Small Craft Advisory 253, NWS Anchorage, AK

AREA FORECAST DISCUSSION
SOUTHCENTRAL AND SOUTHWEST ALASKA
200 PM AST FRI MAR 17 2006

.DISCUSSION...THE LARGE LOW IN THE BERING SEA THAT HAS DOMINATED THE
WEATHER MAP THE LAST FEW DAYS IS STILL THE PROMINENT FEATURE THIS
AFTERNOON. HOWEVER THIS LOW WILL BE WEAKENING RAPIDLY OVER THE NEXT
DAY AND WILL DISSIPATE NORTH OF ST PAUL ISLAND TOMORROW EVENING. A
NEW LOW WILL MOVE INTO THE BERING SEA BEHIND IT BUT IT WILL NOT BE
NEARLY AS STRONG AS THIS ONE HAS BEEN.

A RELATIVELY WEAK FRONT THAT EXTENDS OUT OF THE BERING SEA LOW
STRETCHES FROM THE KUSKOKWIM DELTA INT SOUTHERN COOK INLET AND THEN
INTO THE GULF OF ALASKA. THIS FRONT IS SLOWLY MOVING NORTHWARD.

THE JET STREAM IS VISIBLE ON THE SATELLITE PICTURE ORIGINATING IN THE
SUBTROPICS AND EXTENDING TO NEAR KODIAK ISLANDS AS IT RIDES ALONG THE
WESTERN SIDE OF A RIDGE. A DEVELOPING LOW IS EVIDENT ALONG THIS JET
NEAR 35N 160W. THIS LOW WILL MOVE RAPIDLY NORTHWARD IN THE JET AND
INTO THE GULF OF ALASKA SATURDAY. THIS LOW WILL INTENSIFY AS IT DOES
SO AND WILL BECOME THE MAJOR WEATHER MAKER IN SOUTHERN ALASKA THIS
WEEKEND.

THE MODELS HAVE NOT BEEN AS CONSISTENT AS ONE WOULD LIKE ON THE
APPROACH OF THIS STROM. GFS AND UKMET ARE RELATIVELY WELL ALIGNED
WITH EACH OTHER FROM THE 12Z RUN. HOWEVER THE GFS SOLUTION HAS
CHANGED OVER THE LAST FEW RUNS AND THE NAM HAS BEEN MORE INTERNALLY
CONSISTENT. NAM HAS STRONGER WINDS ALONG THE NORTH GULF COAST WITH
THE LOW BEING FURTHER WEST. EITHER SOLUTION BODES WELL FOR THE
HURRICANE FORCE WINDS TO DEVELOP IN THE BARRIER JET THAT WILL FORM
ALONG THE NORTH GULF COAST. STRONG WINDS WILL DEVELOP OUT OF THE
MATANUSKA RIVER AND THROUGH TURNAGAIN ARM AS WELL AS THIS SYSTEM
MOVES INTO THE NORTHERN GULF OF ALASKA.
ANOTHER BIG QUESTION IS THE COMBINATION ON WIND AND SNOW AND THE
RESULTING REDUCTIONS IN VISIBILITIES THAT MAY OCCUR. THE BLOWING SNOW
ADVISORY IN KODIAK OVERNIGHT STILL LOOKS GOOD. BIGGER QUESTION IS
WHETHER THERE WILL BE BLIZZARD CONDITIONS IN THE EASTERN KENAI
PENINSULA. EASTERN TURNAGAIN ARM LOOKS LIKE THE MOST LIKELY PLACE FOR
THIS TO OCCUR. DUE TO THE MODEL UNCERTAINTY AND THE EFFECT A SMALL
CHANGE IN MODEL SOLUTION WILL HAVE ON THE EVENT WE ARE GOING WITH A
BLIZZARD WATCH IN ZONE 125 TO COVER THIS POSSIBILITY.

.AER/ALU...WATCH/WARNING SUMMARY
PUBLIC...BLIZZARD WATCH 125.
MARINE...GALE 121 125 129 132 138 140 155 165 170 172 175 176 179 185
         STORM 130
         HURRICANE FORCE 120
         HEAVY FREEZING SPRAY 121 140
FIRE WEATHER...NONE.

EZ MAR 06