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000
FXAK67 PAJK 222349
AFDAJK

SOUTHEAST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE JUNEAU AK
349 PM AKDT WED OCT 22 2014

.SHORT TERM...OVERALL THE PATTERN IS RUNNING AS EXPECTED. THE LOW
OVER THE GULF OF ALASKA WILL BE MOVING SOUTHWARD THROUGH THE NEXT
24 HOURS AND NEW LOW WILL BE MOVING NORTH AND START CURVING BACK
TO THE NORTHWEST BY HAIDA GWAII WED NIGHT. A RESIDUAL TROUGH OF
LOW PRESSURE WILL PERSIST OVER THE OUTER COASTAL WATERS BY
THURSDAY AFTERNOON.

THE OLD `PARENT` LOW HEADED SOUTH IS BEING AIDED BY A JET STREAK
(INCREASING TO THE 120-140KT RANGE) HELPING TO DIG THE UPPER LEVEL
THROUGH OVER THE GULF OF ALASKA SOUTHWARD AND IN RESPONSE, THE
DOWNSTREAM PORTION OF THE FLOW WILL BE SHIFTING NORTHWARD FROM THE
WASHINGTON/OREGON COAST BACK TO THE BRITISH COLUMBIA COAST.

A BAND OF STRATI-FORM RAIN IS MOVING OVER THE SOUTHERN PANHANDLE
AS THE SECOND LOW IS TRYING TO ROTATE ABOUT THE FIRST AND MOVE AWAY
FROM HAIDA GWAII. OTHERWISE, SHOWER ACTIVITY IS DIMINISHING OVER THE
NORTHERN PANHANDLE. WINDS AND SEAS ARE SUBSIDING ACROSS THE REGION
AS WELL. THE SMALL EXCEPTION TO THIS WILL BE A SLIGHT INCREASE IN
WINDS OVER THE LYNN CANAL AS THE GRADIENT TIGHTENS WITH THE LOW
APPROACH THE SOUTHERN THIS EVENING.

SOME ISOLATED LIGHTNING HAS BEEN MONITORED OVER THE WATERS AROUND
HAIDA GWAII EARLIER TODAY MOVING TO THE NORTH-NORTHEAST BUT DO
NOT THINK THAT WILL BE IMPACTING SOUTHEAST EAST ALASKA

.LONG TERM...LITTLE CHANGE IN THE EXTENDED RANGE FORECAST. THE
PAIR OF LOWS ROTATING AROUND EACH OTHER DURING THE SHORT RANGE
PERIOD LOOK LIKE THEY WILL COALESCE INTO A VERY WEAK CIRCULATION
SOUTHWEST OF HAIDA GWAII AND FADE AWAY TO THE SOUTHEAST THURSDAY
NIGHT. AS THIS HAPPENS, A WEAK LOW WILL FORM OVER THE FAR NORTH-
CENTRAL GULF AND A BROAD AREA OF WEAK LOW PRESSURE BETWEEN THE TWO
LOWS WILL DOMINATE THE EASTERN GULF THROUGH SATURDAY. THIS LOW
PRESSURE WILL TIGHTEN UP INTO A TROUGH SATURDAY NIGHT THROUGH
SUNDAY. SCATTERED SHOWERS FOR MOST PLACES THROUGH SATURDAY NIGHT,
THEN A CHANCE OF RAIN, PRIMARILY TO THE SOUTH AS LOW LEVEL
OFFSHORE FLOW AIDES IN DRYING OUT THE NORTHERN PANHANDLE.

TROPICAL STORM ANA CONTINUES TO CHURN NORTHWEST OF HAWAII. IR
SATELLITE IMAGERY NOT OVERLY IMPRESSIVE BUT TPW IMAGERY INDICATING
3 OR MORE INCHES OF PRECIPITABLE WATER. CURRENT FORECAST TRACK BY
THE JOINT TYPHOON WARNING CENTER KEEPS THE STORM SOUTH OF 50N
THROUGH MONDAY MORNING. CURRENT GFS IS EVEN FURTHER SOUTH, AS THAT
MODEL IS RUNNING THE SUB-TROPICAL JET IN A VERY ZONAL PATTERN WITH
A VERY CLEAR AND LARGE SEPARATION BETWEEN IT AND THE POLAR JET.
ECMWF AND GEM ARE STILL DIGGING AN UPPER TROUGH MUCH MORE
AGGRESSIVELY, CAUSING A PERTURBATION IN THE SUB-TROPICAL JET. THE
ECMWF THEN PICKS UP THE UPPER LEVEL CIRCULATION OF ANA AND CARRIES
IT FURTHER NORTH THAN GFS, BUT NOT NEARLY AS FAR, NOR AS STRONG, AS
YESTERDAY. IN THAT REGARD, THE MODELS ARE COMING INTO BETTER
ALIGNMENT, BUT THERE IS STILL A LONG WAY TO GO BEFORE THE
EXTENDED RANGE FORECAST CAN BE LABELED "HIGH CONFIDENCE". AS IT
IS, THE CURRENT LONG RANGE FORECAST IS CLOSELY ALIGNED WITH WPC
AND KEEPS THE CENTER OF CIRCULATION OVER HAIDA GWAII AND HECATE
STRAIT NEXT TUESDAY OR LATER. POTENTIAL EXISTS FOR HEAVY RAIN OVER
THE SOUTHERN PANHANDLE, BUT STILL TOO EARLY TO SAY WITH ANY
CERTAINTY AT ALL.

USED ECMWF AS THE FOUNDATION FOR UPDATES TO PRESSURE AND WIND
DIRECTIONS OVER THE GULF THROUGH SATURDAY NIGHT, BLENDED WITH GEM
AND NAM AT TIMES. WIND SPEEDS DURING THIS TIME FRAME DERIVED FROM
NAM. BLENDED CURRENT SREF TO EXISTING POP GRIDS - LITTLE CHANGE TO
THE FORECAST. OVERALL FORECAST CONFIDENCE IS AVERAGE.

&&

.AJK WATCHES/WARNINGS/ADVISORIES...
PUBLIC...NONE.
MARINE...SMALL CRAFT ADVISORY FOR PKZ012-033-036-041-042-051-052.
         SMALL CRAFT ADVISORY DUE TO SEAS FOR PKZ022-043.

&&

$$

BEZENEK/FRITSCH

VISIT US AT HTTP://WWW.WEATHER.GOV/JUNEAU










000
FXAK67 PAJK 222349
AFDAJK

SOUTHEAST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE JUNEAU AK
349 PM AKDT WED OCT 22 2014

.SHORT TERM...OVERALL THE PATTERN IS RUNNING AS EXPECTED. THE LOW
OVER THE GULF OF ALASKA WILL BE MOVING SOUTHWARD THROUGH THE NEXT
24 HOURS AND NEW LOW WILL BE MOVING NORTH AND START CURVING BACK
TO THE NORTHWEST BY HAIDA GWAII WED NIGHT. A RESIDUAL TROUGH OF
LOW PRESSURE WILL PERSIST OVER THE OUTER COASTAL WATERS BY
THURSDAY AFTERNOON.

THE OLD `PARENT` LOW HEADED SOUTH IS BEING AIDED BY A JET STREAK
(INCREASING TO THE 120-140KT RANGE) HELPING TO DIG THE UPPER LEVEL
THROUGH OVER THE GULF OF ALASKA SOUTHWARD AND IN RESPONSE, THE
DOWNSTREAM PORTION OF THE FLOW WILL BE SHIFTING NORTHWARD FROM THE
WASHINGTON/OREGON COAST BACK TO THE BRITISH COLUMBIA COAST.

