Ice Storm Warning 1, NWS Anchorage, AK

642 
WWAK42 PAFC 140056
WSWALU

URGENT - WINTER WEATHER MESSAGE
NATIONAL WEATHER SERVICE ANCHORAGE AK
356 PM AKST TUE NOV 13 2012


AKZ155-141400-
/X.CAN.PAFC.IS.W.0001.000000T0000Z-121114T0300Z/
/X.NEW.PAFC.ZR.Y.0007.121114T0100Z-121114T1400Z/
KUSKOKWIM DELTA-
INCLUDING THE CITIES OF...BETHEL...HOOPER BAY...NUNIVAK ISLAND
356 PM AKST TUE NOV 13 2012

...FREEZING RAIN ADVISORY IN EFFECT UNTIL 5 AM AKST WEDNESDAY... 
...ICE STORM WARNING IS CANCELED...

THE NATIONAL WEATHER SERVICE IN ANCHORAGE HAS ISSUED A FREEZING
RAIN ADVISORY...WHICH IS IN EFFECT UNTIL 5 AM AKST WEDNESDAY. THE
ICE STORM WARNING HAS BEEN CANCELED.

* ICE ACCUMULATION...ONE TENTH OF AN INCH OR LESS.

* TIMING...AREAS OF FREEZING RAIN WILL CONTINUE THROUGH 5 AM AKST
  WEDNESDAY.

* IMPACTS...EXPOSED SURFACES MAY BECOME SLIPPERY. TRAVEL MAY BE
  DANGEROUS.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A FREEZING RAIN ADVISORY MEANS THAT PERIODS OF FREEZING RAIN OR
FREEZING DRIZZLE WILL CAUSE TRAVEL DIFFICULTIES. BE PREPARED FOR
SLIPPERY ROADS. SLOW DOWN AND USE CAUTION WHILE DRIVING.

&&



$$

SOUTHCENTRAL AND SOUTHWEST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE ANCHORAGE AK
400 PM AKST MON NOV 12 2012

.ANALYSIS AND UPPER LEVELS...THE BIG STORY OF THE DAY AND FOR THE
NEXT FEW DAYS IS THE LARGE SURFACE LOW CURRENTLY IN THE WESTERN
ALEUTIANS. THIS LOW WILL TRACK NEAR THE PRIBILOF ISLANDS BY TUESDAY
AFTERNOON AND THEN INTO THE GULF OF ALASKA BY EARLY THURSDAY. THE
STRONG FRONT IS PUSHING WINDS AND PRECIPITATION WELL AHEAD OF THE LOW
TRACK AND WILL BE A BIG FACTOR IN SOUTHWEST ALASKA BY EARLY TOMORROW.

THE UPPER LEVEL PATTERN IS WHAT ONE WOULD EXPECT FOR A STRONG LOW IN
THE WESTERN ALEUTIANS. THERE IS AN UPPER LEVEL LOW NEAR KAMCHATKA AND
TROUGH EXTENDING OUT OF THAT LOW OVER THE SURFACE LOW WITH A HIGH
AMPLITUDE RIDGE OVER SOUTHWEST ALASKA. THE JET STREAM REMAINS
FAVORABLY POSITIONED FOR SUSTAINING THE STRENGTH OF THIS LOW FOR THE
NEXT DAY. A NORTHWEST JET IS MOVING OVER SOUTH CENTRAL AHEAD OF THE
RIDGE AXIS.

.MODEL DISCUSSION...MODELS ARE IN GOOD OVERALL AGREEMENT BUT WITH
ENOUGH DIFFERENCES IN DETAILS TO KEEP THINGS INTERESTING. THERE ARE
THE USUAL DIFFERENCES IN THE POSITION OF THE WEAK LOW CENTERS IN THE
LOW COMPLEX IN THE EASTERN GULF BUT THAT WILL NOT HAVE ANY REAL
IMPACT OF THE FORECASTS. THE LARGE LOW IN THE CENTRAL AND WESTERN
ALEUTIANS IS TRACKING WELL WITH THE GFS AND ITS SLIGHTLY MORE
NORTHERLY COURSE. LIKE YESTERDAY THIS DIFFERENCE DISAPPEARS A DAY OR
SO OUT SO IT IS NOT A BIG IMPACT BUT THE GFS IS STILL THE MODEL OF
CHOICE FOR RESOLVING THIS LOW IN THE BERING SEA.
THINGS DO GET A LITTLE TRICKIER IN THE NORTHERN GULF TUESDAY EVENING
THROUGH WEDNESDAY. MODELS AGREE ON THE DEVELOPMENT OF A TRIPLE POINT
NEAR THE SOUTHERN TIP OF THE KENAI PENINSULA BUT DIFFER IN TRACK AND
STRENGTH OF IT. THE NAM IS PROBABLY THE BEST OF THE BUNCH WITH ITS
TRACK BUT THE STRENGTH OF THE LOW IS PROBABLY TOO MUCH. THERE IS NOT
ENOUGH COLD AIR AVAILABLE TO STREAM THROUGH THE KAMISHAK GAP AND
STRENGTHEN IT TO SUPPORT THE 12Z NAM STRENGTH. THE 18Z NAM IS SHOWING
THE BEST SOLUTION SO FAR AS IT HAS A SIMILAR TRACK INTO PRINCE
WILLIAM SOUND AS THE 12Z NAM BUT IS A LITTLE WEAKER. THIS IS PROBABLY
STILL A LITTLE TOO STRONG BUT NOT BY MUCH. THE GFS TRACK HAS BEEN A
BIT WOBBLY FROM RUN TO RUN RANGING FROM BRINGING THE LOW UP THE
CENTER OF COOK INLET TO BRINGING IT IN A SIMILAR TRACK TO THE NAM.
THE TRACK UP THE INLET IS UNLIKELY WITH THE PATH THE MAIN LOW IS
TRACKING. THE MAIN LOW WOULD NEED TO BE FARTHER NORTH FOR THE COOK
INLET SOLUTION TO MAKE SENSE. THEREFORE THE FAVORED SOLUTION IS A NAM
TRACK WITH A LOW A LITTLE WEAKER THAN THE 18Z NAM.

