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000
FXAK67 PAJK 242337
AFDAJK

SOUTHEAST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE JUNEAU AK
337 PM AKDT FRI OCT 24 2014

.SHORT TERM...A LOW ABOUT 150 NM W OF HAIDA GWAII WILL SLOWLY
WEAKEN AND BEGIN TO DRIFT SE SAT. A TROF WILL EXTEND NW FROM THE
LOW INTO THE EASTERN GULF...BUT GRADUALLY WEAKEN THRU SAT. USED
THE 12Z NAM FOR THE TONIGHT AND SAT PERIODS AS IT HAD A GOOD
HANDLE ON THE MAIN FEATURES.

MAIN FORECAST ISSUES WILL BE PRECIP POTENTIAL...WINDS...AND FOG
POTENTIAL. RIGHT NOW A BAND OF SHOWERS IS OVER THE CENTRAL
PANHANDLE...WITH MORE SCATTERED SHOWERS TO THE S. ALSO...A NARROW
BAND OF SHOWERS IS FORMING NEAR PAYA. THE BAND OF SHOWERS OVER THE
CENTRAL AREA WILL DRIFT NNW TONIGHT...EVENTUALLY MOVING OFFSHORE
AND N OF THE MAIN PART OF THE PANHANDLE SAT. THE SMALL BAND OF
SHOWERS DEVELOPING NEAR PAYA WILL REMAIN THERE THIS EVENING THEN
DIMINISH SOMEWHAT LATER TONIGHT. THE SCATTERED SHOWERS OVER THE
SRN HALF OF THE AREA WILL DIMINISH OVER ALL BUT THE FAR SRN AND
ADJACENT COASTAL AREAS TONIGHT. INCREASING NLY FLOW WILL DRY
THINGS OUT OVER MUCH OF THE PANHANDLE DURING THE DAY SAT...BUT
SOME SHOWERS WILL REMAIN OVER THE ERN GULF/NE GULF COAST AREAS.

AS FOR WINDS...STRONGEST WINDS ARE OVER THE SE GULF AND SRN INNER
CHANNELS. THEY HAVE SE 20-30 KT WINDS RIGHT NOW...AND THESE WINDS
WILL SLOWLY SUBSIDE TONIGHT. WINDS WILL PROBABLY DROP BELOW SCA
LEVELS OVER THE SE GULF BY SAT MORNING...AND BY LATE TONIGHT OVER
THE SRN INNER CHANNELS. ALSO HAVE AROUND 20 KT OF E-NE WIND THRU
CROSS SOUND AND WRN ICY STRAIT...AND THIS WILL SLOWLY DIMINISH SAT.
THE MORE N-S CHANNEL WINDS OVER THE NRN HALF OF THE AREA WILL
SLOWLY PICK UP TONIGHT AS GRADIENT ORIENTATION BECOMES MORE
FAVORABLE FOR THOSE CHANNELS...BUT DO NOT EXPECT MORE THAN 20 KT
THERE. FINALLY...LOOKS LIKE A NARROW BAND OF E-SE 15-20 KT WINDS FROM
THE PAYA AREA WWD OVER THE NRN GULF. THIS BAND WILL SLOWLY
DIMINISH THROUGH SAT.

AS FOR FOG POTENTIAL...INCREASING BREAKS IN THE CLOUDS WILL ALLOW
FOR SOME FOG TO FORM OVER THE ERN INNER CHANNELS TONIGHT IN WIND
SHELTERED AREAS. DENSITY OF THE FOG WILL BE HIGHLY VARIABLE
THOUGH DUE TO NEARBY WINDS ALOFT. IF THE DEPTH OF LIGHT WINDS WAS
DEEPER AND MORE WIDESPREAD...WOULD BE A DECENT DENSE FOG EVENT.
THE FOG SHOULD DISSIPATE SAT MORNING.

OTHERWISE...CLOUDS WILL BE DECREASING OVER THE ERN AREAS SAT AS
INCREASING OFFSHORE FLOW DEVELOPS. THIS WILL ALLOW TEMPS TO RISE A
FEW DEGREES HIGHER SAT THAN THEY WERE TODAY.

.LONG TERM...DRIER THAN NORMAL CONDITIONS WILL CONTINUE THROUGH
NEXT WEEK.

