Small Craft Advisory 140, NWS Anchorage, AK

AREA FORECAST DISCUSSION
SOUTHCENTRAL AND SOUTHWEST ALASKA
400 AM AST WED FEB 7 2007

.DISCUSSION...A BROAD TROUGH IN THE WESTERN BERING AND HIGH PRESSURE
OVER THE ARCTIC OCEAN REMAIN FIRMLY IN PLACE. BOTH THE NAM AND GFS
HAVE A DECENT HANDLE ON THESE FEATURES...BUT THE DEVIL IS IN THE
DETAILS...AND FOR THAT WE WILL STICK WITH THE GFS.

EAST OF THE ALASKA RANGE...A WEAK FRONTAL BOUNDARY CONTINUES TO HANG
OUT FROM SE TO NW IN THE GULF. A CLOSED LOW TRIES TO GET ORGANIZED IN
THE VICINITY OF KODIAK ISLAND WITH PRECIP SPREADING SLOWLY N ON THE
SE TRAJECTORY AROUND THE LOW. JUST HOW FAR NORTH THE PRECIP REACHES
WILL HINGE GREATLY ON WHERE A SHORTWAVE CURRENTLY IN EXTREME NW
CANADA TRAVELS. THE GFS HAS THE WAVE DROPPING INTO THE CENTRAL PART
OF THE STATE LATER TODAY WITH THE NAM POSITION JUST A BIT FURTHER
NORTH. SINCE THE GFS SEEMED TO HAVE INITIALIZED BETTER WITH MOISTURE
FIELDS THIS MORNING...I AM INCLINED TO BELIEVE ITS TRACK. THAT BEING
SAID...THE SLIGHTEST JOG OF THE WAVE IN EITHER DIRECTION WILL
INFLUENCE WHO SEES THE SNOW (OR RAIN...DEPENDING ON YOUR LOCATION).

PRECIPITATION IS CURRENTLY FALLING OVER KODIAK ISLAND AND IS
SPREADING ONTO THE SOUTHERN TIP OF THE KENAI PENINSULA. A DRY LOW
LEVEL NORTHERLY FLOW WILL TEND TO HOLD THE ADVANCING MOISTURE AT BAY
TODAY...ESPECIALLY FROM ANCHORAGE NORTHWARD. AS THE AFOREMENTIONED
SHORTWAVE PUSHES WEST THROUGH THE STATE...ANOTHER SURGE OF MOISTURE
WILL TRY TO SPREAD NORTH TONIGHT THROUGH THU NIGHT. AT THIS
TIME...SOME LIGHT SNOW SHOULD WORK INTO THE ANCHORAGE BOWL AND
MAT-SU VALLEY. HIGH PRESSURE ALOFT TAKES CONTROL YET AGAIN BEGINNING
FRIDAY...SIGNALING AN END TO THE PRECIP FOR MUCH OF THE WEEKEND.

WEST OF THE ALASKA RANGE...A BROAD AREA OF LOW PRESSURE STAYS PUT
OVER THE BERING WITH CONTINUED UNSETTLED WEATHER. NO HEAVY PRECIP OR
UNUSUALLY STRONG WINDS ARE ANTICIPATED AS BOTH SFC AND UPPER LEVEL
FEATURES ARE RELATIVELY WEAK.

.AER/ALU...WATCH/WARNING SUMMARY.
PUBLIC...NONE.
MARINE...GALE 175 176 138.
FIRE WEATHER...NONE.

JCA