Small Craft Advisory 8, NWS Anchorage, AK

AREA FORECAST DISCUSSION
SOUTH CENTRAL AND SOUTHWEST ALASKA
200 PM AST TUE JAN 3 2006

.DISCUSSION...
THE MAIN ISSUE IN THE EAST DOMAIN TODAY IS THE FORECAST SOLUTION
DIVERGENCE WITH REGARD TO THE INCOMING STORM INTO THE SOUTHEAST GULF
OF ALASKA WEDNESDAY. AT THIS POINT THE FORECAST MODELS DIFFER ON
RESOLVING THE TRACK OF THIS LOW BEGINNING WEDNESDAY EVENING. THE ETA
PREFERS TO BRING THE LOW BACK TO THE WEST FASTER THAN BOTH THE GFS
AND UKMET. THIS SOLUTIONS SEEMS MORE REALISTIC TO WHAT TYPICALLY
OCCURS WITH THESE GULF LOWS. EXPECTING THE UPPER CENTER TO REMAIN
SOUTH OF THE GULF THE LIKELY TRACK WOULD BE TO THE WEST AND REMAIN
FURTHER SOUTH IN THE GULF THAN BOTH THE UKMET AND GFS SOLUTIONS. THIS
RESULTS IN A BIG DIFFERENCE IN THE FORECAST WIND IN THE GULF OFFSHORE
REGION AND THE SOUTHERN BOUNDARY TO MARINE AREA 120. WE EXPECT THE
TYPICAL NORTHEAST WIND ALONG THE NORTH GULF COAST AS THE ASSOCIATED
FRONT OF THIS STORM MOVES TO JUST OFF THE COAST WEDNESDAY MORNING.
THIS SHOULD ALSO RESULT IS STRONGER GAP WINDS ALONG THE CHUGACH
MOUNTAINS. ESPECIALLY OUT OF THE COPPER RIVER BASIN AS THE COLD DENSE
AIR WILL FORCE THROUGH THE MOUNTAIN GAPS. THE MOISTURE FROM THIS
STORM WILL REMAIN ALONG THE IMMEDIATE COAST AND WE DO NOT EXPECT MUCH
IF ANY PUSH INLAND WEDNESDAY. CLEARING CONDITIONS TONIGHT SHOULD
RESULT IN STRONG RADIATION COOLING, PARTICULARLY IN THE NORTHERN COOK
INLET TO THE SUSITNA VALLEY AND IN THE COPPER RIVER BASIN. BY
THURSDAY THE MOISTURE MAY PUSH INLAND INTO THE COPPER RIVER BASIN AND
ACROSS THE KENAI PENINSULA. THOUGH FORECAST CONFIDENCE AT THAT TIME
IS LOWER DUE TO MODEL INCONSISTENCY. FRIDAY SHOULD SEE THE MID AND
UPPER LEVEL LOW MOVE INTO THE WESTERN INTERIOR WHICH IN TURN SHOULD
BRING MORE CLOUDS AND POTENTIALLY PRECIPITATION INTO THE SOUTH
CENTRAL REGION AND ALONG THE ALASKA RANGE.

IN THE WEST THE ISSUE IS THE INCOMING STORM AND FRONT TO THE WESTERN
ALEUTIANS TONIGHT. STRONG WIND IN ADVANCE OF THE FRONT SHOULD HIT
WARNING LEVELS BRIEFLY IN THE MORNING HOURS THEN RAPIDLY DROP OFF
BEHIND THE FRONT IN THE EARLY AFTERNOON. THE DEVELOPMENT OF A LOW
ALONG THE FRONT NEAR ADAK LATE WEDNESDAY NIGHT WILL REDUCE THE WIND
IN ADVANCE OF THE FRONT AS IT PUSHES THROUGH THE CENTRAL AND EASTERN
ALEUTIANS.

THE LOW CURRENTLY IN THE GULF OF ALASKA COUPLED WITH THE RIDGE NOW
OVER THE CENTRAL ALEUTIANS AND BERING SEA ARE RESULTING IN NORTHERLY
FLOW OVER THE EASTERN BERING SEA AND THE ALASKA PENINSULA. TYPICAL
COLD ADVECTION TYPE SHOWER ACTIVITY IS PREVALENT ACROSS THESE AREAS
TODAY. TONIGHT THE RIDGE MOVES EAST REDUCING THE COLD ADVECTION
NORTHERLY FLOW AND WE SHOULD SEE A DECREASE IN THE SHOWER ACTIVITY AS
WELL AS DIMINISHING NORTHERLY WIND.

ALONG THE BERING SEA COAST A WEAK UPPER AND SURFACE LOW IS SPINNING
UP OVER THE KUSKOKWIM DELTA. THIS IS PRODUCING MAINLY SNOW SHOWERS
ACROSS THE REGION TODAY. THIS LOW IS NOT IDENTIFIED WELL BY ANY OF
THE MODELS. THE MOISTURE WITH THIS FEATURE FELL BETWEEN THE UPPER AIR
DATA POINTS THIS MORNING LEAVING THIS A BIG QUESTION MARK. SURFACED
BASED OBSERVATIONS THUS FAR TODAY INDICATE LITTLE IF ANY LOW AND MID
LEVEL MOISTURE MAKING IT DIFFICULT TO DETERMINE IF THIS WILL RESULT
IN SNOW SHOWERS IN THE KUSKOKWIM VALLEY THIS EVENING AND TONIGHT. AT
A MINIMUM WE EXPECT THE INCREASED CLOUD COVER TO MODERATE THE
OVERNIGHT LOWS.

.AER/ALU...WATCH/WARNING SUMMARY
PUBLIC...HIGH WIND WARNING ZONE 191.
MARINE...STORM 176 410. GALE 130 132 172 175 350 410. HEAVY FREEZING
SPRAY 179 185 410.
FIRE WEATHER...NONE.

SAM JAN 06