Small Craft Advisory 604, NWS Anchorage, AK

AREA FORECAST DISCUSSION
SOUTHCENTRAL AND SOUTHWEST ALASKA
500 PM AKDT SAT AUG 1 2009

.ANALYSIS AND UPPER LEVELS...
UPPER AIR...AN UPPER LOW OVER THE CENTRAL ALEUTIANS EXTENDS A TROUGH
NORTHWARD ACROSS THE EASTERN BERING SEA AND CHUKCHI SEA. A RIDGE OF
HIGH PRESSURE REMAINS OVER BRITISH COLUMBIA AND THE YUKON TERRITORY.
AT THE SURFACE...A HIGH LIES JUST SOUTH OF THE GULF OF ALASKA WITH A
RIDGE INTO CENTRAL ALASKA. A COMPLEX LOW LIES SOUTH OF THE ALEUTIANS.

.MODEL DISCUSSION...
MODELS ARE IN GOOD AGREEMENT OVER THE SOUTHERN MAINLAND THROUGH
MONDAY. MODELS CONTINUE TO TROUBLE HANDLING THE LOW SOUTH OF THE
ALEUTIANS THOUGH GFS APPEARS TO HAVE THE MOST CONSISTENT SOLUTION.

.SHORT TERM FORECAST...
UPPER LEVELS...A RIDGE WILL DEVELOP OVER THE GULF OF ALASKA TONIGHT
AND WILL BUILD INTO SOUTHCENTRAL ALASKA BY MONDAY THEN MOVE TOWARD
THE ALCAN BORDER TUESDAY. THE UPPER LOW OVER THE CENTRAL ALEUTIANS
WILL DRIFT INTO THE EASTERN ALEUTIANS TUESDAY.

SOUTHCENTRAL ALASKA AND THE GULF...THE SURFACE RIDGE OVER THE GULF
AND SOUTHCENTRAL REGION WILL REMAIN OVER THE AREA BUT GRADUALLY
WEAKEN AND DRIFT EAST THROUGH TUESDAY. SKIES WILL REMAIN PARTLY
CLOUDY WITH ISOLATED SHOWERS OVER THE INTERIOR SECTIONS THROUGH
MONDAY. A WEAK SHORT WAVE TROUGH WILL MOVE THROUGH WESTERN GULF AND
THE SOUTHERN COOK INLET TONIGHT AND WILL BRING A LIGHT RAIN TO KODIAK
ISLAND AND POSSIBLY THE SOUTHERN KENAI PENINSULA. A WEATHER FRONT IS
EXPECTED TO MOVE INTO THE WESTERN GULF TUESDAY. MORE CLOUDS AND RAIN
WILL MOVE INTO KODIAK ISLAND MONDAY NIGHT AND INTO THE KENAI
PENINSULA AND SOUTHERN SUSITNA VALLEY TUESDAY.

SOUTHWEST MAINLAND...THE GENERAL SOUTHERLY FLOW ACROSS THE REGION
WILL KEEP IT MOSTLY CLOUDY WITH SCATTERED SHOWERS THROUGH MONDAY
NIGHT. AN UPPER SHORT WAVE OVER BRISTOL BAY WILL SWING NORTH AND
BRING LIGHT RAIN TONIGHT AND SUNDAY MORNING. A WEATHER FRONT IS
EXPECTED TO BRING ANOTHER SHOT OF RAIN TO THE AREA MONDAY NIGHT AND
TUESDAY.

BERING SEA AND ALEUTIANS...THE LOW SOUTH OF THE CENTRAL ALEUTIANS
WILL MOVE INTO THE EASTERN ALEUTIANS MONDAY AND INTO THE SOUTHEAST
BERING TUESDAY. ANOTHER LOW PRESSURE SYSTEM OVER EASTERN SIBERIA WILL
MOVE SOUTH INTO THE WESTERN ALEUTIANS MONDAY. MOST OF THE RAIN
ASSOCIATED WITH THE ALEUTIAN SYSTEM WILL REMAIN OVER THE EASTERN
ALEUTIANS AND SOUTHEASTERN BERING THROUGH TUESDAY. AN AREA OF RAIN
WILL MOVE THROUGH THE WESTERN BERING WITH THE SIBERIAN SYSTEM SUNDAY
NIGHT AND MONDAY.

.LONG TERM FORECAST...
THE UPPER RIDGE OVER THE EASTERN GULF AND THE ALCAN BORDER WILL MOVE
OVER SOUTHEAST ALASKA AND THE YUKON TERRITORY THURSDAY. THE UPPER LOW
WILL REMAIN OVER THE SOUTHEAST BERING THROUGH THURSDAY. THIS WILL
ALLOW MORE CLOUDS AND RAIN TO MOVE BACK INTO SOUTHCENTRAL ALASKA
DURING THE LATTER HALF OF NEXT WEEK. CLOUDS AND OCCASIONAL RAIN WILL
PERSIST OVER SOUTHWEST ALASKA AND THE EASTERN BERING THROUGH
THURSDAY.

.AER/ALU...WATCH/WARNING SUMMARY
PUBLIC...NONE.
MARINE...GALE 155.
FIRE WEATHER...NONE.

NM AUG 09