A BAND OF STRATI-FORM RAIN IS MOVING OVER THE SOUTHERN PANHANDLE
AS THE SECOND LOW IS TRYING TO ROTATE ABOUT THE FIRST AND MOVE AWAY
FROM HAIDA GWAII. OTHERWISE, SHOWER ACTIVITY IS DIMINISHING OVER THE
NORTHERN PANHANDLE. WINDS AND SEAS ARE SUBSIDING ACROSS THE REGION
AS WELL. THE SMALL EXCEPTION TO THIS WILL BE A SLIGHT INCREASE IN
WINDS OVER THE LYNN CANAL AS THE GRADIENT TIGHTENS WITH THE LOW
APPROACH THE SOUTHERN THIS EVENING.

SOME ISOLATED LIGHTNING HAS BEEN MONITORED OVER THE WATERS AROUND
HAIDA GWAII EARLIER TODAY MOVING TO THE NORTH-NORTHEAST BUT DO
NOT THINK THAT WILL BE IMPACTING SOUTHEAST EAST ALASKA

.LONG TERM...LITTLE CHANGE IN THE EXTENDED RANGE FORECAST. THE
PAIR OF LOWS ROTATING AROUND EACH OTHER DURING THE SHORT RANGE
PERIOD LOOK LIKE THEY WILL COALESCE INTO A VERY WEAK CIRCULATION
SOUTHWEST OF HAIDA GWAII AND FADE AWAY TO THE SOUTHEAST THURSDAY
NIGHT. AS THIS HAPPENS, A WEAK LOW WILL FORM OVER THE FAR NORTH-
CENTRAL GULF AND A BROAD AREA OF WEAK LOW PRESSURE BETWEEN THE TWO
LOWS WILL DOMINATE THE EASTERN GULF THROUGH SATURDAY. THIS LOW
PRESSURE WILL TIGHTEN UP INTO A TROUGH SATURDAY NIGHT THROUGH
SUNDAY. SCATTERED SHOWERS FOR MOST PLACES THROUGH SATURDAY NIGHT,
THEN A CHANCE OF RAIN, PRIMARILY TO THE SOUTH AS LOW LEVEL
OFFSHORE FLOW AIDES IN DRYING OUT THE NORTHERN PANHANDLE.

TROPICAL STORM ANA CONTINUES TO CHURN NORTHWEST OF HAWAII. IR
SATELLITE IMAGERY NOT OVERLY IMPRESSIVE BUT TPW IMAGERY INDICATING
3 OR MORE INCHES OF PRECIPITABLE WATER. CURRENT FORECAST TRACK BY
THE JOINT TYPHOON WARNING CENTER KEEPS THE STORM SOUTH OF 50N
THROUGH MONDAY MORNING. CURRENT GFS IS EVEN FURTHER SOUTH, AS THAT
MODEL IS RUNNING THE SUB-TROPICAL JET IN A VERY ZONAL PATTERN WITH
A VERY CLEAR AND LARGE SEPARATION BETWEEN IT AND THE POLAR JET.
ECMWF AND GEM ARE STILL DIGGING AN UPPER TROUGH MUCH MORE
AGGRESSIVELY, CAUSING A PERTURBATION IN THE SUB-TROPICAL JET. THE
ECMWF THEN PICKS UP THE UPPER LEVEL CIRCULATION OF ANA AND CARRIES
IT FURTHER NORTH THAN GFS, BUT NOT NEARLY AS FAR, NOR AS STRONG, AS
YESTERDAY. IN THAT REGARD, THE MODELS ARE COMING INTO BETTER
ALIGNMENT, BUT THERE IS STILL A LONG WAY TO GO BEFORE THE
EXTENDED RANGE FORECAST CAN BE LABELED "HIGH CONFIDENCE". AS IT
IS, THE CURRENT LONG RANGE FORECAST IS CLOSELY ALIGNED WITH WPC
AND KEEPS THE CENTER OF CIRCULATION OVER HAIDA GWAII AND HECATE
STRAIT NEXT TUESDAY OR LATER. POTENTIAL EXISTS FOR HEAVY RAIN OVER
THE SOUTHERN PANHANDLE, BUT STILL TOO EARLY TO SAY WITH ANY
CERTAINTY AT ALL.

USED ECMWF AS THE FOUNDATION FOR UPDATES TO PRESSURE AND WIND
DIRECTIONS OVER THE GULF THROUGH SATURDAY NIGHT, BLENDED WITH GEM
AND NAM AT TIMES. WIND SPEEDS DURING THIS TIME FRAME DERIVED FROM
NAM. BLENDED CURRENT SREF TO EXISTING POP GRIDS - LITTLE CHANGE TO
THE FORECAST. OVERALL FORECAST CONFIDENCE IS AVERAGE.

&&

.AJK WATCHES/WARNINGS/ADVISORIES...
PUBLIC...NONE.
MARINE...SMALL CRAFT ADVISORY FOR PKZ012-033-036-041-042-051-052.
         SMALL CRAFT ADVISORY DUE TO SEAS FOR PKZ022-043.

&&

$$

BEZENEK/FRITSCH

VISIT US AT HTTP://WWW.WEATHER.GOV/JUNEAU










000
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

VISIT US AT HTTP://WWW.WEATHER.GOV/JUNEAU









000
FXAK67 PAJK 220002
AFDAJK

SOUTHEAST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE JUNEAU AK
402 PM AKDT TUE OCT 21 2014

.SHORT TERM...A VIGOROUS LOW OVER THE SOUTHEAST GULF OF ALASKA HAS
SPREAD ITS FRONTAL BAND NORTH ACROSS THE REGION AND IS NOW IN THE
VICINITY OF ICY STRAIT, CONTINUING NORTHWARD. NUMEROUS CONVECTIVE
CELLS BEHIND THE FRONT ARE ROTATING NORTHWARD. THERE WAS
SUFFICIENT INSTABILITY TO SUPPORT PLENTY OF MARINE THUNDERSTORM
ACTIVITY. LIGHTNING STRIKES DETECTED OVER THE EASTERN PACIFIC, HAIDA
GWAII, HECATE STRAIT AND SOUTH TO VANCOUVER ISLAND. THINK THAT
THIS ACTIVITY WILL BE SPREADING NORTH AND OUT OVER THE EASTERN
HALF OF THE GULF TONIGHT. THUNDER SHOULD BE LIMITED TO COASTAL
AREAS.

THE LOW WILL BE MOVING WEST TO THE WEST CENTRAL GULF OF ALASKA BY
WEDNESDAY MORNING. HOWEVER BEFORE IT PULLS AWAY THE SECOND WRAP
WILL GRAZE THE SOUTHERN COAST. AM EXPECTING GUSTY WINDS WITH
STRONG WIND HEADLINES FOR A LARGE PORTION OF SOUTHERN PANHANDLE
THROUGH THE EVENING HOURS.

WILL BEGIN TO SEE SOME IMPROVEMENT IN THE WEATHER AND WINDS AS THE
LOW RETREATS WEST. SEAS IN THE COASTAL WATERS IN THE UPPER TEENS
AND THAT WILL PERSIST THROUGH TONIGHT AND SLOWLY RECEDE AS WELL.

