High Wind Warning 11, NWS Juneau, AK

SOUTHEAST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE JUNEAU AK
102 PM AKDT WED SEP 22 2010

.SHORT TERM...PARTLY CLOUDY SKIES CONTINUE ACROSS THE PANHANDLE
EARLY THIS AFTERNOON AS THE CURRENT SATELLITE REVEALS THE MARINE
STRATUS REMAINING WELL WEST OF THE PANHANDLE AND IN THE CENTRAL
GULF. A 985 MB SURFACE LOW NOW NEAR 50N 142W WILL SLOWLY WEAKEN
AND MOVE TO THE NORTHEAST OVER THE NEXT DAY AND ITS ASSOCIATED
FRONTAL BOUNDARY...LOCALLY WINDY CONDITIONS AND RAINFALL WILL BE
THE MAIN FORECAST PROBLEM THROUGH THE SHORT TERM PERIOD. USED A
50/50 BLEND OF THE 12Z GFS AND UKMET FOR THE SHORT TERM PERIOD AS
BOTH THESE MODELS INITIALIZED THE SURFACE LOW NEAR 50N 142W THE
BEST WITH THE 12Z NAM BEING TO SLOW AND WEAK. FORECAST CONFIDENCE
IS ABOVE AVERAGE THROUGH THE SHORT TERM PERIOD.

 FOR TONIGHT WILL SEE PARTLY TO MOSTLY CLOUDY SKIES ACROSS THE
MAJORITY OF THE PANHANDLE WITH THE 985 MB SURFACE LOW MOVING TO
100 NM SOUTHWEST OF THE CHARLOTTES BY LATE TONIGHT WITH ITS
ASSOCIATED FRONTAL BOUNDARY MOVING INTO DIXON ENTRANCE.
UNFORTUNATELY...THE RAIN BEGINS TO MOVE ACROSS THE PANHANDLE
EARLY THURSDAY MORNING AND KEPT RAIN LIKELY FOR AKZ027 LATE
TONIGHT. WILL SEE LOCALLY WINDY CONDITIONS ACROSS THE SOUTHERN
OUTER COAST AND SOUTHERN PANHANDLE TONIGHT AS THE SOUTHEASTERLY
LLJ 850 MB WINDS INCREASE TO NEAR 45 KNOTS. COULD SEE AN ISOLATED
WIND ADVY GUSTS EARLY ON THURSDAY NEAR PAHY...BUT THERE IS A MUCH
STRONGER STORM AT THE BEGINNING OF LONG TERM AND HAVE STATEMENTS
OUT FOR THAT. THE INCREASED CLOUD COVER TONIGHT WILL KEEP MOST
AREAS FROM DROPPING TO FREEZING WITH LOW TEMPERATURES IN THE MID
30S TO LOW 40S.

 ON THURSDAY WILL SEE RAIN SPREAD NORTHWARD ACROSS THE SOUTHERN
AND CENTRAL PANHANDLE THROUGH THE DAY. THE MID LEVEL FRONTAL BAND
WILL SHEAR APART AS IT MOVES NORTHWARD AND SO EXPECT PRECIP
AMOUNTS TO REMAIN LIGHT. ALSO THE EASTERLY SURFACE FLOW AND
SOUTHEASTERLY MID LEVEL FLOW WILL BRING IN DRIER AIR FROM BRITISH
COLUMBIA AND THIS WILL LIMIT PRECIP AMOUNTS NORTH OF FREDERICK
SOUND THROUGH TOMORROW AFTERNOON. BREEZY CONDITIONS WILL CONTINUE
THROUGH THE DAY TOMORROW ALONG THE OUTER COAST AND SOUTHERN
PANHANDLE WITH A STRONG SOUTHEASTERLY SURFACE PRESSURE GRADIENT
AND 850 MB LLJ WINDS NEAR 40 KNOTS. CONCERNED COULD SEE GALE
FORCE WINDS IN CLARENCE STRAIT NEAR THE CHANNELED TERRAIN BUT
WILL WAIT FOR NEWER MODEL RUNS TO SEE HOW QUICKLY THEY SHEAR
APART THE MID LEVEL FRONTAL BOUNDARY TOMORROW. THE RAINFALL ON
THURSDAY WILL END THE ABNORMALLY DRY SEPTEMBER WEATHER PATTERN
ACROSS THE PANHANDLE.

