Gale Warning 181, NWS Anchorage, AK

AREA FORECAST DISCUSSION
SOUTHCENTRAL AND SOUTHWEST ALASKA
500 PM AST MON FEB 11 2008

.MODEL DISCUSSION...
IT LOOKS LIKE THE MODELS BACK ON TRACK AND ARE IN GOOD AGREEMENT.
ONLY GET THE NAM MODEL THRU 09Z WED.

.ANALYSIS AND UPPER LEVELS...
THE UPPER LOW OVER NORTON SOUND STILL IS MOVING WEST. AN UPPER RIDGE
IS BUILDING OVER BRITISH COLUMBIA AND THE YUKON TERRITORY. SOUTHERLY
FLOW OFF THE NORTH PACIFIC IS STARTING TO SET UP.

A WEAK LOW PRESSURE SYSTEM OVER CENTRAL GULF OF ALASKA HAD FEED
WARMER MOIST AIR ACROSS PRINCE WILLIAM SOUND THE KENAI PENINSULA. A
WARM FRONT WAS FORMED OVER THE ANCHORAGE BOWL AND WESTERN KENAI
PENINSULA SUNDAY NIGHT AS THE WARM AIR COLLIDED WITH THE PRE-EXISTING
COLD AIR. MOST OF THE HEAVIER SNOW FELL ALONG THE FRONT SUNDAY NIGHT
AND EARLY MONDAY MORNING. THE WARM FRONT MOVED WEST INTO THE COOK
INLET AND SOUTHERN SUSITNA VALLEY BY LATE MORNING. OTHERWISE, SNOW
WAS MOSTLY CONFINED TO PRINCE WILLIAM SOUND.

SOUTHWEST ALASKA CONTINUES TO BE CLEAR AND COLD.

.SHORT TERM FORECAST...
THE UPPER LOW OVER WESTERN ALASKA WILL BECOME NEARLY STATIONARY JUST
NORTH OF SAINT LAWRENCE ISLAND TUESDAY AND WEDNESDAY. AN UPPER SHORT
WAVE TROUGH OVER BRISTOL BAY WILL MOVE EAST THROUGH THE KENAI
PENINSULA, ANCHORAGE BOWL AND SOUTHERN SUSITNA VALLEY TONIGHT AND
THROUGH PRINCE WILLIAM SOUND MONDAY AFTERNOON THEN WEAKEN ALONG THE
CANADIAN BORDER MONDAY NIGHT. THE SOUTHERLY FLOW OF THE GULF WILL
WEAKEN AS THE UPPER TROUGH MOVES THROUGH THE AREA TONIGHT AND TUESDAY
BUT WILL STRENGTHEN AGAIN TUESDAY NIGHT AND WEDNESDAY.

SOUTHCENTRAL ALASKA AND THE GULF...
THE WEAK LOW SOUTH OF SEWARD WILL MOVE NORTH INTO THE KENAI PENINSULA
THEN DISSIPATE OVER THE COPPER RIVER BASIN TUESDAY. THIS WILL
COINCIDE WITH THE PASSAGE OF THE UPPER TROUGH THROUGH THE AREA AND
MAY AMPLIFY THE SNOWFALL OVER THE AREA. SNOW ADVISORIES HAVE BEEN
ISSUED FOR THE ANCHORAGE BOWL AND THE MATANUSKA VALLEY FOR TONIGHT
THROUGH TUESDAY MORNING. SNOW WILL BECOME SNOW SHOWER TUESDAY
AFTERNOON AND NIGHT.

THE NEXT MAJOR STORM MOVING TO ABOUT 200 MILE SOUTHWEST OF KODIAK
ISLAND WEDNESDAY AFTERNOON WILL BRING MORE WARM AIR AND MOIST INTO
SOUTHCENTRAL ALASKA. SNOW WILL MOVE INTO KODIAK ISLAND TUESDAY NIGHT
BUT WILL CHANGE TO RAIN WEDNESDAY MORNING. SOUTHEAST FLOW MOVING INTO
PRINCE WILLIAM SOUND WILL BRING RAIN AND SNOW INTO THE EASTERN KENAI
PENINSULA AND SOUTHERN SOUND WEDNESDAY. SIGNIFICANT AMOUNTS OF SNOW
COULD ALSO FALL ALONG THE WEST SIDE OF THE SUSITNA VALLEY.

SOUTHWEST ALASKA...
MOST OF SOUTHWEST ALASKA WILL REMAIN COLD AND DRY THROUGH TUESDAY AS
HIGH PRESSURE BUILDS OVER THE KUSKOKWIM VALLEY TUESDAY. GUSTY NORTH
WINDS ALONG THE COAST WILL DIMINISH THIS EVENING. MORE CLOUDS, SNOW
AND WARMER TEMPERATURES WILL SPREAD INTO BRISTOL BAY FROM THE SOUTH
TUESDAY NIGHT AND INTO THE REST OF AREA WEDNESDAY.

ALEUTIANS AND BERING SEA...
THE EAST TO NORTHEAST FLOW OVER THE BERING SEAS WILL BECOME NORTHERLY
TUESDAY. SCATTERED SNOW SHOWERS WILL PERSIST OVER BERING SEA THROUGH
WEDNESDAY. GALE FORCE WINDS WILL MOVE INTO THE CENTRAL AND EASTERN
ALEUTIANS TUESDAY AND TUESDAY NIGHT.

.LONG TERM FORECAST...
THE UPPER LOW NEAR SAINT LAWRENCE ISLAND WILL PERSIST THROUGH FRIDAY
THEN WILL MOVE INTO SIBERIA SATURDAY. AN UPPER TROUGH EXTENDING SOUTH
FROM THE CENTER WILL ROTATE EAST INTO SOUTHWEST ALASKA THURSDAY NIGHT
AND INTO SOUTHCENTRAL ALASKA FRIDAY. CLOUDS AND AREAS OF SNOW WILL
PERSIST OVER MOST OF SOUTHERN ALASKA THROUGH THURSDAY. A SURFACE
RIDGE WILL BUILD INTO EASTERN ALASKA FRIDAY BRIEFLY CLEARING THE
CLOUDS BUT ANOTHER STORM IS EXPECTED INTO THE GULF SATURDAY.

.AER/ALU...WATCH/WARNING SUMMARY
PUBLIC...BLIZZARD WARNING NEAR THOMPSON PASS AND KEYSTONE CANYON.
MARINE...STORMS 170
         GALES 130, 132, 150, 155, 160, 165, 171, 172
FIRE WEATHER...NONE.

NM FEB 08