Heavy Snow in Alaska, January 22, 2005

SOUTHEAST ALASKA FORECAST DISCUSSION
1100 AM AST FRI JAN 21 2005

.SHORT RANGE...WEATHER FRONT ALREADY PUSHING THROUGH THE SOUTHERN
PART OF THE PANHANDLE WITH THE PRESSURE CHECK OF THE FRONT
THROUGH SOUTHERN CLARENCE STRAIT AND THEN NORTH TO AT LEAST
KLAWOCK.  EXPECT THE FRONT TO CONTINUE NORTH AND EAST THROUGH
TODAY IT SHOULD REACH THE CROSS SOUND-PETERSBURG LINE BY
00Z...AND THROUGH THE JUNEAU AREA BY 03Z (6 PM) AND YAKUTAT
SKAGWAY AREA BY 06Z.  THE BIG DIFFERENCE THAT EXPECT THE FRONT TO
GO THROUGH THE LYNN CANAL AREA ALOFT RIDING OVER THE TOP OF THE
COLD AIR FROM AROUND THE BERNERS BAY AREA AND NORTHWARD.

FRONT PULLING A COOLER OFF SHORE FLOW AHEAD OF THE FRONT EVIDENT
BY THE COOLING ALOFT ON THE SENSORS AROUND JUNEAU... THUS EXPECT
THE MIXED TERMINOLOGY OVER THE NORTH CENTRAL INNER CHANNELS TO
WORK OUT FAIRLY WELL.  SNOW OVER THE FAR NORTHERN LYNN CANAL
SHOULD PERSIST INTO SATURDAY BEFORE MIXING.

A PAIR OF SECONDARY TRAILING WAVES IN THE FLOW WILL MOVE NORTH
AND ACROSS THE PANHANDLE. THE FIRST IS SMALLER AND PUSHES ACROSS
THE CENTRAL PANHANDLE FRIDAY NIGHT... THE SECOND IS MORE
PRONOUNCED SURFACE WAVE THE ROLLS UP TO THE SOUTHERN PANHANDLE
SATURDAY AFTERNOON. WILL KEEP THE SNOW WARNINGS FOR THAT AREA.

HIGH WIND WARNING OVER THE SKAGWAY ZONE (018) REPORTING NEAR BUT
NOT QUITE WARNING LEVEL GUSTS. ALMOST PULLED IT TO A MAX WIND
ADVISORY (55 MPH) ... ALSO AS FORECAST GRADIENTS ARE TO DECREASE
OVER THE NEXT COUPLE OF HOURS...BUT WILL LEAVE IT UP FOR THE TIME
BEING.

.LONG RANGE...BY SUN MORNING THE SURFACE LOW IN THE GULF WILL
WEAKEN TO AROUND 985 MB AND BE NEAR PRINCE WILLIAM SOUND. A SMALL
SURFACE RIDGE OVER BRITISH COLUMBIA AND THE PANHANDLE WILL
GENERATE SOUTHERLY WINDS IN THE INNER CHANNELS SUNDAY. WINDS WILL
BECOME LIGHT OVER MOST OF THE PANHANDLE SUN EVENING AS THE LOW
DISSIPATES AND THE SURFACE RIDGE MOVES EAST. A WAVE DEVELOPING
WELL SOUTH ALONG THE FRONT AROUND 35N WILL MOVE NORTH INTO QUEEN
CHARLOTTE SOUND SUN NIGHT OR MON. AS THE LOW PASSES SOUTH OF THE
PANHANDLE IT WILL BRING NORTHERLY WINDS AND A CHANCE OF
PRECIPITATION TO THE SOUTHERN PANHANDLE. FOR THE REMAINDER OF THE
PANHANDLE THE APPROACH OF THE LOW WILL ACT TO END LINGERING
SHOWERS ON MON AND PERHAPS GENERATE SOME SUNBREAKS BY AFTERNOON.

THE EXTENDED MODELS ARE STILL OSCILLATING BETWEEN PERSISTENT
SOUTHWESTERLY FLOW ALOFT AND RETURNING THE THE AREA TO COLD
OFFSHORE FLOW BY REBUILDING THE ARCTIC SURFACE HIGH AND
SUPPORTING UPPER LEVEL CUT OFF LOW OVER NORTHWEST CANADA. TODAYS
00Z GFS APPEARS TO BE TRYING TO DO BOTH AT THE SAME TIME.
ALTHOUGH THIS WOULD MAKE A MOST EXCELLENT SNOW PATTERN FOR JUNEAU
IT SEEMS A RATHER UNLIKELY SOLUTION. THEREFORE I AM RATHER
SKEPTICAL ABOUT ANYTHING FROM WED ON.

.AJK...WATCHES/WARNINGS/ADVISORIES
PUBLIC......HIGH WIND WARNING AKZ018 ENDING BY/THIS AFTERNOON
         ...HEAVY SNOW/WINTER WEATHER WARNING AKZ018-019
            TONIGHT-SAT
         ...WIND ADVISORY AKZ017-022-023-027-28

MARINE...CURRENT GALES PKZ022-033>052
      ...CURRENT SMCR PKZ011>021-023>032

BMB - JER