Small Craft Advisory 170, NWS Anchorage, AK

AREA FORECAST DISCUSSION
SOUTHCENTRAL AND SOUTHWEST ALASKA
500 AM AST WED FEB 22 2006

.DISCUSSION...
MODELS IN GENERALLY GOOD AGREEMENT. GFS MODEL OF CHOICE WEST OF
160W. UKMET OR ETA SOLUTION PREFERRED EAST OF 160W.

UPPER LEVEL PATTERN...
BROAD ZONAL FLOW AT 500 MB CONTINUES THROUGH THIS EVENING. LONG WAVE
TROF ALOFT DEVELOPS OVER WESTERN ALASKA WED EVENING...THEN
STRENGTHENS AND MOVES EASTWARD. TROF IS PROGGED TO EXTEND FROM
BETTLES TO KODIAK CITY BY THU AFTERNOON. TROF FURTHER
AMPLIFIES...BECOMING A CLOSED H523 LOW JUST SOUTH OF THE GULF OF
ALASKA NEAR FRI AFTERNOON.

SFC FEATURES ALU DOMAIN...
HIGH PRESSURE WILL PERSIST ACROSS THE ALEUTIAN CHAIN. AREAS OF LOW
CLOUDS AND DENSE FOG LATE NIGHT AND MORNING HOURS.
A 1014 MB LOW 270 NM WEST OF ST MATTHEW ISLAND WILL MOVE INLAND
NEAR EMMONAK WED EVENING WITH LITTLE CHANGE IN INTENSITY. THIS WILL
BE MAINLY A WIND EVENT FOR THE BERING SEA. LITTLE PRECIPITATION
EXPECTED. HOWEVER...SIGNIFICANT UPSLOPE ALONG THE WESTERN SLOPES OF
THE ALASKA RANGE TONIGHT IS EXPECTED TO HELP YIELD OVER 3 INCHES OF
FRESH SNOW AT HIGHER ELEVATIONS. THE LOW IS PROGGED TO DISSIPATE
OVER THE EASTERN KUSKOKWIM VALLEY ON THURSDAY.

SFC FEATURES AER DOMAIN...
NORTHWESTERLY FLOW WILL PERSIST ACROSS SOUTHERN ALASKA AND THE GULF
THROUGH WED NIGHT.
A 1023 MB LOW DEVELOPS NEAR HOMER THU MORNING AND STRENGTHENS TO
1017 IN THE CENTRAL GULF OF ALASKA LATE THU NIGHT. OCCASIONAL LIGHT
SNOW DEVELOPS ACROSS SOUTHCENTRAL ALASKA AND NORTH GULF COAST THU
MORNING AND CONTINUES THROUGH THU NIGHT.

COMING ATTRACTIONS...
A LARGE COMPLEX LOW PRESSURE SYSTEM IS PROGGED TO BE OVER THE
RUSSIAN FAR EAST THU EVENING. GALES DEVELOPING IN THE WESTERN BERING
AS EARLY AS LATE THU NIGHT. UPPER LEVEL FLOW IS SUPPORTIVE OF
STEERING THIS LOW COMPLEX NORTHWESTWARD...INTO THE CHUCKCHI SEA AND
NORTHERN ALASKA SUNDAY NIGHT AND MONDAY.

.AER/ALU...WATCH/WARNING SUMMARY
PUBLIC...NONE.
MARINE...GALES 120 150 155 176 185
         HEAVY FREEZING SPRAY 180 185
FIRE WEATHER...NONE.

ASB FEB 06