.LONG TERM...MODELS HAVE COME INTO VERY GOOD AGREEMENT ON THE
STORM COMING IN FOR LATE WEEK. LOOKS LIKE A 945-950 MB LOW WILL
TRACK INTO THE S-CENTRAL GULF BY FRI MORNING...WITH A STRONG
OCCLUDED FRONT MOVING INTO THE SE GULF FRI MORNING...THEN N AND E
THRU THE AREA BY FRI EVENING. ALSO LOOKS LIKE THERE MAY BE ONE OR
MORE SECONDARY FRONTAL WRAPS MOVING ONSHORE FRI NIGHT INTO SAT
NIGHT. THIS WILL LIKELY BRING SEVERAL ROUNDS OF STRONG WINDS TO
THE AREA...WITH THE STRONGEST EXPECTED OVER THE SRN AREA AHEAD OF
THE FIRST FRONT FRI MORNING INTO AFTERNOON. 850 MB FLOW IS
FORECAST TO BE IN THE 85-95KT RANGE AHEAD OF THE INITIAL
FRONT...BUT WILL BE IN A WEAK WARM ADVECTION PATTERN AT THE SAME
TIME SO NOT AS MUCH WIND WILL TRANSLATE DOWN TO THE SFC AS USUALLY
OCCURS WITH 850 MB FLOW THAT STRONG. STILL...IT IS LOOKING LIKE A HIGH
WIND EVENT FOR ZONES 27 AND 28 FRI MORNING AND AFTERNOON...WITH
POTENTIAL FOR ADVY WINDS AROUND THE WARNING AREA AT THE SAME TIME.
WILL BE ISSUING A HIGH WIND WATCH FOR 15Z FRI TO 00Z SAT FOR ZONES
27 AND 28. WILL HOLD OFF ON ANY ADVYS FOR THE REMAINDER AS IT
WOULD BE A 4TH PERIOD STARTING TIME...BUT WILL REISSUE THE SPS FOR
THE ZONES OUTSIDE THE WATCH AREA. WILL ALSO ISSUE A MARINE WEATHER
STATEMENT FOR THE LARGE SEAS AND HIGH WINDS FOR THE SERN
GULF...AFTER A LONG PERIOD OF UNUSUALLY TRANQUIL WEATHER FOR THIS
TIME OF YEAR.

RAINFALL MAY BE LOCALLY HEAVY FRI WITH THE FIRST FRONT...ESPECIALLY
OVER THE SRN AREA. THERE MAY BE BURSTS OF HEAVIER RAIN WITH THE
SECONDARY FRONTAL WRAPS AS WELL FRI NIGHT INTO SAT NIGHT. GIVEN
HOW DRY IT HAS BEEN LATELY...DO NOT ANTICIPATE ANY FLOODING ISSUES
THOUGH.

DID NOT CHANGE THE FORECAST BEYOND SUN. MODELS GENERALLY SHOW
ANOTHER LOW MOVING NEWD TOWARD THE AREA EARLY NEXT WEEK BUT DIFFER
ON EXACT TRACK. STILL...LOOKS LIKE A WET AND POTENTIALLY WINDY
PERIOD AS WELL. ALL IN ALL...LOOKS LIKE A RETURN TO MORE TYPICAL FALL
WEATHER FOR THE AREA.

.AJK WATCHES/WARNINGS/ADVISORIES...
PUBLIC...HIGH WIND WATCH FROM FRIDAY MORNING THROUGH FRIDAY AFTERNOON FOR
     AKZ027-028.
MARINE...SMALL CRAFT ADVISORY FOR PKZ033-035-036-041>043.

&&

PSS/RWT