Winter Weather Advisory 21, NWS Anchorage, AK

931 
WWAK42 PAFC 031301
WSWALU

URGENT - WINTER WEATHER MESSAGE
NATIONAL WEATHER SERVICE ANCHORAGE AK
501 AM AKDT THU NOV 3 2011

...STRONG LOW PRESSURE SYSTEM IN THE CENTRAL BERING SEA CONTINUING
TO IMPACT SOUTHWEST ALASKA WITH STRONG WINDS AND WINTER CONDITIONS...

AKZ155-040000-
/X.CON.PAFC.BZ.W.0027.000000T0000Z-111104T0000Z/
KUSKOKWIM DELTA-
INCLUDING THE CITIES OF...BETHEL...HOOPER BAY...NUNIVAK ISLAND
501 AM AKDT THU NOV 3 2011

...BLIZZARD WARNING REMAINS IN EFFECT UNTIL 4 PM AKDT THIS
AFTERNOON ALONG THE NORTHERN COAST...

A BLIZZARD WARNING REMAINS IN EFFECT UNTIL 4 PM AKDT THIS
AFTERNOON. 

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

* SNOW...SNOW ACCUMULATION 2 TO 4 INCHES. SNOW WILL BEGIN 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 40 TO 50 MPH DECREASING TO 20 TO
  35 MPH IN THE LATE AFTERNOON.

* TIMING...THE WORST CONDITIONS ARE EXPECTED THROUGH THE MORNINGS
  HOURS BEFORE GRADUALLY IMPROVING AS TEMPERATURES WARM THIS
  AFTERNOON.

* 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.

&&

$$

AKZ152-040300-
/X.CON.PAFC.WW.Y.0021.000000T0000Z-111104T0300Z/
LOWER KUSKOKWIM VALLEY-
INCLUDING THE CITIES OF...ANIAK...SLEETMUTE
501 AM AKDT THU NOV 3 2011

...WINTER WEATHER ADVISORY FOR SNOW REMAINS IN EFFECT UNTIL 7 PM
AKDT THIS EVENING...

A WINTER WEATHER ADVISORY REMAINS IN EFFECT UNTIL 7 PM AKDT THIS
EVENING. 

* LOCATION...THE LOWER KUSKOKWIM VALLEY.

* SNOW...STORM TOTAL SNOW ACCUMULATION OF 5 TO 8 INCHES.

* TIMING...SNOW WILL SPREAD FROM WEST TO EAST THIS MORNING AND
  BECOME HEAVY AT TIMES BY MIDDAY. THE INTENSITY OF THE SNOWFALL
  WILL BEGIN TO DIMINISH EARLY THIS 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.

&&

$$

AKZ161-040000-
/X.CON.PAFC.WW.Y.0021.000000T0000Z-111104T0000Z/
BRISTOL BAY-
INCLUDING THE CITIES OF...KING SALMON...DILLINGHAM...NAKNEK...
PILOT POINT
501 AM AKDT THU NOV 3 2011

...WINTER WEATHER ADVISORY FOR SNOW AND BLOWING SNOW REMAINS IN
EFFECT UNTIL 4 PM AKDT THIS AFTERNOON...

A WINTER WEATHER ADVISORY REMAINS IN EFFECT UNTIL 4 PM AKDT THIS
AFTERNOON. 

* 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 20 TO 35 MPH...WITH LOCAL GUSTS TO 45 MPH.

* TIMING...SNOW WILL SPREAD RAPIDLY FROM WEST TO EAST THIS
  MORNING. THE HEAVIEST SNOW WILL FALL THROUGH EARLY THIS
  AFTERNOON BEFORE TEMPERATURES WARM TO NEAR FREEZING AND THE SNOW
  BEGINS TO MIX WITH RAIN.

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.

