Gale Warning 18, NWS Juneau, AK

SOUTHEAST ALASKA FORECAST DISCUSSION
1100 AM AST SUN JAN 6 2008

.SYNOPSIS...
.SHORT RANGE...THE MORNING SATELLITE LOOP SHOWS A WEAKENING
TROUGH OF LOW PRESSURE SLOWLY DRIFTING NORTH ACROSS THE PANHANDLE
WITH A LITTLE BREAK IN OVERCAST OVER SOUTHERN ZONES.  THE 12Z GFS
KEEPS THE SAME SYNOPTIC CONDITION FROM THE PREVIOUS RUN.  NO NEED
TO MAKE ANY BIG CHANGES.  WILL GO WITH A COSMETIC TOUCH OVER THE
INHERITED GRIDS.  THIS CURRENT TROUGH WILL CONTINUE TO WEAKEN AND
MOVE NORTH THROUGH MONDAY MORNING WITH HEAVY SNOW FOR YAKUTAT AND
GUSTAVUS ZONES.  THIS DRIFTING TROUGH SEEMS LIKE TO GENERATE A
WELL ORGANIZED LINE OF LIFTING ACROSS THE NORTHERN ZONES.  WITH
AN INCREASING SOUTHEAST FLOW OVER THE AREA...THE AFTERNOON
FORECAST PACKAGE WILL NEED TO INCLUDE A SNOW ADVISORY FOR
GUSTAVUS AND A HEAVY SNOW FOR YAKUTAT.  CENTRAL AND SOUTHERN
ZONES MAY RECEIVE 1 TO 2 INCHES OF SNOW.

A DEVELOPING LOW WILL MOVE INTO THE CENTRAL GULF MONDAY MORNING
WILL PUSH A FRONT INTO THE SOUTHERN ZONES THROUGH LATE MONDAY.
WINDS WILL PICK UP OVER THE SOUTHERN OUTSIDE WATERS AND CLARENCE
STRAIT TO  GALE FORCE LATE MONDAY.  ZONES 27 AND 28 LOOK LIKE TO
MEET THE WIND ADVISORY CRITERIA LATE MONDAY EVENING.  AHN

.LONG RANGE...THE MODELS THIS MORE ARE IN FAIR AGREEMENT THROUGH
MOST OF THE WEEK. THERE IS SOME DIFFERENCES WITH WHERE THE LOW
LIFTING INTO THE GULF MON NIGHT WILL TRACK THE REST OF THE WEEK.
IT LOOKS LIKE THE GFS IS THE OUTLIER WITH KEEPING THE LOW FURTHER
SOUTH IN THE CENTRAL GULF WHILE THE ECMWF AND UKMET WEAKEN THE
LOW TO A TROF AS IT LIFTS INTO THE NORTHERN GULF LATE TUE NIGHT
INTO WED. AFTER COORDINATING WITH ANC AND NCEP WILL GO WITH THE
FURTHER NORTH SOLUTION SO WILL BLEND 70 PERCENT ECMWF AND THE 30
PERCENT 12Z GFS. THE LARGEST IMPACTS TO THE FORECAST WILL BE IN
THE WINDS AS THEY WILL DIMINISH SOONER THROUGH THE WEEK THAN
PREVIOUS PACKAGE.

A 975 MB LOW WILL BE LIFTING OUT OF THE NORTH PACIFIC INTO THE SE
GULF THROUGH MON NIGHT. THIS LOW WILL KEEP THE STRONG ADVY WIND
GUSTS GOING OVER THE SOUTHERN COASTAL ZONES THROUGH THE NIGHT.
THESE STRONG GUSTS WILL MOVE NORTH THROUGH MON NIGHT TO INCLUDE
ZONE 23 26 29. THE REST OF THE PANHANDLE WILL SEE BREEZY TO WINDY
CONDITIONS THROUGH TUE WITH ADVY GUSTS NEAR PAGY THROUGH TUE. THE
MARINE AREAS WILL SEE GALES OVER THE COASTAL AREAS WITH SMALL
CRAFTS OVER THE INSIDE WATERS WITH STRONGER GUSTS OUT OF INTERIOR
PASSES MON NIGHT THROUGH TUE AFTERNOON.

AS FOR PRECIP...THE NORTHERN AREAS WILL REMAIN ON THE DRY SIDE
THROUGH TUE MORNING BEFORE THE MOISTURE LIFTS NORTH BY THE
AFTERNOON. THE SOUTHERN COASTAL AREAS WILL SEE RAIN THROUGH MON
NIGHT WITH A MIX OF RAIN AND SNOW OVER THE CENTRAL AREAS
DEVELOPING BY TUE MORNING. AMOUNTS WILL NOT BE THAT MUCH AS BY
THE AFTERNOON MOST OF THE MIX PRECIP WILL HAVE CHANGED TO ALL
RAIN. THE NORTHERN AREAS WILL SEE MAINLY ALL SNOW WITH SOME MIX
PRECIP THROUGH TUE AFTERNOON WITH AMOUNTS ON THE LOW SIDE.

SHOWERS WILL CONTINUE TO MOVE OVER THE PANHANDLE THROUGH THE REST
OF THE WEEK AS THE LOW MOVES INTO THE NORTHERN GULF AND DISSIPATE
BY WED NIGHT AS THE UPPER LEVEL TROF MOVES INLAND. THESE SHOWERS
WILL BE SOLID AS IT WILL BE ON THE COLDER SIDE.

THERE IS SOME DIFFERENT SOLUTIONS WITH A LOW THAT WILL MOVE JUST
SOUTH OF THE PANHANDLE ON WED NIGHT INTO THURSDAY. THE ECMWF
BRINGS THIS LOW OVER THE SOUTHERN AREAS OF THE SE AK BUT THE GFS
MOVES THIS FEATURE WELL TO THE SOUTH OF THE FORECAST AREA...WILL
NOT CHANGE THIS PART OF THE FORECAST THROUGH DAY 7 AS THERE IS
LARGE SPREADS IN THE EVOLUTION OF THE WEATHER PATTERN AS THE
MODELS ARE ALSO SHOWING ANOTHER FAIRLY STRONG LOW MOVING INTO THE
GULF FOR NEXT WEEKEND.

.AJK...WATCHES/WARNINGS/ADVISORIES
PUBLIC...HVY SNOW WRNG FOR AKZ017 THRU MON AM. ...SNOW ADVY FOR
AKZ020 THROUGH MON PM.
MARINE...GALE WRNG FOR PKZ041-036 MON. ...SCA FOR REST OF CSTL
WTRS.