High Wind in Alaska, February 3, 2003

SOUTH/SOUTHWEST ALASKA FORECAST DISCUSSION
900 PM AST SUN FEB 2 2003

ANALYSIS AND FORECAST...THE MAIN UPPER LEVEL TROFF EXTENDS FROM
THE ARCTIC SOUTH THROUGH THE EASTERN BERING SEA TO ANOTHER UPPER
CENTER LOCATED JUST SOUTH OF THE EASTERN ALEUTIANS. THIS WILL
CONTINUE TO BE THE FOCUS THAT OUR WEATHER ACTIVITY IS CENTERED
AROUND. THE UPPER CENTER WILL PERSIST BUT WEAKEN SLIGHTLY THROUGH
MON EVENING AS THE UPPER TROFF CONTINUES TO DIG TO THE SOUTH. AS
THE TROFF DIGS SOUTH A CENTER FORMS IN IT NEAR ST MATTHEW ISLAND
BY TUE AFTERNOON. THIS WILL DRIVE THE UPPER LEVEL COLD AIR FROM
ASIA INTO THE CENTRAL BERING SEA THROUGH TUE. AT THE SURFACE THIS
WILL SUPPORT THE ONSLAUGHT OF SURFACE LOWS FROM THE NORTH PACIFIC
INTO THE ALASKA PENINSULA  AND SOUTHWEST ALASKA THROUGH MID WEEK.
THIS WILL RESULT IN A STRONG WARM MOIST SOUTHERLY FETCH INTO THE
GULF COAST THROUGH MID WEEK. THIS WILL DRIVE CLOUDS AND
PRECIPITATION INTO THE GULF COAST REGION THROUGH MID WEEK AND
DRIVE THE FREEZING LEVELS UP TO 5000 FT OVER THE KENAI PENINSULA
TO AROUND 2000 TO 3000 FT IN THE COPPER RIVER BASIN AND THE
SUSITNA VALLEY. THEREFORE EXPECT THE PRECIPITATION OVER THE KENAI
TO AND SOUTH CENTRAL ALASKA TO RAPIDLY CHANGE TO RAIN AND BE A
MIXTURE OF RAIN AND SNOW IN THE SUSITNA VALLEY AND THE NORTHERN
SOUND MON. STRONG SOUTH TO SOUTHEAST FLOW WILL RESULT IN THE
TYPICAL DOWN SLOPE AFFECT FOR THE WEST SIDE OF THE KENAI
MOUNTAINS AND TALKEETNA MOUNTAINS AS WELL AS ACROSS THE CHUGACH
MOUNTAINS IN THE COPPER RIVER BASIN. MODEL FORECAST VALUES OF
NEARLY 2 INCHES OF LIQUID PRECIPITATION IN THE SOUND BY MON
AFTERNOON WITH SIGNIFICANTLY LOWER AMOUNTS OF AROUND 1/4 OF AN
INCH INLAND. BY MON NIGHT INTO TUE MORNING EXPECT ANOTHER 2
INCHES OF LIQUID PRECIPITATION IN THE SOUND AND NORTH GULF COAST.

ACROSS THE SOUTHWEST ZONES EXPECT THE BRISTOL BAY REGION TO PICK
UP PRECIPITATION MAINLY ALONG THE NORTHERN MOUNTAINS AS THE FRONT
PUSHES THROUGH BY MON MORNING. POST FRONTAL STRONG SOUTH FLOW AND
THE DRY SLOT WILL RESULT IN A BREAK IN THE PRECIPITATION MON
AFTERNOON FOR BRISTOL BAY, BUT THE FRONT WILL PUSH TO THE
KUSKOKWIM DELTA AND VALLEY. EXPECT SNOW IN THE DELTA TO CHANGE TO
RAIN AND SNOW AND EXPECT SNOW IN THE KUSKOKWIM VALLEY INITIALLY
WITH THE FRONT TO END IN THE AFTERNOON DUE TO THE STRONG DOWN
SLOPE ACROSS THE ALASKA RANGE AND POST FRONTAL DRYING.

THE FIRST SURFACE LOW MOVES TO THE EASTERN ALEUTIANS WITH THE
FRONT PUSHING NORTH AND ANOTHER LOW FORMING ON THE FRONT ALONG HE
COAST OF THE DELTA. THIS WILL KEEP THE PRIBLOFS IN THE GUSTY
NORTH WINDS AND SNOW TROUGH MON. THE NORTH WINDS WILL DIMINISH
TUE AFTERNOON. EXPECT THE NORTH FLOW TO PERSIST ACROSS THE
ALEUTIAN CHAIN WITH THE LOW LEVEL COLD ADVECTION CONTINUING. WE
WILL ALSO SEE HEAVY FREEZING SPRAY ACROSS THE BERING SEA OFFSHORE
AS IT COOLS DOWN AND THE NORTH WINDS PERSIST THROUGH TUE.

.AFC...WATCH/WARNING SUMMARY
PUBLIC...NONE.
MARINE...GALE 8 12A 12A1 12B 13 15 5AB 6A 3ABC 4 2B.
         HEAVY FREEZING SPRAY 15.
FIRE WEATHER...DONE.

SAM FEB 03