&&

$$

503 
WWAK42 PAFC 040005
WSWALU

URGENT - WINTER WEATHER MESSAGE
NATIONAL WEATHER SERVICE ANCHORAGE AK
405 PM AKDT THU NOV 3 2011

...STRONG LOW PRESSURE SYSTEM IN THE CENTRAL BERING SEA
CONTINUING TO IMPACT SOUTHWEST ALASKA WITH STRONG WINDS AND
WINTER CONDITIONS...

AKZ155-040115-
/X.CAN.PAFC.BZ.W.0027.000000T0000Z-111104T0000Z/
KUSKOKWIM DELTA-
INCLUDING THE CITIES OF...BETHEL...HOOPER BAY...NUNIVAK ISLAND
405 PM AKDT THU NOV 3 2011

...BLIZZARD WARNING HAS EXPIRED...

TEMPERATURES HAVE WARMED ACROSS THE REGION AND MOSTLY RAIN IS NOW
FALLING. PRECIPITATION WILL ALSO DIMINISH THIS EVENING AS THE LOW
PRESSURE SYSTEM PROGRESSES EASTWARD.


$$

AKZ161-040115-
/X.CAN.PAFC.WW.Y.0021.000000T0000Z-111104T0000Z/
BRISTOL BAY-
INCLUDING THE CITIES OF...KING SALMON...DILLINGHAM...NAKNEK...
PILOT POINT
405 PM AKDT THU NOV 3 2011

...WINTER WEATHER ADVISORY HAS EXPIRED...

TEMPERATURES HAVE WARMED ACROSS THE REGION AND MOSTLY RAIN IS NOW
FALLING. PRECIPITATION WILL ALSO DIMINISH THIS EVENING AS THE LOW
PRESSURE SYSTEM PROGRESSES EASTWARD.

$$

AKZ152-040300-
/X.CON.PAFC.WW.Y.0021.000000T0000Z-111104T0300Z/
LOWER KUSKOKWIM VALLEY-
INCLUDING THE CITIES OF...ANIAK...SLEETMUTE
405 PM AKDT THU NOV 3 2011

...WINTER WEATHER ADVISORY REMAINS IN EFFECT UNTIL 7 PM AKDT THIS
EVENING...

A WINTER WEATHER ADVISORY REMAINS IN EFFECT UNTIL 7 PM AKDT THIS
EVENING. 

* LOCATION...THE LOWER KUSKOKWIM VALLEY.

* SNOW...STORM TOTAL SNOW ACCUMULATION OF 5 TO 8 INCHES.

* TIMING...SNOW WILL SPREAD FROM WEST TO EAST THIS MORNING AND 
  BECOME HEAVY AT TIMES BY MIDDAY. THE INTENSITY OF THE SNOWFALL 
  WILL BEGIN TO DIMINISH EARLY THIS 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.

&&

$$

869 
WWAK42 PAFC 040303
WSWALU

URGENT - WINTER WEATHER MESSAGE
NATIONAL WEATHER SERVICE ANCHORAGE AK
703 PM AKDT THU NOV 3 2011


AKZ152-040415-
/X.EXP.PAFC.WW.Y.0021.000000T0000Z-111104T0300Z/
LOWER KUSKOKWIM VALLEY-
INCLUDING THE CITIES OF...ANIAK...SLEETMUTE
703 PM AKDT THU NOV 3 2011

...WINTER WEATHER ADVISORY HAS EXPIRED...

THE WINTER WEATHER ADVISORY IS NO LONGER IN EFFECT. 

