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FXAK67 PAJK 221339
AFDAJK

SOUTHEAST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE JUNEAU AK
539 AM AKDT WED OCT 22 2014

.SHORT TERM...RATHER WINDY MORNING FOR SOME PARTS OF THE PANHANDLE
THIS MORNING. THE CENTRAL AND SOUTHERN PANHANDLE HAVE BEEN SEEING
GUSTS OF 30 TO 40 MPH FOR MOST OF THE NIGHT. THE CAUSE IS A STILL
RATHER POTENT LOW THAT HAS BEEN SPINNING THROUGH THE EASTERN GULF
OVERNIGHT. IT HAS SENT FIRST A FRONT OVER THE PANHANDLE YESTERDAY,
FOLLOWED BY THE SECOND WRAP OF THE SAME FRONT LAST NIGHT. THIS
MORNING IT IS A TROUGH THAT IS MOVING THROUGH THE PANHANDLE THAT
IS KEEPING THE WINDS HIGH. CURRENTLY CRAIG IS STILL GUSTING TO 40
MPH AND SITKA HAS GUSTED TO 39 MPH THIS MORNING AS WELL. HOWEVER
THE BIG WINNERS FOR WIND ARE CAPE SPENCER AND CAPE DECISION. THEY
HAVE BEEN GUSTING TO 55 KT AND 65 KT RESPECTIVELY ALL NIGHT.

FOR TODAY, THE TROUGH MOVING THROUGH THE PANHANDLE IS THE LAST
GASP FOR THE HIGH WINDS TODAY. WINDS HAVE ALREADY STARTED TO
DIMINISH IN THE SOUTHERN PANHANDLE AND WILL DIMINISH FROM SOUTH
TO NORTH THROUGH THE MORNING. STRONG WIND HEADLINES ARE STILL UP
FOR ZONES 23 AND 27 BUT SHOULD NOT EXTEND BEYOND MID MORNING. BY
MIDDAY MOST OF THE WINDS SHOULD HAVE DIED OFF AS THE MAIN LOW
MOVES OFF TO THE SW TAKING WHAT IS LEFT OF ITS VARIOUS FRONTAL
BANDS WITH IT. YAKUTAT MAY STILL SEE SOME BREEZY CONDITIONS THIS
AFTERNOON THOUGH AS THEY GET BRUSHED BY THE NORTHERN EDGE OF THE
TROUGH AS IT CONTINUES AROUND THE MAIN LOW.

AS FOR RAIN, 24 HOUR TOTALS HAVE NOT BEEN SPECTACULAR. HIGHEST
TOTALS ARE IN THE 3 TO 4 TENTHS OF AN INCH RANGE WITH HIGHEST
AMOUNTS RECORDED IN THE SOUTHERN HALF OF THE PANHANDLE. RIGHT NOW
THE RAIN IS CONVECTIVE IN NATURE WITH MOST OF THE SHOWERS
CONCENTRATED AROUND THE TROUGH THAT IS MOVING THROUGH THE
PANHANDLE. THESE SHOWERS WILL DIMINISH AND MOVE TO THE NW THROUGH
THE DAY WITH ONLY A QUARTER OF AN INCH OR LESS OF RAINFALL
EXPECTED.