.LONG TERM...MODEL DIVERGENCE EARLY ON AS A WAVE DEVELOPS ALONG
THE PRE-EXISTING FRONTAL BOUNDARY ASSOCIATED WITH THE LOW DISCUSSED
ABOVE. THESE TWO FEATURES WILL ROTATE AROUND EACH OTHER, WITH THE
PARENT FILLING AND THE CHILD DEEPENING WHILE APPROACHING THE
SOUTHEAST OUTER COAST WEDNESDAY NIGHT. THE SECOND LOW WILL THEN
REMAIN SOMEWHAT ANCHORED OVER THE SOUTHEASTERN GULF THROUGH FRIDAY
NIGHT WHILE WEAKENING BEFORE EXITING THE FORECAST AREA TO THE
SOUTHEAST. TROUGHING WILL REMAIN OVER THE EASTERN GULF WITH
MULTIPLE EMBEDDED MID LEVEL CIRCULATIONS. THE VARIOUS LOWS AND
TROUGHS WILL CONTINUE TO PRODUCE SCATTERED SHOWERS AND/OR A CHANCE
OF RAIN THROUGH MUCH OF THE UPCOMING WEEK.

ATTENTION THEN TURNS TO TROPICAL STORM ANA. MORNING MODEL GUIDANCE
WAS VERY DISAPPOINTING WITH GFS KEEPING THE REMNANTS WELL TO THE
SOUTH AND TRACKING THEM INTO WESTERN CONUS WHILE ECMWF WAS
TRACKING AN EXTREMELY DEEP SYSTEM RIGHT INTO THE EASTERN GULF
EARLY NEXT WEEK. BASED ON THE CURRENT LOCATION OF THE STORM JUST
WEST OF HAWAII, IT DID NOT SEEM LIKELY THAT IT COULD GET DRIVEN
FAR ENOUGH NORTH IN THE PREVAILING WESTERLIES TO ENTER THE GULF.
SIMILAR THINKING BY WPC. 12Z ECMWF THEN CAME IN MUCH BETTER
AGREEMENT WITH THE MORNING GFS AND WHILE THE GFS IS STILL
EXHIBITING SOME RUN TO RUN VARIABILITY, THE AFTERNOON RUN
SUBSTANTIALLY IN AGREEMENT WITH THE MORNING RUN.

USED AN ENSEMBLE APPROACH WEDNESDAY NIGHT THROUGH SATURDAY NIGHT
FOR PRESSURE AND WIND, THEN TRANSITIONED TO WPC. USED GFS, GEM,
AND ECMWF FOR POP/QPF WEDNESDAY NIGHT THROUGH FRIDAY NIGHT,
BLENDING IN PROGRESSIVELY MORE OF THE EXISTING GRIDS. NO CHANGES
TO TEMPERATURES. OVERALL FORECAST CONFIDENCE IS AVERAGE.

&&

.AJK WATCHES/WARNINGS/ADVISORIES...
PUBLIC...STRONG WIND THROUGH LATE TONIGHT FOR AKZ026.
         STRONG WIND UNTIL 1 AM AKDT WEDNESDAY FOR AKZ027-028.
         STRONG WIND UNTIL 7 PM AKDT THIS EVENING FOR AKZ025.
         STRONG WIND THROUGH WEDNESDAY MORNING FOR AKZ023.
MARINE...GALE WARNING FOR PKZ022-033-035-036-041>043-051.
         SMALL CRAFT ADVISORY FOR PKZ011>013-021-031-032-034-052.

&&

$$

BEZENEK/FRITSCH

VISIT US AT HTTP://WWW.WEATHER.GOV/JUNEAU










000
FXAK67 PAJK 211352
AFDAJK

SOUTHEAST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE JUNEAU AK
552 AM AKDT TUE OCT 21 2014

.SHORT TERM...WINDY AND WET SHORT RANGE FORECAST IN THE WORKS AS A
GALE FORCE LOW CHURNS ITS WAY INTO THE SE GULF TODAY. RIGHT NOW
THE LOW IS STILL DOWN BY 50N 140W WITH ITS FRONT EXTENDING E
ACROSS THE SOUTHERN GULF TO NORTHERN HAIDA GWAII. THE FORWARD RAIN
BANDS AND SOME GUSTY WINDS HAVE ALREADY REACHED THE SOUTHERN
PANHANDLE THIS MORNING WITH GUSTS AS HIGH AS 35 MPH RECORDED AT
KETCHIKAN AND HYDABURG WITH SOME LIGHT RAIN. FARTHER NORTH THE
THERE ARE A FEW EFFECTS OF THE FRONT ALREADY BEING SEEN. THE FIRST IS
AN INCREASE IN HIGH LEVEL CLOUD COVER STOPPING TEMPERATURES FROM FALLING
SIGNIFICANTLY OVERNIGHT AND STALLING ANY FOG FORMATION THIS
MORNING. THE OTHER EFFECT IS CHANGING THE OVERALL PRESSURE
GRADIENT ACROSS THE PANHANDLE TO NORTH CAUSING WIND DIRECTION
SHIFTS FROM SOUTH TO NORTH IN SOME INNER CHANNEL AREAS.

FOR TODAY AND TONIGHT THE MAIN STORY WILL BE THE FRONT THE LOW IN
THE GULF SENDS OVER THE PANHANDLE FOLLOWED BY THE SECOND WRAP THAT
WILL PLOW IN BEHIND THE MAIN FRONT. THE MAIN FRONT WILL HEAD NORTH
OVER THE PANHANDLE TODAY SPREADING WIND AND RAIN AS IT GOES. THE
LOW LEVEL JET ACCOMPANYING THE FRONT IS ON THE ORDER OF 50 TO 55
KT. STRONG WIND HEADLINES ARE UP FOR ZONES 23, 26, 27 AND 28 AS A
RESULT WITH GUSTS TO UP TO 45 MPH EXPECTED. GALES ARE ALSO UP FOR
THE SOUTHERN GULF AND SOUTHERN INNER CHANNELS FOR THE SAME REASON.
HIGHEST WINDS WILL BE AROUND MIDDAY DURING FRONTAL PASSAGE WITH A
SECOND HIGHER MAXIMA THIS AFTERNOON AND EVENING AS THE SECOND
WRAP COMES ASHORE. WINDS FINALLY BEGIN DIMINISHING LATE TONIGHT AS
THE LOW BEGINS TO DRIFT WEST INTO THE CENTRAL GULF TAKING ITS
FRONTS WITH IT.

FARTHER NORTH THE NORTHERLY PRESSURE GRADIENT WILL BE THE PROBLEM
CHILD FOR WINDS TODAY. LYNN CANAL HAS JUST FLIPPED TO THE NORTH
ABOUT A HOUR AGO. THOSE WINDS WILL INCREASE TO 30 KT THIS
AFTERNOON AS NORTHERLY PRESSURE GRADIENTS INCREASE IN RESPONSE TO
THE FRONT COMING NORTH. THE OTHER AREA TO WATCH TODAY WILL BE
DOWNTOWN JUNEAU AND DOUGLAS FOR A MILD PRE-FRONTAL TAKU EVENT. NOT
ENTIRELY CONFIDENT ON THIS FEATURE AS CROSS BARRIER FLOW IS NOT
EXPECTED TO BE THAT STRONG (AROUND 30 TO 40 KT) AND THE CRITICAL
LEVEL IS NOT VERY WELL DEFENDED (THERE IS NO WIND DIRECTION SHIFT
ALOFT MORE OF A WEAKNESS IN THE GENERAL E FLOW ALOFT). STILL GUSTS
UP TO 40 MPH ARE POSSIBLE STARTING AROUND MIDDAY AND CONTINUING
INTO EARLY EVENING BEFORE SE SYNOPTIC FLOW CUTS IT OFF AND FLIPS
WIND DIRECTION TO MORE PARALLEL BARRIER FLOW. A STRONG WIND
HEADLINE HAS BEEN ISSUED FOR THE DOWNTOWN JUNEAU AND DOUGLAS AREA
FOR TODAY AS A RESULT.

