Heavy Freezing Spray Warning 95, NWS Anchorage, AK

SOUTHCENTRAL AND SOUTHWEST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE ANCHORAGE AK
500 PM AKST TUE FEB 28 2012

.MODEL DISCUSSION...
THE MODELS ARE IN VERY GOOD AGREEMENT ON THE MAJOR SYNOPTIC SYSTEMS
THROUGH THURSDAY AFTERNOON. THE GFS AND ECMWF MODELS ARE PREFERRED
BECAUSE THEY DEVELOP A TRIPLE POINT LOW ALONG THE FRONT OVER THE
NORTHWESTERN GULF OF ALASKA THURSDAY AFTERNOON.

.ANALYSIS AND UPPER LEVELS...
A WEAK UPPER TROUGH EXTENDS ACROSS THE SOUTHWEST INTERIOR, KENAI
PENINSULA AND THE WESTERN GULF OF ALASKA. A WEAK UPPER RIDGE STILL
LIES ACROSS WESTERN CANADA. AN UPPER TROUGH MOVING NORTH THROUGH THE
WESTERN BERING SEA HAS WEAKENED THE RIDGE OVER THE CENTRAL BERING
SEA.

A WEAK SURFACE LOW SITS OVER THE NORTHEAST GULF OF ALASKA. A WEATHER
FRONT ACROSS THE CENTRAL BERING, THE PRIBILOF ISLANDS AND UNIMAK
ISLAND CONTINUES TO WEAKEN AS IT RUNS INTO THE RIDGE OVER THE
NORTHERN BERING. SCATTERED SNOW SHOWERS REMAIN OVER THE COASTAL
SECTIONS OF SOUTHCENTRAL ALASKA, THOUGH SKIES HAVE CLEARED OVER THE
COPPER RIVER BASIN. AREAS OF STRONG WINDS CONTINUED TO BLOW THROUGH
KODIAK ISLAND AND THE SOUTHERN COOK INLET. SOUTHWEST ALASKA WAS
MOSTLY CLEAR AND COLD TODAY.

.SHORT TERM FORECAST...
AN UPPER RIDGE OVER THE CENTRAL ALEUTIANS WILL BUILD INTO THE EASTERN
BERING SEA WEDNESDAY THEN MOVE THROUGH SOUTHWEST ALASKA AND INTO
SOUTHCENTRAL ALASKA AND THE GULF OF ALASKA LATE WEDNESDAY NIGHT AND
INTO SOUTHEAST ALASKA THURSDAY AFTERNOON. THE UPPER TROUGH OVER
SOUTHWEST ALASKA AND THE GULF WILL BE DISPLACED BY THE RIDGE THROUGH
SOUTHCENTRAL ALASKA TONIGHT AND WEDNESDAY.

.SOUTHCENTRAL ALASKA...THE WEAK LOW OVER THE NORTHERN GULF WILL
DISSIPATE WEDNESDAY NIGHT. GUSTY WINDS OVER KODIAK ISLAND WILL
DIMINISH THROUGH TONIGHT. SCATTERED SNOW SHOWERS WILL PERSIST OVER
THE AREA THROUGH WEDNESDAY AS THE UPPER TROUGH MOVES THROUGH
WEDNESDAY. A WEATHER FRONT WILL MOVE THE SOUTHWESTERN GULF WEDNESDAY
NIGHT THE SWING UP INTO THE NORTHERN GULF THURSDAY. SNOW AND GUSTY
WINDS ASSOCIATED WITH THE FRONT WILL MOVE INTO KODIAK ISLAND
WEDNESDAY NIGHT AND SPREAD ONTO THE CENTRAL GULF COAST AND THE KENAI
PENINSULA THURSDAY AFTERNOON.

,SOUTHWEST ALASKA...CLEAR AND COLD WEATHER WILL CONTINUE THROUGH
WEDNESDAY OVER THE SOUTHWEST MAINLAND. A WEATHER FRONT ASSOCIATED
WITH A LOW MOVING INTO THE CENTRAL ALEUTIANS WILL MOVE INTO THE
ALASKA PENINSULA WEDNESDAY NIGHT. SNOW AND GUSTY WINDS WILL MOVE INTO
THE ALASKA PENINSULA WEDNESDAY AFTERNOON AND SPREAD INTO BRISTOL BAY
AND THE SOUTHERN KUSKOKWIM DELTA WEDNESDAY NIGHT AND THURSDAY
MORNING. THE SNOW WILL BEGIN TO CHANGE TO SNOW SHOWERS IN THE
AFTERNOON.

.BERING SEA AND ALEUTIANS...THE WEATHER FRONT OVER THE CENTRAL BERING
AND EASTERN ALEUTIANS WILL DISSIPATE BY LATE AFTERNOON. A DEVELOPING
LOW OVER THE NORTH PACIFIC WILL STRENGTHEN RAPIDLY AS IT MOVES INTO
THE CENTRAL ALEUTIANS WEDNESDAY AFTERNOON THEN WILL MOVE EAST ALONG
THE ALEUTIANS INTO THE ALASKA PENINSULA THURSDAY AFTERNOON. RAIN,
SNOW AND GALE FORCE WINDS WILL MOVE INTO THE CENTRAL ALEUTIANS
TUESDAY NIGHT AND SPREAD TO THE EASTERN ALEUTIANS WEDNESDAY MORNING.
SNOW AND STRONG WINDS WITH POSSIBLE BLIZZARD CONDITIONS WILL MOVE
INTO THE PRIBILOFS WEDNESDAY EVENING THROUGH EARLY THURSDAY MORNING.

.LONG TERM FORECAST...
THE LOW OVER THE ALASKA PENINSULA THURSDAY EVENING WILL MOVE INTO THE
GULF OF ALASKA FRIDAY MORNING AND REMAIN THERE THROUGH THE WEEKEND.

.AER/ALU...WATCH/WARNING SUMMARY
PUBLIC...BLIZZARD WATCH FOR THE PRIBILOFS.
MARINE...GALE 130 132 150 155 160 165 171 179 180 185
         STORM 170 172 175
FIRE WEATHER...NONE.

NM FEB 12