Winter Storm Warning 6, NWS Fairbanks, AK

NORTHERN ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE FAIRBANKS AK
133 PM AKST WED FEB 11 2009

.DISCUSSION...PATTERN CHANGE UNDERWAY TO WARMER...MORE
ACTIVE FOR ALL NORTHERN AK. 12Z MODELS IN BASIC AGREEMENT
ON KEY FEATURES. FIRST ONE IS WEAKENING 994 MB LOW NEAR
DATELINE/56N. DISSIPATING FRONTAL REMNANT WITH IT WILL
CONTINUE MOVING OVER ST LAWRENCE AND SEWARD PEN. TONIGHT
AND CHUKCHI SEA COAST FRI. IT WILL MERGE WITH WARM FRONTAL
FEATURE ASSOCIATED WITH NEXT STRONGER LOW.

THIS LOW...CURRENTLY AROUND 975 MB AT 48N/175E WILL DEEPEN
TO 960-965 MB BY 00Z THU WHEN IT MOVES TO AROUND 55N/177W.
TRIPLE POINT AND FRONTAL SYSTEM ASSOCIATED WITH IT WILL
MOVE N OVER ST LAWRENCE...BERING STRAIT...AND SEWARD PEN.
LATE THU AND CHUKCHI SEA COAST EARLY FRI. MAIN LOW WILL
WEAKEN SUBSTANTIALLY AS IT MOVES OVER BRISTOL BAY BY 00Z
SAT. UPPER RIDGING AHEAD OF THIS CURRENTLY DEEPENING LOW
WILL MOVE E OVER CENTRAL AK AND AMPLIFY N LATE THU/FRI.
THIS RIDGE WILL FORCE REMNANTS OF BERING LOW TO RIDE UP
OVER IT SAT IN SW FLOW OVER INTERIOR SAT. ANOTHER LOW WILL
MOVE OVER ALEUTIANS AND AK PEN. SUN/MON.

N SLOPE: FRONTAL REMNANT MOISTURE FROM FIRST BERING LOW
WILL MOVE N OVER WRN BROOKS RANGE AND WRN ARCTIC COAST THU.
SOME -SN POSSIBLE WITH THIS THEN INTO THU NIGHT ZONES 201
202 AND 205. TIGHTENING NE SURFACE PRESSURE GRADIENTS WILL
LEAD TO BWA LEVEL WINDS WRN ARCTIC COAST THU NIGHT AND BLSN.
MAIN FRONTAL BAND FROM SECOND LOW WILL MOVE OVER WRN ARCTIC
COAST AND WRN BROOKS FRI...BRINGING MORE WIDESPREAD SNOW AND
BLSN. NOT EXPECTING BLIZ. CONDITIONS AT THIS POINT.

W COAST: SNOW SHOWERS TONIGHT AND BLSN ST LAWRENCE AND BERING
STRAIT WITH FIRST FRONTAL REMNANTS AND TIGHTENING NE SURFACE
PRESSURE GRADIENT REQUIRES WINTER WEATHER ADVISORY TO REMAIN
IN PLACE. SLIGHT IMPROVEMENT IN CONDITIONS THU. WILL BE BRIEF
BEFORE WARM FRONTAL SNOW FROM DEEP LOW TO THE S MOVES OVER.
BLIZZARD CONDITIONS LIKELY THU. AFTERNOON TO AT LEAST 12Z FRI
ST LAWRENCE AND BERING STRAIT AS OCCLUDED FRONT MOVES OVER.
SHORTER PERIOD OF AT LEAST BWA LEVEL WINDS AND SNOWFALL OVER
ZONES 211/212/214 THU NIGHT STILL NECESSITATE KEEPING WINTER
STORM WATCH IN PLACE. AT THIS POINT...EXPECT JUST WINTER WEATHER
ADVISORY LEVEL SNOWFALL AND BLSN FOR CHUKCHI SEA COAST AND PAOT
AREA THU NIGHT AND FRI.

INTERIOR: WARMER PATTERN UNDERWAY. CLOUDS AND WARM AIR ADVECTION
IN SWRLY FLOW WILL KEEP HILL-SLOPE AND RIDGE TEMPERATURES WELL
ABOVE ZERO F TONIGHT...WHILE VALLEYS WILL CONTINUE WARMING TO
ABOVE ZERO F THU. LIGHT CHINOOK FLOW THU WILL STRENGTHEN FRI AS
RIDGING AMPLIFIES OVER ERN INTERIOR AND BERING LOW MOVES FURTHER
E. COULD SEE ADVISORY LEVEL CHINOOK WINDS AK RANGE PASSES FRI.
TEMPS. WILL WARM WELL INTO 20S THERE AND HILLS OVER INTERIOR FRI.
REMAINS OF BERING LOW/FRONTAL SYSTEM MAY BRING SOME -SN TO WRN
HALF INTERIOR SAT...BUT ONLY MINOR COOLING.

&&

.AFG WATCHES/WARNINGS/ADVISORIES...
WIND CHILL ADVISORY FOR AKZ210.

WINTER WEATHER ADVISORY FOR AKZ213.

WINTER STORM WATCH FOR AKZ211-AKZ212-AKZ213-AKZ214.

GALE WARNING FOR PKZ210.

BRISK WIND ADVISORY FOR PKZ200-PKZ210-PKZ220-PKZ225.
&&

MAR FEB 09