Small Craft Advisory 543, NWS Anchorage, AK

AREA FORECAST DISCUSSION
SOUTHCENTRAL AND SOUTHWEST ALASKA
400 PM AKDT THU JUL 10 2008

.MODEL DISCUSSION...MODELS SHOWING SAME GENERAL PICTURE BUT THERE IS
ENOUGH DIFFERENCES TO AFFECT THE FORECAST. THE BEST PERFORMER AS FAR
A CONSISTENT BETWEEN RUNS IS THE GFS. IT ALSO HAS A VERY REASONABLE
SOLUTION SO IT WILL BE THE ONE MOST HEAVILY RELIED ON OVERALL. WHERE
THE NAM IS DOING BETTER IN THE SHORT TERM IS IN THE SOUTHERN GULF OF
ALASKA. THE LOW MOVING INTO THE SOUTH CENTRAL GULF IS REFLECTED WELL
IN THE NAM BUT ALMOST IGNORED BY THE GFS. BOTH MODELS HAVE IT HEADING
INTO THE EASTERN GULF SO THE ONLY AREA IN THE ANCHORAGE FORECAST AREA
THAT WILL BE AFFECTED IS THE MARINE OFFSHORE AREA. OTHER THAN THAT
THE GFS SOLUTION LOOKS TO BE BETTER.

.ANALYSIS AND UPPER LEVELS...AN UPPER LEVEL RIDGE REMAINS OVER SOUTH
CENTRAL AND EASTERN ALASKA. THE MAIN UPPER LEVEL LOW IS CENTERED OVER
EASTERN RUSSIA WITH A SHARP TROUGH DESCENDING OUT OF IT INTO
SOUTHWEST ALASKA. THIS TROUGH WILL WEAKEN AND DISSIPATE AS IT RUNS
INTO THE RIDGE...WHICH WILL REMAIN MOSTLY IN PLACE THROUGH SATURDAY.
THE UPPER LEVEL LOW WILL REMAIN CENTERED IN EASTERN RUSSIA INTO NEXT
WEEK KEEPING GENERALLY SOUTHWEST FLOW OVER THE BERING SEA AND
SOUTHWEST ALASKA THROUGH THEN.

.SHORT TERM FORECAST...CONVECTION WILL BE CONFINED TO NEAR THE ALASKA
RANGE AND TO THE NORTHERN KUSKOKWIM VALLEY THIS AFTERNOON AND
EVENING. THIS WILL BE THE SAME AREA FOR FRIDAY AS WELL BUT THE
ATMOSPHERE WILL BE A LITTLE MORE STABLE TOMORROW.
SOUTHWEST ALASKA WILL SE SHOWERS THROUGH THE NIGHT AS THE UPPER LEVEL
TROUGH WEAKENS OVER THAT AREA.

.LONG TERM FORECAST...UPPER LEVEL PATTERN REMAINS CONDUCIVE TO A
SERIES OF LOW PRESSURE SYSTEMS MIGRATING ACROSS THE BERING BUT NOT
MAKING IT INLAND. SIMILAR FOR THE GULF OF ALASKA WITH A RIDGE NOSING
ALONG THE NORTH GULF COAST. COASTAL REGIONS WILL EXPERIENCE PERIODS
OF LIGHT RAIN AND FOG. INLAND AREAS SHOULD SEE A RETURN TO TYPICAL
SUMMERTIME SHOWERS EARLY NEXT WEEK.

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

JUL 08