Small Craft Advisory 883, NWS Juneau, AK

SOUTHEAST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE JUNEAU AK
545 AM AKST TUE DEC 27 2011

.SHORT TERM...A STRONG LOW HAS MOVED ONSHORE NEAR ICY BAY AND IS
QUICKLY FILLING AND REDEVELOPING INLAND. WHAT IS LEFT OF THE
SECOND WRAP HAS MOVED THROUGH PAYA AND IS PULLING BACK TO THE NW.
A FLAT RIDGE IS BUILDING ACROSS THE EASTERN GULF THAT WILL MOVE
OVER SOUTHEAST ALASKA BY THIS AFTERNOON AND INTO CANADA TONIGHT. A
DEVELOPING 965 MB GALE FORCE LOW ORGANIZING IN THE NORTH PACIFIC
NEAR 50/150 IS FORECAST TO MOVE INTO THE SOUTHEAST GULF TONIGHT
AND BE NEAR SITKA BY WEDNESDAY AFTERNOON.

WESTERLY GALES CONTINUE ACROSS THE GULF THAT IS FORECAST TO
DIMINISH AND BECOME SE BY THIS AFTERNOON. SEAS PEAKED AT AROUND 30
FEET LAST NIGHT AND SINCE HAVE FALLEN TO AROUND 20 FEET. WILL
CONTINUE TO SEE DOWNWARD TREND IN SEAS BUT PROBABLY AT A SLOWER
PACE THIS AFTERNOON. E WINDS PICK UP TO GALE EASTERLIES OVERNIGHT
AHEAD OF LOW. STILL HAVE A SLY GALE THROUGH LYNN CANAL WITH LOW NOW
IN YUKON. AS IT MOVES AWAY AND NEXT TROUGH APPROACHES TO SOUTH
WILL SEE GRADIENT FLIP TO THE NORTH AND INCREASE TO SMCR
OVERNIGHT.

RADAR AND SATELLITE SHOW PLENTY OF SHOWERS MOVING ONSHORE
SOUTHEAST ALASKA IN WSW FLOW WITH CAA. ALL AREAS NOW COLD ENOUGH
FOR SNOW WITH ONLY SOUTHERN COAST MIXING WITH RAIN SHOWERS THIS
AFTERNOON. SHOWERS APPEAR TO BE MOVING QUICKLY AND ONLY PRODUCING
SMALL ACCUMULATIONS. MAIN EXCEPTION IS IN FAR NORTH WHERE MORE
PERSISTENT SNOW HAS ADDED UP TO 1-2 FEET NEAR HAINES AND STILL
HAVE POSSIBILITY OF A FEW QUICK INCHES IN PAYA. SHOWERS EXPECTED TO
DECREASE LATER THIS AFTERNOON WITH ONLY A CHANCE OF SHOWERS
THROUGH THE EVENING.

NEXT SYSTEM APPROACHING PANHANDLE TONIGHT. SUBSIDENCE AHEAD OF
FRONT SHOULD CAP SHOWERS THIS EVENING WITH STEADY RAIN AND SNOW
SPREADING TO SOUTHERN AND COASTAL AREA BY MORNING. SNOWFALL
AMOUNTS EXPECTED TO BE IN 1-2 INCH RANGE FOR THE LATE PART OF TONIGHT.

NO MAJOR MODEL DISCREPANCIES THROUGH THE SHORT TERM WITH EXITING
OR APPROACHING SYSTEM. A NAM AND GFS BLEND SEEMED TO WORK WELL PRES
AND WINDS.

&&

.LONG TERM...NEXT LOW MOVING ACROSS THE NORTH PACIFIC AND
SOUTHERN GULF TURNS NORTHWARD TO MOVE ONSHORE SOUTHEAST ALASKA
AROUND THE SITKA REGION OF THE COAST. THE LOW IS WEAKENING AS IT
MOVE INLAND. GENERAL LOW PRESSURE CONTINUES OVER THE NORTHERN
GULF. WED NIGHT TO THURSDAY THERE IS ANOTHER SYSTEM MOVING AND AT
THE TIME BEING THIS ONE IS EXPECTED TO MOVE ON SHORE THE BRITISH
COLUMBIA COAST SOUTH OF HAIDA GWAII THURSDAY EVENING.

THE TEMPERATURES OVER THE PANHANDLE LOOK TO REMAIN GENERALLY COOL
ENOUGH FOR PRECIPITATION TO BE SNOW... OR A MIX MOST LOCATIONS.
HOWEVER MOST AREAS ARE NOT SEEING A VERY COLD AIR MASS SO A LOT OF
THE SNOW FALLING IS THE AREA AROUND FREEZING FOR THE HIGHS AND
LOWS THROUGH MID WEEK. THIS HAS THE POTENTIAL TO LIMIT THE
ACCUMULATIONS AMOUNT AS THE WETTER SNOW RATIOS THAT ARE RESULTING
DEPTHS COMPACTING BETTER.

MODEL CONSISTENCY IS NOT GREAT FROM THE WEEKEND ONWARD AND AS A
RESULT WILL CONTINUE TO GUIDANCE FROM HPC FOR THE EXTENDED TIME
FRAME. OVERALL THE IDEA IS LOW PRESSURE WILL CONTINUE TO MOVE INTO
THE GULF WITH OUT A PATTERN SHIFT INTO THE DAYS THAT START THE NEW
YEAR.

.AJK WATCHES/WARNINGS/ADVISORIES...
PUBLIC...WINTER STORM WARNING UNTIL 9 AM AKST THIS MORNING FOR AKZ019.
         STRONG WIND UNTIL 6 AM AKST EARLY THIS MORNING FOR AKZ018.
         WINTER WEATHER ADVISORY UNTIL 9 AM AKST THIS MORNING FOR AKZ017.
MARINE...GALE WARNING FOR PKZ012-013-033-035-036-041>043-051-052.
         SMALL CRAFT ADVISORY FOR PKZ011-021-022-031-032-034-053.

&&

MM/BEZENEK