Gale Warning 220, NWS Juneau, AK

350 
FZAK67 PAJK 140044 AAA
OFFAJK

OFFSHORE WATERS FORECAST...UPDATED
NATIONAL WEATHER SERVICE JUNEAU AK
440 PM AKDT SUN MAY 13 2012 

OFFSHORE WATERS FORECAST FOR GULF OF ALASKA EAST OF 144W

WIND FORECASTS REFLECT THE PREDOMINANT SPEED AND DIRECTION
EXPECTED. SEA FORECASTS REPRESENT THE AVERAGE OF THE HIGHEST
ONE-THIRD OF THE COMBINED WINDWAVE AND SWELL HEIGHT.

PKZ398-141400-
400 PM AKDT SUN MAY 13 2012 
.SYNOPSIS FOR THE EASTERN GULF OF ALASKA...
A LOW PRESSURE CENTER IN THE NORTH PACIFIC WILL MOVE INTO THE
CENTRAL GULF BY MONDAY MORNING. AN ASSOCIATED WEATHER FRONT WILL
MOVE ACROSS THE NE GULF SUN NIGHT AND ON SHORE THE NORTHERN
PANHANDLE MON.  

$$

PKZ310-141400-
GULF OF ALASKA NORTH OF 55 DEGREES NORTH AND EAST OF 144 DEGREES
WEST-
440 PM AKDT SUN MAY 13 2012 

UPDATED

...GALE WARNING TONIGHT...

.TONIGHT...S WIND INCREASING TO 35 KT BY LATE EVENING...THEN
DIMINISHING TO 25 KT LATE. SEAS BUILDING TO 14 FT. RAIN IN THE
EVENING.
.MON...SW WIND 25 KT. SEAS 11 FT. S SWELL. 
.MON NIGHT...W WIND 30 KT. SEAS 10 FT. 
.TUE...W WIND 25 KT. SEAS 9 FT. 
.TUE NIGHT...W WIND 20 KT. SEAS 8 FT. 
.WED...W WIND 20 KT. SEAS 6 FT. 
.THU...W WIND 15 KT. SEAS 6 FT OR LESS. 
.FRI...SE WIND 25 KT. SEAS 6 FT. 

$$

330 
FZAK67 PAJK 141132
OFFAJK

OFFSHORE WATERS FORECAST
NATIONAL WEATHER SERVICE JUNEAU AK
400 AM AKDT MON MAY 14 2012 

OFFSHORE WATERS FORECAST FOR GULF OF ALASKA EAST OF 144W

WIND FORECASTS REFLECT THE PREDOMINANT SPEED AND DIRECTION
EXPECTED. SEA FORECASTS REPRESENT THE AVERAGE OF THE HIGHEST
ONE-THIRD OF THE COMBINED WINDWAVE AND SWELL HEIGHT.

PKZ398-150100-
400 AM AKDT MON MAY 14 2012 
.SYNOPSIS FOR THE EASTERN GULF OF ALASKA...
A WEAKENING LOW IN THE NORTHERN GULF WILL SLOWLY DRIFT E TO THE
NE GULF THROUGH LATE MON NIGHT. THE ASSOCIATED WEATHER FRONT
WILL MOVE ACROSS THE NE GULF COAST AND THE NORTHERN PANHANDLE
THROUGH EARLY TUE MORNING. THE LOW WILL MOVE ONSHORE OVER THE
CENTRAL PANHANDLE TUE MORNING THEN DISSIPATE TUE AFTERNOON. HIGH
PRESSURE WILL CONTINUE TO BUILD OVER THE GULF THROUGH WED.  

$$

PKZ310-150100-
GULF OF ALASKA NORTH OF 55 DEGREES NORTH AND EAST OF 144 DEGREES
WEST-
400 AM AKDT MON MAY 14 2012 

.TODAY...SW WIND 25 KT. SEAS 10 FT. SW SWELL. 
.TONIGHT...SW WIND 30 KT. SEAS 11 FT. 
.TUE...W WIND 25 KT. SEAS 10 FT. SW SWELL. 
.TUE NIGHT...W WIND 25 KT. SEAS 8 FT. 
.WED...W WIND 20 KT. SEAS 7 FT. 
.THU...W WIND 15 KT. SEAS 6 FT OR LESS. 
.FRI...E WIND 25 KT. SEAS 6 FT OR LESS. 

$$

SOUTHEAST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE JUNEAU AK
356 PM AKDT SUN MAY 13 2012

.SHORT TERM...A MATURE 1008 MB NEAR PADQ IS INTERACTING WITH A
CYCLOGENTIC SYSTEM TO THE SE. THIS CYCLOGENETIC WAVE HAS A
FRONTAL INFLECTION ABOUT 200 NM SE OF PADQ AT THIS TIME, BASED ON
THE INTERPRETATION OF THE IR LOOP AND RELATIONSHIP TO MODEL
FIELDS. GFS IS EASY TO RECONCILE WITH THIS STAGE OF CYCLONE
EVOLUTION, WITH EC A GOOD SECOND. THE CYCLOGENTIC LOW WILL DEEPEN
TO ABOUT 1008 MB 100 NM S OF PAWD ABT 09Z THIS EVENING, AS THE
ORIGINAL LOW WEAKENS. IT HAS VALUES BETWEEN THE NAM AND EC
MODELS. THE QPF VALUES FOR THE PAYA VCNTY WILL BE MODERATE
FMH1 (WHAT THE PUBLIC  CALLS HEAVY RAIN) BEGINNING TONIGHT AND
CONTINUING INTO MON).

