Small Craft Advisory 447, NWS Anchorage, AK

AREA FORECAST DISCUSSION
SOUTHCENTRAL AND SOUTHWEST ALASKA
500 AM AKDT MON JUN 01 2009

.ANALYSIS AND UPPER LEVELS...
IN THE UPPER LEVELS...RIDGING CONTINUES TO BUILD OVER THE EASTERN
GULF OF ALASKA...WITH A HIGH AMPLITUDE TROUGH STRETCHING FROM THE
BERING SEA DOWN INTO THE NORTH PACIFIC. BETWEEN THESE FEATURES...A
SOUTHERLY JET IS STREAMING COOL AND MOIST AIR OVER SOUTHWESTERN
ALASKA.

AT THE SURFACE...HIGH PRESSURE IS BUILDING OVER THE CENTRAL GULF AND
SOUTHCENTRAL. A LARGE LOW COMPLEX EVIDENT ON SATELLITE IMAGERY IS
CENTERED SOUTH OF THE CENTRAL ALEUTIANS. MOIST SOUTHERLY FLOW IS
LEADING TO WIDESPREAD RAIN ACROSS THE AKPEN...BRISTOL BAY...AND THE
KUSKOKWIM.

.MODEL DISCUSSION...
MODELS ARE IN SATISFACTORY AGREEMENT THROUGH MIDWEEK. AS HAS BEEN
TYPICAL THE PAST COUPLE OF DAYS...UNCERTAINTY EXISTS CONCERNING THE
EVOLUTION OF INDIVIDUAL LOW CENTERS OVER THE ALEUTIANS AND BERING
SEA. DISAGREEMENTS ALSO CONTINUE AS TO HOW FAR WEST THE RIDGE OVER
THE GULF OF ALASKA MAY MANAGE TO BUILD. ALL SOLUTIONS DO AGREE ON
KEEPING THE OMEGA BLOCK IN PLACE THROUGH AT LEAST MID WEEK. THE GFS
WAS USED TO CONSTRUCT THE MORNING PACKAGE DUE TO CONTINUED
CONSISTENCY IN THE SHORT TERM.

.SHORT TERM FORECAST...
.SOUTHCENTRAL...
GENERALLY FAIR SKIES AND MODERATING TEMPERATURES WILL BE THE RULE
ACROSS SOUTHCENTRAL THROUGH THE MIDDLE OF THE WEEK...AS HIGH PRESSURE
REMAINS IN CONTROL OVER THE AREA. WARM AIR ASSOCIATED WITH THE RIDGE
WILL LEAD TO TEMPERATURES APPROACHING OR EXCEEDING THE MIDDLE
SEVENTIES FOR AREAS LIKE THE MATSU VALLEY AND COPPER RIVER BASIN.
MOIST SOUTHERLY FLOW AFFECTING KODIAK ISLAND WILL RESULT IN A
CONTINUED CHANCE OF RAIN...WITH SOME MOISTURE TRIGGERING SHOWERS OVER
THE ALASKA RANGE. ANOTHER CONCERN THAT WILL HAVE TO BE MONITORED IS
HOW FAR INLAND THE MARINE LAYER WILL PENETRATE UNDERNEATH HIGH
PRESSURE...WITH LOW STRATUS BEING THE MAIN CONCERN FOR COASTAL
LOCATIONS.

.SOUTHWEST...
MOIST SOUTHERLY FLOW WILL KEEP WIDESPREAD RAIN AND GUSTY SOUTHEAST
WINDS OVER THE AREA THROUGH AT LEAST MID WEEK. HIGHEST PRECIP AMOUNTS
AND WINDS WILL OCCUR ALONG COASTAL PORTIONS OF THE KUSKOKWIM
DELTA...BRISTOL BAY...AND AKPEN.

.BERING SEA AND ALEUTIANS...
CLOUDY AND RAINY CONDITIONS WILL PERSIST OVER THE AREA THROUGH MID
WEEK AS THE LOW COMPLEX CONTINUES TO AFFECT THE AREA. THE WESTERN
ALEUTIANS SHOULD REMAIN MAINLY DRY AS THE BULK OF THE MOISTURE
REMAINS OVER THE CENTRAL AND EASTERN ISLANDS.

.LONG TERM FORECAST...
THE STABLE PATTERN IS EXPECTED TO CONTINUE THROUGH THE
WEEK...ALTHOUGH DETAILS OF THE RIDGE'S INFLUENCE CONTINUE TO BE
CLOUDY. GENERALLY EXPECT UNSETTLED WEATHER TO REMAIN THE STORY OVER
SOUTHWEST AK AND THE BERING SEA/ALEUTIANS. THE FARTHER WEST THE RIDGE
MANAGES TO BUILD...THE WARMER AND DRIER IT WILL BE ACROSS
SOUTHCENTRAL.

.AER/ALU...WATCH/WARNING SUMMARY
PUBLIC...NONE
MARINE...GALE 150 160
FIRE WEATHER...NONE

NRH MAY 09