Winter Storm Watch 9, NWS Juneau, AK

SOUTHEAST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE JUNEAU AK
330 PM AKST FRI NOV 30 2012

.SHORT TERM...OVERALL THE PATTERN HAS NOT ALTER SIGNIFICANTLY.
SAME VERTICALLY STACKED LOW WITH HIGH PRESSURE OVER NORTHWEST
CANADA. ORIGINALLY THOUGHT TONIGHT FORECAST  ISSUE WAS GOING TO
BE THE WINDS ACROSS THE NORTHERN INNER CHANNELS. STORM FORCE
SUSTAINED OVER MARINE WATERS IN THE PANHANDLE...AND STRONGER
GUSTS AS WELL. REISSUED THE WARNING FOR TAKU WINDS IN THE JUNEAU
AREA THROUGH THE AFTERNOON AND EVENING. INITIAL THINKING IS THAT
IT SHOULD TAPER OFF THROUGH THE EARLY EVENING.

 FOR SATURDAY THE ISSUE WAS TO BE WINDS IN THE NORTH WITH SNOW
SPREADING INTO THE SOUTH CENTRAL PANHANDLE. SNOW AMOUNTS WAS TO
BE THE CONCERN BUT THOUGHT TO REMAIN BELOW ADVISORY BUT WITH
FURTHER REVIEW WAS COLDER AIR BEING PULLED SOUTH UNDER THE
SOUTHERLY AIR ALOFT. WILL BE GOING WITH SLIGHT CHANCE OF SOME
FREEZING RAIN LATE.

 ADDITIONAL MARINE PRODUCT ISSUE IS THE FREEZING SPRAY AND HEAVY
FREEZING SPRAY AFFECTING NORTHERN INNER CHANNEL AREAS SOME OUTER
WATERS NEAR YAKUTAT WITH THE STRONGER OUTFLOW LOCATIONS.

&&

 .LONG TERM...INTERESTING FORECAST UPCOMING FOR THE WEEKEND AS WE
HAVE A SHORT WAVE RIDING UP THE OUTER COAST SAT NIGHT WITH
CONTINUED OUTFLOW WINDS. AREAS ALONG THE PANHANDLE FROM SUMNER
STRAIT NORTHWARD WILL BE UNDER THE GUN FOR SNOW SAT NIGHT INTO
SUNDAY WITH THE SUBSTANTIAL COLD AIR STILL IN PLACE IN THE INNER
CHANNELS. THERE IS NOT A VERY STRONG MOISTURE PLUME ASSOCIATED
WITH THE SHORT WAVE SO MOST OF THE PRECIP WILL BE COMING FROM THE
OVERRUNNING OF THE WARMER AIR OVER THE COLD ARCTIC AIR. THE MAIN
BAND OF ISENTROPIC LIFT LOOKS LIKE IT WILL BE JUST SOUTH OF
JUNEAU EARLY SAT EVENING AND WILL SLOWLY SPREAD OVER ANGOON,
JUNEAU AND HOONAH BY LATE SAT EVENING. HIGHER RESOLUTION MODELS
SEEM TO BE IN DECENT AGREEMENT ON THIS BUT THE BAND LOOKS TO BE
RATHER NARROW SO SNOW AMOUNTS MAY TURN OUT TO BE LOWER IN SOME
AREAS DEPENDING ON WHERE THE BAND GOES. SNOW ACCUMULATIONS EXPECTED
TO BE IN EXCESS OF 4 TO 9 INCHES BY MIDDAY SUNDAY AS THE MAIN
BAND SLOWLY MOVES THROUGH THE AREA. AREAS FARTHER WEST AND NORTH
MAY SEE SNOW OUT OF THIS A LITTLE LATER INTO THE DAY ON SUN BUT
DUE TO THE CONTINUED OUTFLOW THE BAND WILL BE WEAKENING ON SUNDAY.

 OUTFLOW WINDS CONTINUE THROUGH THE LONG TERM PERIOD AS THE HIGH
IN THE YUKON REMAINS BUT IN A WEAKER STATE THAN IT HAS BEEN.
LACKING THE REINFORCING SHOTS OF COLD AIR THE ONLY THING
SUSTAINING IT IS THE LINGERING COLD AIR THAT IS TRAPPED ON THE
CANADIAN SIDE OF THE MOUNTAINS. AS A RESULT THE OUTFLOW WIND WILL
NOT BE A STRONG AS THEY HAVE BEEN. LYNN CANAL SHOULD STILL HAVE
ENOUGH PRESSURE GRADIENT AND SOME COLD AIR FLOWING OVER THE
PASSES TO HAVE MIN GALE FORCE WINDS CONTINUING INTO NEXT WEEK WITH
FREEZING SPRAY. OTHER OUTFLOW AREAS WILL ALSO CONTINUE TO BLOW
BUT AT LOWER MAGNITUDES THAN WHAT HAS BEEN OBSERVED THIS WEEK.

 LOOKING FARTHER OUT MODELS ARE STILL IN FLUX FOR HOW THEY ARE
HANDLING THE VARIOUS SHORTWAVES THAT ARE COMING INTO THE
PANHANDLE FROM THE SOUTH. THE STRONGER WAVE THAT WAS FORECAST FOR
TUES HAS NOW BEEN ABANDON BY MOST OF THE LONG RANGE MODELS. IN
ITS PLACE IS A BROAD WEAKER TROUGH THAT WILL LIFT NORTH OVER THE
PANHANDLE ON TUES INSTEAD. OVERALL GUIDANCE WENT TOWARD THE EC
AND NAM IN THE MID RANGE AND EC/HPC IN THE EXTENDED PERIODS.
FORECAST CONFIDENCE IS ABOUT AVERAGE.

.AJK WATCHES/WARNINGS/ADVISORIES...
PUBLIC...HIGH WIND WARNING UNTIL 6 PM AKST THIS EVENING FOR AKZ025.
         STRONG WIND THROUGH SATURDAY AFTERNOON FOR AKZ025.
         STRONG WIND UNTIL 6 PM AKST THIS EVENING FOR AKZ022.
         STRONG WIND THROUGH SATURDAY AFTERNOON FOR AKZ017>019-029.
MARINE...HEAVY FREEZING SPRAY WARNING FOR PKZ013.
         HEAVY FREEZING SPRAY WARNING FOR PKZ012.
         STORM WARNING FOR PKZ012-022.
         GALE WARNING FOR PKZ011-013-021-031-032-035-043-051.
         SMALL CRAFT ADVISORY FOR PKZ033-034-036-041-042-053.
         SMALL CRAFT ADVISORY DUE TO SEAS FOR PKZ052.

&&

BEZENEK/EAL