Small Craft Advisory 435, NWS Anchorage, AK

AREA FORECAST DISCUSSION
SOUTHCENTRAL AND SOUTHWEST ALASKA
400 PM ADT SUN MAY 18 2008

.MODEL DISCUSSION...MODELS ARE IN GOOD AGREEMENT ON THE MAJOR
FEATURES INFLUENCING THE AREA THROUGH ABOUT 96 HOURS. GFS IS BEING
USED FOR BOTH THE EAST AND WEST DOMAINS FOR THIS AFTERNOONS
FORECASTS.

.ANALYSIS AND UPPER LEVELS...THE UPPER LEVEL PATTERN HAS A RIDGE OVER
THE WEST COAST OF NORTH AMERICA EXTENDING OVER THE ALCAN BORDER. THE
UPPER LEVEL TROUGH RESIDES OVER THE EASTERN BERING SEA AND OVER THE
EASTERN ALEUTIANS AND ALASKA PENINSULA. THIS PATTERN LOOKS TO REMAIN
LARGELY IN PLACE FOR THE NEXT FEW DAYS.
AT THE SURFACE A RIDGE IS OVER THE GULF OF ALASKA AND A WEAK LOW
SOUTHEAST OF THE PRIBILOF ISLANDS. THE LOW WILL DRIFT WESTWARD
THROUGH MONDAY AND THEN DISSIPATE MONDAY EVENING AS A NEW LOW
DEVELOPS SOUTH OF THE ALASKA PENINSULA MONDAY AND MOVES SOUTHWEST OF
COLD BAY EARLY TUESDAY.

.SHORT TERM FORECAST...ENOUGH HEATING IS OCCURRING OVER SOUTH CENTRAL
ALASKA AND THE COPPER RIVER BASIN TO KICK OFF A FEW SHOWERS OVER THE
MOUNTAINS. ATMOSPHERE IS STABLE ENOUGH THAT THEY ARE NOT EXPECTED TO
BE WIDESPREAD.
SOUTHWEST ALASKA IS A LITTLE COOLER BUT MORE UNSTABLE RESULTING IN
MORE SHOWERS. SLIGHT CHANCE OF A THUNDERSTORM IN THE KUSKOKWIM VALLEY
THIS AFTERNOON AND EVENING BUT LOOKS LIKE ANY THUNDERSTORMS WILL
PROBABLY BE NORTH OF THAT AREA.

.LONG TERM FORECAST...A THERMAL TROUGH MAY DEVELOP IN THE AFTERNOON
AND EVENINGS IN THE SUSITNA VALLEY AND THE EASTERN INTERIOR. THIS
WOULD RESULT IN GUSTY SOUTH TO SOUTHEAST WINDS THROUGH TURNAGAIN
ARM...THE KNIK VALLEY...AND ALONG THE COPPER RIVER. OTHER THAN THAT
LITTLE CHANGE IN THE FORECASTS ARE EXPECTED THROUGH MIDWEEK.

.AER/ALU...WATCH/WARNING SUMMARY
PUBLIC...NONE.
MARINE...NONE.
FIRE WEATHER...NONE.

MAY 08