Small Craft Advisory 273, NWS Anchorage, AK

AREA FORECAST DISCUSSION
SOUTHCENTRAL AND SOUTHWEST ALASKA
400 PM AKDT THU MAR 26 2009

.MODEL DISCUSSION...NAM MODEL IS DOING BETTER WITH THE DETAILS OF THE
LOW IN THE NORTHERN GULF. MODELS ARE OTHERWISE IN GOOD AGREEMENT
THROUGH SATURDAY AFTERNOON. AFTER THAT THERE IS SOME DISAGREEMENT TOT
THE ACTUAL TRACK OF A STRONG LOW THAT WILL MOVE NEAR THE TIP OF THE
ALASKA PENINSULA. DIFFERENCES ARE NOT EARTH SHATTERING THOUGH AND WE
ARE GOING MOSTLY WITH THE GFS AS GUIDANCE.

.ANALYSIS AND UPPER LEVELS...UPPER LEVEL TROUGH IS SITUATED OVER
WESTERN ALASKA AND EXTENDING OVER THE PRIBILOF ISLANDS. THE POSITION
OF THIS UPPER LEVEL TROUGH WILL REMAIN MOSTLY UNCHANGED INTO THE
WEEKEND. AT THE SURFACE THE LOW CENTER IS NEAR MIDDLETON ISLAND AND
WILL MOVE OVER THE EASTERN KENAI PENINSULA TONIGHT AND THEN SLOWLY
MOVE TO THE COPPER RIVER BASIN FRIDAY AFTERNOON.
THE 250 MB JET IS RUNNING FROM THE SOUTHWEST AND IS REMAINING SOUTH
OF THE AREA RIGHT NOW. IT WILL MOVE INTO THE GULF ON SATURDAY AS IT
STRENGTHENS A LOW THAT WILL MOVE NEAR THE ALASKA PENINSULA SATURDAY
AND SATURDAY NIGHT.

.SHORT TERM FORECAST...BLIZZARD CONDITIONS ALONG THE ALASKA PENINSULA
SHOULD END BY EARLY THIS EVENING THOUGH THERE WILL BE SOME LOCALLY
REDUCED VISIBILITIES FROM BLOWING SNOW THROUGH THE NIGHT...BUT NOT AS
BAD AS IT HAS BEEN.
THE LOW NEAR THE NORTH GULF COAST IS KEEPING THE BARRIER JET IN TACK
THIS AFTERNOON. IT SHOULD DIMINISH THIS EVENING AND THEN DISSIPATE AS
THE LOW MOVES INTO THE EASTERN KENAI PENINSULA TONIGHT. PRECIPITATION
SHOULD TURN BACK TO ALL SNOW AS THIS SYSTEM OCCLUDES AND THE WARM AIR
HEADS SOUTH OF THE AREA. THERE IS AN INCREASED POTENTIAL FOR SNOW IN
THE ANCHORAGE AREA LATE TONIGHT THROUGH FRIDAY NIGHT WITH THE LATEST
TRACK OF THIS LOW.

.LONG TERM FORECAST...IT APPEARS AS THOUGH THE PATTERN OF THE NEXT
THREE DAYS REPEATS...WITH ANOTHER STRONG LOW MOVING INTO THE NORTHERN
GULF ON SUNDAY BEFORE EVENTUALLY MOVING ONSHORE AND INTO THE COPPER
RIVER BASIN SOMETIME THE FIRST HALF OF NEXT WEEK.  THE LACK OF HIGH
PRESSURE TO THE NORTH AND EAST WITH THIS SYSTEM MAY HELP TO KEEP
WINDS FROM BECOMING QUITE AS STRONG IN THE NORTHERN GULF WITH THIS
NEXT SYSTEM AS THEY WERE WITH THIS ONE.

.AER/ALU...WATCH/WARNING SUMMARY
PUBLIC...BLIZZARD 181.
MARINE...GALE 120 125 150 155 170 172 175 176.
         HEAVY FREEZING SPRAY 155 165 179.
FIRE WEATHER...NONE.

MAR 09