Blizzard and Coastal Flood in Alaska, November 11 to 12, 2011

SOUTHCENTRAL AND SOUTHWEST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE ANCHORAGE AK
500 AM AKST FRI NOV 11 2011

.MODEL DISCUSSION...
MODELS DID A GOOD JOB OF INITIALIZING IN BOTH THE EAST AND WEST. THEY
ARE HANDLING THE NEXT WESTERN LOW MAKING LANDFALL NEAR BETHEL THIS
MORNING ALONG WITH THE TRIPLE POINT LOW DEVELOPING JUST TO THE EAST
OF KODIAK BY THIS EVENING. MODEL PREFERENCE TRENDED TOWARD THE NAM
MAINLY FOR THE DETAIL IN THE EAST. BY SUNDAY ALL MODELS SHOW A ZONAL
FLOW OVER THE GULF AND THE BERING.

.ANALYSIS AND UPPER LEVELS...
THE RIDGE OF HIGH PRESSURE WHICH BROUGHT CLEAR SKIES TO MOST OF
SOUTHCENTRAL OVERNIGHT HAS PUSHED OFF TO THE EAST OVER THE ALCAN
BOARDER THIS MORNING. A DEEP 965 MB LOW MOVING OVER SAINT PAUL ISLAND
WILL CONTINUE TO INTENSIFY AND MAKE LANDFALL BY THIS EVENING OVER THE
KUSKOKWIM DELTA AT 955 MB. THE ASSOCIATED FRONT IS EXPECTED TO PUSH
UP AGAINST THE WEST COAST BY LATE MORNING. A 974 MB TRIPLE POINT LOW
WILL DEVELOP JUST TO THE EAST OF KODIAK CITY THIS EVENING...IT WILL
THEN DRIFT EASTWARD MAKING LANDFALL NEAR YAKUTAT SATURDAY MORNING.

.SHORT TERM FORECAST...
SOUTHCENTRAL...
PRECIPITATION BEGIN OVER KODIAK THIS MORNING AS RAIN AND SNOW
SPREADING TO THE NORTHEAST AS SNOW AS IT MOVES UP THE KENAI PENINSULA
AND EAST INTO THE COASTAL AREAS OF PRINCE WILLIAMS SOUND. THE 700 MB
FLOW OVER ANCHORAGE BOWL IS NOW MORE TO FROM THE SOUTH TO SOUTHEAST
TODAY SO SNOW SHOULD START OUT FAIRLY LIGHT OVER THE CITY WITH LITTLE
ACCUMULATION THIS AFTERNOON...SNOW WILL CONTINUE THROUGH SATURDAY
MORNING BEFORE TAPERING OFF TO SCATTERED SNOW SHOWERS IN THE
AFTERNOON FOR ANCHORAGE. SNOW WILL ALSO SPREAD NORTH OVER THE
MATANUSKA AND SUSITNA VALLEYS AND THE COPPER RIVER BASIN BY TONIGHT
THROUGH SATURDAY MORNING.

SOUTHWEST...
ALONG THE KUSKOKWIM DELTA BLIZZARD CONDITIONS ARE EXPECTED TO BEGIN
THIS MORNING AHEAD OF THE APPROACHING FRONT AND CONTINUE THROUGH
FRIDAY NIGHT. AN ADVISORY IS ALSO IN EFFECT FOR SNOW...BLOWING SNOW
AND FREEZING RAIN ACROSS THE BRISTOL BAY ZONE FOR THIS MORNING
THROUGH LATE TONIGHT. ALSO ALONG WITH STRONG WESTERLY WINDS AND A
LONG FETCH OVER THE BERING SEA...A FLOOD WARNINGS ARE EXPECTED ALONG
THE WEST COAST FROM GOODNEWS BAY NORTHWARD FROM THIS EVENING INTO
SATURDAY.

ALASKA PENINSULA/BERING...
A STRONG WESTERLY FLOW WILL SET UP OVER MUCH OF THE BERING AND ALASKA
PENINSULA BY THIS EVENING WITH STORM FORCE WIND OVER MUCH OF THE
EASTERN HALF OF THE BERING AND GALES OVER THE THE REST. AREAS OF RAIN
OR RAIN AND SNOW TO THE NORTH WILL CHANGE OVER TO SNOW SHOWERS OVER
BY SATURDAY.

.LONG TERM FORECAST...
A LONG WAVE TROF OVER THE CENTRAL BERING DRIFTS EASTWARD AND FLATTENS
OUT AS IT PASSES OVER THE MAINLAND SETTING UP A ZONAL FLOW OVER GULF
THROUGH THE WEEKEND. A RIDGE OF HIGH PRESSURE WILL BEGIN BUILDING
OVER THE CENTRAL BERING BY MONDAY NIGHT WHILE A TROF DEEPENS OVER THE
MAINLAND BY TUESDAY. THIS WILL ALLOW COLD DRY AIR TO DROP DOWN OVER
MUCH OF THE EASTERN DOMAIN BY MIDWEEK.

.AER/ALU...WATCH/WARNING SUMMARY
PUBLIC...BLIZZARD WARNING...125 155.
         WINTER WEATHER ADVISORY...121 145 161.
         COASTAL FLOOD WARNING...155 161.
MARINE...HURRIACNE FORCE...180.
         STORMS...120 130 132 138 150 155 160 165 170 179 185.
         GALES...140 141 171 172 175 176.
FIRE WEATHER...NONE.

NOV 11