THE FRONT THAT HAS SUPPORTED SNOW ACROSS THE REGION CONTINUES TO
MOVE EASTWARD. IN ADDITION...TEMPERATURES ARE STARTING TO RISE
ABOVE FREEZING BEHIND THE FRONT AND MIXED PRECIPITATION IS
EXPECTED INSTEAD OF STEADY SNOW.

$$

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

.ANALYSIS AND UPPER LEVELS...UPPER LEVEL PATTERN IS PROGRESSIVE BUT
AMPLIFIED. WATER VAPOR IMAGERY SHOWS A STRONG RIDGE EXTENDING FROM
THE NORTH CENTRAL PACIFIC UP INTO THE EASTERN BERING WITH HIGH
AMPLITUDE TROUGHS ON EITHER SIDE OF IT. THE SUBTROPICAL JET RIDES
UP AND OVER THIS RIDGE WITH THE STRONGEST WINDS ON THE DOWNSTREAM
SIDE. THIS IS CAUSING THE LOW THAT AFFECTED SOUTHCENTRAL AND THE
GULF YESTERDAY TO MAKE A RAPID EXIT ACROSS THE NORTHEAST PACIFIC.
THE PRESSURE GRADIENT REMAINS QUITE TIGHT ACROSS SOUTHCENTRAL...
PARTIALLY DUE TO ARCTIC AIR ADVECTING ACROSS THE COASTAL MOUNTAIN
RANGES CAUSING LOWER PRESSURE ON THE LEE SIDE. SYNOPTIC SUBSIDENCE
ON THE POLEWARD SIDE OF THE SUBTROPICAL JET AND MORE FOCUSED
SUBSIDENCE WITH A SHORT-WAVE DROPPING THROUGH SOUTHCENTRAL THIS
MORNING ARE CONTRIBUTING TO MIXING DOWN OF STRONGER WINDS FROM
ALOFT. SO AFTER WINDS DIMINISHED A BIT OVERNIGHT THEY HAVE INCREASED
THIS MORNING IN MANY LOCATIONS.

THE NEXT MAJOR SYSTEM IS BEGINNING TO TAKE SHAPE OUT ACROSS THE
WESTERN ALEUTIANS AND BERING SEA. A MODERATE STRENGTH LOW APPROACHING

THE WESTERN ALEUTIANS HAS BECOME VERY ELONGATED DUE TO THE STRONG
SOUTHERLY JET JUST TO ITS EAST. EXPECT TO SEE A TRIPLE POINT LOW
DEVELOP THIS AFTERNOON WELL NORTH OF THE PARENT LOW AND STRENGTHEN
WITH THE HELP OF THE UPPER JET.

.MODEL DISCUSSION...THERE ARE SOME MINOR POSITION DIFFERENCES WITH
TRACK OF LOWS WHICH WILL MAKE LITTLE DIFFERENCE TO THE FORECAST.
OTHERWISE...MODELS ARE IN VERY GOOD AGREEMENT AND SHOW GOOD
RUN-TO-RUN CONSISTENCY. FORECAST CONFIDENCE IS ABOVE AVERAGE
FOR THIS NEXT STORM SYSTEM.

.SHORT TERM FORECAST...

SOUTHCENTRAL ALASKA...WINDS WILL DIE DOWN RAPIDLY ACROSS MOST OF
SOUTHCENTRAL ALASKA THIS AFTERNOON AND EVENING AS HIGH PRESSURE
BUILDS IN FROM THE WEST...HOLDING ON LONGEST ALONG COASTAL LOCATIONS.

