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FXAK67 PAJK 020049
AFDAJK

SOUTHEAST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE JUNEAU AK
349 PM AKST SUN FEB 1 2015

.SHORT TERM...SHORTWAVE THAT PASSED OVER SOUTHEAST ALASKA
YESTERDAY WAS WEAKER THAN EXPECTED, AND THE CRITICAL LEVEL THAT
RESULTED WAS PERHAPS A LITTLE TOO HIGH IN THE ATMOSPHERE FOR THE
CROSS-BARRIER WINDS AT RIDGETOP LEVEL TO REFLECT EFFICIENTLY BACK
TO THE SURFACE. HOWEVER, TODAY`S SHORT-WAVE, THE SECOND AND
STRONGER APPEARS TO BE DOING THE DEED. MOUNTAIN WAVE WINDS ARE
REACHING DOUGLAS AND DOWNTOWN JUNEAU WITH GUSTS FROM 50 TO 70 MPH
THIS AFTERNOON. EVEN LEMON CREEK AND THE AIRPORT HAVE APPROACHED
GUSTS TO 35 MPH. THE CRITICAL LEVEL SHOULD PASS JUNEAU ON ITS WAY
SOUTHEAST THIS EVENING, BUT MOMENTUM MAY CARRY HIGH WIND GUSTS
OVERNIGHT. HOWEVER, SHOULD WIND SPEEDS START TO DIMINISH LATE THIS
EVENING, THE WE MAY BE ABLE TO PULL THE HIGH WIND WARNING EARLY.
HOWEVER, OWING TO THE CROSS BARRIER FLOW, STRONG WINDS SHOULD
CONTINUE THROUGH DOWNTOWN JUNEAU/DOUGLAS WELL INTO TOMORROW, BUT
NOT BE SPEEDY ENOUGH TO MANDATE A HIGH WIND WARNING.

TODAY, THERE DOES SEEM TO BE AGREEMENT THAT ALL THE GRADIENTS WILL
GRADUALLY RELAX OVERNIGHT AND INTO TOMORROW, SO THIS WAS A DAY
DEDICATED TO STREAMLINING THIS STORYLINE. STORM FORCE WINDS SHOULD
MORPH TO GALE BY EARLY MONDAY MORNING. AND MANY GALES OF TONIGHT
WILL BE STEADILY RELAXING INTO SMALL CRAFT BY MONDAY. EVEN SO,
WINDS AT SKAGWAY AND ALONG THE KLONDIKE SHOULD EXTEND WELL INTO
MONDAY WITH GUSTS TO 55 MPH TONIGHT AND 45 MPH MONDAY. THIS SHOULD
BE PLENTY TO CONTINUE BLOWING SNOW VERY LOW VISIBILITY NEAR WHITE
PASS. IN ADDITION VERY COLD TEMPERATURES WILL KEEP WIND CHILLS
APPROACHING 40 BELOW ZERO THROUGH MOST OF MONDAY. THUS THE WIND
CHILL ADVISORY WILL BE EXTENDED THROUGH 3 PM MONDAY. ALLOWED
STRONG WINDS TO CONTINUE NEAR LYNN CANAL SOUTH OF HAINES, AT LEAST
THROUGH THE PERIOD OF STORM FORCE THROUGH LYNN CANAL, BUT COULD
NOT JUSTIFY KEEPING IT ANY FARTHER IN LIGHT OF HOW HAINES AIRPORT
HAS BEHAVED TODAY. IT SEEMS THE GRADIENT IS SUCH THAT HAINES IS
BEING LESS AFFECTED THAN SKAGWAY/ELDRED ROCK, PROBABLY IN A MANNER
THAT OUR HIGHEST RESOLUTION MODELS CANNOT REPRESENT.

FINALLY OFFSHORE WINDS ACROSS THE SOUTHERN PANHANDLE HAVE
INHIBITED PRECIPITATION. SOME BANDS HAVE MADE IT TO KETCHIKAN AND
KLAWOCK BUT THEY APPEAR TO BE LIGHT. KLAWOCK HAS INDICATED SOME
SNOW, THUS DID KEEP SNOW LEVEL AT ZERO IN THE NORTHERN MOST
PORTIONS OF THIS VERY SOUTHERN PRECIPITATION EVENT. STEWARD HAS
NOT INDICATED ANY PRECIPITATION THUS FAR TODAY, SO BACKED OFF FROM
CATEGORICAL TO LIKELY. STILL THEY COULD SEE UP TO 3 INCHES IN THE
NEXT 24 HOURS OF SNOW.

