Small Craft Advisory 830, NWS Anchorage, AK

SOUTHCENTRAL AND SOUTHWEST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE ANCHORAGE AK
500 AM AKDT SAT OCT 2 2010

.ANALYSIS AND UPPER LEVELS...

UPPER LEVEL LOW OVER BRISTOL BAY THIS MORNING WITH A LOBE EXTENDING
ACROSS KODIAK AND ANOTHER LOBE ACROSS THE WESTERN ALEUTIANS. A
BLOCKING RIDGE EXTENDS FROM THE NORTHERN ROCKIES TO WEST OF
BARROW...WITH A WEAKER RIDGE OVER KAMCHATKA AND EASTERN RUSSIA. AT
THE SURFACE...AN ELONGATED DOUBLE LOW IS APPROACHING THE KENAI
PENINSULA EAST OF HOMER WHERE IT WILL RAPIDLY RECONSOLIDATE UPON
LANDFALL...WHILE A SECOND LOW IS OVER THE EASTERN BERING. A THIRD
MUCH MORE AMORPHOUS LOW IS SOUTH OF ATTU...BUT WILL BECOME A MAJOR
PLAYER IN THE GULF EARLY IN THE WEEK.

.MODEL DISCUSSION...

MODELS ARE IN BROAD AGREEMENT FOR THE NEXT SEVERAL DAYS...BUT THE NAM
SEEMS TO HAVE A BETTER HANDLE ON A FEW CRITICAL DETAILS...SO THE
FIRST THREE DAYS OF THE FORECAST RESEMBLE THE NAM SOLUTION. THE GULF
LOW...HAVING SPLIT INTO A DOUBLE LOW FEATURE...WILL MERGE AS IT MAKES
LANDFALL EAST OF HOMER THIS MORNING. THE LOW IS THEN RAPIDLY ABSORBED
INTO THE BROAD AREA OF LOW PRESSURE OVER WESTERN AK. SUN AFTERNOON A
SMALL LOW ROTATES INTO THE GULF AND MOVES INTO PRINCE WILLIAM SOUND
MON AFTERNOON BEFORE DISSIPATING. BY THIS TIME THE LOW OVER THE
EASTERN BERING MERGES WITH THE NEXT NORTH PACIFIC LOW WELL SOUTH OF
THE AKPEN. THIS THIRD PACIFIC LOW MOVES INTO THE GULF MON NIGHT INTO
TUE AND REACHES THE NORTH GULF COAST TUE NIGHT.

.SHORT TERM FORECAST...

IN THE WEST...WEAK TO SMALL CRAFT STRENGTH NORTHWEST FLOW WILL
CONTINUE THROUGH TUE WITH SHOWERS OVER THE ENTIRE BERING AND THE
ALEUTIANS.

FOR SOUTHWEST AK...SHOWERS WILL PERSIST UNTIL TUE AFTER THE EASTERN
BERING SEA LOW MOVES ACROSS THE AKPEN AND MERGES WITH THE THIRD
PACIFIC LOW.

SOUTH AND EAST OF THE AK RANGE...PERIODS OF RAIN AND STRONG CHANNELED
WIND WILL OCCUR WITH EACH LOW THAT MOVES INTO THE NORTHERN GULF. SOME
DRYING CAN FINALLY BE EXPECTED FROM THE WEST ON TUE AS THE THIRD LOW
MOVES TO THE NORTHEASTERN GULF COAST TO DECAY.

.LONG TERM FORECAST...

IN THE WEST WEAKENING NORTHWEST FLOW WILL DIMINISH SHOWERS UNTIL A
WEATHER FRONT ENTERS THE BERING FROM THE WEST NEXT WEEKEND. GENERALLY
DRY CONDITIONS WILL OCCUR OVER SOUTHWEST AK AS WEAK HIGH PRESSURE
BUILDS AND STORM SYSTEMS REMAIN TO THE SOUTH INTO NEXT WEEKEND. AFTER
THE LOW IN THE NORTHEASTERN GULF DECAYS WEDNESDAY...SOUTHEAST OF THE
AK RANGE WILL HAVE DRY CONDITIONS FOR THE REST OF THE WEEK.

.AER/ALU...WATCH/WARNING SUMMARY
PUBLIC...FLOOD WARNING 125
MARINE...STORM 120
         GALE 125 129 130 165 170 172 185
FIRE WEATHER...NONE

DS OCT 10