A POWERFUL BERING SEA STORM WILL SEND A STRONG FRONT INTO THE GULF
AND SOUTHCENTRAL DURING THE DAY THURSDAY SO EXPECT CONDITIONS TO
RAPIDLY DETERIORATE. THE GREATEST IMPACT FROM THIS STORM WILL BE
STRONG WINDS. THE COMBINATION OF A STRONG FRONT AND TRACK OF THE
BERING SEE LOW TO SOUTHWEST ALASKA IT IS A CLASSIC SET-UP FOR HIGH
WINDS ALONG WESTERN TURNAGAIN ARM AND HIGHER ELEVATIONS THURSDAY
AFTERNOON AND NIGHT...SO WILL ISSUE A HIGH WIND WARNING WITH THE
NEW FORECAST PACKAGE. ALTHOUGH WINDS ARE EXPECTED TO REMAIN BELOW
WARNING CRITERIA OVER THE REST OF THE LAND AREA...WIDESPREAD GALES
WILL AFFECT THE MARINE AREAS. WITH A COLD AIR MASS IN PLACE
PRECIPITATION WILL START AS SNOW IN MOST AREAS. THE COMBINATION OF
SNOW WITH INCREASING WINDS WILL RESULT IN AREAS OF LOW VISIBILITIES
IN BLOWING SNOW. HOWEVER...THE STRONGEST WINDS WILL OCCUR IN COASTAL
LOCATIONS WHERE TEMPERATURES WILL WARM UP THE QUICKEST...SO EXPECT
THESE LOW VISIBILITIES TO BE SHORT-LIVED. THE WARMER AIR WILL ALSO
CHANGE SNOW TO RAIN ALONG THE COAST. THE SUSITNA VALLEY HOWEVER WILL
REMAIN ALL SNOW AND STRONG SOUTH TO SOUTHEAST LOW LEVEL WINDS WILL
ENHANCE THE SNOWFALL OVER PORTIONS OF THE VALLEY. A WINTER WEATHER
ADVISORY WILL BE ISSUED TO HIGHLIGHT THIS THREAT. THERE WILL BE SOME
INITIAL OVERRUNNING AHEAD OF THE FRONT WHICH COULD BRING SOME LIGHT
SNOW TO ANCHORAGE AND THE MAT VALLEY...BUT EXPECT STRONG SOUTHEAST
WINDS TO RAPIDLY DEVELOP AND CAUSE DOWNSLOPE DRYING. SO EXPECT
LITTLE OR NO SNOW ON THE LEE SIDE OF THE CHUGACH AND KENAI MOUNTAINS.

A TRIPLE POINT LOW WILL DEVELOP NORTHEAST OF KODIAK ISLAND THURSDAY
NIGHT WHICH WILL CAUSE LOW LEVEL FLOW TO BACK OVER INTERIOR
SOUTHCENTRAL AND DIMINISH SNOWFALL OR IN SOME AREAS CUT IT OFF
COMPLETELY. AS HAS OCCURRED WITH THE LAST COUPLE SYSTEMS IN THIS
AMPLIFIED FLOW ARCTIC AIR WILL MOVE IN BEHIND THE TRIPLE POINT
LOW BRINGING STORM FORCE WINDS TO THE WESTERN GULF AND LIKELY SOME
SNOW TO THE REST OF SOUTHCENTRAL AS WE HEAD INTO THE WEEKEND.

SOUTHWEST ALASKA...STRONG WINDS AND MODERATE TO HEAVY PRECIPITATION
WILL ARRIVE ALONG THE SOUTHWEST COAST LATE THIS EVENING INTO THE
OVERNIGHT HOURS AND SPREAD INLAND THURSDAY. PRECIP WILL INITIALLY
START AS SNOW WHICH WILL CAUSE BLOWING SNOW ISSUES. WARMER AIR WILL
QUICKLY MOVE INTO THE BRISTOL BAY COASTAL REGION SHORTLY AFTER PRECIP
ARRIVES WHICH WILL WARM TEMPERATURES TO NEAR FREEZING AND PREVENT
BLIZZARD CONDITIONS. THE WARMER AIR WILL TAKE LONGER TO REACH THE
KUSKOKWIM DELTA COASTAL AREA...ESPECIALLY THE NORTHERN COAST UP TO
AROUND HOOPER BAY. THEREFORE...PLAN TO UPGRADE TO A BLIZZARD WARNING
FOR THE COAST. FOR INTERIOR SOUTHWEST ALASKA THERE WILL BE A AS MUCH
AS 9 TO 12 HOURS OF SNOW ACCUMULATION PRIOR TO ENOUGH WARM AIR MOVING
INTO TO CAUSE MIXING WITH RAIN OR A COMPLETE CHANGEOVER SO WILL
INCREASE TO ADVISORY AMOUNTS FOR THESE AREAS (6 INCHES OR MORE).
STRONG WINDS WILL ALSO MAKE IT INTO INTERIOR BRISTOL BAY AHEAD OF
THE FRONT. WITH TEMPERATURES EXPECTED TO HOVER NEAR FREEZING FOR
MUCH OF THIS TIME WILL GO WITH A WINTER WEATHER ADVISORY OVER A
BLIZZARD WARNING. COLD AIR IS HARD TO SCOUR OUT OF THE KUSKOKWIM
VALLEY SO AS WARM AIR OVERRIDES THIS COLD AIR COULD ALSO SEE SOME
FREEZING RAIN...BUT THE BULK OF PRECIP WILL BE IN THE FORM OF SNOW.
THE LOW WILL TRACK ACROSS SOUTHWEST ALASKA TO THE INTERIOR ON FRIDAY
SO ARCTIC AIR WILL MOVE BACK IN AND CHANGE ANY REMAINING PRECIP TO
SNOW.

