Blizzard Watch 11, NWS Anchorage, AK

439 
WWAK42 PAFC 030020
WSWALU

URGENT - WINTER WEATHER MESSAGE
NATIONAL WEATHER SERVICE ANCHORAGE AK
420 PM AKDT WED NOV 2 2011

AKZ155-031430-
/X.UPG.PAFC.BZ.A.0011.111103T0600Z-111104T0000Z/
/X.NEW.PAFC.BZ.W.0027.111103T0600Z-111104T0000Z/
KUSKOKWIM DELTA-
INCLUDING THE CITIES OF...BETHEL...HOOPER BAY...NUNIVAK ISLAND
420 PM AKDT WED NOV 2 2011

...BLIZZARD WARNING IN EFFECT FROM 10 PM THIS EVENING TO 4 PM
AKDT THURSDAY ALONG THE COAST...

THE NATIONAL WEATHER SERVICE IN ANCHORAGE HAS ISSUED A BLIZZARD
WARNING...WHICH IS IN EFFECT FROM 10 PM THIS EVENING TO 4 PM AKDT
THURSDAY. THE BLIZZARD WATCH IS NO LONGER IN EFFECT. 

* LOCATION...THE KUSKOKWIM DELTA COAST INCLUDING NUNIVAK ISLAND.

* SNOW...SNOW ACCUMULATION 4 TO 7 INCHES. SNOW BEGINS MIXING WITH
  RAIN DURING THE DAY FROM THE SOUTH.

* VISIBILITY...REDUCED TO LESS THAN ONE QUARTER MILE IN SNOW AND
  BLOWING SNOW.

* WIND...EAST TO SOUTHEAST WIND INCREASING TO 30 TO 40 MPH WITH
  GUSTS TO 50 MPH.

* TIMING...THE WORST CONDITIONS ARE EXPECTED AS SNOW AND STRONG
  WINDS BEGIN LATE THIS EVENING AND THROUGH THE DAY THURSDAY.

* IMPACTS...LOW VISIBILITY...STRONG WIND AND HEAVY SNOW WILL
  CREATE WHITEOUT CONDITIONS AND MAKE TRAVEL DANGEROUS.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A BLIZZARD WARNING MEANS SEVERE WINTER WEATHER CONDITIONS ARE
EXPECTED OR OCCURRING. FALLING AND BLOWING SNOW WITH STRONG WINDS
AND POOR VISIBILITIES ARE LIKELY. THIS WILL LEAD TO WHITE-OUT
CONDITIONS...MAKING TRAVEL EXTREMELY DANGEROUS. ALL TRAVEL AND
OUTDOOR ACTIVITY IS STRONGLY DISCOURAGED.

&&

$$

AKZ152-031430-
/X.NEW.PAFC.WW.Y.0021.111103T1300Z-111104T0300Z/
LOWER KUSKOKWIM VALLEY-
INCLUDING THE CITIES OF...ANIAK...SLEETMUTE
420 PM AKDT WED NOV 2 2011

...WINTER WEATHER ADVISORY IN EFFECT FROM 5 AM TO 7 PM AKDT
THURSDAY...

THE NATIONAL WEATHER SERVICE IN ANCHORAGE HAS ISSUED A WINTER
WEATHER ADVISORY FOR SNOW...WHICH IS IN EFFECT FROM 5 AM TO 7 PM
AKDT THURSDAY.

* LOCATION...THE LOWER KUSKOKWIM VALLEY...

* SNOW...STORM TOTAL SNOW ACCUMULATION OF 5 TO 9 INCHES...WITH
  ISOLATED POCKETS OF FREEZING RAIN...

* TIMING...SNOW WILL DEVELOP EARLY THURSDAY MORNING AND CONTINUE
  THROUGH THE AFTERNOON. PRECIPITATION INTENSITY WILL BEGIN TO WEAKEN
  THURSDAY EVENING...

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A WINTER WEATHER ADVISORY FOR SNOW MEANS THAT PERIODS OF SNOW WILL
CAUSE PRIMARILY TRAVEL DIFFICULTIES. BE PREPARED FOR SNOW COVERED
ROADS AND LIMITED VISIBILITIES...AND USE CAUTION WHILE DRIVING.

&&

$$

AKZ161-031430-
/X.NEW.PAFC.WW.Y.0021.111103T1300Z-111104T0000Z/
BRISTOL BAY-
INCLUDING THE CITIES OF...KING SALMON...DILLINGHAM...NAKNEK...
PILOT POINT
420 PM AKDT WED NOV 2 2011

...WINTER WEATHER ADVISORY IN EFFECT FROM 5 AM TO 4 PM AKDT
THURSDAY...

THE NATIONAL WEATHER SERVICE IN ANCHORAGE HAS ISSUED A WINTER
WEATHER ADVISORY FOR SNOW AND BLOWING SNOW...WHICH IS IN EFFECT
FROM 5 AM TO 4 PM AKDT THURSDAY.