AS FOR RAIN, NOT EXPECTING TOO MUCH PRECIP OUT OF THIS ONE.
LIMITING FACTORS ARE THAT MAIN MOISTURE PLUME IS AIMED AT THE AREA
SOUTH OF HAIDA GWAII AND THE NORTHERLY FLOW FOR THE NORTHERN PART
OF THE PANHANDLE. QPF AMOUNTS ARE IN THE HALF TO ONE INCH RANGE
MAINLY FOR THE SOUTHERN PANHANDLE AND OUTER COAST WITH LESSER
AMOUNTS FARTHER NORTH DUE TO THE NORTHERLY AND EASTERLY
DOWNSLOPING WINDS. THE MENTION OF ISOLATED THUNDERSTORMS HAS ALSO
BEEN INCLUDED FOR THE GULF WATERS AS A POCKET OF COOLER UPPER
LEVEL AIR AS WELL AS THE VORTICITY ASSOCIATED WITH THE LOW
DESTABILIZE THE SOUTHERN GULF TODAY AND TONIGHT.

SHORT RANGE MODELS WERE IN DECENT AGREEMENT BUT DID DISPLAY SOME
DIFFERENCES IN LOW POSITION BY LATE TONIGHT. GFS SEEMED TO BE A
BIT OF AN OUTLIER AS IT CARRIED THE LOW A LITTLE FURTHER WEST LATE
TONIGHT THEN MOST OTHER MODELS. PLUS IT GENERALLY UNDER DID THE
PRESSURE GRADIENT ACROSS THE PANHANDLE. GENERALLY FAVORED THE NAM
AND ECMWF FOR FORECAST GUIDANCE.

.LONG TERM...GALE FORCE LOW CURRENTLY MOVING INTO THE SOUTHERN AK
GULF WILL HAVE PULLED TO THE WEST NEARING KODIAK ISLAND BY
WEDNESDAY. THE ASSOCIATED FRONT CROSSES MOVED THE NORTHERN
PANHANDLE MOVING TOWARDS PRINCE WILLIAM SOUND. THE LOW WILL DROP
SOUTHEASTWARD AGAIN WITH A SECONDARY CIRCULATION ROTATING TO THE
SOUTH OF THE MAIN LOW WILL BEGIN TO DEVELOP OFF THE WEST COAST OF
HAIDA GWAII THURSDAY. CURRENT MODEL RUNS INDICATE THE ENTIRE
SYSTEM WILL BE DRIVEN SOUTHWARD BY FRIDAY AS UPPER LEVEL RIDGE
ADVANCES INTO THE WESTERN GULF. A CLOSED UPPER LOW ORIGINATING
OFF KAMCHATKA WILL MOVE OVER THE RIDGE WITH A TROUGH EXTENDING
INTO THE GULF AND FLATTENING THE RIDGE OVER THE WEEKEND THEN
FORMED A CLOSED CIRCULATION OVER THE AK GULF BY THE START OF NEXT
WEEK. MEANWHILE THE REMNANTS OF TROPICAL STORM ANA WILL MOVE
NORTHWARD AND AT THIS TIME MODELS ARE HAVING DIFFICULTY
DETERMINING IF THIS FEATURE WILL BE INCORPORATED INTO THE WESTERLY
MID LATITUDE FLOW AND REACH THE AK GULF OR REMAIN SOUTH OF THE
MAIN FLOW AND MISS OUR AREA. THUS THERE HAS BEEN SIGNIFICANT RUN
TO RUN INCONSISTENCY AND MODEL SPREAD AND THUS LOW FORECAST
CONFIDENCE.

WHAT IS EXPECTED IS PRECIP AND WINDS TO DIMINISH AS THE FRONT MOVES
OVER THE NORTHERN PANHANDLE AND THE PRESSURE GRADIENT WEAKENS. THE
POSITION AND STRENGTH OF THE SECONDARY CIRCULATION OFF HAIDA GWAII
IS UNCERTAIN WITH THE NAM/GFS KEEPING THIS LOW SOUTH OFT THE AK
GULF RESULTING IN DRIER WEATHER WHILE THE ECMWF/GEM MOVE IT OFF
THE SOUTHERN PANHANDLE COAST AND THUS MOVE IN MORE PRECIP TO THE
REGION. AT THIS TIME WHILE THE NAM DID INITIALIZE WELL IT ALSO IS
CURRENTLY IN LINE WITH THE ECMWF AND THUS THE SPLIT BETWEEN THESE
MODELS TOWARD THE END OF THE WEEK DOES NOT WARRANT MUCH CONFIDENCE
IN EITHER SOLUTION. THERE IS ALSO LARGE MODEL DIFFERENCE WITH THE
TIMING OF THE UPPER LEVEL TROUGH MOVING INTO THE N AK GULF BY THE
WEEKEND AND THUS DIFFERENCES IN A POTENTIAL SURFACE CIRCULATION
FORMING IN THE NORTHERN GULF AND PRODUCING PRECIP OVER THE
PANHANDLE. AND AS MENTIONED ABOVE ANA REMNANTS MAY HI THE AK GULF
MONDAY AS INDICATED BY THE ECMWF OR KEEP TO THE SOUTH PER THE GFS.
HENCE KEEPING WITH AN ENSEMBLE SOLUTION OF MOSTLY CLOUDY WITH
CHANCE OF RAIN.

INITIALLY BLENDED IN SOME 00Z NAM WITH INHERITED GRIDS SINCE THE NAM
INITIALIZED WELL AND SEEMED TO BE IN LINE WITH AT LEAST ONE MODEL
THROUGH MID RANGE. KEEP WITH WPC ENSEMBLE SOLUTION FOR THE REST OF THE
EXTENDED RANGE FORECAST. FORECAST CONFIDENCE IS BELOW AVERAGE
INITIALLY AND THE DROPS BY THE WEEKEND.

&&

.AJK WATCHES/WARNINGS/ADVISORIES...
PUBLIC...STRONG WIND FROM 1 PM AKDT THIS AFTERNOON THROUGH LATE TONIGHT
     FOR AKZ026.
         STRONG WIND THROUGH LATE TONIGHT FOR AKZ027.
         STRONG WIND FROM 10 AM AKDT THIS MORNING THROUGH THIS EVENING
     FOR AKZ025.
         STRONG WIND FROM 1 PM AKDT THIS AFTERNOON THROUGH WEDNESDAY
     MORNING FOR AKZ023.
         STRONG WIND THROUGH LATE TONIGHT FOR AKZ028.
MARINE...GALE WARNING FOR PKZ022-033-035-036-041>043-051.
         SMALL CRAFT ADVISORY FOR PKZ011>013-021-031-032-034-052.

