Gale Warning 428, NWS Anchorage, AK

925 
FZAK62 PAFC 212315
OFFALU

OFFSHORE WATERS FORECAST
NATIONAL WEATHER SERVICE ANCHORAGE AK
400 PM AKDT THU JUN 21 2012

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.

PKZ499-221500-
400 PM AKDT THU JUN 21 2012
.SYNOPSIS FOR CENTRAL BERING SEA...
A 997 MB LOW NEAR 50N 178W WILL WEAKEN TO 1001 MB NEAR 59N 177W 
SAT AFTERNOON.
$$

PKZ411-221500-
BERING SEA OFFSHORE WEST OF 180 AND EAST OF THE INTERNATIONAL
DATELINE
400 PM AKDT THU JUN 21 2012

.TONIGHT...NE WIND 10 TO 20 KT. SEAS 5 FT. PATCHY FOG. 
.FRI...NE WIND 10 TO 20 KT. SEAS 6 FT. PATCHY FOG. 
.FRI NIGHT...N WIND 10 TO 20 KT. SEAS 6 FT. PATCHY FOG. 
.SAT...W WIND 20 KT. SEAS 6 FT. 
.SAT NIGHT THROUGH SUN...NW WIND 25 KT. SEAS 6 FT. 
.MON...W WIND 15 KT. SEAS 5 FT. 
.TUE...W WIND 20 KT. SEAS 5 FT.  

$$

PKZ412-221500-
BERING SEA OFFSHORE 171W TO 180 AND NORTH OF 56N
400 PM AKDT THU JUN 21 2012

.TONIGHT...E WIND 15 TO 25 KT. SEAS 6 FT. PATCHY FOG. 
.FRI...E WIND 15 TO 25 KT. SEAS 7 FT. PATCHY FOG. 
.FRI NIGHT...NE WIND 20 KT DIMINISHING TO VARIABLE 10 KT AFTER
MIDNIGHT. SEAS 7 FT. PATCHY FOG. RAIN.
.SAT...VARIABLE WIND 10 KT BECOMING W 15 KT IN THE AFTERNOON. 
SEAS 6 FT. 
.SAT NIGHT...W WIND 15 KT. SEAS 6 FT. 
.SUN...NW WIND 20 KT. SEAS 5 FT. 
.MON...W WIND 20 KT. SEAS 5 FT. 
.TUE...W WIND 15 KT. SEAS 5 FT.  

$$

PKZ413-221500-
BERING SEA OFFSHORE 171W TO 180 AND SOUTH OF 56N
400 PM AKDT THU JUN 21 2012

...GALE WARNING TONIGHT...

.TONIGHT...E WIND 25 TO 35 KT. SEAS 9 FT. PATCHY FOG. RAIN.
.FRI...NE WIND 25 KT. SEAS 9 FT. RAIN.
.FRI NIGHT...NE WIND 20 KT BECOMING NW AFTER MIDNIGHT. SEAS 7 FT.
RAIN.
.SAT...W WIND 20 KT. SEAS 6 FT. 
.SAT NIGHT THROUGH SUN...W WIND 25 KT. SEAS 6 FT. 
.MON...W WIND 20 KT. SEAS 6 FT. 
.TUE...W WIND 15 KT. SEAS 5 FT.  

$$

PKZ414-221500-
BERING SEA OFFSHORE EAST OF 171W
400 PM AKDT THU JUN 21 2012

.TONIGHT...E WIND 20 TO 30 KT. SEAS 7 FT. PATCHY FOG. 
.FRI...E WIND 15 T0 25 KT. SEAS 7 FT. PATCHY FOG. 
.FRI NIGHT...E WIND 20 KT BECOMING S 20 KT AFTER MIDNIGHT.
SEAS 6 FT. 
.SAT...S WIND 20 KT. SEAS 6 FT. 
.SAT NIGHT THROUGH MON...SW WIND 20 KT. SEAS 6 FT. 
.TUE...W WIND 15 KT. SEAS 5 FT.  

$$

150 
FZAK62 PAFC 221100
OFFALU

OFFSHORE WATERS FORECAST
NATIONAL WEATHER SERVICE ANCHORAGE AK
400 AM AKDT FRI JUN 22 2012

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.