TONIGHT`S FORECAST IS A BIT MORE COMPLICATED ESPECIALLY FOR THE
SOUTHERN PANHANDLE. THE REASON IS A WEAKER LOW THAT WILL BE
DEVELOPING SW OF HAIDA GWAII THIS AFTERNOON AS THE SURFACE
REFLECTION OF A 500 MB VORTICITY MAX AND WILL MOVE NORTH INTO THE
SE GULF TONIGHT. SHORT RANGE MODELS ARE HAVING TROUBLE ON
DETERMINING WHERE AND HOW FAST THE LOW WILL MOVE THROUGH THE SE
GULF TONIGHT MOSTLY BECAUSE THE FEATURE HASN`T ACTUALLY FORMED
YET. RUN TO RUN CONSISTENCY IS TERRIBLE FOR BEING A 24 HOUR
FORECAST AS THE LOW CENTER IS BOUNCING AROUND BY AS MUCH AS 100
MILES DEPENDING ON THE MODEL. SETTLED MORE ON THE ECMWF AS IT WAS
DISPLAYING LESS CONSISTENCY ISSUES THAN MANY OF THE OTHER MODELS.
IN ANY CASE THE SOUTHERN PANHANDLE IS IN FOR ANOTHER ROUND OF RAIN
TONIGHT AS THE LOW SPREADS A WEAK FRONTAL BOUNDARY NORTH. RAINFALL
AMOUNTS WILL ONLY BE IN THE QUARTER INCH OR LESS RANGE TONIGHT.
SOME WIND IS ALSO EXPECTED BUT WITH LOW LEVEL JET VALUES OF ONLY
35 KT I AM NOT EXPECTING ANY NEED FOR STRONG WIND HEADLINES
TONIGHT. STILL GUSTS TO 30 OR 35 MPH ARE NOT OUT OF THE QUESTION
FOR ZONES 27 AND 28 TONIGHT AS THIS WEAKER FRONTAL BAND MOVES
THROUGH. SMALL CRAFT ADVISORIES HAVE ALSO BEEN POSTED FOR THE SE
GULF AND CLARENCE STRAIT TONIGHT AS WELL.

FARTHER NORTH, EASTERLY AND NORTHERLY WINDS WILL HELP TO DRY OUT
THE AREA AND WILL CAUSE SEVERAL BREAKS TO FORM IN THE CLOUD COVER.
AS A RESULT OVERNIGHT LOWS MAY PLUMMET INTO THE 30S FOR MANY AREAS
ACROSS THE NORTHERN PANHANDLE. SOME PATCHY FOG MAY ALSO DEVELOP
OVERNIGHT AS THE LOW LEVEL ATMOSPHERE IS STILL MOIST FROM THE
RECENT RAINS. I AM NOT EXPECTING ANY DENSE FOG HOWEVER AS
NORTHERLY WINDS MAY PROVE TO BE TOO MUCH FOR FOG TO STICK AROUND
FOR ANY PERIOD OF TIME. SO HAVE ONLY INCLUDED PATCHY FOG IN THE
FORECAST FOR TONIGHT.

.LONG TERM...THE CLOSED UPPER LOW CURRENTLY OVER THE AK GULF WILL
WEAKEN TO AN OPEN WAVE TROUGH THROUGH THE END OF THE WEEK AS A
RIDGE OF HIGH PRESSURE MOVES IN FROM THE WEST. ANOTHER UPPER LEVEL
CLOSED LOW THAT DEVELOPED NEAR KAMCHATKA WILL MOVE OVER THE AK
INTERIOR FLATTENING THE RIDGE WITH A NEW TROUGH EXTENDING INTO THE
AK GULF ALONG FRONTAL BOUNDARY EXTENDING FROM THE MAIN LOW THROUGH
THE WEEKEND. BY THE START OF NEXT WEEK REMNANTS OF TROPICAL STORM
ANA WILL PROGRESS EASTWARD, BUT MAIN QUESTION IS IF THE SYSTEM
WILL BE PULLED INTO THE MID LATITUDE WESTERLY FLOW AND MOVE INTO
THE AK GULF OR MORE LIKELY STAY ALONG A SOUTHERLY TRACK NEARING
THE VANCOUVER COAST. AROUND MID WEEK THE ORIGINAL KAMCHATKA UPPER
LEVEL LOW LOW WILL DROP INTO THE AK GULF.