&&

$$

EAL/PRB

VISIT US AT HTTP://WWW.WEATHER.GOV/JUNEAU








000
FXAK67 PAJK 202337
AFDAJK

SOUTHEAST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE JUNEAU AK
337 PM AKDT MON OCT 20 2014

.SHORT TERM...WIDESPREAD SHOWERS HAVE FALLEN OVER THE
PANHANDLE AS A TROUGH HAS PUSHED THROUGH THE NORTHERN/CENTRAL
PANHANDLE TODAY. LIGHTNING AND THUNDERSTORMS HAVE REMAINED SOUTH
OF US IN HECATE STRAIT...BUT A RISK LATE THIS AFTERNOON CONTINUES
ACROSS THE OUTSIDE WATERS AND THE SOUTHERN PANHANDLE. BUILDING
OFFSHORE FLOW WITH SOME STABILIZING CONDITIONS ALOFT SHOULD LIMIT
THIS RISK TO LATE MONDAY AFTERNOON. AS THIS TROUGH HAS MOVED
IN...PRESSURE ROSE ACROSS THE PANHANDLE AND THUS ALLOWED LYNN
CANAL TO RISE TO 25 KT THIS AFTERNOON. HOWEVER, AS THE ISOBARS
RE-TILT NORTHWESTWARD IN RESPONSE TO THE DEVELOPING SYSTEM OVER THE
CENTRAL OUTER GULF, WINDS WILL LARGELY FLIP NORTH AND BEGIN
STRENGTHENING INTO TUESDAY.

TUESDAY THIS GALE FORCE LOW IN THE OUTER GULF WILL CURVE TO THE
NORTHEAST TO LIE SQUARELY IN THE SOUTHEAST GULF BY TUESDAY. GALES
WILL SPREAD AS FAR NORTH AS 43 AND WILL PENETRATE THE INSIDE IN
BOTH CLARENCE STRAIT BEGINNING TUESDAY MORNING AND SOUTHERN
CHATHAM BEGINNING TUESDAY AFTERNOON. PRINCE OF WALES ISLAND WILL
BEGIN EXPERIENCING STRONG WIND GUSTS TO 40 MPH EARLY TUESDAY
MORNING AND REMAINING STRONG THROUGH THE REST OF THE DAY.
KETCHIKAN AND METLAKATLA WILL SEE WINDS RISE A FEW HOURS LATER
TUESDAY.

THE LOBE OF VORTICITY SUPPORTING THE LOW WILL USHER A WAVE OF
SORTS THROUGH THE PANHANDLE TOMORROW AND SHOULD HELP INDUCE SOME
MOUNTAIN WAVE GUSTINESS OVER DOWNTOWN JUNEAU BEGINNING LATE
TUESDAY MORNING. HIGH RESOLUTION MODELS INDICATE SUSTAINED WIND
SPEEDS OF CLOSE TO 30 MPH...ALSO RAISED THE JUNEAU DOWNTOWN HIGH
TEMPERATURE TO CAPTURE DOWNSLOPING COMPRESSIONAL TEMPERATURE
RISES. CERTAIN RAIN SHOULD HOLD SOUTH OF ANGOON/SITKA TUESDAY
AFTERNOON...BUT STILL DECORATE THE NORTH WITH AT LEAST A CHANCE.
YAKUTAT SHOULD REMAIN DRY AFTER SHOWERS DIMINISH TONIGHT. ADDED
SOME SNOW MIXING IN TO YAKUTAT LATE, BUT MORE LIKELY TEMPERATURES
WILL NOT COOL ENOUGH FOR SNOW UNTIL AFTER SHOWERS HAVE ENDED.

SOME THOUGHT GIVEN TO PRECIPITATION CHARACTER. CONVECTION
PARAMETERS OVER THE GULF UNSTABLE ENOUGH TO INCLUDE SLIGHT CHANCE
OF THUNDERSTORMS EVEN THOUGH TEXTBOOK PARADIGMS URGE STRATIFORM
AHEAD OF THE SYSTEM. IN ACTUALITY THE ATMOSPHERE WILL HAVE A
COMPLEX HYBRID STABILITY. WHERE THUNDERSTORMS FORECAST...WENT
CONVECTIVE...WHERE NOT WENT STRATIFORM...GENERALLY OVER THE LAND.

SOME PATCHY FOG MAY FORM TONIGHT AS SHOWERS DIMINISH AND CLOUDS
BEGIN SHOWING BREAKS, BUT FELT WINDS MAY BE TOO STRONG OVER THE
INSIDE WATERS ITSELF SO CONFINED IT TO LAND AREAS OVER THE
NORTHERN AREAS.

USED GUIDANCE FROM NAM EARLY...BUT AS IT BEGAN TO BECOME THE ODD
MODEL OUT WITH THE LOW IN THE GULF...WAS INCLINED TO FOLLOW A
GEM/ECMWF CONSENSUS. FORECAST CONFIDENCE GOOD.

.LONG TERM...THE MAIN LOW FOR THE INCOMING SYSTEM LOOPS AROUND THE
GULF OF ALASKA THROUGH MID WEEK AND DIVING SOUTH-SOUTHEAST TO OUT
OF THE GULF OF ALASKA. MODELS HINT AT SMALL WAVE MOVING UPTO
TOWARDS THE PRINCE OF WALES ISLAND AREA THU HELPING TO PULL THE
OLD LOW SOUTHWARD. EXPECT AN INVERTED TROUGH OF LOW PRESSURE
ACROSS THE EASTERN GULF ALONG THE PANHANDLE FRIDAY TO SATURDAY
THAT WILL DEFLECT AN RIDGE AHEAD OF THE NEXT WEATHER SYSTEM SOUTH
OF THE GULF OF ALASKA. THIS NEXT SYSTEM WILL BE DEVELOPING IN THE
NORTH PACIFIC AND WILL HEAD EAST TOWARD VANCOUVER ISLAND FOR NEXT
WEEKEND. IT IS LAST LOW THAT LOOKS TO HAVE ABSORBED THE REMAINS OF
ANA CURRENTLY PASSING BY HAWAII.

BELIEVE THAT THE GALE FORCE WINDS AND ISOLATE THUNDER FROM TUESDAY
WILL CONTINUE INTO TUESDAY NIGHT BEFORE SUBSIDING AND TAPERING
OFF. THINK MOST OF THE PRECIPITATION WILL BE ACTING SIMILAR TO
SHOWERS THUS WAS MY REASONS FOR MAKING THE PRECIPITATION THAT TYPE.
THE LOW WHEN IT DOES FINALLY START TO PULL OF THE OF THE GULF WILL
BE PULLING SOME COOLER AIR FROM THE INTERIOR OUT OVER THE GULF
MAINTAINING A GOOD SHOWER PATTERN THROUGH MUCH OF THE WEEK.
CONFIDENCE IS GENERALLY GOOD TO THURSDAY OR FRIDAY AND LOWER NEXT
WEEK...AS THE MODELS HAVE SOME CONSISTENCY ISSUES HANDLING THE ANA
SYSTEM.


&&

.AJK WATCHES/WARNINGS/ADVISORIES...
PUBLIC...STRONG WIND FROM LATE TONIGHT THROUGH TUESDAY EVENING FOR AKZ027.
         STRONG WIND FROM TUESDAY MORNING THROUGH TUESDAY EVENING FOR
     AKZ025.
         STRONG WIND FROM TUESDAY AFTERNOON THROUGH TUESDAY EVENING FOR
     AKZ023.
         STRONG WIND FROM TUESDAY MORNING THROUGH TUESDAY EVENING FOR
     AKZ028.
MARINE...GALE WARNING FOR PKZ022-033-036-041>043.
         SMALL CRAFT ADVISORY FOR PKZ011>013-021-031-032-034-035-051.
         SMALL CRAFT ADVISORY DUE TO SEAS FOR PKZ052.

