Gale Warning 8, NWS Juneau, AK

SOUTHEAST ALASKA FORECAST DISCUSSION
1200 PM AST FRI JAN 25 2008

.SYNOPSIS...
.SHORT RANGE...THE SURFACE LOW OVER THE NORTH CENTRAL GULF WILL
CONTINUE TO DRIFT ESE AND MOVE ONSHORE JUST NORTH OF PASI AND
THEN SLIDE SE OVER THE SOUTHERN HALF OF SE AK. THIS LOW IS
PRODUCING HEAVY SNOW ACROSS MUCH OF THE PANHANDLE EXCEPT FOR THE
SOUTHERN THIRD. ATTM IT LOOKS LIKE THERE IS TOO MUCH WARM AIR FOR
THE SOUTHERN AREAS AND COASTAL AREAS TO STAY ALL SNOW THEY WILL
BEGIN TO MIX WITH RAIN THROUGH THE AFTERNOON BUT WITH CAA BEHIND
THE LOW THEY WILL CHANGE BACK TO SNOW LATE TONIGHT. THERE WILL BE
SOME GUSTY WINDS DEVELOPING THIS AFTERNOON AS THE LOW MOVES OVER
THE AREA SO THERE IS WIND ADVY FOR ZONES 23...28...29 THROUGH
TONIGHT.

THE SNOW WILL CONTINUE TO PILE UP THROUGH THE AFTERNOON AND INTO
TONIGHT FOR MOST OF THE INNER CHANNELS. AS THE LOW DRIFTS SE
THROUGH THE SOUTHERN PANHANDLE THE ASSOCIATED UPPER TROF WILL
MOVE OVER THE AREA THIS WILL ENHANCE THE SNOW FALL RATES OVER THE
INNER CHANNELS THROUGH PAWG. SNOW AMOUNTS WILL RANGE FROM 8 TO 14
INCHES WITH LOCALLY HIGHER AMOUNTS. THE SNOW WILL TAPPER OFF FROM
NORTH TO SOUTH AS THE LOW PULLS AWAY AND THE NORTHERLY WINDS
INCREASE.

AS THE MAIN UPPER LOW MOVES THROUGH THE AREA A VERY COLD SHORT
WAVE EMBEDDED IN THE LOW WAVE TROF WILL SLIDE SOUTH THROUGH
TONIGHT AND BE OVER THE NORTHERN PANHANDLE BY SAT AFTERNOON. THIS
WILL USHER IN VERY COLD TEMPS ALONG WITH VERY WINDY CONDITIONS.
WILL KEEP THE BLOWING SNOW ADVY FOR THE FAR NORTHERN INNER
CHANNELS AND WILL ADD WIND ADVY FOR MOST OF THE FORECAST AREA BY
SAT AFTERNOON. WITH THE VERY COLD TEMPS AND STRONG WINDS IT WILL
FEEL LIKE 20 BELOW WITH THE WIND CHILL AND THERE WILL BE AREAS OF
BLOWING SNOW AS THE SNOW FALLING ATTM IS VERY LIGHT AND WILL GET
BLOWN ALL OVER THE PLACE.

FOR THE MARINES...VERY STRONG NORTHERLY WINDS WILL DEVELOP
THROUGH LATE TONIGHT INTO SAT AS THE HIGH IN THE YUKON
STRENGTHENS. MAX GALES WILL DEVELOP OVER NORTH/SOUTH CHANNELS
WITH GUSTS TO 60 KT FROM INTERIOR GAPS. AREAS ALONG THE NORTHERN
GULF WILL SEE OUTFLOW WINDS TO 70 KT BY SAT AFTERNOON.

.LONG RANGE...
DANGEROUSLY COLD AND WINDY. THAT IS THE SCREAMING MESSAGE FOR THE
EXTENDED RANGE SAT NIGHT THROUGH MON. THE WEATHER GRADUALLY
MODIFIES AFTER TUE. LITTLE OR NO CHANGE TO CURRENT FCSTS.

SECOND SHORT WAVE AROUND UPR LOW SWINGS OUT OF INTERIOR AK AND
INTO NRN PANHANDLE SAT EVENING AND PUSHES SOUTH THROUGH SUN. THIS
WAVE HAS VERY COLD AIR BEHIND IT. FIRST EFFECT WILL BE POTENTIAL
FOR MOUNTAIN WAVE WIND STORM /IE TAKU/ SAT NIGHT. AS COLD AIR AND
HIGH PRESSURE BUILD INLAND ON SUN-MON...STRONGEST WINDS WILL BE
MORE GAP FLOW TYPE OUT OF PASSES AND BAYS. HIGH END WIND
ADVISORIES VERY PROBABLE SAT NIGHT INTO SUN OR EARLY MON BUT WILL
HOLD OFF HEADLINING THIS IN FORECASTS UNTIL SNOW EVENT ENDS.
CONDITIONS ALONG HIGHWAYS OUT OF HAINES AND SKAGWAY WILL BE
TREACHEROUS THIS WEEKEND DUE TO BITTER COLD... HIGH WINDS...
BLOWING SNOW AND DANGEROUS WIND CHILL. SIMILARLY HAZARDOUS IN ALL
MARINE ZONES LATER THIS WEEKEND WITH HEAVY FREEZING SPRAY. PEOPLE
NEEDING TO BE OUTSIDE LATE SAT TO EARLY MON IN SE AK...
PARTICULARLY NORTHERN INNER CHANNELS...SHOULD PREPARE THEMSELVES
FOR DANGEROUS COMBINATION OF COLD AND WIND. AND WITH ALL THE NEW
SNOW WE SHOULD EXPECT AREAS OF NEAR ZERO VISIBILITY IN BLOWING
SNOW.

UPR RIDGE OVER AK MAINTAINS ITS POSITION TUE BUT A WEATHER SYSTEM
WILL BE UNDER CUTTING RIDGE. OPERATIONAL GFS TAKES THIS SYSTEM
FAR SOUTH OF AREA BUT SEVERAL OF THE ENSEMBLE SOLUTIONS INDICATE
IT MAY BRUSH BY THE SOUTHERN PANHANDLE ZONES EARLY TUE WITH LIGHT
SNOW. AFTER MID WEEK THE UPPER RIDGE BREAKS DOWN A BIT TO A
FLATTER WLY FLOW. THIS SHOULD ALLOW FOR GRADUAL WARMING AND MOIST
ONSHORE FLOW ACROSS THE FORECAST AREA. THIS PATTERN OFTEN LEADS
TO SNOW AND IS ALREADY MENTIONED IN FCST.  TA

.AJK...WATCHES/WARNINGS/ADVISORIES
PUBLIC...HEAVY SNOW WARN...AKZ17 THRU 4PM...AKZ18-19 THRU
      9PM...AKZ20>22/25>26 29 THRU 11PM
      BLSN ADVY...AKZ18 19 9PM-6AM
      WIND ADVY...AKZ23 27 28
MARINE...GALES ENTIRE COASTAL WATERS...PKZ11 12 36
      SCA...PKZ13 21 22 31>35