 THE START OF THE LONG TERM FORECAST PERIOD WILL FEATURE A WEAK
TROUGH OVER THE NORTHEAST GULF. THIS MEANS PRETTY TRANQUIL WEATHER
OVER THE PANHANDLE FOR SATURDAY NIGHT. EXPECT SCATTERED SHOWERS TO
BECOME ISOLATED WITH DECREASING SKY COVER THROUGH THE NIGHT. ON
SUNDAY AN UPPER LEVEL DISTURBANCE WILL MOVE ACROSS THE NORTHEAST
GULF INTO THE NORTHERN PANHANDLE. THIS WILL CREATE MOSTLY CLOUDY
SKIES AND LIGHT RAIN SHOWERS ACROSS THE AREA THROUGH SUNDAY NIGHT.

 ON THE BACK SIDE OF THIS UPPER LEVEL DISTURBANCE, A SHARP BUT
SKINNY RIDGE OF HIGH PRESSURE WILL BUILD INTO THE AREA ON MONDAY.
AT THE SAME TIME, THE REMNANT OF TROPICAL STORM ANA WILL HEAD EAST
TOWARDS VANCOUVER ISLAND. THE COMBINATION OF THESE WEATHER SYSTEMS
WILL CREATE A NORTHERLY PRESSURE GRADIENT. WITH NORTHEASTERLY
FLOW, DO EXPECT DRY CONDITIONS ACROSS THE NORTHERN PANHANDLE.
THERE WILL STILL BE SOME LINGERING SHOWERS OVER THE EXTREME
SOUTHERN PANHANDLE FROM THE OUTER FRINGES OF FORMER TROPICAL STORM
ANA.

 BEYOND NEXT MONDAY, THE WEATHER PATTERN REMAINS SLOW TO CHANGE.
THERE WILL BE HIGHER PRESSURE OVER THE INTERIOR, WITH LOWER
PRESSURE OVER THE GULF OF ALASKA. THIS PATTERN WILL FEATURE
GENERALLY NORTHEAST FLOW OVER THE AREA, PROMOTING DRIER THAN
NORMAL CONDITIONS. TEMPERATURES SHOULD BE FAIRLY SEASONABLE, WITH
HIGHS IN THE 40S, AND LOWS IN THE LOW TO MID 30S. FOR THE NORTHERN
AREAS, THE OVERNIGHT LOW TEMPERATURES WILL DROP BELOW 32 F FOR
EARLY NEXT WEEK. SNOW WILL MIX IN FOR HIGHER ELEVATION LOCATIONS
AND DURING THE OVERNIGHT AND EARLY MORNING HOURS.

 FORECAST CONFIDENCE IS ABOUT AVERAGE THROUGH THE WEEKEND INTO
EARLY NEXT WEEK. FORECAST CONFIDENCE THEN DECREASES TO BELOW
AVERAGE BEYOND THAT. VARIOUS WEATHER MODELS START TO DIVERGE IN
THEIR SOLUTION STARTING EARLY NEXT WEEK. THEY AGREE THAT THERE
WILL BE A GENERAL AREA OF LOW PRESSURE IN THE GULF OF ALASKA.
HOWEVER, THEY ARE STRUGGLING TO PROVIDE THE DETAILS SUCH AS THE
INDIVIDUAL DISTURBANCES MOVING UP TOWARDS THE PANHANDLE. THESE
DISTURBANCES WILL LEAD TO SIGNIFICANT DIFFERENCES IN WIND AND
PRECIPITATION.

&&

.AJK WATCHES/WARNINGS/ADVISORIES...
PUBLIC...NONE.
MARINE...SMALL CRAFT ADVISORY FOR PKZ033-035-036-041-042.
         SMALL CRAFT ADVISORY DUE TO SEAS FOR PKZ043.

&&

$$

RWT/RCL

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











000
FXAK67 PAJK 241300
AFDAJK

SOUTHEAST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE JUNEAU AK
500 AM AKDT FRI OCT 24 2014

.SHORT TERM...SATELLITE IMAGERY THIS MORNING SHOWING A QUASI
STATIONARY 999 MB LOW OFF THE COAST OF HAIDA GWAII WITH A WEAK
TROUGH OF LOW PRESSURE EXTENDING FROM THE LOW NORTHWESTWARD OVER THE
AK GULF. THIS LOW WILL SHIFT SLIGHTLY TO THE NORTH AND WEAKEN INTO
THE EVENING.