&&

$$

JWA/BEZENEK

VISIT US AT HTTP://WWW.WEATHER.GOV/JUNEAU








000
FXAK67 PAJK 201345
AFDAJK

SOUTHEAST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE JUNEAU AK
545 AM AKDT MON OCT 20 2014

.SHORT TERM...CONSTANTLY SHIFTING WINDS AND SHOWERS HAVE BEEN THE
RULE OF THE NIGHT ACROSS THE PANHANDLE. THE COMPACT LOW THAT
BROUGHT THE BRIEF BURST OF WIND LAST EVENING HAS MOVED INTO THE
YUKON THIS MORNING. THE SOUTHERLY WINDS THAT IT KICKED UP ARE
GRADUALLY DIMINISHING AND STARTING TO SWITCH BACK TO A NORTHERLY
DIRECTION AS THE TROUGH JUST OFFSHORE BEGINS TO MOVE EAST.
CURRENTLY THE HIGHEST WINDS ARE IN THE SOUTHERN PANHANDLE WHERE A
850 MB LOW LEVEL JET OF AROUND 35 KT IS CREATING SOME GUSTY WINDS
THIS MORNING. AS FOR THE SHOWERS, THEY ARE WIDE SPREAD ACCORDING
TO THE RADAR WITH SOME HEAVIER SHOWERS AND ISOLATED THUNDERSTORMS
INTERMIXED FOR THE SOUTHERN PANHANDLE AND GULF.

THE MAIN THEME OF THE SHORT RANGE IS THAT WE ARE IN THE
TRANSITION ZONE BETWEEN SYSTEMS. THE TROUGH THAT IS CURRENTLY
JUST OFF THE OUTER COAST WILL MOVE NE OVER THE PANHANDLE TODAY.
EVENTUALLY ALLOWING THE SHOWERS TO DIMINISH ACROSS THE PANHANDLE
TONIGHT. THE THREAT OF SOME ISOLATED THUNDERSTORMS GRADUALLY
TAPERS OFF TODAY AS WELL AS THE TROUGH TAKES THE WEDGE OF COOLER
AIR AND VORTICITY ALOFT INTO CANADA ALLOWING THE ATMOSPHERE TO
STABILIZE. OVERALL RAINFALL SHOULD BE IN THE QUARTER TO HALF INCH
NEIGHBORHOOD THROUGH TONIGHT BUT SOME LOCALIZED AREAS OF HIGHER
AMOUNTS ARE POSSIBLE FROM HEAVIER SHOWERS.

WINDS WILL BE THE COMPLICATING FACTOR MOSTLY DUE TO THE FACT THAT
THEY WILL BE SWITCHING DIRECTION QUITE A FEW TIMES PARTICULARLY IN
THE NORTHERN PANHANDLE. MOST WINDS THIS MORNING HAVE STARTED OUT
SOUTH BUT LYNN CANAL WILL HAVE A BRIEF PERIOD WHERE THE WINDS TURN
NORTH THIS MORNING DUE TO THE GULF TROUGH MOVING CLOSER. THEY WILL
THEN SWITCH TO THE SOUTH THIS AFTERNOON AS THE TROUGH MOVES
THROUGH AND EVEN INCREASE TO SMALL CRAFT FOR NORTHERN LYNN AS THE
TROUGH REFORMS IN THE SOUTHERN YUKON. THESE SOUTHERLY WINDS WILL
THEN DECREASE THIS EVENING BEFORE SWITCHING AGAIN TO THE NORTH AS
THE NEXT MAJOR GULF LOW BEGINS TO INFLUENCE THE PANHANDLE. FARTHER
SOUTH THE GUSTY WINDS IN THE SOUTHERN PANHANDLE THIS MORNING WILL
GRADUALLY DIMINISH TODAY AS THE LOW LEVEL JET WEAKENS. WINDS WILL
STAY OUT OF THE SOUTHEAST THOUGH AND WILL INCREASE AGAIN LATER
TONIGHT. AS FOR EAST/WEST CHANNELS, THEY START OUT MOSTLY EAST
BUT WILL SWITCH TO THE SW THIS AFTERNOON IN THE WAKE OF THE
TROUGH. THE SOUTHWEST WINDS WILL PERSIST THROUGH THE EVENING
BEFORE SWITCHING AGAIN IN THE LATE EVENING BACK TO EAST DUE ONCE
AGAIN TO THE NEXT LOW`S INFLUENCE.

SPEAKING OF THE NEXT LOW, IT WILL JUST BE ENTERING THE SOUTHERN
GULF BY LATE TONIGHT AFTER STRENGTHENING TO 972 MB DUE TO SITTING
UNDER THE LEFT EXIT REGION OF A 95 KT JET STREAK. WE CATCH IT JUST
AS IT STARTS TO SEPARATE FROM THAT JET STREAK AND TURN NORTH. ITS
ASSOCIATED FRONT WILL BEGIN TO INFLUENCE THE WEATHER OVER THE
PANHANDLE LATE TONIGHT. IN ADDITION TO THE WIND DIRECTION SHIFTS
FARTHER NORTH, THE FRONT WILL BE INCREASING WIND SPEED ACROSS THE
SOUTHERN PANHANDLE LATE TONIGHT AS IT DIRECTS A 50 TO 55 KT LOW
LEVEL JET INTO THAT AREA. GALE WARNINGS HAVE BEEN ISSUED FOR THE
SE GULF AND CLARENCE STRAIT AS A RESULT AND STRONG WIND HEADLINES
HAVE ALSO BEEN HOISTED FOR ZONES 27 AND 28 WITH GUSTS EXPECTED TO
REACH 45 MPH. RAIN WILL ALSO BE STARTING UP AGAIN LATE TONIGHT.
THE MAIN FRONTAL RAINBANDS SHOULD REACH THE SOUTHERN PANHANDLE
AFTER MIDNIGHT AND MAY NOT GET ANY FARTHER NORTH THAN SOUTHERN
BARANOF ISLAND BY THE END OF THE SHORT RANGE PERIOD LATE TONIGHT.

SHORT RANGE MODELS WERE IN DECENT AGREEMENT BUT THERE WERE SOME
DIFFERENCES IN DETAILS. DISCARDED THE GFS AS IT WAS TOO WEAK WITH
THE LOW THAT WENT THROUGH LAST NIGHT. LIKED THE NAM AS IT DID THE
BEST REPRESENTING THE PRESSURE GRADIENT CHANGES OVER THE NEXT 24
HOURS. GEM AND ECMWF WERE IN SECOND PLACE AS THEY HAD THE SAME
IDEA BUT WERE NOT QUITE AS STRONG.

.LONG TERM...THE UPPER LOW THAT MOVED INTO THE SOUTHERN AK GULF
WILL ROTATE NORTHWARD ON TUESDAY, RETROGRADE TO THE WEST WEDNESDAY
THEN EXPECTED TO PULL SOUTHWARD TOWARD THE VANCOUVER COAST THURSDAY
INTO FRIDAY. THE ASSOCIATED GALE FORCE SURFACE LOW WILL FOLLOW A
SIMILAR TRACK WITH FRONTAL BANDS MOVING OVER THE REGION TUESDAY
AND TUESDAY NIGHT THEN PULLING TO THE WEST WEDNESDAY. BY THE
WEEKEND A HIGH PRESSURE RIDGE BUILDS OVER THE WESTERN GULF MOVING
EASTWARD, HOWEVER AN UPPER LOW DROPS FROM THE INTERIOR INTO THE
NORTHERN GULF AND EVENTUALLY THE PANHANDLE. MODELS ARE SHOWING
LARGE SPREAD AND RUN TO RUN INCONSISTENCY DUE TO TROPICAL SYSTEM
ANA BEING INCORPORATED INTO THE MID LATITUDE FLOW AND MERGING WITH
A WAVE THAT DEVELOPED OVER KAMCHATKA.