.SHORT TERM FORECAST...
BERING SEA ND ALEUTIANS...THE HIGH WIND WARNINGS CONTINUE INTO
TUESDAY IN THE CENTRAL AND WESTERN ALEUTIANS WITH THE STRONG LOW IN
THE AREA. THE WARM SYSTEM WILL KEEP PRECIPITATION RAIN EXCEPT FOR THE
SHEMYA AND ATTU AREAS WHICH WILL REMAIN COLD ENOUGH TO MIX IN SOME
SNOW. EVEN WITH SOME SNOW MIXED IN AND HIGH WINDS IT LOOKS LIKE IT
WILL REMAIN WARM ENOUGH THAT THERE WILL NOT BE MUCH OF A THREAT OF
BLIZZARD CONDITIONS.

SOUTHWEST...THE AREAS OF LOW CLOUDS AND FOG SHOULD MIX OUT AND BEGIN
TO CLEAR UP AS THE FRONT APPROACHES THE AREA AND BRINGS BETTER MIXING
TO THE ATMOSPHERE. THE BIG CONCERN WILL BE THE THREAT OF FREEZING
RAIN...ESPECIALLY FROM DILLINGHAM WESTWARD THROUGH THE KUSKOKWIM
DELTA. THE CONDITIONS LOOK FAVORABLE ENOUGH IN THE KUSKOKWIM DELTA
THAT THERE IS A FREEZING RAIN ADVISORY FOR THAT AREA. IN THE BRISTOL
BAY REGION THE FREEZING RAIN LOOKS MORE LIKELY FROM DILLINGHAM
WESTWARD WITH AREAS EASTWARD WARMING ABOVE FREEZING BEFORE
SIGNIFICANT FREEZING RAIN CAN DEVELOP.

SOUTH CENTRAL...PARTLY CLOUDY WITH AREAS OF FOG WILL BE THE GENERAL
RULE FOR SOUTH CENTRAL INTO TOMORROW MORNING. CLOUDS WILL MOVE IN
FROM THE SOUTHWEST BY TUESDAY AFTERNOON IN THE COOK INLET REGION AND
TUESDAY NIGHT TOWARD THE COPPER RIVER BASIN AS THE FRONT ASSOCIATED
WITH THE LARGE LOW MOVES INTO THE AREA. THE DEVELOPMENT AND TRACK OF
THE TRIPLE POINT LOW WAS DISCUSSED IN THE PREVIOUS SECTION AND THIS
TRIPLE POINT WILL BE A KEY TO PRECIPITATION AND PRECIPITATION TYPE
ESPECIALLY IN THE ANCHORAGE AREA. IT LOOKS LIKE SNOW SHOULD MOVE UP
COOK INLET BEGINNING EARLY TUESDAY EVENING AND INTO THE SUSITNA
VALLEY TOWARD MIDNIGHT. BOTH NAM AND GFS SOLUTIONS BRING IN SNOW TO
THESE AREAS WITH RAIN NOT MAKING IT MUCH FARTHER NORTH THAN HOMER.
THE FAVORED SOLUTION IS ACTUALLY THE ONE THAT HAS THE BEST CHANCE OF
BRINGING A GOOD ACCUMULATION OF SNOW TO THE ANCHORAGE AREA TUESDAY
NIGHT INTO WEDNESDAY.

.LONG TERM FORECAST...THE STORM THAT IS IMPACTING THE ALEUTIANS
THROUGH THE GULF WILL PUSH EAST AT THE END OF THE WEEK. THIS PATTERN
WILL BE REPLACED BY AN AMPLIFIED RIDGE THAT BUILDS OVER THE CENTRAL
BERING AND AN ARCTIC FRONT WILL EVENTUALLY PUSH THROUGH THE ENTIRE
AREA. DRIER CONDITIONS AND COLDER TEMPERATURES WILL MOVE INTO THE
AREA BY THE WEEKEND.

.AER/ALU...WATCH/WARNING SUMMARY
PUBLIC...HIGH WIND WARNING 187 191.
         HIGH WIND WATCH 185.
         FREEZING RAIN ADVISORY 155.
MARINE...HURRICANE FORCE WIND 172 175 176.
         STORM 170 171 179 185.
         GALE 150 155 160 165 180.
FIRE WEATHER...NONE.

EZ NOV 12