Area Forecast Discussion - Southeastern

FXAK67 PAJK 231424
AFDAJK

SOUTHEAST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE JUNEAU AK
524 AM AKST MON NOV 23 2009
.SHORT TERM...A STRONG LOW JUST E OF KODIAK WILL MOVE TO JUST S OF
THE KENAI PENINSULA THIS AFTERNOON...THEN CONTINUE N BUT DISSIPATE
OVER SOUTH-CENTRAL AK BY LATE TONIGHT. A STRONG OCCLUDED FRONT
OVER THE ERN GULF WILL MOVE THRU SE ALASKA TODAY.

MAIN FORECAST CONCERNS WILL BE WINDS AND SNOW AMOUNTS. AS FOR
WINDS...HAVE ADVY LEVEL GUSTS OVER THE SRN AREA EARLY THIS
MORNING. EXPECT THOSE TO CONTINUE UNTIL THE FRONT MOVES THRU THERE
BY MID-MORNING...WHEN WINDS WILL DIMINISH. EXPECT GALE TO STORM
FORCE WINDS AHEAD OF THE FRONT OVER THE ERN GULF...AND GALES OVER
THE SRN AND WRN INNER CHANNELS...WITH SCA LEVEL WINDS OVER THE NRN
AND ERN INNER CHANNELS...UNTIL THE FRONT MOVES THRU WHEN WINDS
SHOULD DROP TO SCA LEVELS OR LESS. AFTER FRONT MOVES PAST THE PAGY
AREA LATE THIS AFTERNOON...WINDS WILL PICK UP AND ADVY LEVEL SSW
WINDS ARE LIKELY THERE TONIGHT.

AS FOR SNOWFALL...LIFT IS STRONG AND WELL LOCATED IN THE DENDRITE
GROWTH ZONE. LIMITING FACTOR IS THE ELY FLOW SFC-5000 FEET...BUT
THIS WILL WEAKEN AS THE STRONGEST PRE-FRONTAL UVVS ARRIVE THIS
MORNING. DEEPEST COLD AIR TO OVERRUN WILL BE AROUND HAINES...WHERE A
WINTER STORM WARNING WAS ISSUED FOR 4 TO 8 INCHES OF SNOW TODAY.
FURTHER S...FOR PAGS/PAOH/PAJN...EXPECT 3 TO 5 INCHES OF SNOW
BEFORE IT MIXES WITH THEN CHANGES TO RAIN IN THE AFTERNOON. HAVE
KEPT THE WINTER WX ADVYS GOING THERE. ELSEWHERE...SHOULD SEE ABOUT
2 TO 4 INCHES OF SNOW AROUND PAYA AND 3 TO 6 INCHES AROUND HYDER
BEFORE CHANGING TO RAIN THIS AFTERNOON. ALSO...PAGY WILL LIKELY
GET 1 TO 3 INCHES OF SNOW...WHICH IS BELOW ADVY LEVELS SO
CANCELLED THEIR WINTER WX ADVY. OTHER AREAS SHOULD BE MAINLY RAIN
WITH ANY SNOW AT THE ONSET QUICKLY CHANGING TO RAIN.

ONCE THE FRONT MOVES THRU...SHOULD SEE SHOWERS MOVE IN THIS
AFTERNOON OVER THE S AND THIS EVENING OVER THE N. POST-FRONTAL
MILD MARITIME AIRMASS WILL KEEP SNOW LEVELS WELL ABOVE SEA LEVEL
SO ALL RAIN SHOWERS MENTIONED IN THE ZONES TONIGHT. THERE MAY BE
SOME TSTMS OVER THE SE GULF AND ADJACENT COASTAL AREA THIS
AFTERNOON AS COLDEST AIR ALOFT MOVES IN WITH CAPE VALUES NEAR 300 
J/KG...BUT LACK OF ANY STRONG UPPER VORT MAXIMA OR SFC TROF WILL
KEEP THEM ISOLATED AT MOST.


&&
.LONG TERM...A DOUBLE LOW FEATURE MOVING INTO THE CENTRAL GULF
TUESDAY AND WEDNESDAY. THE FIRST OF THE LOWS WILL MOVE NORTH OVER
EASTER GULF SPREADING IS FRONTAL BAND ALON AND ONSHORE SOUTHEAST
ALASKA FOR TUESDAY AFTERNOON. THE ORIENTATION AND STRENGTH OF THE
FRONT LOOKS LIKE IT COULD BE STORM FORCE FOR THE COASTAL MARINE
ZONES SOUTH OF CROSS SOUND. THERE IS ALSO THE POSSIBILITY OF
ANOTHER ROUND OF WIND ADVISORIES FOR THE SOUTHWEST COASTAL ZONES
AS WELL. THE RAIN WILL SPREAD IN THROUGH TUESDAY AND THE FRONT
SHOULD BE THROUGH BY LATE TUESDAY NIGHT. THE SECOND LOW WILL
CONTINUE TO MOVE NORTHEAST AND SHOULD SPREAD ACROSS WEDNESDAY A
THE UPPER LEVEL TROUGH WILL BE BEING LIFTED NORTHEAST AND OUT OF
THE GULF BY RIDGE MOVING INTO WESTERN GULF. EXPECT ONE MORE QUICK
TROUGH UNDER AN UPPER TROUGH TO MOVE THROUGH THE PANHANDLE
WEDNESDAY NIGHT. AT THE MOMENT THERE LOOKS TO BE RIDGE MOVING
ACROSS THE EASTERN GULF AND SOUTHEAST ALASKA FOR THE THANKSGIVING
HOLIDAY BUT ANOTHER STRONG WINDY FRONT MOVING INTO THE THE CENTRAL
GULF COAST THURSDAY NIGHT AND THE REMAINDER OF THE AREA FRIDAY.

MODELS THROUGH THE MID WEEK IN FAIR AGREEMENT AND THE GRID
ADJUSTMENTS WERE WITH THE GFS AND ECMWF BLEND THROUGH EARLY
THURSDAY. LONGER RANGE PORTIONS OF THE FORECAST PERIODS WERE
MINIMALLY ADJUSTED AS THE DISCREPANCIES AT THAT TIME FRAME SO
DECIDED TO CONTINUE WITH THE CURRENT FORECAST PACKAGE. FORECAST
FOR THE NEXT WEEKEND COULD BE SEEING A CHANGE IF THEY CONTINUE TO
SHOW A NEW LARGE LOW MOVING IN TO THE GULF FROM THE NORTHERN
PACIFIC OCEAN.



.AJK WATCHES/WARNINGS/ADVISORIES...
PUBLIC...WIND ADVISORY UNTIL 9 AM AKST THIS MORNING FOR AKZ023-027>029.
         WINTER WEATHER ADVISORY UNTIL 3 PM AKST THIS AFTERNOON FOR 
     AKZ020-021-025.
         WINTER STORM WARNING UNTIL 6 PM AKST THIS EVENING FOR AKZ019.
         WIND ADVISORY FROM 6 PM THIS EVENING TO 3 AM AKST TUESDAY FOR 
     AKZ018.
MARINE...STORM WARNING FOR PKZ043-051-052. 
         GALE WARNING FOR PKZ021-022-032>036-041-042. 
         SMALL CRAFT ADVISORY FOR PKZ011>013-031. 

&&

$$

RWT/BEZENEK