Gale Warning 370, NWS Juneau, AK

009 
FZAK67 PAJK 051116
OFFAJK

OFFSHORE WATERS FORECAST
NATIONAL WEATHER SERVICE JUNEAU AK
400 AM AKDT SAT NOV 5 2011 

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.

PKZ398-060100-
400 AM AKDT SAT NOV 5 2011 
.SYNOPSIS FOR THE EASTERN GULF OF ALASKA...
A LOW OVER THE NORTHEAST GULF WILL DRIFT TO THE SOUTHEAST AND
WEAKEN THROUGH SATURDAY. A FRONT WILL APPROACH THE PANHANDLE
FROM THE WEST ON SUNDAY. 

$$

PKZ310-060100-
GULF OF ALASKA NORTH OF 55 DEGREES NORTH AND EAST OF 144 DEGREES
WEST-
400 AM AKDT SAT NOV 5 2011 

.TODAY...W WIND 30 KT. SEAS 15 FT. 
.TONIGHT...SW WIND 25 KT. SEAS 13 FT. W SWELL. 
.SUN...SW WIND 30 KT. SEAS 13 FT. RAIN.
.SUN NIGHT...W WIND 30 KT. SEAS 15 FT. RAIN.
.MON...W WIND 30 KT. SEAS 17 FT. 
.TUE...NW WIND 25 KT. SEAS 12 FT. 
.WED...SW WIND 30 KT. SEAS 11 FT. 

$$

SOUTHEAST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE JUNEAU AK
555 AM AKDT FRI NOV 4 2011

.SHORT TERM...A WELL DEFINED BAROCLINIC CLOUD SHIELD HAS PUSHED
IN OVER THE PANHANDLE OVERNIGHT AND IS NOW MOSTLY OVER BRITISH
COLUMBIA. THE ASSOCIATED OCCLUDED FRONT IS STILL WELL OFFSHORE
BUT WILL ARRIVE OVER THE OUTER COAST LATER TODAY. THE PARENT LOW
WILL TRACK TO THE EAST ALONG THE NORTHERN PORTION OF THE GULF
THROUGH THE DAY AND THEN BEGIN TO DRIFT TO THE SOUTHEAST OVER THE
EASTERN GULF OVERNIGHT FRIDAY NIGHT WHILE WEAKENING. MEANWHILE,
HIGH PRESSURE OVER CANADA THAT BROUGHT COLD SURFACE TEMPERATURES
TO SOUTHEAST ALASKA EARLIER THIS WEEK HAS BEGUN TO WEAKEN AND SAG
TO THE SOUTHEAST. PRECIPITATION IN THE FORM OF SNOW BEGAN
OVERNIGHT OVER WESTERN AND NORTHERN ZONES AND WILL CONTINUE TO
MAKE PROGRESS TO THE SOUTH AND EAST AS THE DAY PROGRESSES.
BELIEVE ENOUGH COLD AIR WILL REMAIN IN PLACE OVER THE FAR
NORTHERN INNER CHANNELS, TO INCLUDE JUNEAU, THAT PRECIP WILL
REMAIN AS SNOW THROUGH THE DAY AND NIGHT. HAVE UP TO 5 INCHES IN
THE FORECAST FOR JUNEAU WITH LESSER AMOUNTS ELSEWHERE OVER THE
COURSE OF THE NEXT 24 HOURS. ELSEWHERE, WARM AIR ADVECTION
ASSOCIATED WITH THE FRONT WILL RESULT IN A TRANSITION TO A
RAIN-SNOW MIX OVER MOST LOCATIONS LATER TODAY, AND THEN TO
STRAIGHT RAIN LATER ON. DIURNAL TEMPERATURE VARIATIONS WILL BE
SLIGHT AND SOME LOCATIONS WILL SEE A GRADUAL RISE THROUGH THE
NIGHT AS WARMER LOW LEVEL AIR PUSHES THE ARCTIC FRONT TO THE
EAST.

