Gale Warning 90, NWS Juneau, AK

SOUTHEAST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE JUNEAU AK
420 PM AKST SAT FEB 8 2014

.SHORT TERM...HIGH PRESSURE REMAINS THE DOMINATE FEATURE OVER
SOUTHEAST ALASKA FOR THE NEXT 24 HOURS. THIS HAS LED TO ANOTHER
DRY AND GENERALLY SUNNY DAY WITH SOME THIN HIGH CLOUDS STREAMING
OVER THE NORTHERN PANHANDLE. THE CLOUDS ARE IN ASSOCIATION WITH
AN UPPER LEVEL TROUGH DROPPING SOUTH FROM THE YUKON. THE UPPER
TROUGH WILL MOVE SOUTH INTO THE NORTHEASTERN GULF THIS EVENING
AND LEAD TO THE DEVELOPMENT OF A WEAK SURFACE LOW. THIS LOW
PRESSURE SYSTEM WILL HAVE LITTLE IMPACT PRECIPITATION WISE BUT
WILL KEEP MORE EXTENSIVE MID AND HIGH CLOUD COVER OVER THE
NORTHERN GULF COAST. SURFACE PRESSURE WILL BEGIN TO LOWER OVER
THE FAR SOUTHEAST GULF ON SUNDAY AFTERNOON AS A WAVE OVER THE
NORTHEAST PACIFIC BEGINS TO MOVE NORTH.

WIND WILL BE THE MAIN CONCERN FOR TONIGHT AND SUNDAY. THE
PRESSURE GRADIENT WILL BE GRADUALLY TIGHTENING AS HIGH PRESSURE
CONTINUES TO GRADUALLY BUILD OVER THE YUKON AND THE WEAK SURFACE
LOW FORMS OVER THE NORTHEAST GULF. THIS WILL LEAD TO INCREASING
OUTFLOW WINDS AND IN THE INNER CHANNELS. EXPECT GALE FORCE WINDS
TO SPREAD INTO SOUTHERN LYNN AND STEPHENS PASSAGE DURING THE DAY
ON SUNDAY WITH SMALL CRAFT WINDS IN A MAJORITY OF THE OTHER INNER
CHANNELS. DUE TO THE STRENGTHENING OUTFLOW HAVE INCLUDED A STRONG
WIND HEADLINE FOR DOWNTOWN JUNEAU AND DOUGLAS STARTING LATER THIS
EVENING AND CONTINUING THROUGH TOMORROW WITH GUSTS AROUND 40 MPH.
STRONG WIND HEADLINES ALSO IN THIS PACKAGE FOR SKAGWAY AND THE
HAINES AREA NEAR LYNN CANAL.

EXPECT HIGH THIN CLOUDS TO REMAIN OVER THE NORTHERN PANHANDLE
THROUGH SUNDAY WITH FILTERED SUNSHINE DURING THE DAYTIME HOURS.
WHILE THERE WILL BE A HIGH OVERCAST AT TIMES OPTED TO KEEP WORDING
AS EITHER PARTLY TO MOSTLY CLOUDY. TEMPERATURES WILL BE SIMILAR TO
WHAT HAS BEEN SEEN FOR THE LAST FEW DAYS. ALTHOUGH INCREASED
OUTFLOW WINDS WILL KEEP SOME AREAS A LITTLE WARMER THAN THE PAST
COUPLE NIGHTS. ANOTHER FACTOR THAT MAY KEEP TEMPERATURES A COUPLE
DEGREES WARMER OVER THE NORTHERN PANHANDLE IS THE HIGH THIN CLOUDS
BUT DON'T EXPECT THIS TO INHIBIT TEMPERATURES FROM FALLING TOO
MUCH. HIGHS ON SUNDAY WILL RANGE FROM THE UPPER TEENS IN HAINES
AND SKAGWAY TO AROUND FREEZING IN THE SOUTHERN PANHANDLE. HAVE
EXTENDED THE WIND CHILL ADVISORY FOR WHITE PASS THROUGH 4 PM
SUNDAY WITH WINDS CONTINUING TO BLOW AND A SMALL DIURNAL CHANGE IN
TEMPERATURE FOR SUNDAY.

