Gale Warning 425, NWS Anchorage, AK

AREA FORECAST DISCUSSION
SOUTHCENTRAL AND SOUTHWEST ALASKA
400 PM AKDT WED MAY 19 2010

.MODEL DISCUSSION...MODELS SEEM TO BE DOING WELL WITH THE MAJOR
FEATURES AND HAVE LOCKED ON THE THE EASTERLY WAVE MOVING INTO THE
SOUTH CENTRAL REGION THIS AFTERNOON. THE BIGGEST DISAGREEMENT IS WITH
THE COMPLEX LOW THAT WILL BE SOUTH OF KODIAK ISLAND THURSDAY. THE GFS
WANTS TO CONSOLIDATE THE ENERGY INTO ONE LOW BUT THE NAM ECMWF AND
UKMET ALL WANT TO HAVE MULTIPLE WEAK CENTERS. EVEN THOUGH THE MODELS
DO NOT COMPLETELY AGREE ON THE EXACT LOCATIONS OF THE CENTERS THE
TROUGH AXIS IS IN THE SAME PLACE ON ALL OF THEM AND THAT IS WHAT IS
MORE IMPORTANT TO THE FORECAST.

.ANALYSIS AND UPPER LEVELS...THE OVERALL WEATHER PATTERN HAS AN UPPER
LEVEL RIDGE OVER WESTERN CANADA THAT EXTENDS INTO THE INTERIOR PART
OF THE STATE. THE DOMINANT UPPER LEVEL LONG WAVE LOW IS SOUTH OF THE
GULF OF ALASKA WITH A PRONOUNCED TROUGH EXTENDING TO THE NORTHWEST
AND INTO EASTERN RUSSIA. THIS UPPER TROUGH WILL REMAIN IN NEARLY THE
POSITION OVER THE NEXT DAY BUT WILL DEVELOP THREE DISTINCT CENTERS
WITH ONE DEVELOPING OVER THE BERING SEA AND THE ONE CURRENTLY OVER
THE GULF MOVING OFF THE COAST OF VANCOUVER ISLAND WHILE LEAVING A
WEAK THIRD CENTER NEAR KODIAK ISLAND.
ONTO SMALLER SCALE FEATURES...THERE IS A SHARP UPPER LEVEL
DISTURBANCE MOVING FROM EAST TO WEST OVER THE NORTH GULF COAST INTO
SOUTH CENTRAL ALASKA THIS AFTERNOON AND EVENING. THIS EASTERLY WAVE
WILL MOVE WEST IF THE ALASKA RANGE AROUND MIDNIGHT...THOUGH IT SHOULD
BE WEAKENING AS IT MOVES WESTWARD.

.SHORT TERM FORECAST...
RAIN WILL ACCOMPANY THE EASTERLY WAVE THIS AFTERNOON AND OVERNIGHT.
WINDS WILL BE STRONGEST AROUND THIS SYSTEM ALONG THE NORTH GULF COAST
AND NORTHERN KODIAK ISLAND WATERS TONIGHT...AND THEN WINDS SHOULD
RAPIDLY DECREASE IN THOSE AREA.
THE BEST CHANCE OF LATE AFTERNOON AND EVENING THUNDERSTORMS IS IN THE
UPPER KUSKOKWIM VALLEY WITH A LESSER CHANCE IN THE KUSKOKWIM DELTA.
THE ATMOSPHERIC CAP IN THE KUSKOKWIM DELTA WAS QUITE STRONG TODAY
WITH FOG IN NUMEROUS LOCATION IN AND NEAR BETHEL UNTIL NOON.
NOT MUCH CHANGE IN THE BERING SEA REGION AS NORTHWEST FLOW AND
STRATUS WILL CONTINUE OVER THAT AREA.

.LONG TERM FORECAST...AN UPPER LEVEL RIDGE WILL SOLIDIFY OVER THE
NORTHERN AND INTERIOR PART OF THE STATE WITH THE COLD UPPER LEVEL
TROUGH WILL PERSIST OVER THE ALASKA PENINSULA AND CENTRAL BERING SEA.

CONVECTION WILL PERSIST IN INLAND AREAS AS A THERMAL TROUGH WILL ALSO
BE IN PLAY IN THE INTERIOR THROUGH THE WEEKEND.

.AER/ALU...WATCH/WARNING SUMMARY
PUBLIC...NONE.
MARINE...GALE 120 130.
FIRE WEATHER...NONE.

MAY 10