WEAK FRONT/BAND OF PRECIPITATION FROM THIS LOW THAT MOVED OVER THE
PANHANDLE YESTERDAY AFTERNOON AND EVENING IS CURRENTLY EXITING TO
THE NORTH. CLEAR BREAKS BEHIND THIS SYSTEM OVER THE CENTRAL
PANHANDLE RESULTED IN SOME COOLING AND FOG FORMATION. ONE QUARTER
MILE DENSE FOG DEVELOPED OVER THE JUNEAU AIRPORT AND VALLEY WITH
GUSTAVUS AND HOONAH FOG ONLY DROPPING VISIBILITY DOWN TO ONE HALF
MILE OCCASIONALLY. A SECOND FRONT / PRECIPITATION BAND IS NOW
MOVING OVER THE SOUTHERN PANHANDLE AND WILL THEN TRACK NORTHWARD
THROUGH THE DAY AND INTO THE EVENING. THERE IS THUNDER STORM
ACTIVITY OVER THE SOUTHEASTERN QUADRANT OF THE LOW WHICH SHOULD
STAY SOUTH OF OUR MARINE AREA BUT HAVE INCLUDED SLIGHT CHANGE OF
T-STORMS IN CASE SOME CELLS PUSH FURTHER NORTH. THINK THIS SECOND
BAND WILL REMAIN INTACT AS THE PREVIOUS DAYS FRONT DID, THEN DISSIPATE
AS IT PULLS TO THE WEST LATE TONIGHT. RAIN SHOWERS FROM THIS FRONT
WILL NOT PRODUCE MUCH IN THE WAY OF QPF AND MAY AT TIMES FEEL MORE
LIKE LIGHT DRIZZLE. PRECIP AND CLOUD BREAKS BEHIND THE FRONT OVER
THE SOUTHERN PANHANDLE WILL BEGIN LATE TONIGHT WITH PATCHY FOG
DEVELOPING.

WINDS OVER THE SOUTHERN COASTAL AND INSIDE WATERS WILL INCREASE TO
MIN SMALL CRAFT LEVELS AS THE SURFACE LOW MOVES NORTH. SINCE THE
LOW WILL NOT MOVE VERY FAR EXPECTING THESE AREAS OF SMALL CRAFT
WINDS TO REMAIN SOUTH OF FREDERICK SOUND. WINDS PICK UP TO 20 KTS
OVER THE CENTRAL INNER CHANNELS WITH SOME HIGHER EASTERLY GUSTS
FROM CHANNELED TERRAIN AND GAPS DUE TO THE PRESSURE GRADIENT
BETWEEN THE GULF LOW AND WESTERN CANADIAN HIGH PRESSURE. WITH
CLOUD COVER AND RAINFALL DAY TIME HIGHS ONLY EXPECTED TO REACH THE
MID 40S TO LOW 50S. WHILE CLOUD COVER WILL LAST LONGER TONIGHT
THERE IS SOME COOLER AIR ALOFT MOVING IN BEHIND THE LOW WITH
OVERNIGHT TEMPS IN THE UPPER 30S TO LOW 40S.

MODELS STILL SHOWING MORE SPREAD THAN ONE WOULD LIKE TO SEE THIS
EARLY IN THE FORECAST. 00Z ECMWF/GEM HAD GOOD INITIALIZATION WITH
SURFACE PRESSURE FIELD AND WERE USED TO REFRESH INHERITED GRIDS.
CHANGES TO PRESS AND WINDS WERE MINOR. DID LIKE THE NAM/GEM/SREF
POP FIELDS WHICH SHOWED POPS BAND SIMILAR TO THE PREVIOUS DAY SO
POPS ARE NOW BIT HIGHER THIS AFTERNOON AND TONIGHT OVER THE
CENTRAL PANHANDLE. WHILE MODEL AGREEMENT IS NOT GREAT FORECAST
CONFIDENCE IS AVERAGE SINCE EXPECTING A SIMILAR PATTERN TO
YESTERDAYS.