USED A BLEND OF THE 12Z NAM/00Z ECMWF FOR UPDATES TO THE
FORECAST. NUDGED WIND IN THE GULF TOWARD THE NAM TO BETTER CAPTURE
OUTFLOW WINDS. FORECASTER CONFIDENCE IS ABOVE AVERAGE ON CONTINUED
WINDY AND DRY CONDITIONS FOR THE PANHANDLE THROUGH LATE SUNDAY
AFTERNOON.

&&

.LONG TERM...LOW MOVING ACROSS THE NORTH PACIFIC TOWARD HAIDA GWAII
SUNDAY NIGHT LOOKS TO INCREASE PRESSURE GRADIENT WITH THE HIGH
PRESSURE BUILDING IN THE YUKON. THEREFORE EXPECT OUTFLOW WINDS TO
INCREASE SUNDAY NIGHT AND MONDAY. THIS WILL ALSO BE A PRIME SET UP
FOR A TAKU WIND EVENT. STRONG WINDS IN THE TAKU WIND AREA WILL
INCREASE THROUGH SUNDAY NIGHT TO MEET THE WATCH CRITERIA OF 60
MPH MONDAY MORNING AND CONTINUE THROUGH MONDAY EVENING. EXPECT
PEAK WINDS TO START LATE MONDAY MORNING...BUT THIS TIMING MAY BE
ADJUSTED.

OTHER OUTFLOW AREAS WILL BE QUITE STRONG TOO. HAVE NORTHERN LYNN
CANAL INCREASING TO STORM FORCE 50 KT ON MONDAY. MOST ZONES HAVE A
MENTION OF GUSTS AROUND 40 MPH ON MONDAY...KEEP IN MIND THESE WILL
BE GREATEST NEAR THOSE INTERIOR PASSES AND INSIDE WATERS SUCH AS
LYNN CANAL/CROSS SOUND.

THE AFOREMENTIONED LOW WILL MOVE NEAR HAIDA GWAII AND DIXON
ENTRANCE MONDAY MORNING. THIS WILL BRING SNOW TO THE SOUTHERN
PANHANDLE. THE KETCHIKAN AREA COULD SEE AROUND 3 INCHES DURING THE
DAY MONDAY AND ANOTHER 1-2 INCHES MONDAY NIGHT. FOR THE REST OF
THE PANHANDLE THE NEXT BEST CHANCE OF PRECIP LOOKS TO BE LATE IN
THE WEEK...THURDAY/FRIDAY. HOWEVER THE GFS IS A LOT WEAKER WITH
THIS SYSTEM AND DOES NOT BRING THE SNOW INLAND AS MUCH AS THE
ECMWF. THEREFORE HAVE LIMITED THE POPS TO LIKELY FOR NOW.

COLD WEATHER DOESN'T LOOK TO END IN THIS FORECAST PERIOD...IN
FACT IT LOOKS TO GET STEADILY COLDER THROUGH TUESDAY. THEN A SLOW
WARM UP IS EXPECTED GOING INTO NEXT WEEKEND...BUT STILL PLENTY
COLD ENOUGH FOR ANY PRECIPITATION TO FALL AS SNOW...OR AT LEAST A
MIX OVER THE SOUTHERN AREAS.

MODELS ARE IN GOOD AGREEMENT IN THE NEAR TERM FOR THE
TIGHT PRESSURE GRADIENT. USED A BLEND OF AVAILABLE MODELS WITH AN
EMPHASIS ON THE ECMWF. BEYOND THAT TIME-FRAME THE MODELS START TO
DIVERGE...SO WENT WITH WPC NATIONAL GUIDANCE WHICH WAS LARGELY
ECMWF ENSEMBLES.

&&

.AJK WATCHES/WARNINGS/ADVISORIES...
PUBLIC...STRONG WIND FROM MIDNIGHT AKST TONIGHT THROUGH SUNDAY AFTERNOON
     FOR AKZ025.
         STRONG WIND THROUGH SUNDAY AFTERNOON FOR AKZ018-019.
         WIND CHILL ADVISORY UNTIL 4 PM AKST SUNDAY FOR AKZ018.
MARINE...HEAVY FREEZING SPRAY WARNING FOR PKZ012.
         GALE WARNING FOR PKZ012-013-022-031.
         SMALL CRAFT ADVISORY FOR PKZ011-021-032>035-043-051-052.

&&

TPS/FERRIN