Gale Warning 947, NWS Anchorage, AK

SOUTHCENTRAL AND SOUTHWEST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE ANCHORAGE AK
130 PM AKST SUN NOV 14 2010

.ANALYSIS AND UPPER LEVELS...
PATTERN CHANGE IN FULL SWING THIS MORNING AS THE RIDGE OVER THE
NORTHEASTERN PACIFIC HAS FLATTENED OUT AND THE TROUGH THAT HAS BEEN
IN PLACE OVER THE SOUTHWEST MAINLAND IS DISPLACED TO THE EAST. JET
ACTIVITY REMAINS SOUTH OF OUR DOMAIN FLOWING AROUND THE BASE OF THE
TROUGH TOWARD THE SOUTHERN PANHANDLE. A STRENGTHENING JET SOUTH OF
THE KAMCHATKA PENINSULA WILL PLAY A ROLE IN THE WEATHER FOR MUCH OF
ALASKA THROUGH THE EARLY PART OF NEXT WEEK.

.MODEL DISCUSSION...
MODELS CONTINUE TO BE IN EXCELLENT AGREEMENT THROUGH THE SHORT TERM.
ONLY MINOR ADJUSTMENTS ARE NEEDED TODAY TO THE FORECASTS.

.SHORT TERM FORECAST...
IN THE FIRST 24 HOURS...WILL HAVE TO ADDRESS THE CHANCE OF
PRECIPITATION AS THE COLD AIR SPILLS ACROSS THE ALASKA RANGE AND
FILTERS ACROSS SOUTHCENTRAL ALASKA. THE COLD AIR WILL BE ACCOMPANIED
BY A SIGNIFICANT SHORT WAVE ALOFT. AHEAD OF THIS WAVE...SOUTHWESTERLY
FLOW ALOFT WILL INSURE ENOUGH MOISTURE IS IN PLACE WHILE THE WAVE
ITSELF PROVIDES THE ADDITIONAL LIFT NECESSARY TO SQUEEZE OUT LIGHT
SNOW. SNOW WILL GENERALLY BE LIGHT WITH ONLY A FEW INCHES EXPECTED
ALONG THE MOUNTAINS...AND AN INCH OR LESS IN THE VALLEYS.

THEN THE COLD AIR ARRIVES MONDAY EVENING. AS HIGHLIGHTED IN THE
SPECIAL WEATHER STATEMENT...TEMPERATURES WILL DROP INTO THE TEENS
AREA WIDE FOR THE FIRST TIME THIS SEASON. WINDS WILL ALSO
INCREASE...COUPLED WITH THE COOLER TEMPERATURES WILL RESULT IN WIND
CHILL READINGS NEAR ZERO.

CHANNELED TERRAIN WILL SEE STRONGER WINDS...SPECIFICALLY ALONG THE
ALASKA RANGE AND AROUND PRINCE WILLIAM SOUND. MOST ZONES WILL BE
HEADLINED FOR STRONG WINDS THROUGH CHANNELED TERRAIN THROUGH TUESDAY
AND WEDNESDAY. PLACES LIKE THOMPSON PASS HAS TRANSPORTABLE SNOW SO
THE POTENTIAL FOR A GROUND BLIZZARD WILL HAVE TO BE CONSIDERED
TUESDAY THROUGH WEDNESDAY.

TEMPERATURES SLOWLY REBOUND THURSDAY AND FRIDAY AS THE AMPLIFIED
RIDGE TRANSITIONS EAST AND THE DIRTY SIDE OF THE RIDGE USHERS WARMER
AIR BACK TO THE REGION.

SOUTHWEST ALASKA...THE COLD AIR IS ALREADY SLIPPING SOUTH ACROSS THE
KUSKOKWIM RIVER VALLEY. TEMPERATURES IN THIS REGION ARE HOLDING
STEADY IN THE MID TEENS WHILE BRISTOL BAY IS SEEING TEMPS CLOSER TO
THE LOWER 30S. TEMPERATURES WILL DROP INTO THE SINGLE DIGITS BY
MONDAY NIGHT WITH LOCAL WIND CHILLS DIPPING BELOW ZERO. HIGH PRESSURE
CONTINUES TO BUILD THROUGH MID WEEK WITH TEMPERATURES HANGING CLOSER
TO CLIMATOLOGICAL NORMS LATER IN THE WEEK.

BERING SEA/ALEUTIANS...HIGH PRESSURE BUILDING QUICKLY OVER THE
WESTERN BERING SEA TODAY. THIS RIDGE WILL BECOME MUCH MORE AMPLIFIED
MONDAY AND SPREAD OVER THE CENTRAL BERING. COLD ADVECTION SHOWERS
WILL DIMINISH AS THE RIDGE BECOMES THE DOMINANT FEATURE ACROSS THE
AREA. IT IS NOT UNTIL LATER ON TUESDAY WHEN A FRONT APPROACHES THE
WESTERN ALEUTIANS BUT HAS A DIFFICULT TIME PROGRESSING BECAUSE OF THE
AMPLIFIED PATTERN.

.AER/ALU...WATCH/WARNING SUMMARY
PUBLIC...NONE.
MARINE...STORM 130
         GALE 121 127 129 132 150 175 176.
         HEAVY FREEZING SPRAY 130
FIRE WEATHER...NONE.

AB NOV 10

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE ANCHORAGE AK
1125 AM AKST SUN NOV 14 2010

AKZ101-111-150600-

...BIG CHANGES UPCOMING THIS WEEK...

A CHANGE IN THE PATTERN IS UNDER WAY ACROSS MOST OF ALASKA TODAY.
COLD AIR IS ADVANCING SOUTH AND EAST TOWARD SOUTHCENTRAL ALASKA AND
WILL ARRIVE IN ANCHORAGE AND THE MATANUSKA VALLEY BY MONDAY EVENING.
TEMPERATURES WILL DROP INTO THE TEENS MONDAY NIGHT AS THE WINDS
INCREASE...RESULTING IN WIND CHILL READINGS ZERO TO 10 ABOVE.
TEMPERATURES WILL REMAIN IN THE TEENS ON TUESDAY AS THE WINDS
CONTINUE TO BLOW FROM THE NORTH 15 TO 25 MPH IN ANCHORAGE AND HIGHER
GUSTS THROUGH PALMER AND WASILLA.

THE RECENT ABOVE AVERAGE TEMPERATURES HAS MELTED SOME OF THE SNOW
RESULTING IN WET ROADS ACROSS THE AREA. THE SUDDEN DROP IN
TEMPERATURES WILL LEAD TO THE ROAD SURFACES REFREEZING AND HAZARDOUS
DRIVING CONDITIONS.

AVERAGE TEMPERATURES FOR ANCHORAGE THIS TIME OF YEAR
----------------------------------------------------
HIGH....28
LOW.....16

OBSERVED TEMPERATURES THE LAST SEVERAL DAYS IN ANCHORAGE
-----------------------------------------------
            HIGH        LOW
THURSDAY     33         26
FRIDAY       34         28
SATURDAY     40         32

FORECAST TEMPERATURES THIS WEEK IN ANCHORAGE
----------------------------------------------
            HIGH        LOW
SUNDAY       38         32
MONDAY       28         24
TUESDAY      16         10
WEDNESDAY    18          8

TEMPERATURES ARE EXPECTED TO REBOUND LATER IN THE WEEK BACK TO NEAR
NORMAL.

AB