Small Craft Advisory 1182, NWS Anchorage, AK

AREA FORECAST DISCUSSION
SOUTHCENTRAL AND SOUTHWEST ALASKA
500 AM AST THU DEC 21 2006

.DISCUSSION...

...SUMMARY...
MAIN WEATHER PLAYER FOR THE FORECAST IS LOW PRESSURE SYSTEMS
CONTINUING TO TRAIN FROM SOUTH TO NORTH THROUGH THE GULF AND INTO
SOUTHCENTRAL...KEEPING THE SNOW COMING. NORTHWEST FLOW WITH EMBEDDED
WEAK LOW PRESSURES CONTINUES FOR THE BERING AND ALEUTIANS...WITH
OCCASIONAL SNOW SHOWERS...HEAVY AT TIMES. NOT MUCH CHANGE IN THIS
WEATHER PATTERN THROUGH THE WEEKEND.

...MODELS...
MODELS OVERALL ARE IN DECENT AGREEMENT TONIGHT. MAIN FEATURE OF
CONCERN WITH THE MODELS IS THE TRACK OF LOWS THROUGH THE GULF AND
INTO SOUTHCENTRAL. THE LOW PRESSURE JUST SOUTH OF SEWARD THIS MORNING
APPEARS TO BE TAKING A TRACK CLOSER TO THE GFS THAN THE
NAM/WRF...WITH THE LOW MOVING OVER THE EASTERN KENAI BY MIDDAY.
MODELS AGREE QUITE WELL ON THE TRACK OF THE NEXT STRONG GULF LOW TO
MOVE ONSHORE SATURDAY.

...SOUTHCENTRAL FORECAST SOUTH AND EAST OF THE ALASKA RANGE...
A WEAK LOW JUST SOUTH OF SEWARD IS ACTUALLY IMPACTING SOUTHCENTRAL
QUITE STRONGLY TODAY...WITH YET MORE SNOWFALL. A BAND OF MODERATE TO
HEAVY SNOW HAS SET UP EARLY THURSDAY MORNING FROM SEWARD TO PORTAGE
TO ANCHORAGE TO WILLOW. SNOWFALL RATES OF AROUND 3 INCHES PER HOUR
HAVE OCCURRED AT PORTAGE. SHOWERS...HEAVY AT TIMES...ARE POSITIONED
EAST OF THE LOW FROM THE NORTH GULF INTO PRINCE WILLIAM SOUND. SOME
SHOWERS HAVE EVEN HAD A BIT OF LIGHTNING. HOW THINGS EXACTLY PLAY OUT
OVER SOUTHCENTRAL TODAY WILL BE A BIT TOO COMPLICATED TO MENTION IN
THIS DISCUSSION...BUT BASICALLY...SNOW OR SNOW SHOWERS ARE EXPECTED
TO CONTINUE TODAY OVER MOST AREAS AS THE LOW MOVES INLAND. ALL OF
THIS IS ON TOP OF SIGNIFICANT SNOWFALL FROM THE LAST STORM WHICH ONLY
JUST ENDED. AS THE LOW MOVES INLAND AND DISSIPATES...SNOW WILL TAPER
OFF TONIGHT OVER SOUTHCENTRAL. HOWEVER...YET ANOTHER LOW PRESSURE
WILL RACE NORTH UP THE GULF...BRINGING MORE SNOW TO SOUTHCENTRAL
BEGINNING FRIDAY AND LASTING INTO SATURDAY. THE MODELS ARE HINTING AT
A CHANGE IN THE WEATHER PATTERN BEGINNING SUNDAY...WHICH WOULD DRIVE
THE NEVER ENDING LOWS FURTHER EAST MORE TOWARDS THE PANHANDLE...AND
BRING COLD DRIER OFFSHORE FLOW INTO SOUTHCENTRAL.

...SOUTHWEST MAINLAND FORECAST...
THE SOUTHWEST MAINLAND WILL CONTINUE TO HAVE THE CALMEST WEATHER OF
THE STATE...AS THEY WILL REMAIN UNDER A WEAK RIDGE OF HIGH PRESSURE.
STILL...AREAS OF LOW CLOUDS AND LIGHT SNOW WILL CONTINUE OVER THE
NEXT FEW DAYS.

...BERING/ALEUTIAN FORECAST...
BROAD...COLD...AND UNSTABLE NORTHWEST FLOW WILL CONTINUE OVER THE
BERING AND ALEUTIANS FOR THE NEXT FEW DAYS. NUMEROUS SNOW SHOWERS
WILL PERSIST. LOW PRESSURES EMBEDDED IN THE NORTHWEST FLOW WILL
CONTINUE TO BE POORLY HANDLED BY THE MODELS AND WILL CONTINUE TO
BRING BRIEFLY HEAVY SNOWFALL.

.AER/ALU...WATCH/WARNING SUMMARY
PUBLIC...NONE.
MARINE...STORM WARNING 350.
         GALE WARNINGS 120 130 185.
         HEAVY FREEZING SPRAY WARNINGS 160 180 185.

FOISY DEC 06