PREFERRED GEM AND HIGH RES ARW TO USE FOR ANY CHANGES. FORECAST
CONFIDENCE GOOD. TEMPERATURES PROBABLY THE LOWEST CONFIDENCE. HIGH
TEMPERATURES TOMORROW MAY BE COOLER THAN TODAY, AS WINDS WILL BE A
TOUCH LIGHTER. BUT CONFIDENCE NOT GREAT; THEY MAY NEED TO BE
RAISED.

.LONG TERM...WITH EXCEPTION OF THE EXTENSION OF THE WINTER WEATHER
ADVISORY FOR WHITE PASS REGION THROUGH MONDAY AFTERNOON THE
FORECAST FOR THE FIRST PART OF THE WEEK STILL ON TRACK. WINDS
WILL SUBSIDE THROUGH MONDAY AND MONDAY NIGHT AS THE HIGH PRESSURE
SLIDES SOUTHEAST TOWARDS THE UPPER MID WEST OF THE CONUS. THE
BROAD AREA OF LOW PRESSURE SOUTH OF THE EASTERN ALEUTIANS INTO THE
SOUTHWEST GULF OF ALASKA IS PERSISTING. HEADED INTO MIDWEEK A VIGOROUS
SHORTWAVE MOVING FROM THE RUSSIAN ARCTIC TO THE AND ALASKA ARCTIC
WILL BE USHERING IN A SIBERIA HIGH PRESSURE SYSTEM. THE SHORT WAVE
WITH THE COLD ARCTIC AIR WILL BE SLIDING SOUTH INTO THE NORTHERN
PANHANDLE THURSDAY NIGHT INTO FRIDAY. BELIEVE THE HIGH TEMPERATURE FRIDAY
WILL BE EARLY IN THE DAY WITH TEMPERATURES STAYING STEADY TO
SLOWLY FALLING DURING THE DAY TIME. MEANWHILE SOUTHERN PANHANDLE
TEMPERATURES NOT CHANGING MUCH.

WHILE THE COLD TEMPERATURES ARE MOVING TO THE AREA EXPECT A STRONG
NORTH TO NORTHEAST PRESSURE GRADIENT AT THE END OF THE WEEK SO
MARINES AND NORTHERN ZONES TO SEE GALE TO STORM FORCE WIND. STRONG
WIND HEADLINES FOR SOME AREAS AND POTENTIAL GROUND BLIZZARD
CONDITIONS AGAIN FOR THE WHITE PASS AREA. THE LONGER RANGE MODELS
GENERALLY AGREE THAT THERE SOME SORT OF LOW MOVING NORTHWARD INT
EH UPPER LEVEL FLOW INTO THE SOUTHERN/CENTRAL PANHANDLE REGION
ABOUT THE SAME TIME OR JUST AFTER THE COLD AIR GETS POSITIONS.
DEPENDING ON THE TRACK A SOLID OVERRUNNING SNOW EVENT COULD
DEVELOP FOR THE NORTHERN PANHANDLE LATE FRIDAY INTO SATURDAY. WILL
CONTINUE TO MONITOR THIS SITUATION. FORECAST CONFIDENCE IS GOOD
INTO THE FIRST HALF OF THE WEEK AND THEN AVERAGE OR SLIGHTLY BELOW
HEADED INTO NEXT WEEKEND.



&&

.AJK WATCHES/WARNINGS/ADVISORIES...
PUBLIC...HIGH WIND WARNING UNTIL 6 AM AKST MONDAY FOR AKZ025.
         STRONG WIND UNTIL 3 AM AKST MONDAY FOR AKZ019.
         WINTER WEATHER ADVISORY UNTIL 3 PM AKST MONDAY FOR AKZ018.
MARINE...STORM WARNING FOR PKZ012.
         GALE WARNING FOR PKZ011-013-021-022-031-032-035-043-051.
         SMALL CRAFT ADVISORY FOR PKZ033-034-036-041-042-052.

&&

$$

JWA/BEZENEK

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