Gale Warning 5, NWS Juneau, AK

SOUTHEAST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE JUNEAU AK
143 PM AKST THU JAN 7 2010

.SHORT TERM...THE LATEST SATELLITE IMAGERY SHOW A LOW PRESSURE
SYSTEM LIFTING OUT OF THE NORTH PACIFIC WITH AN ASSOCIATED
WEATHER FRONT OVER THE SOUTHERN AREAS AND MOVING NORTH. MOST
STATIONS ACROSS THE PANHANDLE ARE REPORTING RAIN WITH THE
EXCEPTION TO THE FAR NORTHERN AREAS AND OVER INTERIOR AREAS OF
MISTY FJORD. THE SNOW OVER THE NORTHERN AREAS IS MIXED WITH
FREEZING RAIN NEAR PAHN BUT ALL SNOW NEAR PAGY AS THERE IS VERY
WARM AIR ALOFT OVER THE COLD FREEZING TEMPS AT THE SURFACE. WIND
WISE THIS MORNING...THE STRONGEST WINDS ARE OVER THE GULF WITH
MAX SMALL CRAFT WINDS. OVER LAND THE SOUTHERN AREAS AND COASTAL
AREAS ARE CONTINUING TO SEE AN INCREASE IN THE WINDS AS THE LOW
AND WEATHER FRONT LIFTS NORTH WITH GUSTS TO 30 MPH. THE REST OF
THE AREA ARE SEEING RELATIVELY LIGHT WINDS.

 THE UPPER RIDGE OVER BC THIS AFTERNOON WILL CONTINUE TO GET
PUSHED TO THE EAST AS A STRONG UPPER LEVEL LOW/TROF LIFTS NW INTO
THE EASTERN GULF TONIGHT AND INTO THE NORTHERN GULF BY FRIDAY
AFTERNOON. THE ASSOCIATED SURFACE LOW WILL CONTINUE TO DEVELOP
THIS AFTERNOON AND BE AROUND 985MB BY THIS EVENING BEFORE IT
BEGINS TO FILL LATE TONIGHT INTO FRIDAY AS IT BECOMES VERTICALLY
STACKED AND THE UPPER LEVEL DYNAMICS WEAKENS. THE UPPER LEVEL
FLOW AND SOURCE REGION OF THIS WEATHER SYSTEM WILL CONTINUE THE
WAA OVER THE PANHANDLE. THIS WAA WILL TO KEEP ALL OF THE PRECIP
IN THE LIQUID FORM EXCEPT FOR THE FAR NORTHERN AREAS AS THEY WILL
CONTINUE TO KEEP THE COLD AIR AT THE SURFACE TO PRODUCE FREEZING
RAIN THROUGH TONIGHT. SO WITH THAT SAID THE WINTER WEATHER
WARNING WILL CONTINUE UNTIL 5AM FRIDAY MORNING. THERE WILL BE
SOME SNOW ACCUMULATIONS WITH AMOUNTS FROM 3 TO 6 INCHES BUT MOST
OF THAT WILL BE ALONG THE HIGHWAY AS IN TOWN ICE MAY ACCUMULATION
UP TO 1/2 INCH. THE THINKING RIGHT NOW IS THAT THE COLD AIR WILL
SLOWLY GET ERODED AWAY FROM THE HAINES AREA AND THE FREEZING RAIN
WILL BECOME A MIX OF RAIN AND SNOW THROUGH FRIDAY BUT
ACCUMULATIONS ALONG THE HIGHWAY. ALONG WITH THE RAIN ACROSS THE
PANHANDLE AND THE LACK OF WINDS OVER THE INNER CHANNELS THERE
WILL BE AREAS OF FOG THAT WILL LINGER THROUGH TONIGHT AND PERSIST
INTO FRIDAY MORNING. THE PRECIP WILL CONTINUE OVER THE AREA INTO
FRIDAY BUT THERE WILL BE SOME TAPERING OFF OF THE RAIN OVER THE
SOUTHERN AREAS BY FRIDAY AFTERNOON AS THE FRONT LIFTS NORTH AND A
WEAK UPPER RIDGE MOVES OVER THE AREA.

