Small Craft Advisory 136, NWS Anchorage, AK

SOUTHCENTRAL AND SOUTHWEST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE ANCHORAGE AK
200 PM AKST SAT FEB 18 2012

.MODEL DISCUSSION...THOUGH THE ECMWF HANDLES THE LOW COMPLEX
CURRENTLY IN THE BERING SEA AND WESTERN ALEUTIANS THE BEST...IT IS
OVERALL THE OUTLIER IN MODEL SOLUTIONS. THE GFS SEEMS TO BE THE BEST
OVERALL COMPROMISE IN SOLUTIONS THROUGH THE SHORT TERM.

.UPPER LEVELS...
THE PROGRESSIVE PATTERN CONTINUES ACROSS MUCH OF THE NORTH PACIFIC.
THE BROAD LOW COMPLEX OVER THE BERING SEA ACTS AS THE FULCRUM FOR
SHORT WAVES MOVING ACROSS THE MAINLAND AND NORTH PACIFIC. THE SHORT
WAVE EXTENDING ACROSS THE BERING SEA TO OVER THE NE PACIFIC MOVES
OVER THE MAINLAND AND SE ALASKA SUN NIGHT AND WEAKENS. WAVES EMBEDDED
IN THE STRONG WESTERLY FLOW ACROSS THE NORTH PACIFIC DEVELOP AS THEY
TRACK EAST. ONE SUCH WAVE BECOMES  A CLOSED CENTER JUST SOUTH OF THE
AK PEN SUN NIGHT WHICH THEN MOVES TO THE NORTHERN GULF MON AFTERNOON.
A SECONDARY CENTER...THOUGH WEAKER...IS NOT FAR BEHIND.

.SHORT TERM FORECAST...
.SOUTHCENTRAL ALASKA...
A WEATHER FRONT EXTENDING ACROSS THE GULF OF ALASKA ALONG WITH A LOW
PRESSURE CENTER MOVING EAST OF KODIAK ISLAND TONIGHT WILL CONTINUE
SNOW OR MIX OVER COASTAL LOCATIONS THROUGH TONIGHT. WINDY CONDITIONS
ACROSS THE GULF AND SOUTHCENTRAL WILL DIMINISH OVERNIGHT AS THE LOW
CENTER WEAKENS. PRECIPITATION WILL BECOME MORE SHOWERY AND DIMINISH
AS WELL OVERNIGHT AS THE FRONTAL SYSTEM WEAKENS ALONG THE GULF COAST.
A DEVELOPING SYSTEM OVER THE NORTH PACIFIC MOVES TO NEAR KODIAK
ISLAND MON. THIS SYSTEM WILL BERING SIGNIFICANTLY STRONGER WINDS TO
THE GULF AND SOUTHCENTRAL. THE AIR WILL LIKELY BE WARMER WITH THIS
ONE...SO THERE WILL BE GREATER CHANCES OF RAIN ALONG THE COASTS.

.SOUTHWEST ALASKA...A FRONTAL BOUNDARY AND TRIPLE POINT LOW STRETCHES
ACROSS MUCH OF THE BERING SEA AND BRISTOL BAY. THIS SYSTEM WILL LIFT
NORTH TONIGHT AND SPREAD SNOW INTO THE INTERIOR AND BRING DRYING TO
THE COASTS. A WEAK FRONTAL WAVE WILL BRING INCREASING CHANCES OF SNOW
THE SW ALASKA AGAIN LATE SUN AFTERNOON/EVENING. THE NEXT WEATHER
PRODUCER AFTER THIS WILL BE THE STRONG LOW WHICH MOVES SOUTH OF THE
AK PEN MON MORNING AND TO KODIAK ON MON AFTERNOON. THIS SYSTEM WILL
BRING STRONG WINDS TO THE AK PEN AND BRISTOL BAY. PRECIPITATION ALONG
THE AK PEN WILL BE MIXED. SNOW OVER BRISTOL BAY MON WILL BECOME MIXED
IN THE AFTERNOON OVER THE SOUTHERN AND EASTERN END OF THE ZONE.

.BERING SEA AND ALEUTIANS...A LOW CENTERED OVER THE WESTERN ALEUTIANS
ENCOMPASSES THE BERING SEA. THIS WEAKENING LOW WILL BRING THE CHANCE
FOR SCATTERED SHOWERS ACROSS THE REGION AS IT SLOWLY MEANDERS TOWARDS
THE CENTRAL BERING BY SUNDAY.

.LONG TERM FORECAST...AN ACTIVE PATTERN WILL CONTINUE TO IMPACT THE
FORECAST REGION. UPPER LEVEL TROUGHING WILL DOMINATE MUCH OF THE
BERING AND GULF OF ALASKA THROUGH NEXT WEEK. HOWEVER...WITH THE JET
STREAM WELL TO THE SOUTH...NO STRONG LOW PRESSURE SYSTEMS ARE
EXPECTED TO FORM ACROSS THE REGION FOR THE NEXT WEEK.

.AER/ALU...WATCH/WARNING SUMMARY
PUBLIC...NONE
MARINE...GALE...120 132 150 155 170 185 352 411.
FIRE WEATHER...NONE

RMC FEB 12