Small Craft Advisory 78, NWS Anchorage, AK

AREA FORECAST DISCUSSION
SOUTHCENTRAL AND SOUTHWEST ALASKA
500 PM AKST TUE JAN 20 2009

.MODEL DISCUSSION...
THE MODELS ARE IN GOOD AGREEMENT THROUGH WEDNESDAY NIGHT. PROBLEMS
BEGIN ON THURSDAY AS THE NEXT STORM SYSTEM MOVES TOWARD THE ALASKA
PENINSULA. MOST MODELS WANT TO MOVE THE LOW TOWARD THE GULF WHILE THE
ECMWF AND THE GFS ENSEMBLE MEAN MOVES IT INTO THE SOUTHEAST BERING BY
FRIDAY NIGHT. CURRENT HPC MID RANGE GUIDANCE IS SIMILAR TO THE ECMWF
SOLUTION. SO WE ARE STRONGLY LEANING TOWARD THE ECMWF SOLUTION.

.ANALYSIS AND UPPER LEVELS...
THE UPPER TROUGH OVER THE COPPER RIVER BASIN AND THE GULF OF ALASKA
CONTINUES TO DRIFT EAST. AREAS OF SNOW ASSOCIATED WITH THE TROUGH
FELL ACROSS THE COPPER RIVER BASIN. AN UPPER RIDGE OVER SOUTHWEST
INTERIOR, SEWARD PENINSULA AND CHUKCHI SEA IS ALSO DRIFTING EAST.

AT THE SURFACE...HIGH PRESSURE CENTERED NEAR BARROW COVERS MOST OF
MAINLAND ALASKA. SKIES HAVE BEEN CLEARING FROM THE WEST THROUGH
MONDAY NIGHT AND TUESDAY MORNING WITH AREAS OF MORNING FOG
DEVELOPING. A COMPLEX LOW PRESSURE SYSTEM REMAINS OVER THE CENTRAL
ALEUTIANS WITH A WEATHER FRONT ACROSS THE NORTHERN AND EASTERN BERING
SEA.

.SHORT TERM FORECAST...
THE UPPER TROUGH OVER EASTERN ALASKA WILL MOVE INTO THE YUKON
TERRITORY WEDNESDAY. THE UPPER RIDGE OVER WESTERN ALASKA WILL BECOME
NEARLY STATIONARY OVER EASTERN MAINLAND THURSDAY.

AT THE SURFACE...HIGH PRESSURE CENTER ALONG THE NORTH SLOPE WILL MOVE
INTO NORTHWEST CANADA THURSDAY. AN AREA OF LOW PRESSURE REMAINS OVER
THE ALEUTIANS AND BERING SEA THROUGH THURSDAY. THE WEATHER FRONT OVER
THE EASTERN BERING WILL MOVE INTO BRISTOL BAY AND THE KUSKOKWIM DELTA
WEDNESDAY MORNING THEN MOVE INTO THE SOUTHWEST INTERIOR AND THURSDAY.
A LOW DEVELOPING SOUTH OF THE CENTRAL ALEUTIANS WEDNESDAY WILL DEEPEN
TO 980 MB AND MOVE TO ABOUT 250 MILES SOUTH OF COLD BAY THURSDAY.

SOUTHCENTRAL AK AND THE GULF...SNOW OVER THE COPPER RIVER BASIN WILL
DIMINISH FROM THE WEST THIS EVENING. SKIES WILL CONTINUE TO CLEAR
FROM THE WEST THROUGH TONIGHT. LOCAL GUSTY NORTH WINDS WILL DEVELOP
ALONG THE CENTRAL GULF COAST AND THE ALASKA RANGE TONIGHT AND
WEDNESDAY.  RAIN WILL MOVE INTO KODIAK ISLAND WEDNESDAY NIGHT AND
INTO THE SOUTHERN KENAI PENINSULA THURSDAY.

SOUTHWEST ALASKA...RAIN OVER THE ALASKA PENINSULA WILL BECOME RAIN
SHOWERS THURSDAY. SNOW WILL MOVE INTO THE KUSKOKWIM DELTA WEDNESDAY
AND WILL SPREAD INTO THE SOUTHWEST INTERIOR THURSDAY. STRONG
SOUTHEAST WINDS DEVELOPING ALONG THE KUSKOKWIM DELTA COAST WILL
CREATE AREAS OF BLOWING SNOW WEDNESDAY AND WEDNESDAY NIGHT.

BERING SEA AND ALEUTIANS...THE WEATHER FRONT OVER THE CENTRAL BERING
AND EASTERN ALEUTIANS WILL MOVE NORTHEAST AND MOVE ONSHORE OVER
SOUTHWEST ALASKA WEDNESDAY. AREA OF GUSTY SOUTHEAST WINDS TO THE EAST
OF THE FRONT WILL MOVE THROUGH THE EASTERN BERING TONIGHT AND
WEDNESDAY.

.LONG TERM FORECAST...
THE UPPER HIGH OVER THE EASTERN MAINLAND AND YUKON TERRITORY WILL
MOVE INTO NORTHWEST CANADA SATURDAY. A SWALLOW UPPER RIDGE WILL
REMAIN OVER THE GULF THROUGH SATURDAY. THE AREA OF LOW PRESSURE OVER
THE CENTRAL BERING WILL MOVE INTO WESTERN ALASKA BY SATURDAY. CLOUDS
AND PRECIPITATION OVER WESTERN ALASKA AND THE GULF WILL SPREAD TO THE
REST OF SOUTHCENTRAL ALASKA BY SATURDAY.

.AER/ALU...WATCH/WARNING SUMMARY
PUBLIC...NONE.
MARINE...GALE 150, 155, 160, 165, 170, 179, 180
FIRE WEATHER...NONE.

NM JAN 09