Gale Warning 1031, NWS Anchorage, AK

SOUTHCENTRAL AND SOUTHWEST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE ANCHORAGE AK
500 AM AKST FRI DEC 3 2010

.MODEL DISCUSSION...00Z MODELS IN BASIC AGREEMENT ON DEPICTION
OF DEEP VERTICALLY STACKED LOW CURRENTLY JUST W OF PRIBILOFS.
AND WITH MOVEMENT THROUGH SHORT TERM OF IT AND STRONG OCCLUDED
FRONTAL SYSTEM...AIDED BY 150KT SWRLY JET JUST S OF EASTERN
ALEUTIANS/AK PEN. USED NAM FOR IT'S HANDLING OF TRIPLE POINT
LOW FORECAST TO MOVE NE UP COOK INLET LATER TODAY/TONIGHT.

.ANALYSIS AND UPPER LEVELS...500 DM UPPER LOW NEAR PRIBILOFS
TO SLOWLY MOVE E TODAY/TONIGHT...MOVING ASHORE OVER Y-K DELTA
12Z SAT. IT WILL THEN WEAKEN SIGNIFICANTLY AND DROP S INTO WRN
GULF AK AND N PAC SAT NIGHT/SUN AS UPPER RIDGING AMPLIFIES N
OVER BC AND SE AK. OCCLUDED FRONT STALLS OVER ERN GULF COAST
SAT...THEN ROLLS BACK W AS A WARM FRONT SAT NIGHT/SUN AS UPPER
RIDGING AMPLIFIES TO THE E.

.SHORT TERM FORECAST...BLIZZARD CONDITIONS SW MAINLAND ENDING
QUICKLY BY THIS AFTERNOON AS FRONT MOVES E. INCREASING WINDS AND
SNOW S CENTRAL TODAY...HEAVIEST AMOUNTS SUSITNA VALLEY W OF
PARKS HIGHWAY. STRONG WINDS LIKELY TURNAGAIN ARM AND ANCHORAGE
HILLSIDE LATER TODAY AND THIS EVENING. AIRMASS REMAINING COLD
ENOUGH FOR SNOW AND WIND TO COMBINE FOR BLIZZARD CONDITIONS
HOMER BENCH TODAY...AND THIS AFTERNOON/EVENING PRINCE WILLIAM
SOUND...PORTAGE VALLEY...AND EASTERN TURNAGAIN ARM. SNOW WILL
DIMINISH ALL AREAS EXCEPT SUSITNA VALLEY W OF THE PARKS HIGHWAY
THIS EVENING AS FRONT MOVES E. SCATTERED SNOW SHOWERS ALL AREAS
SAT...MIXED WITH RAIN IN KODIAK. PRECIP. WILL START AS SNOW IN
KODIAK THIS MORNING...BUT WILL QUICKLY CHANGE TO RAIN. INCREASING
-SHRASN ERN ALEUTIANS AND AK PEN TODAY...CHANGING TO ALL SNOW BY
LATE TONIGHT AS COLD ADVECTION AND GUSTY NW WINDS ON BACK SIDE
OF LOW MOVE IN...CONTINUING THROUGH SAT.

.LONG TERM FORECAST...RIDGING BUILDS IN OVER SE AK...S-CENTRAL
AND ERN INTERIOR SUN-TUE. WEAK UPPER TROUGHING REMAINS OVER SW
AND WRN MAINLAND AK. UPPER RIDGING BUILDING N OVER WRN ALEUTIANS
LATE SAT/SUN REMAINS NEARLY STATIONARY AND FORMS CLOSED CENTER
BY TUE. RAIN/SNOW WILL ROLL BACK W ALONG GULF COAST TO PRINCE
WILLIAM SOUND SUN...AND KENAI SUN NIGHT...AND KODIAK MON. LIGHTER
PRECIP. LIKELY INLAND S-CENTRAL AND COPPER RIVER BASIN SUN AND
SUN NIGHT. SHOULD BE COLD ENOUGH FOR SNOW MOST AREAS S-CENTRAL.
SNOW SHOWERS WITH STRONG NRLY WINDS ERN ALEUTIANS/AK PEN SUN
WILL DIMINISH MON AS UPPER RIDGING BUILDS IN FROM THE W.

.AER/ALU...WATCH/WARNING SUMMARY
PUBLIC...BLIZZARD WARNING 121 125 131 135 161
         HIGH WIND WARNING 101
         WINTER STORM WARNING HEAVY SNOW 145
MARINE...STORM 120 125 130
          GALE 150 155 160 165 170 171 172 175 176 179 180 185
               129 132 138 140 141 411 412 413 414 351 352 127
               128
          HEAVY FREEZING SPRAY 127

FIRE WEATHER...NONE

MAR DEC 10

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE ANCHORAGE AK
1140 AM AKST FRI DEC 3 2010

AKZ101-040400-

...HAZARDOUS WINTER CONDITIONS IN ANCHORAGE LATER TODAY...

A LOW PRESSURE SYSTEM TRACKING NORTH UP COOK INLET TODAY HAS THE
POTENTIAL TO BRING A SHORT PERIOD OF HAZARDOUS CONDITIONS TO THE
ANCHORAGE AREA LATE THIS AFTERNOON. WINDS HAVE INCREASED RAPIDLY TO
NEAR 80 MPH ALONG TURNAGAIN ARM AND PORTIONS OF THE HILLSIDE THIS
MORNING...AND WILL CONTINUE THROUGH EARLY EVENING. AS THE LOW TRACKS
CLOSER TO ANCHORAGE IN THE EARLY AFTERNOON HOURS...WINDS WILL SPREAD
NORTHWARD AND AFFECT THE ANCHORAGE BOWL. SOUTHEAST WINDS OF 20 TO 30
MPH WITH GUSTS TO 45 MPH ARE POSSIBLE BY LATER IN THE AFTERNOON AND
INTO THE EVENING. WIDESPREAD SNOW WILL ALSO DEVELOP AROUND THE TIME
THESE WINDS MOVE INTO THE ANCHORAGE AREA...CREATING THE POTENTIAL FOR
BLOWING SNOW AND SIGNIFICANTLY REDUCED VISIBILITY DURING THE
AFTERNOON RUSH HOUR.

ANY STRONG WINDS IN ANCHORAGE WILL BE SHORT LIVED...DECLINING
SIGNIFICANTLY AND SWITCHING TO THE SOUTH BY MID EVENING.
HOWEVER...DURING THIS TIME SNOW WILL INCREASE IN
INTENSITY...ACCUMULATING SEVERAL INCHES BY MIDNIGHT...BEFORE TAPERING
OFF TO SNOW SHOWERS IN THE EARLY MORNING HOURS.

MANY OF THE IMPACTS WITH THIS STORM SYSTEM WILL DEPEND ON THE EXACT
TRACK OF THE LOW...WHICH STILL INCLUDES SOME UNCERTAINTY. STAY TUNED
TO NOAA WEATHER RADIO OR YOUR LOCAL MEDIA OUTLETS FOR THE LATEST
DETAILS ON THIS STORM. THIS INFORMATION CAN ALSO BE OBTAINED ONLINE
AT WWW.WEATHER.GOV/ANCHORAGE.

AMD/KS/JHW/BH