Small Craft Advisory 1111, NWS Anchorage, AK

AREA FORECAST DISCUSSION
SOUTHCENTRAL AND SOUTHWEST ALASKA
300 PM AST FRI DEC 1 2006

.DISCUSSION...THE STORM SYSTEM THAT HAS BROUGHT SNOWFALL TO MUCH OF
SOUTH CENTRAL ALASKA IS HEADING EASTWARD. THE UPPER LEVEL TROUGH HAS
PASSED JUST EAST OF THE COOK INLET AREA EARLY IN THE AFTERNOON AND
HAS SHUT OFF MOST OF THE SNOW IN THE COOK INLET AND SUSITNA AREAS.
SNOW WILL CONTINUE IN THE COPPER RIVER BASIN UNTIL THEIS TROUGH
PASSES THROUGH TONIGHT.

THE SURFACE LOW IS A WEAK 1013 MB LOW AND CENTERED JUST SOUTH OF
PRINCE WILLIAM SOUND. THIS LOW WILL REMAIN NEARLY STATIONARY THROUGH
TONIGHT WHEN IT WILL DISSIPATE AS ALL THE UPPER LEVEL SUPPORT HEADS
INTO CANADA. A 1028 MB HIGH IS BUILDING INTO SOUTHWESTERN ALASKA
TODAY AND WILL LINK UP WITH A BUILDING RIDGE IN THE EASTERN INTERIOR.
THIS WILL HELP CONTINUE A FAIRLY STRONG PRESSURE GRADIENT OVER SOUTH
CENTRAL ALASKA FOR THE NEXT DAY ESPECIALLY ALONG THE GULF OF ALASKA
COAST. THE NEXT LOW FOR THE GULF OF ALASKA AREA WILL ARRIVE SATURDAY
NIGHT. THIS ONE DOES NOT HAVE A LOT OF UPPER SUPPORT BUT THERE IS
SOME WARM AIR ENTRAINED IN IT SO EXPECT A LITTLE WARMER TEMPERATURES
WITH THAT SYSTEM.

IN THE WESTERN PART OF THE FORECAST AREA...THE MAIN FEATURE IS A 960
MB LOW JUST SOUTH OF AMCHITKA ISLAND THIS AFTERNOON. THIS LOW WILL
REMAIN NEAR 960 MB THROUGH THE NIGT AND THEN SLOWLY WEAKEN AS IT
MOVES INTO EASTERN RUSSIA SATURDAY NIGHT. THERE IS A VERY TIGHT
PRESSURE GRADIENT AROUND THIS LOW AS WELL AS STRONG TEMPERATURE
ADVECTION AT 850 MB. A HIGH WIND WARNING IS IN EFFECT FOR THE CENTRAL
AND WESTERN ALEUTIAN ISLANDS DUE TO THIS LOW.

ALONG THE SOUTHWEST COAST OF MAINLAND ALASKA...THE RIDGE OF HIGH
PRESSURE WILL KEEP THE ATMOSPHERE RATHER DRY. THE PRESSURE GRADIENT
DUE TO THE ALEUTIAN STORM WILL TIGHTEN UP AND PROBABLY CAUSE ENOUGH
MIXING TO KEEP FOG TO A MINIMUM IN THIS AREA.

MODELS IN DECENT AGREEMENT. PREFER THE GFS SOLUTION TO THE GULF OF
ALASKA LOW THAT MOVES IN SATURDAY NIGHT.

.AER/ALU...WATCH/WARNING SUMMARY
PUBLIC...HIGH WIND WARNING 187 191.
MARINE...GALE 120 130 132 170 171 179 180 185.
         STORM 172 176.
         HURRICANE FORCE 175.
FIRE WEATHER...NONE.

EZ DEC 06