Gale Warning 1096, NWS Anchorage, AK

SOUTHCENTRAL AND SOUTHWEST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE ANCHORAGE AK
500 PM AKST WED DEC 29 2010

.MODEL DISCUSSION...
THE MODELS ARE IN MUCH BETTER AGREEMENT THIS MORNING THROUGH THURSDAY
NIGHT. THE EUROPEAN MODEL SEEMS TO BE THE MOST CONSISTENT SOLUTION OF
ALL THE MODELS AND IS PREFERRED THROUGH FRIDAY NIGHT.

.ANALYSIS AND UPPER LEVELS...
.UPPER LEVELS...AN UPPER LOW OVER NORTHWEST ALASKA CONTINUES TO MOVE
SOUTHWEST TOWARD THE BERING SEA. A SHORT-WAVE TROUGH OVER THE KENAI
PENINSULA AND PRINCE WILLIAM SOUND HAD PRODUCED AREA OF SNOW OVER
SOUTHCENTRAL ALASKA TODAY. THE UPPER RIDGE OVER THE GULF OF ALASKA
AND NORTHEAST PACIFIC IS SLOWLY DRIFTING TO THE EAST.
.AT THE SURFACE...A STRONG 972 MB LOW JUST SOUTH OF THE CENTRAL
ALEUTIANS CONTINUES TO MOVE EAST. IT ASSOCIATED OCCLUDED FRONT
EXTENDS ACROSS THE SOUTHEASTERN BERING TO BRISTOL BAY WHERE IT MEETS
THE COLD FRONT EXTENDING SOUTHWARD AND A WARM FRONT EXTENDING
EASTWARD ACROSS KODIAK ISLAND AND INTO THE CENTRAL GULF. AREAS OF
SNOW OVER BRISTOL BAY AND KODIAK ISLAND WILL MOVE NORTHWARD INTO
SOUTHWEST ALASKA AND THE CENTRAL GULF COAST TONIGHT.

.SHORT TERM FORECAST...
A SIGNIFICANT CHANGE IN THE PATTERN IS OCCURRING. THE UPPER LOW OVER
NORTHWEST ALASKA WILL MOVE SOUTHWEST AND BECOME NEARLY STATIONARY
OVER THE BERING SEA FRIDAY. THE RIDGE OVER THE NORTHEAST PACIFIC WILL
MOVE INTO THE WESTERN CANADA BY THE END OF THE WEEK. THIS SHIFT IN
THE PATTERN WILL PUT THE SOUTHERN MAINLAND INTO A WARM, MOIST FLOW
FROM THE SOUTH AND SOUTHWEST. TEMPERATURES ARE EXPECTED TO RISE TO
NEAR OR SLIGHTLY ABOVE NORMAL OVER THE NEXT TWO DAYS. AN INCREASE IN
PRECIPITATION IS ALSO EXPECTED OVER THE NEXT FEW DAYS.

.SOUTHCENTRAL ALASKA...THE WARM FRONT OVER THE GULF WILL MOVE INTO
THE CENTRAL GULF COAST LATE TONIGHT AND EARLY THURSDAY MORNING. A LOW
WILL DEVELOP SOUTH OF KODIAK ISLAND THURSDAY MORNING AND MOVE INTO
THE INTERIOR FRIDAY AFTERNOON. AREAS OF SNOW WILL MOVE ONTO THE
CENTRAL GULF COAST AND EASTERN KENAI PENINSULA TONIGHT AND SPREAD
INTO THE SOUTHCENTRAL INTERIOR THURSDAY. GUSTY SOUTHEAST WINDS
DEVELOPING ALONG TURNAGAIN ARM COMBINED WITH THE SNOW COULD POSSIBLY
PRODUCE BLIZZARD CONDITIONS OVER THE EAST END OF THE ARM TONIGHT
THROUGH THURSDAY AFTERNOON. SOME OF THE SNOW OVER THE SOUTHERN PRINCE
WILLIAM SOUND AND EASTERN KENAI PENINSULA COULD CHANGE TO RAIN AND
POSSIBLE AREAS OF FREEZING RAIN THURSDAY AFTERNOON AND EVENING.
IMPROVING CONDITIONS WILL MOVE INTO REGION FROM THE WEST WITH AN
UPPER RIDGE FRIDAY.

.SOUTHWEST ALASKA...THE FRONT OVER BRISTOL BAY WILL WEAKEN AS IT
MOVES INTO SOUTHWEST ALASKA TONIGHT THEN DISSIPATE THURSDAY. AREAS OF
SNOW WILL MOVE INTO THE SOUTHWEST MAINLAND TONIGHT THEN BECOME SNOW
SHOWERS WEST OF DILLINGHAM THURSDAY. THE LOW DEVELOPING SOUTH OF
KODIAK THURSDAY MORNING WILL KEEP AREAS OF SNOW OVER EASTERN BRISTOL
BAY ZONE AND THE LOWER KUSKOKWIM VALLEY THROUGH THURSDAY NIGHT.
IMPROVING CONDITIONS WILL MOVE INTO REGION FROM THE SOUTHWEST WITH AN
UPPER RIDGE FROM FRIDAY MORNING.

.BERING SEA...THE LOW PRESSURE SYSTEM SOUTH OF THE CENTRAL ALEUTIANS
WILL MOVE EAST AND DISSIPATE SOUTH OF THE EASTERN ALEUTIANS THURSDAY.

ANOTHER LOW OVER THE NORTHWEST PACIFIC WILL MOVE EAST, JUST SOUTH OF
THE ALEUTIANS, THROUGH FRIDAY AFTERNOON. NORTHEAST FLOW OVER THE
BERING SEA WILL PERSIST THROUGH FRIDAY. SNOW SHOWERS WILL CONTINUE
OVER THE BERING SEA AND WESTERN ALEUTIANS THROUGH FRIDAY. SCATTERED
RAIN SHOWERS OVER THE EASTERN ALEUTIANS AND THE ALASKA PENINSULA WILL
CHANGE TO MIXED RAIN AND SHOWERS SHOWERS THURSDAY NIGHT AND FRIDAY.

.LONG TERM FORECAST...
CURRENT LONG TERM MODELS ARE IN FAIR AGREEMENT ON THE MOVEMENT OF THE
MAJOR SYSTEMS. THE SURFACE LOW SOUTH OF THE EASTERN ALEUTIANS LATE
FRIDAY WILL TURN NORTH INTO THE SOUTHEAST BERING AND BRISTOL BAY
SATURDAY AND CONTINUE TO MOVE NORTH INTO THE SEWARD PENINSULA SUNDAY.
THIS WILL REINFORCE THE MOIST SOUTHERLY FLOW OVER SOUTHCENTRAL ALASKA
AND THE EASTERN SECTIONS OF SOUTHWEST ALASKA THROUGH THE WEEKEND.
SNOW, ESPECIALLY ALONG THE GULF COAST WILL PERSIST THROUGH THE
WEEKEND.

.AER/ALU...WATCH/WARNING SUMMARY
PUBLIC...BLIZZARD WARNING FOR THE PRIBILOFS. BLIZZARD WATCH FOR
EASTERN KENAI PENINSULA.
MARINE...GALE 120 125 130 140 172 175 179 180 185
FIRE WEATHER...NONE.

NM DEC 10