Small Craft Advisory 848, NWS Anchorage, AK

AREA FORECAST DISCUSSION
SOUTHCENTRAL AND SOUTHWEST ALASKA
400 PM AKST SUN NOV 2 2008

.MODEL DISCUSSION...THE MODELS ARE DOING VERY WELL WITH THE OVERALL
PATTERN. THIS HOLDS TRUE THROUGH MID WEEK WITH THE FIRST LARGE
DIFFERENCE COMING AROUND THURSDAY WITH A LOW DEVELOPING AND MOVING
INTO THE GULF OF ALASKA. THE GFS IS A BIT DEEPER AND FASTER WITH
MOVING THIS LOW INTO THE GULF THAN THE ECMWF. HOWEVER THE GFS AND
ECMWF BOT HAVE BEEN A BIT ERRATIC WITH BOTH THE STRENGTH AND PATH OF
THIS LOW. THEREFORE THE BEST THOUGHTS AT THIS TIME IS THAT THERE WILL
BE A LOW MOVING INTO THE LOW TOWARD THE END OF THE WEEK BUT IT SHOULD
BE WATCHED THE NEXT FEW DAYS TO SEE HOW IT DEVELOPS AND MOVES.

THE ONLY DETAIL IN THE SHORT TERM THAT BEARS MENTIONING IS WITH THE
LOW MOVING UP ALONG THE NORTH GULF COAST. THE NAM PRECIPITATION FIELD
IS A BIT TOO FAR TO THE EAST. THE GFS HAS IT FARTHER WEST AND THIS
LOOKS MUCH BETTER WITH WHAT HAS BEEN OCCURRING AND WHAT IS FORECAST.

.ANALYSIS AND UPPER LEVELS...THE UPPER LEVEL PATTERN HAS A RIDGE OVER
THE ARCTIC OCEAN EXTENDING SOUTHWARD OVER SOUTH CENTRAL ALASKA. THERE
IS A SHORT WAVE MOVING OVER THE BRISTOL BAY AREA AND THE KUSKOKWIM
VALLEY WITH THE JET STREAM REMAINING SOUTH OF THE FORECAST AREA.
AT THE SURFACE THERE IS A LOW ALONG THE NORTHERN GULF OF ALASKA THAT
WILL BE SLOWLY MOVING WESTWARD. THIS SYSTEM IS BRINGING CLOUDS AND
SNOW INTO THE COPPER RIVER BASIN AND WILL CONTINUE TO BRING SOME
LIGHT SNOWFALL INTO THE COPPER RIVER BASIN THROUGH MONDAY. THIS LOW
IS ALSO HELPING TO PRODUCE GUSTY OUTFLOW WINDS THROUGH CHANNELED
TERRAIN...ESPECIALLY ALONG THE COAST.
A WEAK LOW EAST OF THE PRIBILOF ISLANDS WILL DISSIPATE AS IT REACHES
THE ALASKA PENINSULA TONIGHT.
THE MODERATE LOW SOUTH OF THE CENTRAL ALEUTIAN ISLANDS WILL REMAIN
SOUTH OF THE FORECAST AREA.

.SHORT TERM FORECAST...SNOW WILL PERSIST IN THE COPPER RIVER BASIN
THROUGH MONDAY AS THE SITUATION IS GOOD FOR OVERRUNNING. THERE IS NOT
AN ABUNDANCE OF MOISTURE WITH THIS SYSTEM SO SNOW AMOUNTS ARE NOT
EXPECTED TO BE VERY IMPRESSIVE.
GUSTY OUTFLOW WINDS ALONG THE NORTH GULF COAST WILL CONTINUE THROUGH
TONIGHT AND THEN EASE SOME MONDAY AS THE PRESSURE GRADIENT DECREASES.

SHOWER ACTIVITY WILL PERSIST IN THE BERING SEA, ALASKA PENINSULA AND
EASTERN ALEUTIAN ISLANDS AS THE FLOW REMAINS MOSTLY FROM THE
NORTHWEST. THERE WILL BE A LITTLE MORE PRECIPITATION OVER THE ALASKA
PENINSULA TONIGHT AS THE LOW IN THE EASTERN BERING SEA MOVES TO THAT
AREA DISSIPATES TONIGHT.

.LONG TERM FORECAST...FORECASTS THROUGH MID WEEK LOOK GOOD. MODEL
CONSISTENCY AND A PATTERN THAT IS NOT CHANGING RAPIDLY GIVES A HIGH
CONFIDENCE IN THE FORECAST THROUGH THEN.
THINGS BECOME LESS CERTAIN STARTING AROUND THURSDAY IN THE GULF OF
ALASKA REGION DUE UNCERTAINTIES WITH A LOW MOVING INTO THE AREA.

.AER/ALU...WATCH/WARNING SUMMARY
PUBLIC...NONE.
MARINE...GALE 130.
FIRE WEATHER...NONE.

NOV 08