Small Craft Advisory 732, NWS Juneau, AK

SOUTHEAST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE JUNEAU AK
330 PM AKST WED NOV 16 2011

.SHORT TERM...980 MB LOW 200 NM S OF PACV IS TRACKING SSE IN A
CYCLONIC INTERACTION WITH A SECOND 980 MB LOW THAT IS ABOUT 100 NM
S OF PAKT AT THIS TIME. BOTH OF THESE LOWS WILL WEAKEN TONIGHT
LEAVING A BROAD AND RELATIVELY WEAK LOW PRESSURE FIELD OVER THE
SOUTHERN HALF OF THE PANHANDLE EARLY THU.

 THE GOES IR IS CONSISTENT WITH THE FIRST LOW BEING A WEAKENING
PARENT FEATURE WITH THE SECOND LOW A TRAVELING WV ON THE
ASSOCIATED FRONTAL BOUNDARY THAT IS APPROACHING THE SRN PNHDL FM
THE S.

 THE ARCTIC OUTBREAK HAS MOVED INTO THE NRN PANHANDLE. AN EARLY
SIGN IN THE NRN PANHANDLE SHOWED UP AT PRT WITH AN 8F TEMPERATURE
FALL FROM 15Z TO 17Z. A BLIZZARD IS OCCURRING IN THE PAHN VCNTY
THAT IS THE RESULT OF A SECTION OF THE FRONTAL BNRY QSTNRY INVOF
PAHN, AS WELL AS THE ARCTIC AMS MOVING UNDERNEATH AND LIFTING THE
AIR COLUMN.

&&

.LONG TERM...MODELS ARE IN FAIR AGREEMENT THROUGHOUT THE LONG
TERM FORECAST PERIODS. REFRESHED THE INHERITED FORECAST PACKAGE
WITH THE ECMWF TO MAINTAIN A MAXIMUM CONSISTENCY. THE LOW PRESSURE
SYSTEM NEAR HAIDA GWAII WILL WEAKEN AND EXIT TO THE SOUTH THROUGH
FRIDAY WHILE ARCTIC HIGH MAINTAINS ITS TERRITORY NORTH OF THE
PANHANDLE. THE COLD AIR OUTBREAK WILL CONTINUE ACROSS THE NORTHERN
PANHANDLE THROUGH FRIDAY WITH STRONG NORTHERLY PRESSURE GRADIENT.

 STORM FORCE WINDS WILL EASE DOWN TO GALE OVER NORTHERN LYNN
CANAL TOWARDS WEEKEND WITH FREEZING SPRAY ACROSS THE NORTHERN
INNER CHANNELS. STRONG GUSTY WINDS WILL CONTINUE TO AFFECT
YAKUTAT...HAINES AND SKAGWAY AREAS ON THURSDAY NIGHT AND LAST A
BIT LONGER FOR SKAGWAY THROUGH FRIDAY MORNING. MARGINAL TAKU WIND
IS STILL IMPOSING DOWNTOWN JUNEAU AND DOUGLAS ON THURSDAY NIGHT.
GENERALLY DRY WEATHER WILL CONTINUE AND RADIATIONAL COOLING WILL
ENHANCE THE OVERNIGHT LOWS ACROSS THE FORECAST DOMAIN THROUGH
EARLY SUNDAY MORNING. WIND CHILL VALUES ARE EXPECTED TO DROP 20 TO
25 BELOW OVER NORTHERN MOST PANHANDLE THROUGH FRIDAY NIGHT.

 A DEVELOPING LOW IN THE NORTHERN GULF LATE SATURDAY NIGHT WILL
PUSH A FRONTAL PASSAGE INTO THE EASTERN GULF EARLY SUNDAY MORNING.
THE FRONTAL BOUNDARY WILL MOVE ONSHORE OVER THE PANHANDLE BY
MIDDAY SUNDAY AND REMAIN OVER THE AREA THROUGH TUESDAY. THE
EMBEDDED AIR MASS LOOKS RELATIVELY WARM...BUT THE RESIDING
TEMPERATURES WILL BE COLD ENOUGH FROM THE ARCTIC OUTBREAK FOR SNOW
ACROSS THE NORTHERN ZONES.

&&

.AJK WATCHES/WARNINGS/ADVISORIES...
PUBLIC...STRONG WIND FROM 9 PM THIS EVENING TO 3 AM AKST THURSDAY FOR
     AKZ025.
         STRONG WIND FROM 3 AM AKST THURSDAY THROUGH THURSDAY MORNING FOR
     AKZ022.
         STRONG WIND UNTIL 3 AM AKST THURSDAY FOR AKZ020.
         STRONG WIND FROM THURSDAY AFTERNOON THROUGH LATE THURSDAY NIGHT
     FOR AKZ019.
         BLIZZARD WARNING UNTIL 9 PM AKST THIS EVENING FOR AKZ019.
         STRONG WIND THROUGH FRIDAY AFTERNOON FOR AKZ018.
         STRONG WIND THROUGH LATE THURSDAY NIGHT FOR AKZ017.
MARINE...STORM WARNING FOR PKZ011-012-051-053.
         GALE WARNING FOR PKZ013-021-022-031-032-041>043.
         SMALL CRAFT ADVISORY FOR PKZ033>036-052.

&&

JBT/AHN