Blizzard Watch 10, NWS Anchorage, AK

AREA FORECAST DISCUSSION
SOUTHCENTRAL AND SOUTHWEST ALASKA
500 AM AST THU FEB 7 2008

.MODEL DISCUSSION...
MODELS IN OKAY AGREEMENT. HOWEVER ENSEMBLE GFS INDICATES CONSIDERABLE
UNCERTAINTY REGARDING TRACK OF THE NORTH PACIFIC LOW MOVING INTO THE
SOUTHERN GULF OF ALASKA THIS WEEKEND. NOT INTERESTED IN CHASING
SOLUTIONS AT THIS TIME. THEREFORE ONLY MINIMAL CHANGES MADE TO
FORECAST PACKAGE FROM FRIDAY NIGHT ONWARD.

.UPPER LEVELS...
UPPER LEVEL BLOCKING RIDGE ALONG ALASKAS WEST COAST HOLDS THROUGH AT
LEAST THE WEEKEND BUT IT DOES GRADUALLY WEAKEN. FLOW ALOFT BECOMES
MORE CONDUCIVE TO STEERING STORMS INTO THE GULF AND TOWARD MAINLAND
ALASKA BEGINNING SATURDAY.

.SURFACE FEATURES...
HIGH PRESSURE OVER INTERIOR ALASKA WILL WEAKEN AND RECEDE INTO
WESTERN CANADA BEGINNING EARLY FRIDAY. TROUGH OF LOW PRESSURE ALONG
THE GULF COAST ALSO BREAKS DOWN EARLY FRIDAY.
REMNANTS OF THE OLD FRONTAL BOUNDARY EXTEND FROM DUTCH HARBOR TO
AMCHITKA. AN ASSOCIATED 988 MB LOW NEAR ADAK WILL DISSIPATE JUST
SOUTH OF THE EASTERN ALEUTIANS FRIDAY AFTERNOON.
A LARGE 955 MB LOW IS EXPECTED TO BE NEAR 45N 166E FRI MORNING. THE
LOW SHOULD MAINTAIN ITS FULL INTENSITY AS IT MOVES TO 49N 175E BY
SATURDAY MORNING.
CONSIDERABLE UNCERTAINTY REGARDING THE 973 MB LOW NEAR 50N 155W FRI
MORNING. BEST ESTIMATE AT THIS TIME IS THAT IT WILL MOVE TO NEAR 52N
148W BY FRIDAY NIGHT THEN CONTINUE ON ON ITS NORTHEASTERLY TRACK.

.FORECAST...
NORTHERLY GAP WINDS WILL CONTINUE TO BLOW THROUGH PORTIONS OF THE
CHUGACH AND ALASKA RANGE TODAY BUT DIMINISH BY MIDNIGHT TONIGHT. HIGH
WIND WARNING FOR NORTHEAST PRINCE WILLIAM SOUND AND COPPER RIVER
DELTA PRESENTLY VERIFYING.
SCATTERED SNOW SHOWERS LINGERING ALONG THE ALEUTIANS ARE ASSOCIATED
WITH THE OLD FRONTAL BOUNDARY AND WILL GRADUALLY DISSIPATE.
EASTERLY FLOW ACROSS THE SOUTHERN BERING SEA WEAKENS THURSDAY NIGHT
AS THE LOW PRESENTLY NEAR ADAK WEAKENS AND MOVES OFF TO THE
SOUTHEAST. HOWEVER THE GRADIENT RETIGHTENS FRIDAY NIGHT IN RESPONSE
TO THE MAJOR LOW MOVING TOWARD SHEMYA. ALSO WITH THIS SYSTEM...SNOW
POSSIBLY MIXED WITH RAIN AT TIMES WILL MOVE INTO ALEUTIANS AGAIN
FRIDAY NIGHT.
THE 973 MB LOW MOVING INTO THE GULF OF ALASKA FRIDAY NIGHT WILL
SPREAD SNOW AND BLOWING SNOW ACROSS KODIAK ISLAND. THE KENAI
PENINSULA AND NORTH GULF COAST SHOULD ONLY BE GRAZED BY THIS SYSTEM.

.AER/ALU...WATCH/WARNING SUMMARY
PUBLIC...HIGH WIND 130 135
MARINE...GALE  121 129 130 132 138 150 155 172 175
         STORM 176
         HEAVY SPRAY 120 121 125 129 130 132 138 140 141 160 165
                     179 185
FIRE WEATHER...NONE

ASB FEB 08