PKZ499-230300-
400 AM AKDT FRI JUN 22 2012
.SYNOPSIS FOR CENTRAL BERING SEA...
A 999 MB LOW NEAR 50N 179W WEAKENS TO 1003 MB NEAR 57N 174W SAT
MORNING. THIS LOW WILL MERGE WITH A LOW COMING OFF THE KAMCHATKA
PENINSULA TO FORM A COMPLEX LOW IN THE NORTHERN BERING SEA BY SAT
NIGHT.

$$

PKZ411-230300-
BERING SEA OFFSHORE WEST OF 180 AND EAST OF THE INTERNATIONAL
DATELINE
400 AM AKDT FRI JUN 22 2012

.TODAY...NE WIND 25 KT. SEAS 7 FT. PATCHY FOG. 
.TONIGHT...N WIND 20 KT. SEAS 7 FT. PATCHY FOG. 
.SAT AND SAT NIGHT...W WIND 20 KT. SEAS 6 FT. 
.SUN...NW WIND 20 KT. SEAS 6 FT. 
.MON AND TUE...W WIND 15 KT. SEAS 5 FT.  

$$

PKZ412-230300-
BERING SEA OFFSHORE 171W TO 180 AND NORTH OF 56N
400 AM AKDT FRI JUN 22 2012

.TODAY...NE WIND 25 KT. SEAS 7 FT. PATCHY FOG. 
.TONIGHT...NE WIND 20 KT. SEAS 6 FT. PATCHY FOG. RAIN.
.SAT...NE WIND 15 KT IN THE MORNING BECOMING VARIABLE 10 KT. SEAS 5
FT. 
.SAT NIGHT...SW WIND 15 KT. SEAS 4 FT. 
.SUN...W WIND 15 KT. SEAS 4 FT. 
.MON...NW WIND 20 KT. SEAS 5 FT. 
.TUE...W WIND 15 KT. SEAS 4 FT.  

$$

PKZ413-230300-
BERING SEA OFFSHORE 171W TO 180 AND SOUTH OF 56N
400 AM AKDT FRI JUN 22 2012

.TODAY...NE WIND 30 KT. SEAS 9 FT. RAIN.
.TONIGHT...E WIND 20 KT BECOMING W AFTER MIDNIGHT. SEAS 7 FT. RAIN.
.SAT...W WIND 15 KT. SEAS 6 FT. 
.SAT NIGHT AND SUN...W WIND 25 KT. SEAS 6 FT. 
.MON...W WIND 20 KT. SEAS 5 FT. 
.TUE...W WIND 15 KT. SEAS 4 FT.  

$$

PKZ414-230300-
BERING SEA OFFSHORE EAST OF 171W
400 AM AKDT FRI JUN 22 2012

.TODAY...E WIND 25 KT. SEAS 7 FT. PATCHY FOG. 
.TONIGHT...SE WIND 20 KT. SEAS 6 FT. 
.SAT...S WIND 20 KT. SEAS 6 FT. 
.SAT NIGHT...SW WIND 20 KT. SEAS 6 FT. 
.SUN...SW WIND 25 KT. SEAS 5 FT. 
.MON AND TUE...W WIND 15 KT. SEAS 4 FT.  

$$

SOUTHCENTRAL AND SOUTHWEST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE ANCHORAGE AK
500 PM AKDT WED JUN 20 2012

.MODEL DISCUSSION...

LOW CONFIDENCE IN NUMERICAL MODELS IN THE MID AND LONG RANGE.
CONCENTRATED GRID EDITS ON FIRST 60 HOURS THEN TRENDED INTO INHERITED
PACKAGE.

MODELS ARE IN GOOD AGREEMENT THROUGH THE SHORT TERM...DISCREPANCIES
ONLY BECOME NOTICEABLE BEYOND 48 HOURS. NAM WAS THE OUTLIER AMONG 12Z
RUNS...MOVES IN NEXT BERING LOW TOO QUICKLY. GFS PREFERRED OUT WEST
THOUGH IT LACKS DETAIL...WILL NEED TO FURTHER REFINE FORECAST IN
FUTURE PACKAGES. BOTH GFS AND EC ARE CONSOLIDATING ALL THE ENERGY OF
THE WESTERN STORM SYSTEM INTO A SINGLE STACKED LOW INSTEAD OF
DISTRIBUTING IT AMONG MULTIPLE SMALLER FEATURES. NAM NEVERTHELESS WAS
PREFERRED IN THE EASTERN DOMAIN WHERE IT CAPTURED AN INVERTED TROUGH
ALONG THE NORTH GULF COAST THURSDAY NIGHT WHICH THE OTHER MODELS ONLY
HINTED AT. OVERALL...NAM HAS BEST HANDLE ON DIURNAL FLUCTUATION IN
SURFACE PRESSURE GRADIENT EAST OF 160W BUT UMKET GOOD ALSO.

.UPPER LEVELS AND EXTENDED OUTLOOK...

CUT OFF UPPER LEVEL LOW OVER GULF OF ALASKA GRADUALLY SLIDES
SOUTHEASTWARD...INTO BRITISH COLUMBIA BY FRIDAY AFTERNOON. LONG WAVE
TROUGH OVER BERING SEA AND CENTRAL ALEUTIANS STRENGTHENS THROUGH THE
WEEKEND. RIDGE OF HIGH PRESSURE ALOFT OVER THE EASTERN BERING MOVES
OVER THE SOUTHWEST MAINLAND BY THURSDAY AFTERNOON AND RECEDES INTO
THE NORTH PACIFIC BY FRIDAY NIGHT.

