Gale Warning 234, NWS Anchorage, AK

AREA FORECAST DISCUSSION
SOUTHCENTRAL AND SOUTHWEST ALASKA
500 AM AST WED MAR 01 2006

.DISCUSSION...

CURRENT WEATHER PATTERN HAS MUCH OF MAINLAND ALASKA UNDER THE
INFLUENCE OF AN UPPER LEVEL RIDGE WITH SURFACE HIGHS OVER NORTH
CENTRAL AK AND SOUTH OF THE AK PEN AROUND 45N. A DECAYING LOW IS
SPINNING DOWN OVER THE SOUTHEASTERN GULF WHILE IN THE WEST THE
DOMINANT FEATURE IS A LARGE LOW CENTERED NEAR THE ANADYR GULF WITH A
FRONT EXTENDING ACROSS THE CENTRAL BERING SEA AND CENTRAL ALEUTIANS.
THIS FRONTAL SYSTEM IS THE HIGH IMPACT HAZARD OF THE DAY WITH STRONG
WINDS EXPECTED ACROSS THE Y K DELTA...IN FACT GUSTS TO 50 KTS ARE
CURRENTLY BEING REPORTED AT CAPE ROMANZOF. WITH AN AMPLE MOISTURE
PRESENT...HIGH WINDS AND SNOWFALL ARE EXPECTED TO BRING BLIZZARD
CONDITIONS THIS MORNING TO THE KUSKOKWIM DELTA WITH THE GREATEST
THREAT BEING ALONG THE COAST AND NUNIVAK ISLAND AS THE FRONT MOVES
ONSHORE. THE STANDARD REGIME OF COLD ADVECTION INSTABILITY SNOW
SHOWERS ARE BEING OBSERVED ACROSS THE WESTERN BERING SEA BEHIND THE
FRONT.

EXPECT BLIZZARD CONDITIONS TO CONTINUE THROUGH THE DAY ALONG THE Y K
DELTA AS THE FRONT MOVES ONSHORE. THE PRESSURE GRADIENT ALONG THE
FRONT WILL NOT BE QUITE AS TIGHT FARTHER SOUTH ALONG BRISTOL
BAY...HOWEVER CONDITIONS THERE WILL STILL BE BREEZY ENOUGH TO WARRANT
A BLOWING SNOW ADVISORY FROM LATE THIS AFTERNOON AND THROUGH THE
OVERNIGHT HOURS. AS THE FRONT MOVES ONSHORE IT SHOULD BEGIN TO FALL
APART BY THU MORNING.

IN THE MEANTIME A SHORTWAVE UPPER LEVEL TROUGH OVER THE CENTRAL
ALEUTIANS WILL DIG SOUTHEAST ACROSS THE EASTERN ALEUTIANS THU MORNING
IN RESPONSE TO ANOTHER VORTMAX MOVING INTO THE BASE OF THE TROUGH
WITH A CORRESPONDING SURFACE LOW DEVELOPING OVER THE AK PEN. BY EARLY
FRI MORNING A SPLIT FLOW PATTERN IS EVIDENT WITH AN UPPER RIDGE WITH
AN AXIS RUNNING EAST TO WEST FROM THE NORTHWEST TERRITORIES INTO
INTERIOR AK. THE SHORTWAVE TROUGH TURNS INTO A CUTOFF LOW AND GETS
CARRIED SOUTHEAST AROUND THIS RIDGE ALONG WITH THE SURFACE LOW BY THE
WESTERLIES...THUS MISSING SOUTHCENTRAL AK AND ALLOWING IT TO STAY DRY
INTO THE WEEKEND. THE REMAINING ENERGY ASSOCIATED WITH THE ANCHOR
UPPER LEVEL LOW OVER THE WESTERN BERING ROTATES ACROSS WESTERN AND
CENTRAL AK ON LATE FRI AND INTO SAT...ALLOWING FOR CHANCE POPS IN THE
SOUTHWEST AND SLIGHT CHANCE POPS OVER SOUTHCENTRAL. THE NEXT MAJOR
SYSTEM GETS SHUNTED ACROSS THE BERING SEA FRIDAY WITH A FRONT RAKING
THE ALEUTIANS BEFORE THE LOW MOVES ONSHORE OVER THE Y K DELTA
SATURDAY NIGHT BRINGING AT LEAST CHANCE POPS TO MUCH OF THE FORECAST
AREA OVER THE WEEKEND.

.AER/ALU...WATCH/WARNING SUMMARY
PUBLIC...BLIZZARD WARNING 155
MARINE...GALE 121 155 170 172 176 179 180 185
         HEAVY FREEZING SPRAY 121 129 130 140 180
FIRE WEATHER...NONE

WOOD FEB 06