 THE WINDS ALONG THE COASTAL AREAS WILL CONTINUE TO INCREASE AS
THE LOW MOVES INTO THE EASTERN GULF THROUGH TODAY AND TONIGHT.
THERE IS A STRONG 70KT LLJ THAT WILL MOVE OVER THE SOUTHERN AREAS
AND COASTAL AREAS LATE THIS AFTERNOON INTO THE EARLY EVENING
HOURS. SO THE WINDS WILL CONTINUE TO INCREASE AND THERE WILL BE
AREAS OF GUSTS TO 45KT. THESE STRONG GUSTS WILL SLOWLY DIMINISH
LATE TONIGHT AS THE LOW DRIFTS NW AWAY FROM THE PANHANDLE AND THE
LLJ WILL WEAKEN. GALE FORCE WINDS WILL DEVELOP OVER THE EASTERN
GULF AS THE FRONT AND LOW LIFTS NORTH TONIGHT. THESE WINDS WILL
RELAX THROUGH FRIDAY BUT SE WINDS TO 25 KT WILL DOMINATE THE
EASTERN GULF WITH SEAS IN THE TEENS.

&&

.LONG TERM...STILL EXPECT STRONG UPPER RIDGE OVER WESTERN NOAM TO
SLOWLY MOVE EAST THROUGH THE WEEKEND AS UPPER TROUGH MOVES ACROSS
ARE. RIDGE REBUILDS EARLY NEXT WEEK AND THEN SLOWLY SLIDES EAST.
A SERIES OF MODERATE TO STRONG LOW PRESSURE SYSTEMS ORIGINATING IN
THE CENTRAL PACIFIC WILL RIDE NORTH ALONG WEST SIDE OF RIDGE AND
INTO THE EASTERN GULF AND THEN CURVE NW AND WE KEN OVER NORTHERN
GULF. THE ECMWF HAS CORRECTED ITSELF ON TODAYS RUN AND WAS
PREFERRED AS IT KEPT STRONGEST GRADIENTS AND COLDEST AIR NORTH OF
COAST MOUNTAINS. ALTHOUGH GFS IS SIMILAR AND CONSISTENT WITH
ITSELF IT STILL HAS STRONGER GRADIENTS AND COLDER AIR SPREAD
ACROSS FAR NORTHERN PANHANDLE. THE NAM HAS EXTREME NE GRADIENTS
ACROSS NORTHEAST GULF COAST AND VERY COLD AIR OVER FAR NORTH AND
WAS REJECTED FOR USE TODAY.

MOST OF SE ALASKA IS BETWEEN SYSTEMS FRIDAY NIGHT AND SATURDAY AND
WILL KEEP POPS IN CHANCE TO LIKELY CATEGORY. THIS IS SLOWER THAN
PREVIOUS RUNS.

BY SATURDAY NIGHT NEXT STRONG 950 MB COMPLEX LOW MOVES TO
SOUTHERN GULF WITH ASSOCIATED OCCLUSION WRAPPING NORTH INTO
SOUTHERN PANHANDLE BY LATE SATURDAY NORTH AND WEAKENING ACROSS
NORTHERN SUNDAY AFTERNOON. WILL SEE STRONG GALES TO POSSIBLE
STORMS IN SOUTHERN WATERS. WITH HIGH PERSISTING IN YUKON HAVE
STRONG NORTHERLY GRADIENTS ACROSS FAR NORTH WITH GAP WINDS
APPROACHING STORM FORCE. RAIN WILL BE AT LEAST MODERATE WITH THIS
SYSTEM AND SOUTHERN ZONES COULD SEE 3 INCHES TO THE 1 INCH FAR
NORTH. SOME COLD AIR STILL IN PLACE FOR HAINES WHICH COULD SEE
SIGNIFICANT SNOW. AS LOW PASSES JUST SW OF PAYA SUNDAY NIGHT INTO
MONDAY NE GRADIENTS BECOME VERY LARGE AND NOW CONSIDERING THE
POSSIBLE THAT PAYA WILL HAVE STRONG NE WINDS IN TON BY MONDAY
MORNING...ALTHOUGH THINK MODELS WILL STILL ADJUST IN UPCOMING
RUNS.

WITH THE RAINS AND HIGH FREEZING LEVELS SMALL STREAM AND URBAN
TYPE FLOODING IS BECOMING A CONCERN AND WILL DISCUSS WITH RFC
SINCE OCCURRING OVER WEEKEND.

MILD WET PATTER CONTINUES INTO NEXT WEEK WITH SEVERAL MORE SHORT
WAVES MOVING ACROSS THE AREA.

.AJK WATCHES/WARNINGS/ADVISORIES...
PUBLIC...WIND ADVISORY UNTIL 3 AM AKST FRIDAY FOR AKZ023-027-028.
         WINTER STORM WARNING UNTIL 5 AM AKST FRIDAY FOR AKZ019.
MARINE...GALE WARNING FOR PKZ022-036-041>043-051-052.
         SMALL CRAFT ADVISORY FOR PKZ021-033>035.

&&

ABJ/MM