WINDS ASSOCIATED WITH THE APPROACHING FRONT ARE NOT NEARLY AS
STRONG AS WHAT SOUTHEAST ALASKA HAS EXPERIENCED OVER THE PAST
SEVERAL WEEKS. SOUTHEASTERLY GALES IN ADVANCE OF THE FRONT EXTEND
AS FAR SOUTH AS CAPE EDGECUMBE OVER THE COASTAL MARINE ZONES WITH
SMALL CRAFT WINDS AND SEAS FARTHER SOUTH. HAVE LOW END GALES IN
THE FORECAST FOR LATER THIS MORNING FOR CROSS SOUND AND FOR FAR
NORTHERN PORTIONS OF WEST ARM IN GLACIER BAY. LATER TONIGHT, AM
EXPECTING LOW END GALES OVER CLARENCE STRAIT AS WELL. SMALL CRAFT
ADVISORIES AT VARIOUS TIMES FOR THE REMAINING INNER CHANNELS
EXCEPT UPPER AND LOWER LYNN CANAL AND NORTHERN CHATHAM STRAIT
WHERE WINDS NOT EXPECTED TO EXCEED 20 KTS. HAVE ALSO INCLUDED A
STRONG WIND HEADLINE FOR ZONES 22 AND 23 FOR LATER THIS MORNING
FOR A BRIEF PERIOD OF 40 MPH GUSTS IN ADVANCE OF THE FRONT.
STRONGEST GUSTS WILL BE LIMITED TO THE OUTER COAST.

USED ECMWF AS A FOUNDATION FOR THE SHORT TERM FORECAST BASED ON
SUPERIOR DEPICTION OF MID LEVEL MOISTURE, JET STREAM STRENGTH AND
LOCATION, AND SURFACE PRESSURE INITIALIZATION. USED NAM WIND
SPEEDS TO CAPTURE HIGH RESOLUTION WIND DETAILS. BLENDED GFS, NAM,
AND GEM FOR POP GRIDS AND QPF. TEMPERATURES, SNOW LEVELS, AND DEW
POINTS FROM NAM. FORECAST CONFIDENCE IS ABOVE AVERAGE.

.LONG TERM...A PROGRESSIVE PATTERN OF POLAR FRONT ZONE WAVES WILL
PERSIST WITH STRONGEST SUSTAINED WINDS TYPICALLY OF 30 KT.
A SMALL BUT SIGNIFICANT CHANGE WAS MADE TO THE TEMPERATURE
FORECASTS FOR SAT AND SAT NIGHT. THIS RAISING OF FORECAST
TEMPERATURES IS ONLY 1-2F AND IS ASSOCIATED WITH A MORE RAPID
CHANGE FROM SNOW TO RAIN FOR SAT AND SAT NIGHT. OTHER CHANGES IN
THE LONG RANGE PACKAGE ARE ARE SMALL. CONFIDENCE IS AVERAGE. THE
MOST USED MODEL WAS THE 04.00 EC, BUT SEVERAL OTHERS WERE USED AS
MENTIONED IN A SECTION ON THE MODELS GIVEN BELOW.

THE SYSTEM IN THE GULF DISCUSSED IN THE SHORT RANGE SECTION ABOVE
HAS A 985 MB LOW ABOUT 100 NM S OF PAWD AT THIS TIME. THIS LOW
WILL FILL WHILE TRACKING E. 12Z SAT THE MSLP REMAINS OF THIS
SYSTEM WILL BE SEVERAL SHALLOW SEVERAL WEAK LOW PRESSURE OF
CENTERS IN THE VICINITY OF A LINE BETWEEN PAWD AND HAIDA GWAII,
WITH NO CENTER DEEPER THAN 992 MB.

A 500H RIDGE MOVING EWD ACROSS THE GULF WILL REACH LINE EXTENDING
N FM NPAC TO OVER PACV AT 00Z SUN. AS A RESULT, THE WEAK LOWS IN
THE ERN GULF, DISCUSSED IN THE PARAGRAPH ABOVE, WILL DISSIPATE.
THE RIDGE ALOFT WILL SLOWLY LOSE AMPLITUDE BY THE TIME IT REACHES
A PASI-PAJN LN 12Z SUN.

MODELS: A CONSENSUS AMONG EC/UKMET/NAM AND THE SREF WAS USEFUL.
TERRAIN ISSUES ON SHALLOW LOW LEVEL LOWS IN EASTERN GULF RESULTED
IN AN EMPHASIS ON THE EC AND NAM SOLUTIONS.

.AJK WATCHES/WARNINGS/ADVISORIES...
PUBLIC...STRONG WIND FROM 10 AM THIS MORNING TO 1 PM AKDT THIS AFTERNOON
     FOR AKZ022-023.
MARINE...GALE WARNING FOR PKZ011-022-036-043-051-052.
         SMALL CRAFT ADVISORY FOR PKZ021-031-033>035-041-042.

&&

FRITSCH/JBT