Small Craft Advisory 342, NWS Anchorage, AK

AREA FORECAST DISCUSSION
SOUTHCENTRAL AND SOUTHWEST ALASKA
500 AM ADT SAT APR 15 2006

.DISCUSSION...

UPPER LEVEL TROUGH CENTERED OVER THE EASTERN GULF THIS MORNING...
ENCOMPASSING MOST OF MAINLAND ALASKA AND WESTERN CANADA. AN EQUALLY
MASSIVE RIDGE RESIDES OVER THE BERING. AT THE SURFACE AN ELONGATED
TROUGH EXTENDS FROM THE NORTH GULF COAST TOWARD THE PACIFIC
NORTHWEST...WITH A RIDGE OVER THE EASTERN BERING AND A LOW JUST EAST
OF THE KAMCHATKA PENINSULA.

MODELS AGREE THAT BY SUN NIGHT THE KAMCHATKA LOW AND A TRIPLE POINT
LOW WILL REACH THE AKPEN. THESE LOWS MERGE AND THE NEW LOW MOVES INTO
THE GULF. BY WED AFTERNOON IT WEAKENS AND ELONGATES INTO A BROAD
TROUGH OF LOW PRESSURE. THE WEATHER FRONT ASSOCIATED WITH THE
KAMCHATKA LOW CONSOLIDATES THIS AFTERNOON OVER THE PRIBILOFS AND
EASTERN ALEUTIANS...REACHES BRISTOL BAY TONIGHT AND THEN MOVES ACROSS
THE GULF BY SUN NIGHT. THE NEXT NORTH PACIFIC FRONT MOVES ACROSS THE
BERING TUE THROUGH THU.

IN THE EAST...GENERALLY DRY CONDITIONS PERSIST SOUTH AND EAST OF THE
AK RANGE THROUGH SUN MORNING. ONSHORE FLOW AND PRECIP RELATED TO THE
FRONT BEGINS OVER KODIAK SUN AFTERNOON AND AFFECTS THE ENTIRE GULF
COAST SUN NIGHT. DOWNSLOPING SHOULD LIMIT PRECIP OVER ANCHORAGE AND
DOWNWIND SIDES OF MOUNTAIN RANGES. SIGNIFICANT TURNAGAIN ARM AND
NORTH GULF COAST WINDS ARE EXPECTED IN THE SAME PERIOD...DIMINISHING
MON MORNING AS THE FRONT PASSES INTO THE EASTERN GULF. SHOWERS OVER
THE ENTIRE AREA WILL PERSIST THROUGH WED...WITH A SHOT INLAND WED
NIGHT INTO THU AS AN UPPER LEVEL TROUGH MOVES ACROSS THE AK RANGE.

OVER SOUTHWEST ALASKA...CLEAR CONDITIONS WILL GIVE WAY TO INCREASING
CLOUDS TONIGHT AS THE FRONT APPROACHES. EXPECT INCREASING WIND AND
SNOWFALL SUN...ESPECIALLY ALONG THE COAST. BY SUN NIGHT THE ENTIRE
AREA WILL BE UNDER BROAD CYCLONIC FLOW WITH CORRESPONDING SNOW SHOWER
ACTIVITY THROUGH MON. A DRYING TREND THEN BEGINS AND PERSISTS INTO
THU.

OUT WEST...INCREASING SOUTH FLOW WITH SNOW AND THEN RAIN OVER THE
EASTERN ALEUTIANS SETS UP THIS AFTERNOON AND MOVES TOWARD BRISTOL BAY
TONIGHT. WEST WIND BEHIND THE FRONT INCREASES IN INTENSITY TONIGHT
OVER THE WESTERN ALEUTIANS AND REACHES THE EASTERN ALEUTIANS SUN.
LOOKS AS IF THESE WINDS MAY REACH HIGH WIND WARNING CRITERIA. THE
WIND WILL SLOWLY DIMINISH SUN NIGHT BELOW WARNING LEVELS AND CONTINUE
TO SLOWLY DIMINISH INTO TUE. EXPECT ANOTHER ROUND OF PRECIP TO SPREAD
ACROSS THE CHAIN TUE THROUGH THU AS THE NEXT FRONT MOVES ACROSS THE
AREA.

.AER/ALU...WATCH/WARNING SUMMARY
PUBLIC...HIGH WIND WATCH 185 187 191
MARINE...STORMS 170 172 175 176
         GALES 130 132 150 155 160 165 171 179 180 185
         HEAVY FREEZING SPRAY 160 185
FIRE WEATHER...NONE

DS APR 06