 WE ARE GOING TO NAME THE FRONTAL WAVE "WAVE ONE". A SECOND
FRONTAL WAVE INVOF 45/142 WILL BE CALLED "WAVE TWO".

 THE PAIR OF LOWS DISCUSSED ABOVE HAS AN ASSOCIATED CYCLONIC FLOW
OVER THE ENTIRE GLFALSK AND ALL SE AK. THE MOST IMPORTANT
MODIFICATION TO THIS CIRCULATION IS A RIDGE EXTENDING N ALONG THE
PNHDL FM THE S. THIS RIDGE WAS INITIALLY BUILT UP IN THE LEE OF A
CDFNT THAT MADE LANDFALL OF THE PNHDL LAST NIGHT. THAT FRONT NOW
HAS REACHED NRN B.C. BUT ALSO HAS THE FRONTAL WAVE TWO WITH AN
INFLECTION POINT AT ABT 45/142. THE RIDGE ALONG THE PNHDL IS NOW
BEING INTENSIFIED BY WAVE TWO.

 MODELS: GFS AND EC WERE BOTH HAD A GOOD INITIALIZATION BASED ON
500 MB VORT TO IR. THE NAM WAS A GOOD THIRD PLACE BUT WAS USED
FOR ONLY A MINORITY OF FIELDS AS THAT MODEL MSLP SEEMS TO NOT BE
RESPONDING TO THE SFC PRESSURE RIDGE BLDG ALONG THE PNHDL FM THE
S AS WELL AS THE GFS.

 THE CYCLOGENTIC SYSTEM WITH WAVE ONE HAS THICKNESS VALUES LOW
ENOUGH TO HAVE SNOW MIXED IN TO THE RAINFALL IN WRN ZONE
17 MONDAY, BUT NOT AT PAYA.

 &&

 .LONG TERM...GOOD UPPER LEVEL MODEL AGREEMENT THROUGH THE MIDDLE
OF NEXT WEEKEND. AGREEMENT A LITTLE LESS SO AT THE SURFACE. A LOW
CURRENTLY FORMING ON A FRONTAL BOUNDARY IN THE WESTERN GULF WILL
TRACK EAST TOWARDS THE CENTRAL OUTER COAST EARLY IN THE WEEK.
WHILE THIS FEATURE IS NOT VERY STRONG OR DEEP, SMALL MODEL
DIFFERENCES WITH RESPECT TO TRACK WILL HAVE A MUCH LARGER IMPACT
ON WIND DIRECTION AND SPEED AS THE LOW CROSSES THE OUTER COAST.
GFS IS A SLOW OUTLIER WITH ALL REMAINING MODELS CLUSTERED FARTHER
TO THE EAST AND FASTER TO MAKE LANDFALL ALONG THE CENTRAL OUTER
COAST MID MORNING TUESDAY. PREVIOUS FORECAST REFLECTS THIS ALREADY
AND HAVE KEPT IT SO.

HIGH PRESSURE OVER THE GULF AND LOW PRESSURE OVER WESTERN CANADA
WILL DOMINATE MUCH OF THE REMAINING WEEK. THIS SHOULD PRODUCE A
NORTHWEST ONSHORE FLOW AND MARINE STRATUS ALONG THE OUTER COAST.
SHOWER ACTIVITY WILL PERSIST ON WEDNESDAY, THEN DIMINISH FROM
NORTH TO SOUTH ON THURSDAY WITH A GOOD CHANCE FOR A DRY DAY ON
FRIDAY FOR MOST LOCATIONS.

NEXT WELL ORGANIZED FRONT ARRIVES ALONG THE OUTER COAST NEXT
WEEKEND WITH STRONG SOUTHEASTERLY SMALL CRAFT WINDS OVER THE
COASTAL MARINE ZONES IN ADVANCE OF THE FRONT.

 USED ECMWF FOR PRESSURE AND POP THROUGH WEDNESDAY NIGHT. WIND
SPEEDS BIASED TOWARDS 12Z ECMWF THROUGH WEDNESDAY EVENING, THEN
GFS FRIDAY NIGHT THROUGH SUNDAY AFTERNOON. BLENDED HPC, ECMWF,
AND GFS THURSDAY THROUGH SATURDAY NIGHT. STRAIGHT HPC FOR DAY 8.
TEMPS ADJUSTED WITH BIAS CORRECTED GFS40 AND BIAS CORRECTED MOS.

.AJK WATCHES/WARNINGS/ADVISORIES...
PUBLIC...NONE.
MARINE...GALE WARNING FOR PKZ051-052.
         SMALL CRAFT ADVISORY FOR PKZ012-033-034-043.
         SMALL CRAFT ADVISORY DUE TO SEAS FOR PKZ041-042.

&&

JBT/FRITSCH