BERING SEA/ALEUTIANS...AN ALREADY STRONG SOUTHERLY LOW LEVEL JET
AHEAD OF THE COLD FRONT WILL STRENGTHEN FURTHER THIS AFTERNOON
AND EVENING AS NEWLY FORMED TRIPLE POINT LOW DEEPENS. THE NAM
MODEL IS STRONGEST WITH 90 KT AT AROUND 850 MB...BUT THE OTHER
MODELS AREN'T FAR BEHIND. WITH UPWARD VERTICAL MOTION DON'T EXPECT
THESE WINDS TO REACH THE SURFACE BUT IT GIVES AN IDEA OF JUST HOW
STRONG THE LOW LEVEL WINDS WILL BE. MOUNTAIN WAVES AND GAP WINDS
WILL ADD TO ALREADY STRONG SYNOPTIC WINDS TO PRODUCE DANGEROUS
HIGH WINDS FROM THE EASTERN ALEUTIANS TO SOUTHERN ALASKA PENINSULA
AS THE FRONT MOVES THROUGH. WINDS ON THE BACK SIDE OF THE LOW WILL
ALSO BE QUITE STRONG DUE TO WEAK COLD ADVECTION AND RAPID PRESSURE
RISES ON THE ORDER OF 2 TO 3 MB PER HOUR. THERE IS POTENTIAL FOR
THE EASTERN ALEUTIANS AND SOUTHERN ALASKA PENINSULA TO REACH HIGH
WIND CRITERIA AGAIN...BUT WILL WAIT UNTIL THE CURRENT WARNINGS ARE
OVER BEFORE CONSIDERING ISSUING NEW WARNINGS.

AS THIS FIRST STORM EXITS ANOTHER WILL ENTER THE WESTERN BERING ON
FRIDAY...BUT IT IS EXPECTED TO BE CONSIDERABLY WEAKER DUE TO A LESS
AMPLIFIED UPPER JET.

.LONG TERM FORECAST...UPPER PATTERN LOOKS MORE ZONAL THROUGH THE
EXTENDED PERIOD WHICH MEANS STORMS WILL MOVE EVEN FASTER FROM WEST
TO EAST ACROSS THE REGION BUT WON'T BE AS STRONG AS THE ONES
WE ARE CURRENTLY EXPERIENCING. ACTIVE WEATHER WILL CONTINUE.

.AER/ALU...WATCH/WARNING SUMMARY
PUBLIC...HIGH WIND WARNING 131 181 185.
         BLIZZARD WATCH 155.
MARINE...STORM WARNING...155 165 170 171 172 179 180 185.
         GALE WARNING...120 125 127 128 130 132 138 140 141
                        150 160 175 176.
FIRE WEATHER...NONE.

SEB NOV 11