AT THE SURFACE THE SECONDARY LOW THAT DEVELOPED NEAR HAIDA GWAII
WILL PULL WESTWARD, MERGE WITH THE ORIGINAL LOW, THEN THE ENTIRE
CIRCULATION WILL WEAKEN AND MOVE TO THE SOUTHEAST. STILL SOME
LINGERING SHOWER BANDS FROM THIS SYSTEM MOVING OVER THE PANHANDLE
THURSDAY. A WEAK CIRCULATION FORMS IN THE NORTHERN AK GULF UNDER
THE FIRST UPPER LEVEL TROUGH MOVING IN FROM THE AK INTERIOR FRIDAY
INTO SATURDAY. WHILE THERE IS NOT MUCH SUPPORT FOR THIS SYSTEM
STILL HAVE 500 MB VORT MAX THAT WILL KEEP BANDS OF CHANCE POPS
OVER THE PANHANDLE. AS OPERATIONAL MODELS ARE NOT HANDLING THE
REMNANTS TROPICAL STORM ANA WELL IT IS DIFFICULT TO NAIL DOWN
TIMING AND POSITION OF THE NEXT MAIN FEATURES THAT MOST MODELS ARE
PREDICTING: A CLOSED SURFACE LOW FROM TROPICAL STORM ANA OVER THE
SOUTHERN GULF OR NORTH PACIFIC AND A CLOSED LOW FORMING IN THE
NORTHWESTERN GULF UNDER THE KAMCHATKA PARENT LOW. IF ANA STAYS
SOUTH THE NORTHWESTERN GULF LOW WILL MOVE IN FASTER, IF ANA MAKES
IT INTO THE AK GULF THE NORTHWESTERN GULF LOW WILL SLOW DOWN AND
EVENTUALLY MERGE WITH THE ANA REMNANTS. THUS KEEPING WITH AN
ENSEMBLE BLEND WITH CHANCE POPS THROUGH THE WEEK. WINDS OVER THE
GULF AND PANHANDLE WILL DIMINISH AS THE HAIDA GWAII LOW PULLS TO
THE WEST THEN PICK UP THROUGH THE WEEKEND AS THE NEXT SYSTEM
APPROACH. LOOKING AT LOWER TEMPS BY MID WEEK AS 850 MB TEMPS IN
THE -2 TO -4C RANGE MOVE DOWN FROM THE INTERIOR FROM THE TROUGHS
EXTENDING FROM THE KAMCHATKA LOW.

MODEL SPREAD BEGINS EARLY ON. THERE WAS A SHIFT AWAY FROM THE NAM
BY BOTH THE 00Z GFS AND ECMWF WHICH WERE NOW MORE IN LINE AT LEAST
ON THURSDAY. THE SHIFT IS MAINLY WITH THE LOCATION OF THE HAIDA
GWAII LOW WHICH THE NAM KEEPS FURTHER NORTH AND INTACT LONGER THAN
EITHER THE GFS OR ECMWF. LATER IN THE FORECAST THE ECMWF HAS BEEN
TRYING TO MOVE THE ANA REMNANTS INTO THE AK GULF WHILE THE GFS HAS
BEEN KEEPING THE SYSTEM OUT OF THE MID LATITUDE FLOW. WITH BOTH
OPERATIONAL MODELS SHOWING RUN TO RUN INCONSISTENCIES KEPT WITH
THE WPC ENSEMBLE SOLUTION. FORECAST CONFIDENCE IS BELOW AVERAGE
DUE TO CONTINUED MODEL DIFFICULTIES.

&&

.AJK WATCHES/WARNINGS/ADVISORIES...
PUBLIC...STRONG WIND UNTIL 10 AM AKDT THIS MORNING FOR AKZ023-027.
MARINE...GALE WARNING FOR PKZ022-033-036-041>043-051.
         SMALL CRAFT ADVISORY FOR PKZ011>013-021-031-032-034-035-052.
         SMALL CRAFT ADVISORY DUE TO SEAS FOR PKZ053.

&&

$$

EAL/PRB

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