Small Craft Advisory 258, NWS Anchorage, AK

AREA FORECAST DISCUSSION
SOUTHCENTRAL AND SOUTHWEST ALASKA
500 AM AST SUN MAR 19 2006

.DISCUSSION...

UPPER LEVEL LOWS OVER EASTERN RUSSIA AND THE NORTHERN BERING THIS
MORNING...WITH A TROUGH EXTENDING FROM THESE LOWS ACROSS WESTERN
ALASKA AND KODIAK...AND INTO THE GULF OF ALASKA SOUTH TO 40 N. THESE
FEATURES ARE SURROUNDED BY HIGH PRESSURE RIDGES OVER THE SOUTHEAST
AND NEAR THE KAMCHATKA PENINSULA. AT THE SURFACE...THE DOMINANT
PLAYERS ARE A PAIR OF LOWS WHICH VIRTUALLY COVER THE BERING AND
NORTHERN GULF...WITH A WEAKER LOW JUST SOUTH OF THE WESTERN
ALEUTIANS.

MODELS ARE IN GOOD AGREEMENT IN MERGING THE ALEUTIAN LOW WITH THE
BERING LOW...AND THEN BRINGING THE BERING LOW INTO WESTERN ALASKA
TODAY. THE GULF LOW MOVES INTO THE GENERAL AREA OF WESTERN PRINCE
WILLIAM SOUND LATER THIS MORNING WHERE IT PERSISTS THROUGH THE
AFTERNOON. BY TONIGHT BOTH LOWS MERGE OVER THE AKPEN BEFORE MOVING
BACK INTO THE GULF MON. THE LOW THEN MOVES SLOWLY SOUTH INTO THE
NORTH PACIFIC ON WED. WHILE ALL THIS IS HAPPENING...A RIDGE OF HIGH
PRESSURE MOVES ACROSS THE BERING BY WED.

IN THE EAST...STRONG WINDS ASSOCIATED WITH THE GULF LOW MOVE INTO
THE NORTH GULF COAST TODAY. WIND ACROSS THE CHUGACH IS EXPECTED TO
WEAKEN THIS MORNING AND ALLOW FOR SNOWFALL FOR THE ANCHORAGE ZONE.
THIS WILL DIMINISH TONIGHT AS THE LOWS MIGRATE INLAND AND MERGE.
LIGHT SNOW SHOULD FALL OVER MOST OF THE EASTERN DOMAIN AND PERSIST
UNTIL THE LOWS MIGRATE BACK INTO THE GULF ON MON. LINGERING SNOW
SHOWERS SHOULD END BY WED.

IN THE WEST...AREAS OF FOG THIS MORNING FOLLOWED BY SNOW AS THE LOW
MOVES ONSHORE TODAY. VERTICALLY STACKED LOW PRESSURE MOVING ACROSS
THE MOUNTAINS WILL KEEP SNOW FALLING OVER SOUTHWEST ALASKA THROUGH
MONDAY. NORTHWEST FLOW AS THE LOW MOVES INTO THE GULF WILL KEEP
SHOWERS ON UPWIND SIDES OF MOUNTAINS UNTIL LATE MON WHEN MOISTURE IS
FINALLY EXHAUSTED. THE BERING SEA RIDGE FINALLY CUTS OFF ANY
LINGERING PRECIPITATION WHEN IT MOVES INLAND TUE.

OVER THE ALEUTIANS...STRONG WEST WIND AND SHOWERS SHOULD PERSIST OVER
THE CHAIN TODAY. AS THE RIDGE BUILDS IN FROM THE WEST...NORTHWEST
FLOW WILL CONTINUE TO BRING SHOWERS TO THE EASTERN ISLANDS OVERNIGHT
BEFORE BECOMING ISOLATED. THE NEXT WEATHER FRONT...FROM A KAMCHATKA
PENINSULA LOW...WILL BEGIN TO BRING GALES TO WESTERN PORTIONS OF THE
ISLANDS MON AFTERNOON INTO WED.

IN THE EXTENDED...SEVERAL FRONTS FROM THE KAMCHATKA LOW...WITH GALES
AND PRECIPITATION...WILL MOVE ACROSS THE WESTERN BERING TOWARD THE
WEEKEND. THE BERING SEA RIDGE WILL MOVE ACROSS THE SOUTHERN PART OF
THE STATE INTO THE WEEKEND WITH INCREASINGLY DRY CONDITIONS EAST OF
THE ALEUTIAN AND ALASKA RANGES.

.AER/ALU...WATCH/WARNING SUMMARY
PUBLIC...NONE
MARINE...HEAVY FREEZING SPRAY 160 185
         STORMS 120
         GALES 150 155 160 165 170 171 172 176 179
FIRE WEATHER...NONE

DS MAR 06