Small Craft Advisory 659, NWS Anchorage, AK

AREA FORECAST DISCUSSION
SOUTHCENTRAL AND SOUTHWEST ALASKA
500 PM AKDT MON SEP 1 2008

.MODEL DISCUSSION...
THE GFS AND ECMWF CONTINUE TO BE IN GOOD AGREEMENT THROUGH THURSDAY
AFTERNOON THEN BEGIN TO DIVERGE TOWARD THE END OF THE WEEK.

.ANALYSIS AND UPPER LEVELS...
THE MAIN UPPER LOW OVER KODIAK ISLAND REMAIN VERTICALLY STACK ABOVE
THE SURFACE AND BOTH ARE WEAKENING. AN UPPER RIDGE PERSISTS OVER
WESTERN CANADA AND THE NORTHERN MAINLAND.

.SHORT TERM FORECAST...
UPPER AIR...
THE UPPER LOW OVER KODIAK ISLAND WILL MOVE INTO BRISTOL BAY TONIGHT
AND TUESDAY THEN WILL DRIFT INTO THE WESTERN INTERIOR WEDNESDAY AND
THURSDAY. A TROUGH EXTENDING EAST OF THE LOW OVER THE GULF OF ALASKA
WILL SWING NORTH AND WEAKEN ALONG THE CENTRAL GULF COAST AND KENAI
PENINSULA TONIGHT AND WILL PROBABLY DISSIPATE OVER THE SOUTHCENTRAL
INTERIOR TUESDAY. ANOTHER SHORT WAVE TROUGH EXTENDING SOUTH OF THE LOW
WILL ROTATE INTO THE WESTERN GULF TUESDAY NIGHT AND PASS THROUGH
SOUTHCENTRAL ALASKA WEDNESDAY. AREAS OF SHOWERS ASSOCIATED WITH EACH
UPPER WILL MOVE THROUGH SOUTHCENTRAL ALASKA OVER THE NEXT FEW DAYS.
SCATTERED SHOWERS OVER BRISTOL BAY WILL SPREAD NORTH WITH THE UPPER
LOW INTO THE SOUTHWEST INTERIOR THROUGH THURSDAY.

AT THE SURFACE...
THE SURFACE LOW OVER KODIAK ISLAND WILL DISSIPATE NEAR KING SALMON
TONIGHT. ANOTHER LOW ABOUT 400 MILES SOUTH OF THE EASTERN ALEUTIANS
WILL MOVE TO NEAR KODIAK ISLAND TUESDAY NIGHT THEN WEAKEN AS IT MOVES
INTO THE NORTHERN GULF WEDNESDAY AND THURSDAY. MORE RAIN IS EXPECTED
TO MOVE INTO KODIAK ISLAND AND THE WESTERN GULF TUESDAY AND WILL MOVE
INTO THE KENAI PENINSULA AND PRINCE WILLIAM SOUND TUESDAY NIGHT AND
WEDNESDAY. THE RAIN WILL BECOME SHOWERS ON THURSDAY.

.LONG TERM FORECAST...
TOWARD THE END OF THE WEEK, AN UPPER RIDGE WILL INTO THE GULF OF
ALASKA WITH A STRONG UPPER LOW COMING OUT OF THE NORTH PACIFIC INTO
BRISTOL BAY BY SATURDAY. A STRONG SOUTHERLY JET CAUGHT BETWEEN THESE
TWO SYSTEMS WILL MOVE INTO KODIAK ISLAND AND THE WESTERN GULF SATURDAY
AND BRING MORE RAIN TO SOUTHERN ALASKA OVER THE WEEKEND.

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

*** SEP 08