Small Craft Advisory 47, NWS Anchorage, AK

AREA FORECAST DISCUSSION...CORRECTION
SOUTHCENTRAL AND SOUTHWEST ALASKA
400 PM AST WED JAN 16 2008

CORRECTED WATCH/WARNING SUMMARY

.MODEL DISCUSSION...NAM MODEL DID WELL YESTERDAY INTO THIS MORNING AS
IT WAS THE ONLY MODEL TO LOCK ONTO THE POLAR LOW THAT WAS SOUTH OF
DUTCH HARBOR YESTERDAY AND BRING IT TO PRINCE WILLIAM SOUND EARLY
TODAY. THIS MAY BE IMPORTANT TO KEEP IN MIND AS THE GFS AND NAM
DIFFER ON THE STRENGTH AND MOVEMENT OF ANOTHER LOW THAT IS DEVELOPING
SOUTH OF THE ALASKA PENINSULA TODAY AND WILL MOVE TO THE NORTH GULF
COAST THURSDAY NIGHT. THE NAM KEEP THE LOW CLOSER TO THE COAST AND
STRONGER THAN THE GFS WHICH IS A BIT WEAKER AND MOVES THE LOW NEAR
MIDDLETON ISLAND. THE LOW IS CURRENTLY IN A DATA VOID AREA OF THE
NORTH PACIFIC SO IT IS HARD TO SEE HOW THE MODELS ARE CURRENTLY
HANDLING IT. IT MOST LIKELY WILL HAVE A STRENGTH SOMEWHERE IN BETWEEN
THESE TWO SOLUTIONS. IN THE BERING SEA THE GFS AND ECMWF ARE QUITE
SIMILAR WITHOUT ANY SIGNIFICANT DIFFERENCES UNTIL AROUND 72 HOURS. AT
THIS POINT THE MODELS ARE HAVING DIFFICULTY RESOLVING THIS COMPLEX
LOW AND WHICH LOW CENTER WILL BE THE MAIN CENTER AND WHICH ONES WILL
BE WEAKER.

.ANALYSIS AND UPPER LEVELS...JET STREAM IS MOVING SOUTHWEST TO
NORTHEAST THROUGH THE GULF AS IT RIDES OVER A LARGE RIDGE OVER THE
WEST COAST OF NORTH AMERICA. A DEVELOPING LOW NEAR 50N 160W CAN BE
SEEN ON SATELLITE AND WILL MOVE INTO THE NORTHERN GULF THURSDAY
NIGHT. WEST OF THIS SYSTEM THERE IS A LOW SPINNING AROUND NORTH OF
AMCHITKA THAT IS BRINGING SNOW SHOWERS BUT DOES NOT HAVE UPPER LEVEL
SUPPORT AND WILL SLOWLY WEAKEN AS IT DRIFTS NORTHWARD.

.SHORT TERM FORECAST...SNOW WILL END THIS EVENING FOR THE COPPER
RIVER BASIN. FOG AND OR STRATUS HAS A GOOD CHANCE OF DEVELOPING FROM
BRISTOL BAY ALL THE WAY TO THE CANADIAN BORDER WITH FRESH SNOWFALL
AND CLEARING SKIES. SNOW SHOWERS WILL ALSO PERSIST THROUGH THE
ALEUTIAN ISLANDS AND PRIBILOFS.

.LONG TERM FORECAST...LARGE PUSH OF WARM AIR WILL BE MOVING INTO THE
STATE THIS WEEKEND. A HIGH AMPLITUDE WARM RIDGE WILL BEGIN TO BUILD
INTO THE AREA FRIDAY AND A JET STREAK WILL RUN SOUTH TO NORTH ALONG
160W FROM 40N INTO NORTHERN ALASKA BY SATURDAY. AT THIS TIME A STRONG
LOW WILL MOVE THROUGH THE BERING SEA AND GREATLY TIGHTEN THE PRESSURE
GRADIENT AS 850 MB TEMPERATURES IN THE GULF OF ALASKA REGION TO 2 TO
4 DEGREES C ABOVE. THE RESULT WILL PROBABLY BE RAIN IN BRISTOL BAY
AND A CHINOOK EVENT SATURDAY FOR SOUTH CENTRAL ALASKA...INCLUDING
ANCHORAGE. BRISTOL BAY ANS SOUTHWEST ALASKA WILL LIKELY SEE RAIN AS
THIS WARM WET SYSTEM MOVES THROUGH SATURDAY.

.AER/ALU...WATCH/WARNING SUMMARY
PUBLIC...NONE.
MARINE...GALE 172 352.
         HEAVY FREEZING SPRAY 185 411 412.
FIRE WEATHER...NONE.

JAN 08