* LOCATION...INLAND AREAS NORTH OF DILLINGHAM...

* SNOW...SNOW ACCUMULATION 4 TO 8 INCHES...

* VISIBILITY...OCCASIONALLY REDUCED TO ONE HALF MILE IN SNOW
  BLOWING SNOW.

* WIND...EAST WIND 25 TO 35 MPH...WITH GUSTS TO 45 MPH.

* TIMING...SNOW WILL DEVELOP ALONG THE WESTERN CAPES OVERNIGHT
  TONIGHT AND SPREAD EAST THROUGH THURSDAY. PRECIPITATION
  INTENSITY WILL WEAKEN BY LATE THURSDAY AFTERNOON...

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A WINTER WEATHER ADVISORY FOR SNOW AND BLOWING SNOW MEANS THAT
VISIBILITIES WILL BE LIMITED DUE TO A COMBINATION OF FALLING AND
BLOWING SNOW. USE CAUTION WHEN TRAVELING...ESPECIALLY IN OPEN
AREAS.

&&

$$

JAM

SOUTHCENTRAL AND SOUTHWEST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE ANCHORAGE AK
441 AM AKDT WED NOV 2 2011

.ANALYSIS AND UPPER LEVELS...

STACKED LOW PRESSURE SYSTEM IN THE GULF THAT HAS CAUSED QUITE THE
HEADACHE WITH OUR FORECASTS OVER SOUTHCENTRAL OVER THE PAST DAY OR SO
WILL CONTINUE MOVING SOUTHEAST THIS MORNING AND WILL ENTER THE
NORTHEAST PACIFIC AS IT WEAKENS LATER THIS MORNING. HIGH PRESSURE
RIDGING ALOFT MOVES OVER SOUTHCENTRAL TODAY AND PERSISTS THROUGH
TONIGHT AND WILL RESULT IN THE DEMISE OF STRONG WINDS IN MOST
LOCATIONS. IMMEDIATELY ON ITS HEELS IS A STORM FORCE LOW PRESSURE
SYSTEM. THE SURFACE REFLECTION...A 980 MB LOW ABOUT 350 MILES SOUTH
OF SHEMYA THIS MORNING...MOVES TO JUST SOUTH OF AMCHITKA THIS
AFTERNOON...THEN REDEVELOPS OVER THE CENTRAL BERING SEA THIS
AFTERNOON BEFORE MOVING INLAND OVER SOUTHWEST ALASKA BETWEEN ANIAK
AND CAPE NEWENHAM EARLY THURSDAY EVENING...WITH A SECONDARY LOW
FORMING OVER THE NORTHWESTERN GULF THURSDAY NIGHT INTO FRIDAY.

.MODEL DISCUSSION...

THERE ARE MINOR DISCREPANCIES BETWEEN THE MODELS IN HANDLING OF
PRINCIPAL WEATHER FEATURES OVER THE NEXT THREE DAYS...BUT NOTHING TOO
SIGNIFICANT THAT PRECLUDES USING ONE MODEL OVER THE OTHER. THE NAM
WAS PREFERRED FOR ITS DETAIL AND ITS SIMILARITIES WITH THE GLOBAL
MODELS. IN THE EXTENDED TIMEFRAME...LEANED HEAVILY ON HPC GUIDANCE AS
THERE IS CONSIDERABLE DIFFERENCES BETWEEN THE GFS AND EUROPEAN (EC)
GLOBAL FORECAST MODELS OVER THE BERING SEA BEYOND THREE DAYS.

.SHORT TERM FORECAST...

SOUTHCENTRAL ALASKA...

OUTFLOW WINDS OVER SOUTHCENTRAL ARE CURRENTLY IN A RELATIVE
LULL...BUT WILL AGAIN PICK UP LATER THIS MORNING THROUGH OUTFLOW GAPS
(SUCH AS PORTAGE PASS AND THOMPSON PASS) INTO PRINCE WILLIAM SOUND
AND THE NORTHERN GULF THROUGH THE AFTERNOON AS THE LAST IN A SERIES
OF UPPER LEVEL DISTURBANCES MOVES OVERHEAD ON THE BACK SIDE OF THE
LOW IN THE GULF. THIS SHOULD RESULT IN A CONTINUATION OF BLIZZARD
CONDITIONS THROUGH THOMPSON PASS INTO THE EVENING TONIGHT...WITH HIGH
WIND CONDITIONS CONTINUING THROUGH THIS AFTERNOON IN THE NORTHEAST
PRINCE WILLIAM SOUND REGION. OTHERWISE...UPPER LEVEL RIDGING MOVES
OVER THE REGION TONIGHT AND INTO THURSDAY MORNING BEFORE CLOUDS WITH
THE APPROACHING SYSTEM TO THE WEST STARTS TO MOVE INTO THE AREA. WITH
THE LOW APPROACHING FROM SOUTHWEST ALASKA...EXPECT STRONG SOUTHEAST
WINDS TO DEVELOP THROUGH TURNAGAIN ARM AND OVER HIGHER ELEVATIONS BY
THURSDAY AFTERNOON AND PERSIST THROUGH THURSDAY NIGHT.

