDS INCREASE OVERNIGHT WITH SNOW BEGINNING TUESDAY
MORNING AND PERSISTING THROUGH THE DAY AND INTO THE OVERNIGHT PERIOD
FOR TUESDAY NIGHT. THE NORTH GULF COAST WILL SEE INCREASED CLOUD
COVER TOMORROW AS THE LOW MOVES THROUGH THE GULF. AT THIS TIME IT
LOOKS LIKE THERE WILL NOT BE MUCH IN THE WAY OF SNOW FOR THE GULF
COAST...WITH THE MOST LIKELY PLACE TO SEE ANY BEING THE CORDOVA AREA.

SOUTHWEST...CLOUDS WILL INCREASE SOME OVERNIGHT DUE TO THE FRONT
PUSHING NORTHWARD THROUGH THE BERING SEA. THE HIGH PRESSURE OVER THE
MAINLAND PART OF THE STATE SHOULD BE SUFFICIENT TO KEEP ANY SNOW
RELEGATED TO ALONG THE BRISTOL BAY COAST. AS SOON AS THIS WAVE MOVES
THROUGH THERE SHOULD BE SOME CLEARING AGAIN UNDER THE HIGH PRESSURE.

ALEUTIANS AND BERING SEA...THE BIGGEST CHALLENGE WITH THIS REGION IS
THE PROBLEMS WITH THE COMPUTER MODEL SOLUTIONS FOR THIS REGION.
HOWEVER IT DOES LOOK LIKELY THAT PREDOMINATE SOUTHEAST FLOW WILL BE
OVER MOST OF THIS AREA BRINGING IN MOSTLY RAIN TO THE AREA WITH JUST
A LITTLE BIT OF SNOWFALL IN A FEW AREAS.

.LONG TERM FORECAST...
SOUTH CENTRAL AND SOUTHWEST MAINLAND ALASKA SHOULD REMAIN MOSTLY DRY
UNDER THE HIGH PRESSURE FOR THE SECOND HALF OF THE WEEK.
THERE IS A LOT OF UNCERTAINTY IN THE ALEUTIANS DUE TO THE MODEL
UNCERTAINTY. HOWEVER THE STORM TRACK WILL BE IN THIS REGION SO
PERIODS OF STRONG WINDS AND PRECIPITATION SHOULD BE EXPECTED.

.AER/ALU...WATCH/WARNING SUMMARY
PUBLIC...NONE.
MARINE...GALE 119 120 131 132 155 165 170 172 179 180 181 185.
         HEAVY FREEZING SPRAY 130 139 181 185.
FIRE WEATHER...NONE.

DEC 13