FXAK67 PAJK 292229
AFDAJK

SOUTHEAST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE JUNEAU AK
129 PM AKST SUN NOV 29 2009

.SHORT TERM...STRONG LOW JUST E PACV WILL CONTINUE NWD BUT WEAKEN
RAPIDLY THRU TONIGHT...WITH A NEW LOW FORMING OVER THE SW YUKON
THIS AFTERNOON AND HEADING NE AWAY FROM THE AREA TONIGHT. UPPER TROF
WILL MOVE E ACROSS THE AREA TONIGHT. DEEP LAYER RIDGE WILL BUILD
IN OVER THE ERN GULF AND SE AK MON. A COMPLEX FRONTAL SYSTEM WILL
MOVE INTO THE WRN GULF MON.

MAIN FORECAST CONCERN WILL BE HOW QUICKLY WINDS DROP OFF TONIGHT.
WITH BOTH THE PARENT LOW RAPIDLY WEAKENING AND THE SECONDARY LOW
MOVING AWAY FROM THE AREA...WINDS SHOULD DROP OFF FAIRLY RAPIDLY
THIS EVENING...ALTHOUGH IT WILL TAKE THE LONGEST TO DROP OFF
AROUND PAGY. WILL KEEP THE WIND ADVYS GOING FOR PAHN/PAGY THRU 06Z
TONIGHT. PAGY MAY NEED TO BE EXTENDED A BIT BEYOND THAT
HOWEVER...BUT NOT LIKELY BEYOND 09Z. THE CURRENT WIND GRIDS LOOKED
REALLY GOOD HANDLING THIS SO SAW NO REASON TO CHANGE ANY WIND
SPEEDS ALTHOUGH DID TWEAK SOME WIND DIRECTIONS A BIT. BY LATE
TONIGHT...WINDS ACROSS THE AREA SHOULD GENERALLY BE 15 KT OR
LESS...WITH NRN LYNN CANAL DROPPING TO THAT LEVEL MON MORNING.

OTHERWISE...COLD ADVECTION WILL CONTINUE THRU TONIGHT AND PRECIP
WILL BE SHOWERY. LOOKS LIKE IT WILL BE COLD ENOUGH FOR RAIN
SHOWERS TO CHANGE TO SNOW SHOWERS OVER THE NRN AND CENTRAL AREAS
LATE THIS EVENING. THE TROF MOVING THRU WILL LIKELY MEAN A MORE
ORGANIZED BAND OF SHOWERS WILL MOVE IN LATER THIS EVENING AND
OVERNIGHT...BUT NOT EXPECTING ANY LARGE SNOW ACCUMS. MAYBE AN INCH
OR TWO NEAR SEA LEVEL WHERE THE MOST SHOWERS OCCUR...WITH A FEW
INCHES AT UPPER ELEVATIONS ESPECIALLY OVER THE CENTRAL AREA. THE
SHOWERS SHOULD DIMINISH MON AS RIDGING BUILDS IN.

NEXT FRONT WILL BRING MORE PRECIP TO THE CENTRAL GULF AND MAY
ACTUALLY ENHANCE THE SHOWERS AGAIN AROUND PAYA MON. WILL KEEP
HIGHER POPS GOING THERE...WHILE THE REMAINDER OF THE PANHANDLE HAS
POPS DROP OFF SOMEWHAT THRU THE DAY.

&&

.LONG TERM...FAIRLY GOOD AGREEMENT THROUGH ABOUT WEDNESDAY THEN
SOME DIFFERENCES...MAINLY WITH STRENGTH AND POSITION OF A WAVE
MOVING NORTH ALONG THE FRONT OVER THE GULF ON TUESDAY. GUSTY WINDS
AHEAD OF THIS FRONT WILL LIKELY RESULT IN A POTENTIAL ADVISORY FOR
AKZ017 LATE MONDAY NIGHT AND EARLY TUESDAY BUT WILL JUST HEADLINE
WINDY AT THE MOMENT. THE LOW RESPONSIBLE WILL STAY EITHER IN
BRISTOL BAY OR THE SOUTHWEST ALASKA COAST. FROM WEDNESDAY THROUGH
THURSDAY SOUTHWEST FLOW ALOFT AND TROUGH WILL MOVE THROUGH
SOUTHEAST AS THE RIDGE ALOFT IS BUILT UP BY THE DEEP LOW
DEVELOPMENT SOUTH OF THE ALEUTIANS BY END OF WEEK.

THE END OF THE WEEK FORECAST HAS A LITTLE BIT OF DIFFERENCE BUILT
INTO IT AS A LOW MENTION BELOW DEVELOPS SOUTH OF THE EASTERN
ALEUTIANS BUT THERE IS SECOND LOW DEVELOPING SOUTH OF THERE...WITH
THE POTENTIAL ASSISTANCE OF FORMER TYPHOON NIDA. BOTH THE GFS AND
ECMWF ARE SHOWING AN IMPRESSIVE LOW 'BOMBING' FRIDAY NIGHT... DOWN
TO A 935 ON THE 12Z GFS TO A 926 MB ON THE ECMWF. THE GFS HAS THIS
LOW GOING FURTHER NORTH THAN THE GFS THROUGH SUNDAY. MEANWHILE
OVER NORTHWEST CANADA BOTH MODELS BUILDING 1050-ISH HIGH WITH THE
RIDGE INFLUENCE OUT INTO THE EASTERN GULF AN MODERATE TO WEAK
OUTFLOW GRADIENT DEPENDING ON MODEL SOLUTION. EITHER WAY LOOKS
LIKE NEXT WEEKEND WILL BE DRY. 

DID NOT REALLY ADJUST THE EXTENDED GRIDS...THERE IS SOME LARGER
DIFFERENCES ON THE POSITIONS OF THE RIDGE AND STRENGTH AND
ADJUSTMENTS WOULD HAVE MINOR AT THAT TIME. THROUGH THE FIRST PART
OF THE WEEK... USED A NAM SOLUTION...WITH SOME GFS INFLUENCE IN
IT. CONFIDENCE IS A LITTLE BETTER THAN AVERAGE FOR  THE FORECAST
PACKAGE.

.AJK WATCHES/WARNINGS/ADVISORIES...
PUBLIC...WIND ADVISORY UNTIL 4 PM AKST THIS AFTERNOON FOR AKZ017-022-023-
     025.
         WIND ADVISORY UNTIL 9 PM AKST THIS EVENING FOR AKZ018-019.
MARINE...GALE WARNING FOR PKZ012-022-051-052. 
         SMALL CRAFT ADVISORY FOR PKZ011-013-021-031-032-042-043. 
         SMALL CRAFT ADVISORY DUE TO SEAS FOR PKZ041. 

&&

$$

RWT/BEZENEK