.SURFACE FEATURES...

A BROAD AREA OF WEAK HIGH PRESSURE WILL PERSIST ACROSS THE GULF OF
ALASKA THROUGH FRI AFTERNOON. A TROUGH OF LOW PRESSURE DEVELOPS ALONG
THE NORTH GULF COAST THU NIGHT. A RIDGE OF HIGH PRESSURE HOLDS OVER
THE CENTRAL CENTRAL BERING SEA THROUGH THU AFTERNOON THEN WEAKENS AS
IT MOVES INLAND ON FRIDAY. A 999 MB NORTHWEST PACIFIC LOW WILL MOVE
TO NEAR ADAK FRI AFTERNOON WITH LITTLE CHANGE IN CENTRAL PRESSURE.

.ANALYSIS AND NEAR TERM FORECAST...

AIRMASS OVER SOUTHCENTRAL ALASKA IS MOIST IN THE LOWER LEVELS AND
UNSTABLE IN THE UPPER LEVELS. MARINE LAYER THICKENED OVERNIGHT ACROSS
MOST OF COASTAL SOUTHCENTRAL...INCLUDING COOK INLET...AND DIDNT BURN
OFF UNTIL NEARLY NOON. CONDITIONS LIKELY TO REDEVELOP EARLY THURSDAY
MORNING AND AGAIN TO A LESSER DEGREE ON FRIDAY. WEAK INVERSION ALOFT
HELPED TO TRAP THE MARINE LAYER THIS MORNING AND TO CAP MUCH OF THIS
AFTERNOONS CONVECTION. LITTLE POTENTIAL FOR THUNDERSTORMS TODAY OR
TOMORROW OUTSIDE THE CONTINENTALLY INFLUENCED SUSITNA VALLEY AND
COPPER RIVER BASIN...THOUGH HIGHER ELEVATIONS OF THE CHUGACH RANGE
AND KENAI MOUNTAINS MAY YET EXPERIENCE A FEW STRIKES. MID AND HIGH
LEVEL CLOUDS ASSOCIATED WITH THE UPPER LEVEL GULF LOW ARE ALSO
HELPING TO DAMPEN CONVECTIVE ACTIVITY BY LIMITING THE AMOUNT OF
DAYTIME HEATING.

WESTERLY FLOW OUT WEST HAS PUSHED THE BERING SEA MARINE LAYER WELL
INLAND. FOG BEGAN TO LIFT TOWARDS NOON BUT A MODERATE TO THICK
STRATUS DECK WILL KEEP MOST COASTAL AREAS OF SOUTHWEST ALASKA FROM
BREAKING 60 DEGREES. MEKORYUK...LOCATED NOT FAR FROM THE LINGERING
ICE EDGE...DIDNT BREAK 40 DEGREES UNTIL AFTER NOON. NEAR ZERO
VISIBILITIES LIKELY TO REDEVELOP ACROSS THE EASTERN BERING AND BERING
SEA COASTLINE AGAIN TONIGHT. CONDITIONS IMPROVING FRIDAY NIGHT WHEN
THE LOW LEVEL WINDS ARE PROGGED TO SHIFT TO THE EAST
SOUTHEAST...AHEAD OF THE APPROACHING BERING SEA LOW.

STILL SOME UNCERTAINTY REGARDING TIMING OF THIS NEXT BERING LOW...BUT
MODELS DO AGREE ON CARRYING THE ASSOCIATED WARM FRONT INTO THE
CENTRAL ALEUTIANS TOMORROW MORNING AND THEN INTO THE SOUTHERN BERING
AND EASTERN ALEUTIANS THURSDAY NIGHT...GRADUALLY OCCLUDING ALONG THE
WAY. FRONT SHOULD WEAKEN JUST AS IT REACHES THE PRIBILOFS AND ALASKA
PENINSULA FRIDAY MORNING. PLENTY OF STEADY RAIN ALONG AND IN ADVANCE
OF THE FRONT. AREAS OF FOG AND PATCHY LIGHT RAIN WILL PERSIST ACROSS
THE WESTERN ALEUTIANS AND THE REMAINDER OF THE BERING.

.EXTENDED FORECAST...

BREAK DOWN OF UPPER LEVEL RIDGE FRIDAY NIGHT WILL USHER IN A SHIFT IN
THE STORM TRACK...ALLOWING ALEUTIAN AND BERING LOWS TO MOVE DIRECTLY
INTO THE SOUTHERN MAINLAND OF THE STATE. COMING WEEK PROMISES TO BE
COOL AND DAMP FOR THE MAINLAND...WITH A FEW GUSTY WINDS OUT OVER THE
BERING.

.AER/ALU...WATCH/WARNING SUMMARY
PUBLIC...NONE
MARINE...GALE 172
FIRE WEATHER...NONE

ASB JUN 12