STRONG WINDS OVER THE SOUTHERN PANHANDLE WILL CONTINUE INTO
TUESDAY NIGHT WAS THE FIRST AND SECOND WRAPS MOVE OVER THE REGION.
WINDS WILL INCREASE OVER THE CENTRAL AND COASTAL PANHANDLE AS THE
LOW MOVES NORTHWARD THROUGH THE DAY WITH 850 MB WINDS IN THE 45 TO
55 MPH. EASTERLY OUTFLOW AND GAP WINDS WILL PICK UP THROUGH
TUESDAY WITH GUST IN THE 40 TO 5O KT RANGE DUE TO THE TIGHTENING
GRADIENT BETWEEN THE GULF LOW AND HIGH PRESSURE OVER WESTERN
CANADA. NEW MODEL RUNS HAD THE LOW BIT DEEPER SO WINDS WERE NUDGED
UP FROM PREVIOUS FORECAST. AS OF NOW WINDS SHOW A QUICK DROP OFF
LATE WEDNESDAY INTO THURSDAY AND BEGIN TO SHIFT FROM NORTH TO
SOUTH BY THE WEEKEND. THE BANDED NATURE OF LOW MEANS PRECIPITATION
MAY NOT BE A STEADY THROUGH TUESDAY AND HAVE HIGHER UNCERTAINTY
ON PRECIPITATION TIMING ON WEDNESDAY WHEN MODEL SPREAD ON THE LOW
POSITION STARTS TO INCREASE. NOT MUCH CHANGE IN TEMPS THROUGH THE
WEEK AS 850 MB TEMPS REMAIN BETWEEN 0 AND 2 C. LATER IN THE WEEK AS
THE UPPER LOW DROPS DOWN FORM THE INTERIOR COLDER AIR MASS MOVES
IN SO EXPECTING TEMPS TO DROP FOR THE NORTHERN AND NORTH COASTAL
PANHANDLE WITH POSSIBLE SNOW FALL FOR THESE AREAS.

GOOD INITIALIZATION WITH THE NAM/GEM FOR PRESSURE. THE ECMWF / GFS
ARE NOT FAR OFF BUT DO SHOW DIFFERENCES IN POSITION AND STRENGTH
OF THE LOW. BY WEDNESDAY MODEL SPREAD INCREASES WITH ECMWF
BECOMING THE FIRST OUTLIER. WENT WITH AN ENSEMBLE APPROACH FOR THE
REST OF THE EXTENDED RANGE USING A BLEND OF WPC. FORECAST
CONFIDENCE IS ONLY AVERAGE INITIALLY DUE TO UNCERTAINTY IN TIMING
THE BANDS ROTATING AROUND THE LOW. CONFIDENCE DOES NOT IMPROVE
THROUGH THE WEEK DUE TO THE LARGE MODEL SPREAD.

&&

.AJK WATCHES/WARNINGS/ADVISORIES...
PUBLIC...STRONG WIND FROM LATE TONIGHT THROUGH TUESDAY MORNING FOR AKZ027-
     028.
MARINE...GALE WARNING FOR PKZ036-041-042.
         SMALL CRAFT ADVISORY FOR PKZ012-021-022-031>035-043-051-052.
         SMALL CRAFT ADVISORY DUE TO SEAS FOR PKZ053.

&&

$$

EAL/PRB

VISIT US AT HTTP://WWW.WEATHER.GOV/JUNEAU








000
FXAK67 PAJK 201345
AFDAJK

SOUTHEAST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE JUNEAU AK
545 AM AKDT MON OCT 20 2014

.SHORT TERM...CONSTANTLY SHIFTING WINDS AND SHOWERS HAVE BEEN THE
RULE OF THE NIGHT ACROSS THE PANHANDLE. THE COMPACT LOW THAT
BROUGHT THE BRIEF BURST OF WIND LAST EVENING HAS MOVED INTO THE
YUKON THIS MORNING. THE SOUTHERLY WINDS THAT IT KICKED UP ARE
GRADUALLY DIMINISHING AND STARTING TO SWITCH BACK TO A NORTHERLY
DIRECTION AS THE TROUGH JUST OFFSHORE BEGINS TO MOVE EAST.
CURRENTLY THE HIGHEST WINDS ARE IN THE SOUTHERN PANHANDLE WHERE A
850 MB LOW LEVEL JET OF AROUND 35 KT IS CREATING SOME GUSTY WINDS
THIS MORNING. AS FOR THE SHOWERS, THEY ARE WIDE SPREAD ACCORDING
TO THE RADAR WITH SOME HEAVIER SHOWERS AND ISOLATED THUNDERSTORMS
INTERMIXED FOR THE SOUTHERN PANHANDLE AND GULF.

THE MAIN THEME OF THE SHORT RANGE IS THAT WE ARE IN THE
TRANSITION ZONE BETWEEN SYSTEMS. THE TROUGH THAT IS CURRENTLY
JUST OFF THE OUTER COAST WILL MOVE NE OVER THE PANHANDLE TODAY.
EVENTUALLY ALLOWING THE SHOWERS TO DIMINISH ACROSS THE PANHANDLE
TONIGHT. THE THREAT OF SOME ISOLATED THUNDERSTORMS GRADUALLY
TAPERS OFF TODAY AS WELL AS THE TROUGH TAKES THE WEDGE OF COOLER
AIR AND VORTICITY ALOFT INTO CANADA ALLOWING THE ATMOSPHERE TO
STABILIZE. OVERALL RAINFALL SHOULD BE IN THE QUARTER TO HALF INCH
NEIGHBORHOOD THROUGH TONIGHT BUT SOME LOCALIZED AREAS OF HIGHER
AMOUNTS ARE POSSIBLE FROM HEAVIER SHOWERS.

WINDS WILL BE THE COMPLICATING FACTOR MOSTLY DUE TO THE FACT THAT
THEY WILL BE SWITCHING DIRECTION QUITE A FEW TIMES PARTICULARLY IN
THE NORTHERN PANHANDLE. MOST WINDS THIS MORNING HAVE STARTED OUT
SOUTH BUT LYNN CANAL WILL HAVE A BRIEF PERIOD WHERE THE WINDS TURN
NORTH THIS MORNING DUE TO THE GULF TROUGH MOVING CLOSER. THEY WILL
THEN SWITCH TO THE SOUTH THIS AFTERNOON AS THE TROUGH MOVES
THROUGH AND EVEN INCREASE TO SMALL CRAFT FOR NORTHERN LYNN AS THE
TROUGH REFORMS IN THE SOUTHERN YUKON. THESE SOUTHERLY WINDS WILL
THEN DECREASE THIS EVENING BEFORE SWITCHING AGAIN TO THE NORTH AS
THE NEXT MAJOR GULF LOW BEGINS TO INFLUENCE THE PANHANDLE. FARTHER
SOUTH THE GUSTY WINDS IN THE SOUTHERN PANHANDLE THIS MORNING WILL
GRADUALLY DIMINISH TODAY AS THE LOW LEVEL JET WEAKENS. WINDS WILL
STAY OUT OF THE SOUTHEAST THOUGH AND WILL INCREASE AGAIN LATER
TONIGHT. AS FOR EAST/WEST CHANNELS, THEY START OUT MOSTLY EAST
BUT WILL SWITCH TO THE SW THIS AFTERNOON IN THE WAKE OF THE
TROUGH. THE SOUTHWEST WINDS WILL PERSIST THROUGH THE EVENING
BEFORE SWITCHING AGAIN IN THE LATE EVENING BACK TO EAST DUE ONCE
AGAIN TO THE NEXT LOW`S INFLUENCE.

