Heavy Freezing Spray Warning 149, NWS Anchorage, AK

SOUTHCENTRAL AND SOUTHWEST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE ANCHORAGE AK
517 PM AKST SUN NOV 20 2011

.ANALYSIS AND UPPER LEVELS...
THE MAJOR STORM SYSTEM OVER THE BERING SEA SATURDAY MOVED ACROSS THE
EASTERN ALEUTIANS THIS MORNING AND IS MOVING INTO THE NORTH PACIFIC.
THE DEVELOPING LOW SOUTH OF KODIAK ISLAND YESTERDAY EVENING HAS
STRENGTHEN AS IT DRIFTED INTO THE SOUTHWEST GULF THIS AFTERNOON.
ANOTHER HAS DEVELOPED JUST SOUTH OF THE EASTERN GULF AND IS MOVING
NORTH.

UPPER LEVELS...AN UPPER LOW OVER THE SOUTHWEST GULF IS VERTICALLY
STACKED ABOVE THE SURFACE LOW. ANOTHER LOW SIT OVER THE BEAUFORT SEA
WITH A TROUGH EXTENDING SOUTH IN THE THE CENTRAL INTERIOR. AN UPPER
RIDGE IS BEGINNING TO BUILD OVER THE WESTERN BERING.

.MODEL DISCUSSION...
THE MODEL HAVE COME INTO GOOD AGREEMENT ESPECIALLY OVER THE GULF. THE
NAM MODEL WAS PREFERRED OVER THE GULF BECAUSE IT HANDLES THE COASTAL
WINDS THE BEST AND THE GFS WAS USED ELSE WHERE.

.SHORT TERM FORECAST...
THE LOW OVER THE SOUTHWEST GULF WILL MOVE SOUTHEAST AND DISSIPATE
JUST SOUTH OF THE CENTRAL GULF MONDAY EVENING. THE LOW ENTERING THE
EASTERN GULF WILL MOVE TO NEAR MIDDLETON ISLAND MONDAY AFTERNOON THEN
DRIFT WEST TO BE JUST SOUTH OF THE KENAI PENINSULA TUESDAY. A RIDGE
DEVELOPING OVER THE WESTERN BERING SEA WILL MOVE INTO THE CENTRAL
BERING MONDAY AND INTO THE EASTERN BERING TUESDAY.

.SOUTHCENTRAL ALASKA AND THE GULF...SNOW OVER KODIAK ISLAND WILL
DIMINISH TO SNOW SHOWERS TONIGHT AS THE LOW MOVES AWAY AND WINDS
BECOME NORTHWESTERLY BY MONDAY AFTERNOON. AREAS OF SNOW ALONG THE
CENTRAL GULF COAST AND PRINCE WILLIAM SOUND WILL MOVE INTO THE KENAI
PENINSULA, ANCHORAGE AND AND THE MATANUSKA VALLEY TONIGHT THEN BECOME
SNOW SHOWER MONDAY. MORE SNOW WILL MOVE BACK INTO SOUTHCENTRAL ALASKA
MONDAY NIGHT AND TUESDAY. GUSTY WINDS AND LOW WIND CHILL TEMPERATURES
WILL PERSIST NEAR THOMPSON PASS INTO MONDAY.

SOUTHWEST ALASKA...BRISK NORTH TO NORTHEAST WINDS WILL PERSIST AND
WILL BRING COLD DRY AIR BACK INTO THE REGION THROUGH TUESDAY. SKIES
WILL CLEAR FROM THE NORTH TONIGHT AND WILL REMAIN CLEAR THROUGH
MONDAY NIGHT. SOME CLOUDS OVER SOUTHCENTRAL ALASKA WILL MOVE INTO THE
LOWER KUSKOKWIM VALLEY AND EASTERN BRISTOL BAY TUESDAY. THE COLD
TEMPERATURE AND BRISK WINDS WILL PRODUCE AREAS OF VERY LOW WIND CHILL
TEMPERATURES DOWN TO 35 BELOW ZERO MAINLY OVER THE DELTA.

BERING SEA AND THE ALEUTIANS...GUSTY NORTH TO NORTHWEST WINDS OVER
THE EASTERN BERING WILL DIMINISH THROUGH MONDAY AS THE RIDGE MOVES
INTO THE CENTRAL BERING. A LOW OVER WEST OF THE KAMCHATKA PENINSULA
WILL MOVE INTO THE WESTERN BERING TUESDAY. THE ASSOCIATED WEATHER
FRONT EXTENDING SOUTH OVER THE NORTHWEST PACIFIC WILL SWING NORTH
INTO THE WESTERN ALEUTIANS MONDAY AND INTO THE CENTRAL BERING AND
EASTERN ALEUTIANS TUESDAY. RAIN AND SNOW ASSOCIATED WITH THE FRONT
WILL MOVE INTO THE WESTERN ALEUTIANS MONDAY AND SPREAD THROUGH THE
REST OF THE CHAIN BY TUESDAY.

.LONG TERM FORECAST...
THE MID-RANGE MODEL REMAIN IN GENERALLY GOOD AGREEMENT. THE LOW IN
THE NORTHWESTERN GULF TUESDAY NIGHT WILL MEANDER AROUND THE GULF
THROUGH FRIDAY. AREAS OF SNOW SHOWERS WILL REMAIN OVER THE GULF AND
ADJACENT COASTAL AREAS THROUGH THE REST OF THE WEEK. SOUTHWEST ALASKA
WILL REMAIN MOSTLY CLEAR AND COLD AS THE NORTHEASTERLY FLOW CONTINUES
BUT WEAKEN THROUGH THE LATTER HALF OF THE WEEK. MOSTLY CLOUDY SKIES
AND SNOW SHOWERS WILL PERSIST ALONG THE ALEUTIANS AS THE LOW OVER THE
WESTERN BERING DROPS OVER THE WESTERN ALEUTIANS WEDNESDAY THEN MOVES
ALONG THE CHAIN THROUGH THURSDAY NIGHT.

.AER/ALU...WATCH/WARNING SUMMARY
PUBLIC...BLIZZARD WATCH 125 131.
MARINE...GALE WARNING...120 128 129 138 155 160 165 180.
         STORM WARNING...127 130 132 150.
         HEAVY FREEZING SPRAY...121 126 127 128 129 130 132 138 140
                                141 150 160 180.
FIRE WEATHER...NONE.

NM NOV 11