Small Craft Advisory 255, NWS Anchorage, AK

SOUTHCENTRAL AND SOUTHWEST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE ANCHORAGE AK
157 PM AKDT WED MAR 26 2014

ANALYSIS AND UPPER LEVELS...
THE QUIET PATTERN OVER THE MAINLAND IS PERSISTING UNDER THE
UPPER LEVEL BLOCKING RIDGE THAT EXTENDS FROM THE HIGH CENTERED
OVER THE ARCTIC COAST TO THE GULF OF ALASKA. LOW PRESSURE ALOFT
AND DOWN TO THE SURFACE IS WELL SOUTH OF THE MAINLAND AND WE
EXPEXT THIS SYSTEM TO MOVE EAST TOWARD QUEEN CHARLOTTE ISLAND OVER
THE NEXT COUPLE OF DAYS. THE UPPER LOW CENTERED OVER THE ASIAN
MAINLAND WITH A TROUGH AND ANOTHER UPPER LOW IN THE WESTERN BERING
SEA IS SUPPORTING THE WEAK LOW MOW JUST WEST OF SHEMYA. A WEAK
TROUGH EXTENDS FROM THE NORTHWEST BERING SEA TO THE PRIBILOF
ISLANDS. SATELLITE IMAGERY SHOWS THIS FEATURE AND THE MODELS HAVE
CAPTURED IT WELL. IT IS EXPECTED TO DISSIPATE AS IT MOVES EAST
TOWARD THE BERING SEA COAST OVERNIGHT TONIGHT.

MODEL DISCUSSION...
THE MODELS CONTINUE TO BE IN EXCELLENT AGREEMENT INTO EARLY NEXT
WEEK. THE LOW AND FRONT MOVING INTO THE WESTERN BERING SEA TONIGHT
THROUGH FRIDAY IS THE PRIMARY CONCERN. THE MODELS HAVE A GOOD
HANDLE ON THIS SYSTEM AS WELL AS THE TROUGH THAT IS CURRENTLY IN
THE VICINITY OF THE PRIBILOF ISLANDS. EXPECT MOISTURE TO STREAM
OVER THE RIDGE IN ADVANCE OF THE INCOMING FRONT ASSOCIATED WITH
THIS LOW OVER THE NEXT FEW DAYS AND THIS IS WELL DEPICTED BY THE
MODELS. THE MODELS ARE SHOOWING THE WARM FRONT TRAVERSING ACROSS
THE BERING SEA JUST NORTH OF THE CHAIN WITH OUR EXPECTATION OF
SNOW DEVELOPING OVER THE PRIBILOF ISLANDS TOINGHT. THE COLD FRONT
WILL MOVE ACROSS THE CENTRAL ALEUTIANS AS IT OCCLUDES BY THU
AFTERNOOON. THIS FRONT EVENTUALLY MOVES TO THE WESTERN ALASKA
PENINSULA BY FRI AFTERNOON TO FRI NIGHT. OVERALL THE MODELS ARE
HANDLING THIS WELL AND THE EXPECTED WIND FIELD SHOULD REMAIN FOR
THE MOST PART AT MINIMAL GALE FORCE AND PREDOMINANTLY IN THE 25 TO
30 KT RANGE.

SHORT TERM FORECAST...

SOUTHCENTRAL ALASKA...
THE SOUTH CENTRAL REGION WILL REMAIN UNDER THE DRY CONDITIONS AT
LEAST THROUGH THIS WEEKEND. SOME PATCHY FOG IS POSSIBLE MAINLY IN
LOW LYING AREAS WHERE THE INVERSION WILL SET UP IN THE OVERNIGHT
HOURS. THE GAP WIND CONCERNS ARE DIMINISHING AS THE GRADIENTS HAVE
RELAXED ACROSS THE REGION. EXPECT THE LARGE DIURNAL TERMPERATURE
RANGES TO PERSIST FOR THE NEXT SEVERAL DAYS.

SOUTHWEST ALASKA...
THE WEAK ONSHORE PUSH FROM THE RIDGE OVER THE EASTERN BERING SEA
IS RESULTING IN LOWER CLOUDS AND VISIBILITIES THAT ARE MAINLY AN
AVIATION CONCERN. THE REMNANTS OF THE TROUGH THAT PASSED THROUGH
THE PRIBILOF ISLANDS TODAY IS PUSHING TOWARD THE KUSKOKWIM DELTA
COAST AS IT DISSIPATES. THE HIGHER CLOUD SHIELD SHOULD HELP TO
RETARD THE DEVELOPMENT OF THE INVERSION OVERNIGHT TONIGHT AND THUS
WE DO NOT EXPECT THE CLOUDS AND VISIBILITIES TO BE AS LOW TONIGHT
AND THU MORNING.

BERING SEA/ALEUTIANS...
THE LOW WEST OF SHEMYA IS MOVEING NORTH WITH THE ASSOCIATED FRONT
EXPECTED TO MOVE ACROSS THE ALEUTIANS THOUGH THU EVENING. AS
PREVIOUSLY DISCUSSED THE WIND IS EXPECTED TO REMAIN AT THE MINIMAL
GALE FORCE LEVEL AND BELOW AND THE MAIN IMPACT WILL BE THE RAIN
AND SNOW WITH THIS FRONT THOUGH WE DO NOT EXPECT ANY ACCUMULATIONS
OF SNOWFALL.

LONG TERM FORECAST...
TTHE RIDGE OVER THE MAINLAND WILL CONTINUE TO BLOCK THE EASTWARD
PROGESSION OF THE BERING SEA LOWS THROUGH THE WEEKEND. HOWEVER THE
RIDGE IS SLIDING TO THE EAST AND THE UPPER LEVEL TROUGH WILL SLIDE
OVER THE TOP OF THE RIDGE SAT AND SUN BRINGING SOME CLOUDS AND AN
INCREASED THREAT FOR PRECIPITATION TO THE BRISTOL BAY AND
KUSKOKWIM DELTA REGIONS.

&&

WATCHES/WARNINGS/ADVISORIES...
PUBLIC...NONE.
MARINE...GALES 175 176 177 178 411 413
FIRE WEATHER...NONE.

&&

SAM MAR 14