Gale Warning 662, NWS Anchorage, AK

AREA FORECAST DISCUSSION
SOUTHCENTRAL AND SOUTHWEST ALASKA
400 PM AKDT FRI SEP 25 2009

.MODEL DISCUSSION...MODELS ARE CONSISTENT AND ARE HOLDING TOGETHER
WELL FOR THE FIRST THREE DAYS. GENERALLY WENT WITH A GFS SOLUTION IN
THE WEST AND NAM IN THE EAST.

.ANALYSIS AND UPPER LEVELS...THE LARGE LOW ALONG THE NORTH GULF COAST
IS THE EXTRA-TROPICAL REMNANTS OF TYPHOON CHOI WAN. THIS SYSTEM IS
NOT EVEN CLOSE TO BEING VERTICALLY STACKED WITH THE SURFACE LOW JUST
SOUTH OF PRINCE WILLIAM SOUND AND THE UPPER LEVEL LOW NEAR NUNIVAK
ISLAND. THIS UPPER LEVEL FLOW WILL HELP ESCORT THE LOW UP INTO THE
COPPER RIVER BASIN BY SATURDAY MORNING. ANOTHER SURFACE LOW IN THE
BERING SEA SOUTH OF THE PRIBILOFS IS TAPPING INTO THE COLD AIR ALOFT
STREAMING DOWN THE BACK SIDE OF THE UPPER LOW NEAR NUNIVAK ISLAND.
THIS LOW WILL HEAD NEARLY DUE EAST AD ACROSS THE SOUTHERN GULF
THROUGH THE WEEKEND. A RIDGE BOTH AT THE SURFACE AND ALOFT IS
ENTERING THE WESTERN BERING SEA AND WILL MOVE INTO THE CENTRAL BERING
SEA BY SATURDAY AFTERNOON. THIS WILL BRING WARMER TEMPERATURES TO
THESE AREAS WHILE MOST OF THE STATE WILL CONTINUE TO SEE DROPPING
TEMPERATURES AS THE COLD UPPER LEVEL TROUGH MOVES OVER THE MAINLAND
PART OF ALASKA TOMORROW.

.SHORT TERM FORECAST...THERE IS A LOW OF PRECIPITATION IN THE EASTERN
PART OF THE FORECAST AREA WITH RAIN AT THE LOWER LEVELS AND SNOW IN
THE MOUNTAINS. AS TEMPERATURES DROP OVERNIGHT AND COLDER AIR ALSO
ADVECTS INTO THE AREA THE FREEZING LEVEL WILL DROP OVER SOUTHWEST AND
SOUTH CENTRAL ALASKA. MOST AREAS NEAR SEA LEVEL WILL NOT SEE ANY SNOW
ACCUMULATIONS AS THE SNOWFALL WILL BE MINIMAL OVER WARM GROUND.
HOWEVER THE MOUNTAINS WILL SEE INCREASED SNOWFALL AMOUNTS TONIGHT
INTO SATURDAY.

.LONG TERM FORECAST...SHOWERS WILL PERSIST THROUGH SUNDAY IN SOUTH
CENTRAL ALASKA WHILE SOUTHWEST ALASKA WILL START TO FEEL THE EFFECTS
OF THE RIDGE MOVING OVER IT BY SUNDAY. MONDAY THIS RIDGE WILL MOVE TO
SOUTH CENTRAL ALASKA. A STRONG FRONT WILL MOVE INTO THE WESTERN
ALEUTIANS SATURDAY NIGHT AND BE FOLLOWED BY THE PARENT LOW SUNDAY
INTO MONDAY. THIS LOW WILL BE THE MAIN WEATHER FEATURE FOR MUCH OF
THE THE FORECAST AREA FOR THE FIRST PART OF NEXT WEEK.

.AER/ALU...WATCH/WARNING SUMMARY
PUBLIC...NONE.
MARINE...GALE 120 129 130 132 138 140 150 155 165 170 171 172 175
176.
FIRE WEATHER...NONE.

SEP 09