.LONG TERM...MODEL PERFORMANCE HAS BEEN IMPROVED FROM THE
PREVIOUS RUN AND PROVIDES BETTER PREDICTABLE SOLUTIONS THROUGH THE
WEEKEND FOR THE NEAR STATIONARY LOW WEST OF HAIDA GWAII SATURDAY
WEAKENS AND STARTS DRIFTING SOUTHWARD THROUGH SUNDAY. A BROAD WEAK
SURFACE TROUGH WILL EXTEND NORTH FROM THE WEAKENING LOW TO THE
NORTHERN GULF. AN UPPER LEVEL SHORTWAVE TROUGH OVER THE EASTERN
GULF SATURDAY MORNING WILL DRIFT EASTWARD ACROSS THE PANHANDLE TO
THE WESTERN CANADA BY SUNDAY MORNING...FOLLOWED BY A WEAK UPPER
TROUGH MOVES OVER THE PANHANDLE THROUGH MONDAY. AN AMPLIFIED UPPER
RIDGE WILL MOVE EAST ACROSS THE GULF AND THE NORTHERN PANHANDLE
THROUGH THE MID WEEK AS A CLOSED UPPER LOW DIGGING SOUTH FROM
WESTERN ALASKA INTO THE CENTRAL GULF. ANOTHER UPPER RIDGE WILL
BUILD OVER THE BERING SEA AND DRIFT EAST ACROSS THE GULF THROUGH
THE SECOND HALF OF NEXT WEEK. REFRESHED THE INHERITED FORECAST
PACKAGE WITH THE ECMWF THROUGH LATE SUNDAY EVENING THEN USED THE
WPC ENSEMBLE SOLUTIONS FOR THE REMAINING LONG TERM PERIODS.
FORECAST CONFIDENCE ABOUT AVERAGE THROUGH THE WEEKEND THEN FALLS
BELOW AVERAGE FOR THE NEXT WEEK AS MODEL SOLUTIONS DIFFER ON THE
TROPICAL STORM ANA MOVING INTO THE SOUTHERN GULF.

INCREASING OFFSHORE FLOW WILL CONTINUE TO PUSH SHOWERS
DIMINISHING ACROSS THE PANHANDLE THROUGH SUNDAY MORNING...BUT
ANOTHER WEAK UPPER TROUGH MOVING OVER THE PANHANDLE WILL BRING
CHANCE POPS BACK TO THE AREA SUNDAY AFTERNOON INTO THE EVENING
HOURS. MODELS CONTINUE DIVERTING FOR NEXT WEEK AS THEY HANDLE THE
TROPICAL STORM ANA...CURRENTLY RECURVING NORTHEASTWARD OVER
NORTHWEST OF HAWAII. THE LATEST CENTRAL PACIFIC HURRICANE CENTER
PREDICTION MAINTAINS ANA ABOUT THE SAME TROPICAL STORM STRENGTH
THROUGH SUNDAY NIGHT AS IT REACHES NEAR 47N/143W...HEADING TOWARD
HAIDA GWAII THROUGH MONDAY EVENING. THE WPC ENSEMBLE SOLUTION
KEEPS ANA JUST SOUTHWEST OF HAIDA GWAII BY EARLY TUESDAY
MORNING...KEEPING WET WEATHER ACROSS THE SOUTHERN PANHANDLE LATE
MONDAY NIGHT THROUGH WEDNESDAY. THE AMPLIFIED UPPER RIDGE MOVING
EAST ACROSS THE GULF AND THE NORTHERN PANHANDLE WILL KEEP
GENERALLY DRY WEATHER ACROSS THE NORTHERN PANHANDLE UNDER OFFSHORE
LOW TO MID LEVEL FLOW AND ALSO BRING COLD AIR ADVECTION THROUGH
THE MID WEEK.

&&

.AJK WATCHES/WARNINGS/ADVISORIES...
PUBLIC...DENSE FOG ADVISORY UNTIL 9 AM AKDT THIS MORNING FOR AKZ025.
MARINE...SMALL CRAFT ADVISORY FOR PKZ033-035-036-041.
         SMALL CRAFT ADVISORY DUE TO SEAS FOR PKZ042.

