Gale Warning 717, NWS Anchorage, AK

SOUTHCENTRAL AND SOUTHWEST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE ANCHORAGE AK
500 AM AKDT THU OCT 6 2011

.MODEL DISCUSSION...
MODELS IN FAIRLY GOOD AGREEMENT IN THE SHORT TERM...WITH SOME TIMING
DIFFERENCES IN A LOW FORECAST TO MOVE EASTWARD SOUTH OF THE
ALEUTIANS FRIDAY AND SATURDAY. THE NAM WAS THE PREFERRED MODEL WITH
ITS BETTER HANDLING OF SMALL DETAILS AND ITS "COMPROMISE" POSITION
ON THE ABOVE MENTIONED LOW BETWEEN THE GFS AND ECMWF.

MODELS NOT IN VERY GOOD AGREEMENT FOR THE EXTENDED PORTION OF THE
FORECAST. PREFERENCE FOR THE ECMWF WITH ITS BETTER CONTINUITY...AND
THE HPC FORECAST.

.ANALYSIS AND UPPER LEVELS...
THERE IS AN UPPER LEVEL LOW OVER SOUTHWEST ALASKA THIS MORNING WITH
RIDGING TO THE EAST OVER NORTHWEST CANADA AND WEAK RIDGING OVER THE
WESTERN BERING SEA. A FRONT ASSOCIATED WITH THE LOW IS CURRENTLY
ALONG THE NORTH GULF COAST. THERE ARE TWO SURFACE LOWS ASSOCIATED
WITH THIS UPPER LOW...ONE CENTERED NEAR TOGIAK AND THE OTHER NEAR
THE SOUTHWEST TIP OF KODIAK ISLAND.

.SHORT TERM FORECAST...
THE SOUTHWEST ALASKA UPPER LOW WILL VERY SLOWLY DRIFT EAST FOR THE
NEXT FEW DAYS AND BE CENTERED JUST SOUTH OF SEWARD BY SATURDAY
AFTERNOON. THE LOW WILL ALSO GRADUALLY WEAKEN THROUGH SATURDAY.
STILL PLENTY OF PRECIPITATION EXPECTED TODAY AND TONIGHT ALONG THE
GULF COAST...MAINLY EAST OF SEWARD. SHOWERS CONDITIONS EXPECTED
INLAND. SHOWER ACTIVITY WILL DECREASE ON FRIDAY AND SATURDAY AS THE
UPPER LOW MOVES OVER SOUTH CENTRAL ALASKA AND THE FLOW BECOMES WEAK.

PRECIPITATION AND WINDS FROM A RAPIDLY DEVELOPING CYCLONE SOUTH OF
THE WESTERN ALEUTIANS ON FRIDAY WILL MOVE INTO THE CENTRAL ALEUTIANS
FRIDAY NIGHT AND INTO THE EASTERN ALEUTIANS AND POSSIBLY THE ALASKA
PENINSULA SATURDAY. THE LOW ITSELF WILL STAY SOUTH OF THE THE
ALEUTIANS AND IN FACT WILL TRACK ALMOST DUE EAST ALONG 50 DEGREES
NORTH LATITUDE.

.LONG TERM FORECAST...
ALTHOUGH THE EXTENDED GUIDANCE IS NOT IN GREAT AGREEMENT IT LOOKS
LIKE THE SOUTHERN ALASKA MAINLAND WILL BE MAINLY DRY FOR THE EARLY
PORTIONS OF NEXT WEEK. BY THE MIDDLE OF THE WEEK THERE IS THE
POSSIBILITY THAT THE UPPER LEVEL WESTERLIES WILL OPEN UP THROUGH THE
BERING SEA AND BRING BETTER CHANCES OF PRECIPITATION TO THE AREA.

.AER/ALU...WATCH/WARNING SUMMARY
PUBLIC...NONE.
MARINE...GALE WARNING 125.
FIRE WEATHER...NONE.

LUDWIG OCT 11