Blizzard in Alaska, April 8, 2012

SOUTHCENTRAL AND SOUTHWEST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE ANCHORAGE AK
500 PM AKDT SAT APR 7 2012

.MODEL DISCUSSION...
MODELS CONTINUE TO REMAIN IN VERY GOOD AGREEMENT THROUGH MONDAY
THOUGH THE NAM IS MOVING THE LOW MOVE THE NORTHWEST PACIFIC A LITTLE
FASTER THAN THE ECMWF OR GFS. THE 12Z ECMWF IS THE PREFERRED MODEL
THROUGH TUESDAY AFTERNOON.

.ANALYSIS AND UPPER LEVELS...
A STRONG UPPER TROUGH OVER THE SOUTHWEST INTERIOR AND THE KENAI
PENINSULA IS SPREADING AREAS OF SNOW ACROSS THE THE KENAI PENINSULA,
SUSITNA VALLEY, MATANUSKA VALLEY AND ANCHORAGE. AREAS OF RAIN AND
SNOW FELL OVER PRINCE WILLIAM SOUND. ANOTHER SHORTWAVE TROUGH ALONG
THE KUSKOKWIM DELTA COAST HAD SPREAD SNOW SHOWERS INTO THE BETHEL
AREA. AN UPPER RIDGE IS BEGINNING TO DEVELOP OVER THE SOUTHEASTERN
BERING SEA. A BROAD SURFACE HIGH PRESSURE REMAINS OVER THE GULF OF
ALASKA AND LARGE MODERATE LOW HAS MOVED INTO THE WESTERN ALEUTIANS.

.SHORT TERM FORECAST...
THE UPPER TROUGH OVER WESTERN SOUTHCENTRAL ALASKA WILL MOVE INTO THE
COPPER RIVER BASIN TONIGHT AND INTO THE YUKON TERRITORY SUNDAY
AFTERNOON. UPPER RIDGE OVER THE SOUTHEAST BERING WILL AMPLIFY AS IT
MOVES THROUGH SOUTHWEST ALASKA TONIGHT AND INTO SOUTHCENTRAL ALASKA
AND THE GULF SUNDAY THEN BECOME NEARLY STATIONARY OVER EASTERN ALASKA
THROUGH TUESDAY. THE SURFACE LOW OVER THE WESTERN ALEUTIANS WILL
CONTINUE TO MOVE NORTH INTO THE NORTH BERING SUNDAY AND INTO THE
RUSSIA FAR EAST MONDAY. THE RIDGE OVER THE GULF WILL PERSIST THROUGH
MONDAY.

.SOUTHCENTRAL ALASKA...AREAS OF SNOW OVER WESTERN SOUTHCENTRAL WILL
MOVE EAST INTO THE COPPER RIVER BASIN TONIGHT WHERE IT WILL BECOME
SCATTERED SHOWERS SUNDAY MORNING. SKIES WILL BEGIN TO CLEAR FROM THE
WEST TONIGHT AND SPREAD TO REST OF THE AREA BY SUNDAY AFTERNOON.
MOSTLY SUNNY SKIES WILL CONTINUE PERSIST THROUGH MONDAY. THE WEAK
WEATHER FRONT WILL BRING SNOW TO KODIAK ISLAND SUNDAY NIGHT AND
MONDAY.

.SOUTHWEST ALASKA...SKIES WILL PARTIALLY CLEAR TONIGHT AS THE UPPER
RIDGE PASSES THROUGH THE AREA. MORE RAIN, SNOW AND GUSTY SOUTH WINDS
WILL MOVE INTO THE ALASKA PENINSULA, BRISTOL BAY AND THE KUSKOKWIM
DELTA SUNDAY AND SUNDAY NIGHT AS A WEATHER FRONT MOVES INTO THE AREA.

.BERING SEA AND ALEUTIANS...THE WEATHER FRONT OVER THE CENTRAL
ALEUTIANS WILL MOVE THROUGH THE EASTERN ALEUTIANS TONIGHT. RAIN AND
GUSTY SOUTH WINDS OVER THE CENTRAL AND EASTERN ALEUTIANS WITH BECOME
SNOW SHOWERS AND GUSTY WEST WINDS BEHIND THE FRONT SUNDAY THEN
DIMINISH SUNDAY NIGHT. ANOTHER STORM SYSTEM DEVELOPING OVER THE
NORTHWEST PACIFIC WILL BRING RAIN, SNOW AND GUSTY WINDS INTO THE
CENTRAL AND EASTERN ALEUTIANS MONDAY.

.LONG TERM FORECAST...
THE UPPER RIDGE OVER EASTERN ALASKA REMAIN THROUGH MIDWEEK AND KEEP
MOST OF THE WEATHER OUT OF SOUTHCENTRAL. THE WEATHER FRONT OVER
KODIAK ISLAND WILL DISSIPATE MONDAY NIGHT. THE STORM SOUTH OF THE
CENTRAL ALEUTIANS WILL TURN EAST TUESDAY THEN SOUTHEAST WEDNESDAY AND
WILL ONLY AFFECT THE ALASKA PENINSULA.

.AER/ALU...WATCH/WARNING SUMMARY
PUBLIC...HIGH WIND WATCH FOR THE ALASKA PENINSULA.
MARINE...GALE 150 170 172 175 176 185 179
         STORM 155 160 165 180
FIRE WEATHER...NONE.

NM APR 12