Gale Warning 100, NWS Juneau, AK

SOUTHEAST ALASKA FORECAST DISCUSSION
1100 AM AST TUE FEB 27 2007

.SHORT RANGE...THE PERSISTENT COLD AND WINDY CONDITIONS WILL
CONTINUE THROUGH WED AFTERNOON AS THE 1035MB HIGH OVER THE YUKON
WILL NOT MOVE THROUGH THE PERIOD. THIS WILL KEEP THE VERY WINDY
CONDITIONS OVER THE NORTHERN GULF AND NORTH INNER CHANNELS
THROUGH WED AFTERNOON WITH THE PRESSURE GRADIENT REMAINING TO BE
VERY STRONG BETWEEN THE INTERIOR AND THE PANHANDLE. WITH THAT
SAID WILL CONTINUE TO HAVE THE WIND ADVSIORIES THROUGH WED
AFTERNOON FOR ZONES 17 18 AND 19 AND THE WIND CHILL FOR ALONG THE
KLONDIKE HIGHWAY. WILL ALSO CONTINUE THE MODERATE TO HEAVY
FREEZING SPRAY OVER THE NORTHERN WATERS ALONG WITH MAX GALES IN
LYNN CANAL AND SMALL CRAFTS IN OTHER NORTH/SOUTH CHANNELS WITH
HIGHER GUSTS OUT OF INTERIOR BAYS AND PASSES.

THE COLD TEMPS WILL ALSO CONTINUE THROUGH WED WITH TEMPS DROPPING
TO THE SINGLE DIGITS OVER THE NORTHERN HALF OF THE FORECAST AREA
AND IN THE TEENS FOR THE REST OF THE SOUTHERN AREAS. PAYA WILL
SEE THE LOWS DROP INTO NEGATIVE DIGITS AGAIN TONIGHT AS THE SKIES
WILL REMAIN MOSTLY CLEAR TONIGHT. THE REST OF THE PANHANDLE WILL
SEE PARTLY TO MOSTLY CLEAR SKIES THROUGH TODAY AND MOST OF THE
NORTHERN HALF WILL CLEAR ALL THE WAY OUT TONIGHT AS THE UPPER
TROF SLOWLY MOVING THROUGH THE AREA ATTM WILL INCREASE THE
OFFSHORE FLOW TONIGHT. THE SOUTHERN AREAS WILL CONTINUE TO BE
MOSTLY CLOUDY THROUGH TODAY AND INTO THE EVENING HOURS BUT AS THE
TROF CONTINUES TO DRIFT EAST THEY WILL BEGIN TO SEE DECREASING
CLOUDS EXCEPT FOR HYDER AS THEY WILL REMAIN CLOUDY THROUGH
TONIGHT.

THERE IS LIGHT SNOW FALLING OVER ZONES 26 AND 29 AND THINK THIS
WILL CONTINUE FOR ZONE 26 THROUGH MIDNIGHT AND THEN BECOME PARTLY
CLOUDY WHILE ZONE 29 WILL SEE LIGHT SNOW THROUGH THE NIGHT BUT BY
THE MORNING WILL SEE THE CLOUDS DECREASE. AMOUNTS WILL NOT BE
MUCH BUT 1 TO 2 INCHES CAN BE EXPECTED THROUGH TONIGHT.

FOR WEDNESDAY...WINDY AND COLD WILL CONTINUE WITH MOSTLY CLEAR
SKIES OVER THE NORTHERN HALF OF THE PANHANDLE...THE SOUTHERN HALF
WILL SEE SOME CLOUDS BUT THERE WILL BE SUNNY BREAKS. SOUTHEAST
ALASKA WILL INCREASE THE ONSHORE FLOW ALOFT AS THE UPPER LOW OVER
THE YUKON BEGINS TO DROP SOUTH AND ALLOWS THE UPPER FLOW PATTERN
TO BECOME MORE ZONAL. SO SOME PLACES WILL SEE INCREASING CLOUDS
THROUGH THE DAY BUT FOR THE MOST PART IT SHOULD BE A VERY NICE
DAY ACROSS THE FORECAST AREA.

.LONG RANGE...
ALL MODELS REVIEWED INSIST AFTER SEVERAL RUNS THAT A MAJOR UPPER
LOW/TROF WILL DIG INTO THE EASTERN GULF BY 00Z FRI. 12Z GFS-190
PREDICTS THAT THE UPPER LOW CENTER WILL BE OVER PAYA 00Z FRI WITH
-41C @500 MB. ONLY 12Z UKMET IS OUTLIER...OTHERWISE GOOD
AGREEMENT WITH GFS-190 WHICH IS ACCEPTED THAT THE UPPER SYSTEM
SUPPORTS 997 MB SFC LOW JUST OFF DIXON ENTRANCE THU AFTERNOON.
N-S SURFACE PRES GRADIENTS WILL BUILD TO VERY STRONG AS THE SFC
LOW CENTER MOVES OVER THE SOUTHERN PANHANDLE. WE MUST ALSO
CONSIDER HEAVY SNOW FOR SOME AREAS OF THE SOUTHERN PANHANDLE WITH
THE TRACK OF THIS FIRST LOW. WE WILL PROBABLY HAVE TO ISSUE A
WATCH FOR AT LEAST ZONE 29 AND POSSIBLY 26 27 AND 28.

A DEEPER SFC LOW WILL DEVELOP TO THE SW OF THE FIRST ONE THU
NIGHT AND THE GFS IS AS GOOD AS ANY MODEL MOVING THE SECOND LOW
INTO THE CHARLOTTES BY FRI AFTERNOON. EXPECT ONLY MINOR CHANGES
TO MEDIUM RANGE GRIDS BEYOND FRI AS ARCTIC HIGH PRES PERSISTS
OVER THE YUKON AND THE ARCTIC FRONT REMAINS TO THE SOUTH.
CONFIDENCE HIGH. BRRRRRR.

.AJK...WATCHES/WARNINGS/ADVISORIES
PUBLIC...WIND ADV...AKZ17 18 19
         WIND CHILL ADV...AKZ19 ALONG THE KLONDIKE

MARINE...GALE...PKZ11 12 13
         HEAVY FREEZING SPRAY...PKZ11 12 13
         SCA...ALL OTHER MARINE ZONES

ABJ/JC