Small Craft Advisory 251, NWS Anchorage, AK

SOUTHCENTRAL AND SOUTHWEST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE ANCHORAGE AK
134 PM AKDT SUN MAR 23 2014

.ANALYSIS AND UPPER LEVELS...AN UPPER LEVEL RIDGE CENTERED OVER
NORTHERN ALASKA CONTINUES TO BLOCK STORM SYSTEMS FROM THE
MAINLAND PART OF THE STATE TODAY. A VERTICALLY STACKED LOW OVER
THE KAMCHATKA PENINSULA IS SENDING A FRONT INTO THE CENTRAL BERING
SEA. THIS FRONT WILL CONTINUE TO WEAKEN AND IT PUSHES INTO THE
RIDGE OVER MAINLAND ALASKA. ANOTHER LOW WELL SOUTH OF THE GULF OF
ALASKA IS ALSO PUSHING A FRONT TOWARD THE STATE. THIS FRONT IS
ALSO NOT MAKING MUCH HEADWAY AGAINST THE RIDGE BUT IS TIGHTENING
THE PRESSURE GRADIENT OVER THE GULF.
THE GENERAL UPPER LEVEL PATTERN WILL PERSIST OVER THE STATE FOR
THE NEXT COUPLE OF DAYS.
&&

.MODEL DISCUSSION...THE COMPUTER MODELS CONTINUE TO BE IN GOOD
OVERALL AGREEMENT THROUGH THE MIDDLE OF THE WEEK. ON CAVEAT THAT
IS CHANGING SOME IS THAT THE ECMWF MODELS IS MORE AGGRESSIVE THAN
THE NAM OR GFS IN BRINGING A SHORT LIVED PUSH OF CLOUDS INTO SOUTH
CENTRAL ALASKA IN THE MIDDLE OF THE WEEK. OTHER THAN THAT THERE IS
LITTLE ELSE TO COMPARE AND CONTRAST ON THE MODELS TODAY.
&&

.SHORT TERM FORECAST...
SOUTHCENTRAL ALASKA...THE WEATHER PATTERN WILL CONTINUE TO KEEP
CLEAR SKIES OVER MOST OF THE AREAS THROUGH THE FIRST PART OF THE
WEEK. THERE WILL STILL BE SOME GUSTY NORTH TO NORTHEAST WINDS
THROUGH CHANNELED TERRAIN.

SOUTHWEST ALASKA...THERE ARE SOME CLOUDS IN SOUTHWEST ALASKA
AHEAD F THE WEAKENING WEATHER FRONT IN THE BERING SEA. THESE
CLOUDS WILL RETREAT WESTWARD OVERNIGHT BRINGING MOSTLY CLEAR
SKIES BACK TO THE AREA. THE GUSTY NORTHEAST WINDS ACROSS THE
REGION WILL ALSO SUBSIDE OVERNIGHT OR EARLY MONDAY AS THE
PRESSURE GRADIENT WEAKENS OVER THE AREA.

BERING SEA/ALEUTIANS...A WEATHER FRONT IS OVER THE CENTRAL BERING
SEA AND EASTERN ALEUTIANS TODAY THIS FRONT WILL ELONGATE AND WEAKEN
AS IT MOVES TO THE NORTHEAST IN THE BERING SEA AND EASTWARD OVER
THE ALASKA PENINSULA TONIGHT. MOST OF THE PRECIPITATION WITH THE
FRONT IS RAIN WHICH IS OVER THE EASTERN ALEUTIANS AND ALASKA
PENINSULA.
THERE ARE SOME SNOW SHOWERS MOVING INTO THE WESTERN ALEUTIANS
NEAR SHEMYA AND ATTU. THESE SNOW SHOWERS WILL CONTINUE TO MOVE
EASTWARD OVERNIGHT BUT WILL NOT BE VERY WIDESPREAD OR PRODUCE ANY
SIGNIFICANT SNOWFALL ACCUMULATIONS. &&

.LONG TERM FORECAST...THE PERSISTENT PATTERN LOOKS TO CONTINUE THROUGH NEXT
WEEK...ALTHOUGH MODELS ARE BEGINNING TO SHOW SIGNS OF THE RIDGE OVER
THE MAINLAND BREAKING DOWN BY NEXT WEEKEND. SINCE MODELS TEND TO TRY
TO BREAK DOWN BLOCKING PATTERNS TOO QUICKLY...IT WOULD SEEM PRUDENT
TO CONTINUE WITH PERSISTENCE UNTIL A PATTERN CHANGE BECOMES CLEAR.
THEREFORE...THE MAIN ACTIVE WEATHER WILL REMAIN OVER THE WESTERN
BERING...ALONG AND SOUTH OF THE ALEUTIAN CHAIN...AND ALONG OR SOUTH
OF THE SOUTHERN MAINLAND COAST THROUGH THE END OF NEXT WEEK.
&&

.AFC WATCHES/WARNINGS/ADVISORIES...
PUBLIC...NONE.
MARINE...GALE 127 128 132 150 155.
FIRE WEATHER...NONE.
&&

MAR 14