Gale Warning 117, NWS Juneau, AK

SOUTHEAST ALASKA FORECAST DISCUSSION
1100 AM ADT SAT MAR 15 2008

.SYNOPSIS...
.SHORT RANGE...SURFACE HIGH PRESSURE RIDGE MOVING ACROSS THE
EASTERN GULF AND SOUTHEAST ALASKA THROUGH SATURDAY EVENING.  NEXT
WEATHER FRONT ASSOCIATED WITH A LOW NEAR THE EASTERN ALEUTIANS
THAT IS SLOWLY DRIFTING EAST. THE FRONT ARCS ACROSS THE SOUTHWEST
MAINLAND INTO THE NORTHERN GULF AND THEN SOUTH TO THE NORTH
PACIFIC BEFORE CURLING BACK TO THE SOUTHWEST.  THERE IS WAVE ON
THE FRONT THAT THIS MORNING IN A LITTLE TO THE WEST OF BUOY
46085. THAT FEATURE WILL MOVE TO THE NORTHEAST GULF BY LATE
SUNDAY NIGHT AND WILL BE WHAT STARTS TO SPREAD SOME PRECIPITATION
INTO THE PANHANDLE REGION... MEANWHILE A STRONGER LOW DEVELOPING
ON THE FRONT WILL RUN ALONG IT AND MOVE TO THE NORTHEASTER GULF
BY SUNDAY MORNING. IT IS WITH THIS FEATURE THE MAJORITY OF THE
WEATHER WILL BE COMING FROM ON SUNDAY.  MODELS SETTLING ON IDEA
THAT LOW MAY JUMP PART INLAND TO NORTHERN BRITISH COLUMBIA AND
KEEP A SECOND PART OVER THE NORTHEAST GULF OF ALASKA.

WITH THE COLDER AIR THAT SPREAD IN UNDER THE RIDGE MAINLY OVER
THE NORTHERN PANHANDLE EXPECT TO SEE THE PRECIPITATION THERE TO
START AS SNOW OR EVEN STAY SNOW.

FLOW ABOUT THE LOW OVER THE NORTHEAST GULF SEEMS FAVORABLE TO
DROP AROUND 4 TO 6 INCHES OF SNOW OVER THE HOONAH AND HAINES
REGIONS AND A LITTLE LESS (2 TO 4 OR SO) ON SURROUNDING ZONES.
WILL HAVE TO KEEP AN EYE ON THIS TO SEE IF THE AMOUNT MAY NEED TO
BE INCREASED BUT WILL LEAVE AS IS FOR NOW.

GUSTY WINDS WITH THE FRONTAL BAND AND LOW SPREADING GALE FORCE
WINDS INTO THE OUTER WATERS TONIGHT TO SUNDAY. WITH SMALL CRAFT
LEVELS FOR THE MARINE AREAS OVER THE INNER WATERS.  GUSTS LOOK TO
BE SUFFICIENT TO MAINTAIN WIND ADVISORIES FOR THE COASTAL AREA
FROM CROSS SOUND SOUTH AND THE SOUTHERN INNER WATERS PUBLIC
ZONES.

.LONG RANGE...IMPROVED AGREEMENT BETWEEN GFS AND UKMET SINCE THE
00Z MODEL RUN. OVERALL VERY GOOD AGREEMENT AMONGST ALL TYPICALLY
USED MODELS THROUGH 19/00Z. AFTER THIS TIME...SOME DIFFERENCES
BEGIN TO EMERGE BETWEEN GFS AND ECMWF WHICH APPEAR TO ORIGINATE
WITH HOW EACH MODEL RESOLVES A SHORT WAVE UNDER CUTTING AN UPPER
LEVEL RIDGE OVER THE SEA OF OKHOTSK ON 18 MARCH. GFS ATTACHES IT
TO A MUCH STRONGER SHORT WAVE AS IT PASSES THROUGH THE TROUGH OF
THE PREVAILING LONG WAVE OVER SAKHALIN ISLAND. ECMWF...ON THE
OTHER HAND...COMPLETES THE UNDERCUT AND ATTACHES THE SHORTWAVE TO
THE NEXT DOWNSTREAM LONGWAVE OVER ALASKA. AS A RESULT...ECMWF
DIGS THE RESULTANT SHORT WAVE MUCH MORE DEEPLY INTO THE NORTHERN
PACIFIC SOUTH OF THE GULF OF ALASKA AND IS NOT NEARLY AS
NEGATIVELY TILTED AS THE GFS SOLUTION AT THIS SAME TIME. END
RESULT ..SMALL CRAFT PKZ011>013-031>036

BMB/FCF