&&

$$

PRB/AHN

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











000
FXAK67 PAJK 240000
AFDAJK

SOUTHEAST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE JUNEAU AK
400 PM AKDT THU OCT 23 2014

.SHORT TERM...A DUAL LOW SYSTEM OVER THE SOUTHEAST GULF OF ALASKA
WILL SIMPLIFY THROUGH THURSDAY NIGHT AS THEY CONSOLIDATE INTO A
SINGLE LOW AND THEN STALLS ABOUT 150 NM WEST OF HAIDA GWAII BY
FRIDAY. A LARGE NUMBER OF OPEN CELL FEATURES ARE ROTATING ABOUT
THE SOUTH AND SOUTHEAST SIDE OF THE LOW AND SATELLITE SENSING HAS
AT TIMES IS REPORTING SOME STRIKES AROUND SOUTHERN HECATE STRAIT.
THE FRONTAL FEATURE ASSOCIATED WITH THE EASTERN MOST OF THE DUAL
LOWS IS SHEERING APART OVER THE CENTRAL AND NORTHERN PANHANDLE.
SCATTERED SHOWERS WITH IT ARE NOT DROPPING LARGE RAINFALLS.

WINDS HAVE DIMINISHED AND FOR THE MOST PART ARE UNDER 15 KT IN THE
MARINE WATERS. A FEW GUSTIER CHANNELS HAVE SOME GUSTS TO 25 KT...
AND THE HEAVIER SHOWERS ARE ALSO BRIEFLY PICKING THE WINDS UP...AS
WELL BRINGING SOME BRIEF HEAVY RAINFALL.

THE REGION WITH THE FEWEST CLOUDS LATE THIS AFTERNOON IS WEST OF
CAPE FAIRWEATHER HOWEVER CLOUDS ARE SPREADING WEST. AREAS THAT
MANAGE TO HOLD ONTO A LARGER BREAK IN THE CLOUDS OVERNIGHT MAY
DEVELOP SOME PATCHY FOG BUT AM NOT THINKING THIS IS A MAJOR ISSUE
TONIGHT.

.LONG TERM...LOW NEAR HAIDA GWAII SHOULD WEAKEN TO A TROF THAT
WILL EXTEND NW INTO THE ERN GULF FOR FRI-SAT. LOOKS LIKE A
SHORTWAVE TROF WILL MOVE ACROSS THE AREA FROM THE W SUN/MON...BUT
MODELS DIFFER ON HOW FAR S THE MAIN VORT MAX WILL DIG TO THE W OF
THE AREA. EARLY NEXT WEEK...TS ANA WILL BECOME A FACTOR BUT MODELS
DIFFER ON HOW FAST IT LIFTS NE AND HOW FAR N IT GETS. THE RIDGING
TO THE N SHOULD GENERALLY SUPPRESS THIS FEATURE AS WELL AS OTHER
SRN STREAM SYSTEM THAT MOVES TOWARD THE AREA. LATER ON...MODELS
DIVERGE SOMEWHAT SO CONFIDENCE IN SYSTEM DETAILS DECREASES. USED
BLEND OF THE 00Z ECMWF/12Z GFS/12Z GEM FOR FRI NIGHT-SAT...THEN
JUST USED 00Z ECMWF/12Z GFS FOR SAT NIGHT AND SUN. WENT WITH
LATEST WPC FOR THE MOST PART SUN NIGHT ONWARD.

FOR FRI NIGHT-SAT...MINOR VORT SPOKES WILL KEEP SOME SHOWER ACTIVITY
MOVING NWD INTO THE AREA. HOWEVER...SFC TROF WILL BE DRIFTING WWD
FROM THE PANHANDLE TO THE ERN GULF BY SAT MORNING...AND THIS WILL
ALLOW THINGS TO DRY OUT FROM THE E LATER FRI NIGHT AND SAT OVER
THE ERN INNER CHANNELS. INCREASING NLY LOW LEVEL FLOW AND OFFSHORE
FLOW ALOFT WILL ALLOW FOR MORE SUNSHINE OVER THE ERN AREAS BY SAT
AFTERNOON.