SOUTHWEST ALASKA...

CLOUDS WILL INCREASE TODAY WITH SNOW DEVELOPING AND MOVING INLAND
TONIGHT. A STRONG WARM LOW LEVEL JET WILL ACCOMPANY THIS SYSTEM...AND
WILL EVENTUALLY ERODE THE EXISTING COLDER AIR NEAR THE SURFACE.
EXPECT ABOUT 6 HOURS OF LIGHT TO MODERATE SNOW ALONG THE IMMEDIATE
COASTLINE OF BRISTOL BAY...WITH A LONGER PERIOD OF SNOW FALLING
INLAND TOWARDS THE KUSKOKWIM VALLEY BEFORE THERE IS A CHANGEOVER...IF
ONE OCCURS AT ALL. ALSO EXPECTING TO SEE WINDS INCREASE ENOUGH TO
WARRANT MENTION OF BLOWING SNOW IN EXPOSED AREAS WHERE TEMPERATURES
REMAIN COLD ENOUGH.

BERING SEA/ALEUTIANS...

IT IS HARD NOT TO NOTICE SIMILARITIES BETWEEN THE SYSTEM AFFECTING
THE BERING THROUGH THE NEXT COUPLE OF DAYS AND THE POWERFUL SYSTEM
WHICH AFFECTED THE REGION BACK IN EARLY APRIL OF THIS YEAR. LOW
PRESSURE WILL BE TAKING A NEARLY IDENTICAL TRACK TO THE APRIL
STORM...THOUGH THIS TIME THE LOW'S CENTRAL PRESSURE WILL BE MUCH
HIGHER AND WILL ALSO NOT BE RAPIDLY DEEPENING WITH THIS STORM.
HOWEVER...A POWERFUL WEATHER FRONT WITH STORM FORCE SUSTAINED WINDS
AND HURRICANE FORCE GUSTS WILL MOVE EAST ACROSS THE CENTRAL AND
EASTERN BERING SEA TODAY AND TONIGHT. WITH 925 MB WINDS IN THE
NEIGHBORHOOD OF HURRICANE FORCE AND STRONG DOWNWARD OMEGA VALUES
SUPPORTING GOOD DOWNWARD MOTION ALONG AND NEAR THE FRONT...ESPECIALLY
IN HEAVIER PRECIPITATION...EXPECT WINDS TO EASILY REACH HIGH WIND
CRITERIA FOR THE EASTERN ALEUTIANS AND THE ALASKA PENINSULA. ALSO
EXPECT HURRICANE FORCE GUSTS OVER MARINE AREAS AS THE FRONT MOVES
THROUGH THE EASTERN BERING AND NEARBY COASTAL WATERS.

.LONG TERM FORECAST...

STORM SYSTEM IN THE GULF THURSDAY NIGHT WILL MOVE AWAY TOWARDS
SOUTHEAST ALASKA. THUS WILL LIKELY SEE A BRIEF ROUND OF LIGHT SNOW
FRIDAY AFTERNOON AND/OR FRIDAY NIGHT UNDER COLD ADVECTION REGIME OVER
NORTHERN COOK INLET REGION. NEXT SYSTEM APPROACHES FROM THE WEST FOR
THE WEEKEND. MODELS SEEM TO BE IN GOOD AGREEMENT IN STRETCHING THIS
SYSTEM EAST-WEST FROM BRISTOL BAY TO THE NORTHERN GULF...WITH SEVERAL
UPPER LEVEL DISTURBANCES MOVING THROUGH WITH COLD ADVECTION IN THE
LOW LEVELS OVER THE COOK INLET REGION. UNDER THESE CONDITIONS A
DECENT PERIOD OF SNOW BECOMES A DISTINCT POSSIBILITY FOR THE
ANCHORAGE AREA DURING SOME PART OF THE SATURDAY NIGHT THROUGH SUNDAY
NIGHT TIMEFRAME. WILL CONTINUE TO MONITOR MODEL TRENDS FOR NOW BEFORE
MAKING THE JUMP TO HIGHER PROBABILITIES FOR SNOW IN THE EXTENDEDS.

.AER/ALU...WATCH/WARNING SUMMARY
PUBLIC...HIGH WIND WATCH...181
         HIGH WIND WARNING...131 185
         BLIZZARD WARNING...131
MARINE...GALES...121 129 130 132 150 160
         STORMS...155 165 170 171 172 175 176 179 180 185
FIRE WEATHER...NONE.

29 NOV 11