SPEAKING OF THE NEXT LOW, IT WILL JUST BE ENTERING THE SOUTHERN
GULF BY LATE TONIGHT AFTER STRENGTHENING TO 972 MB DUE TO SITTING
UNDER THE LEFT EXIT REGION OF A 95 KT JET STREAK. WE CATCH IT JUST
AS IT STARTS TO SEPARATE FROM THAT JET STREAK AND TURN NORTH. ITS
ASSOCIATED FRONT WILL BEGIN TO INFLUENCE THE WEATHER OVER THE
PANHANDLE LATE TONIGHT. IN ADDITION TO THE WIND DIRECTION SHIFTS
FARTHER NORTH, THE FRONT WILL BE INCREASING WIND SPEED ACROSS THE
SOUTHERN PANHANDLE LATE TONIGHT AS IT DIRECTS A 50 TO 55 KT LOW
LEVEL JET INTO THAT AREA. GALE WARNINGS HAVE BEEN ISSUED FOR THE
SE GULF AND CLARENCE STRAIT AS A RESULT AND STRONG WIND HEADLINES
HAVE ALSO BEEN HOISTED FOR ZONES 27 AND 28 WITH GUSTS EXPECTED TO
REACH 45 MPH. RAIN WILL ALSO BE STARTING UP AGAIN LATE TONIGHT.
THE MAIN FRONTAL RAINBANDS SHOULD REACH THE SOUTHERN PANHANDLE
AFTER MIDNIGHT AND MAY NOT GET ANY FARTHER NORTH THAN SOUTHERN
BARANOF ISLAND BY THE END OF THE SHORT RANGE PERIOD LATE TONIGHT.

SHORT RANGE MODELS WERE IN DECENT AGREEMENT BUT THERE WERE SOME
DIFFERENCES IN DETAILS. DISCARDED THE GFS AS IT WAS TOO WEAK WITH
THE LOW THAT WENT THROUGH LAST NIGHT. LIKED THE NAM AS IT DID THE
BEST REPRESENTING THE PRESSURE GRADIENT CHANGES OVER THE NEXT 24
HOURS. GEM AND ECMWF WERE IN SECOND PLACE AS THEY HAD THE SAME
IDEA BUT WERE NOT QUITE AS STRONG.

.LONG TERM...THE UPPER LOW THAT MOVED INTO THE SOUTHERN AK GULF
WILL ROTATE NORTHWARD ON TUESDAY, RETROGRADE TO THE WEST WEDNESDAY
THEN EXPECTED TO PULL SOUTHWARD TOWARD THE VANCOUVER COAST THURSDAY
INTO FRIDAY. THE ASSOCIATED GALE FORCE SURFACE LOW WILL FOLLOW A
SIMILAR TRACK WITH FRONTAL BANDS MOVING OVER THE REGION TUESDAY
AND TUESDAY NIGHT THEN PULLING TO THE WEST WEDNESDAY. BY THE
WEEKEND A HIGH PRESSURE RIDGE BUILDS OVER THE WESTERN GULF MOVING
EASTWARD, HOWEVER AN UPPER LOW DROPS FROM THE INTERIOR INTO THE
NORTHERN GULF AND EVENTUALLY THE PANHANDLE. MODELS ARE SHOWING
LARGE SPREAD AND RUN TO RUN INCONSISTENCY DUE TO TROPICAL SYSTEM
ANA BEING INCORPORATED INTO THE MID LATITUDE FLOW AND MERGING WITH
A WAVE THAT DEVELOPED OVER KAMCHATKA.

STRONG WINDS OVER THE SOUTHERN PANHANDLE WILL CONTINUE INTO
TUESDAY NIGHT WAS THE FIRST AND SECOND WRAPS MOVE OVER THE REGION.
WINDS WILL INCREASE OVER THE CENTRAL AND COASTAL PANHANDLE AS THE
LOW MOVES NORTHWARD THROUGH THE DAY WITH 850 MB WINDS IN THE 45 TO
55 MPH. EASTERLY OUTFLOW AND GAP WINDS WILL PICK UP THROUGH
TUESDAY WITH GUST IN THE 40 TO 5O KT RANGE DUE TO THE TIGHTENING
GRADIENT BETWEEN THE GULF LOW AND HIGH PRESSURE OVER WESTERN
CANADA. NEW MODEL RUNS HAD THE LOW BIT DEEPER SO WINDS WERE NUDGED
UP FROM PREVIOUS FORECAST. AS OF NOW WINDS SHOW A QUICK DROP OFF
LATE WEDNESDAY INTO THURSDAY AND BEGIN TO SHIFT FROM NORTH TO
SOUTH BY THE WEEKEND. THE BANDED NATURE OF LOW MEANS PRECIPITATION
MAY NOT BE A STEADY THROUGH TUESDAY AND HAVE HIGHER UNCERTAINTY
ON PRECIPITATION TIMING ON WEDNESDAY WHEN MODEL SPREAD ON THE LOW
POSITION STARTS TO INCREASE. NOT MUCH CHANGE IN TEMPS THROUGH THE
WEEK AS 850 MB TEMPS REMAIN BETWEEN 0 AND 2 C. LATER IN THE WEEK AS
THE UPPER LOW DROPS DOWN FORM THE INTERIOR COLDER AIR MASS MOVES
IN SO EXPECTING TEMPS TO DROP FOR THE NORTHERN AND NORTH COASTAL
PANHANDLE WITH POSSIBLE SNOW FALL FOR THESE AREAS.

GOOD INITIALIZATION WITH THE NAM/GEM FOR PRESSURE. THE ECMWF / GFS
ARE NOT FAR OFF BUT DO SHOW DIFFERENCES IN POSITION AND STRENGTH
OF THE LOW. BY WEDNESDAY MODEL SPREAD INCREASES WITH ECMWF
BECOMING THE FIRST OUTLIER. WENT WITH AN ENSEMBLE APPROACH FOR THE
REST OF THE EXTENDED RANGE USING A BLEND OF WPC. FORECAST
CONFIDENCE IS ONLY AVERAGE INITIALLY DUE TO UNCERTAINTY IN TIMING
THE BANDS ROTATING AROUND THE LOW. CONFIDENCE DOES NOT IMPROVE
THROUGH THE WEEK DUE TO THE LARGE MODEL SPREAD.

&&

.AJK WATCHES/WARNINGS/ADVISORIES...
PUBLIC...STRONG WIND FROM LATE TONIGHT THROUGH TUESDAY MORNING FOR AKZ027-
     028.
MARINE...GALE WARNING FOR PKZ036-041-042.
         SMALL CRAFT ADVISORY FOR PKZ012-021-022-031>035-043-051-052.
         SMALL CRAFT ADVISORY DUE TO SEAS FOR PKZ053.

&&

$$

EAL/PRB

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