Small Craft Advisory 1004, NWS Anchorage, AK

AREA FORECAST DISCUSSION
SOUTH CENTRAL AND SOUTHWEST ALASKA
500 PM AKST TUE DEC 16 2008

.MODEL DISCUSSION...
MODELS ARE IN GOOD AGREEMENT OUT THROUGH 96 HOURS OR SAT MORNING.
THE MODELS FROM YESTERDAYS RUNS DIFFERED OVER THE WEEKEND WITH THE
GFS MOVING AN ALEUTIAN LOW TO KODIAK AND THEN SOUTHEAST TOWARD THE
QUEEN CHARLOTTES.  THE ECMWF TRACKED THIS LOW FARTHER SOUTH AND
FASTER. THE MODELS ARE CLOSER TO THE GFS SOLUTION TODAY BUT THE ECMWF
STILL IS SHOWING A TENDENCY TO UNDERCUT THE GFS TRACK TO THE SOUTH
AND BE MORE AGGRESSIVE IN FORMING A TRIPLE POINT LOW SOUTHEAST OF THE
CHARLOTTES SAT.

.ANALYSIS AND UPPER LEVELS...
UPPER AIR...A VERY STABLE WAVE NUMBER 2 PATTERN IS IN PLACE OVER THE
ARCTIC AND SUB ARCTIC.  THE TRANSLATION IS A LONG WAVE RIDGE OF HIGH
PRESSURE IS FIXED IN PLACE OVER ALASKA.  THIS RIDGE IS EXPECTED TO
PERSIST THROUGH NEXT WEEK. A WEAKENING UPPER LOW IS FORECAST TO MOVE
ACROSS THE ALEUTIANS TODAY THROUGH FRIDAY THEN MOVE THROUGH THE RIDGE
IN THE TO THE NORTHERN GULF SATURDAY THEN TURN SOUTHEAST TOWARD THE
WEST COAST SUNDAY. ANOTHER SHORT WAVE TROUGH IS EXPECTED TO CROSS THE
NORTHERN BERING SUNDAY AND MOVE OVER CENTRAL ALASKA ON MONDAY.

SURFACE...A WEAK LOW WILL MOVE FROM SOUTH OF UNALASKA TO THE BERING
STRAIT BY WED NIGHT.  ANOTHER LOW NEAR ADAK WILL STRENGTHEN AND MOVE
TO UNALASKA BY THU AFTERNOON AND THEN TO JUST EAST OF KODIAK ISLAND
BY LATE FRI.  A MODERATELY STRONG LOW WILL MOVE FROM NEAR JAPAN TO
THE EXTREME WESTERN BERING BY FRI.

.SHORT TERM FORECAST...
AREAS OF FOG WILL FORM AGAIN TONIGHT FROM THE ANCHORAGE BOWL AND DOWN
ALONG COOK INLET. ELSEWHERE CLEAR SKIES WILL CONTINUE. AS THE HIGH
SHIFTS TO THE EAST AND THE UPPER FLOW BECOMES SOUTHWESTERLY CLOUDS
WILL INCREASE OVER SOUTH CENTRAL WITH A CHANCE OF SOME PRECIPITATION
BY WEDNESDAY. OTHERWISE EXPECT MOSTLY DRY CONDITIONS AND TEMPERATURES
WARMING SOME.

SOUTHWEST...
WARM AIR AND MOISTURE WILL MOVE UP ALONG THE WEST COAST AND
BRISTOL BAY TONIGHT. PRECIPITATION SHOULD BE A RAIN AND SNOW MIX
ALONG THE COAST AND ALL SNOW INLAND. IN THE KUSKOKWIM VALLEY
EXPECT INCREASING CLOUDS THIS EVENING A CHANCE OF SNOW
TONIGHT AND SNOW LIKELY WEDNESDAY.

ALEUTIANS/ALASKA PENINSULA/BERING SEA...
EXPECT RAIN TO CONTINUE OVER THE ALASKA PENINSULA AND EASTERN
ALEUTIANS AND MOVE NORTH OVER THE PRIBILOFS.  RAIN WILL MOVE FROM THE
CENTRAL TO EASTERN ALEUTIANS TONIGHT THROUGH THURSDAY WITH THE NEXT
LOW. SNOW SHOWERS WILL PERSIST OVER THE WESTERN ALEUTIANS WITH THE
COLD AIR DROPPING DOWN ON THE WEST SIDE OF THE LOW.

.LONG TERM FORECAST...
LOW PRESSURE MOVING ALONG THE EASTERN ALEUTIANS/ALASKA PENINSULA ON
THURSDAY WILL MOVE JUST EAST OF KODIAK ISLAND BY FRIDAY NIGHT THEN
SLOWLY DISSIPATE AND REFORM AS A DEVELOPING TRIPLE POINT LOW OFF
SOUTHEAST ALASKA SAT NIGHT. HIGH PRESSURE WILL BUILD BACK INTO THE
GULF ON SUNDAY. A LOW WILL MOVE TO THE WESTERN BERING FRIDAY AND A
STRONG FRONT WILL MOVE TO THE WESTERN BERING SEA FRIDAY. THE REMAINS
OF THIS LOW WILL MOVE ACROSS THE NORTHERN BERING OVER THE WEEKEND AND
INTO THE CHUKCHI SEA MONDAY.

.AER/ALU...WATCH/WARNING SUMMARY
PUBLIC...NONE
MARINE...GALE 160 165 172 175 176 179 180 411 412 413 414
FIRE WEATHER...NONE

RHH DEC 08