Winter Storm Watch 4, NWS Fairbanks, AK

NORTHERN ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE FAIRBANKS AK
1248 PM AKDT WED MAR 21 2012

.DISCUSSION...
COLD LOW PRESSURE ALOFT OVER CENTRAL AND EASTERN ALASKA WILL
SLOWLY WEAKEN AS IT MOVES EAST INTO WESTERN CANADA THROUGH THE
WEEKEND. A HIGH AMPLITUDE HIGH PRESSURE RIDGE OVER EASTERN
SIBERIA WILL SPLIT AS IT MOVES OVER WESTERN ALASKA THROUGH THE
WEEKEND. THE SOUTHERN PORTION OF THE HIGH PRESSURE RIDGE WILL MOVE
EAST INTO THE NORTHERN GULF OF ALASKA WHILE THE NORTHERN PORTION
OF THE RIDGE BECOMES A CUTOFF HIGH PRESSURE AND MOVES OVER THE THE
CHUKCHI SEA BY SATURDAY MORNING.

THE PRESSURE GRADIENT ACROSS THE BROOKS RANGE HAS DIMINISHED WHERE
WIND CHILL ADVISORIES ARE NO LONGER WARRANTED FOR ZONES 206 AND
217 HOWEVER WINDS IN ZONES 207 AND 213 REMAIN STRONG ENOUGH
COMBINED WITH WITH LOW TEMPERATURES FOR THE WIND CHILL ADVISORIES
TO BE EXPENDED THROUGH TOMORROW MORNING.

SYNOPTIC SCALE MODELS ARE IN REASONABLE AGREEMENT WITH
SIGNIFICANT HEIGHT RISES FOR THE INTERIOR AND BERING SEA COAST OF
ALASKA THROUGH THE WEEKEND. AS THE HIGH PRESSURE RIDGE MOVES
EASTWARD OVER ALASKA HIGH TEMPERATURES WILL INCREASE TO NEAR
NORMAL ACROSS THE INTERIOR. LIMITED CLOUD COVER WILL ALLOW FOR
NIGHT TIME TEMPERATURES TO REMAIN CHILLY AS NOCTURNAL INVERSIONS
SET UP ACROSS THE INTERIOR IN WIND SHELTERED LOCATIONS. WINDS
WILL INCREASE ALONG AND THROUGH THE ALASKA RANGE AND THE ALASKA
RANGE PASSES WITH MODERATE GAP FLOWS EXPECTED TO DEVELOP BY
FRIDAY. MILD CHINOOK CONDITIONS ARE EXPECTED ACROSS THE SOUTHERN
INTERIOR THIS WEEKEND.

&&

.AFG WATCHES/WARNINGS/ADVISORIES...
WIND CHILL ADVISORY FOR AKZ207-AKZ213.

BRISK WIND ADVISORY FOR PKZ210.
&&

CC MAR 12