FOR SAT NIGHT-SUN NIGHT...WILL BE WATCHING NEXT SHORTWAVE MOVING INTO
THE AREA FROM THE W. SOME SHOWERS SHOULD STILL BE GOING ON OVER
THE ERN GULF NEAR THE SFC TROF...AND THESE SHOULD INCREASE AND
SPREAD ONSHORE SUN AS SHORTWAVE MOVES CLOSER TO THE AREA AND LOWER
LEVEL FLOW TURNS MORE ONSHORE. MOST OF THE SHOWERS WILL BE OVER
THE N HALF OF THE AREA IT APPEARS THRU SUN NIGHT.

FOR EARLY NEXT WEEK...LOOKS LIKE MOST OF THE PRECIP THREAT WILL BE
OVER THE SRN PART OF THE AREA AS SYSTEM APPROACHES FROM THE SW.
DID ADJUST POPS FROM WPC TO SHOW DRIER CONDITIONS OVER THE N BASED
ON FAIRLY STRONG OFFSHORE FLOW AND TRANSIENT UPPER RIDGE MOVING
THRU THE NRN AREA FOR MON-TUE. ALSO...LOOKS COOLER DURING EARLY TO
MID NEXT WEEK SO DID LOWER TEMPS SOME ESPECIALLY OVER THE N. SOME
DISAGREEMENT ON HOW COLD IT GETS AND POTENTIAL FOR ANY SNOW AS
ANOTHER SYSTEM APPROACHES FROM THE W TOWARD MIDWEEK. FOR
NOW...KEPT PTYPE AS RAIN FOR NEAR SEA LEVEL AREAS BUT LATER SHIFTS
MAY NEED TO ADJUST THIS IF MODELS TREND COLDER.

&&

.AJK WATCHES/WARNINGS/ADVISORIES...
PUBLIC...NONE.
MARINE...SMALL CRAFT ADVISORY FOR PKZ036-041.
         SMALL CRAFT ADVISORY DUE TO SEAS FOR PKZ042-043.

&&

$$

BEZENEK/RWT

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









000
FXAK67 PAJK 231230
AFDAJK

SOUTHEAST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE JUNEAU AK
430 AM AKDT THU OCT 23 2014

.SHORT TERM...SATELLITE IMAGERY THIS MORNING SHOWING TWO 985 MB
LOW PRESSURE SYSTEMS IN THE NORTHER PACIFIC ROTATING AROUND EACH
OTHER. THE LOW LOCATED WEST OF HAIDA GWAII WILL AFFECT OUR AREA
WITH A WEAK FRONTAL BAND CURRENTLY OVER THE SOUTHERN PANHANDLE
MOVING NORTHWARD. THIS LOW WILL CONTINUE TO PROGRESS WESTWARD
MERGING WITH THE THE SECOND LOW LATER IN THE DAY. THE RESULTING
CIRCULATION WILL WEAKEN AS IT MOVES OFF THE COAST OF HAIDA GWAII
AGAIN AND BECOME QUASI STATIONARY.

CLEAR BREAKS OVER THE NORTHERN PANHANDLE DUE TO OFFSHORE FLOW HAS
RESULTED IN FOG DEVELOPMENT FOR LOCATIONS NORTH OF FREDERICK SOUND
AND TEMPS DROPPED DOWN TO FREEZING DUE TO RADIATIONAL COOLING.
LOCAL VISIBILITIES HAVE DROPPED BELOW 1 MILE AT TIMES. CLOUDS WILL
INCREASE THROUGH THE MORNING AS THE FRONT ADVANCES NORTHWARD.
RAIN SHOWERS OVER THE SOUTHERN PANHANDLE HAVE BEEN LIGHT BUT DO
EXPECT MORE SHOWER BANDS TO MOVE OVER THE SOUTHERN REGION TODAY
AND AGAIN TONIGHT AS THE REFORMED LOW MOVES BACK NEAR HAIDA GWAII.
SHOWERS WILL DEVELOP OVER THE CENTRAL AND NORTHERN PANHANDLE LATER
IN THE DAY AS FRONT MOVES NORTH. THE FRONT WILL BE SHEARING APART
WHILE IT MOVES NORTH AND FORCING MECHANISMS WEAKEN SO SHOWERS WILL
BE SCATTERED. WITH COOLER AIR ALOFT AND WARM SEA SURFACE
TEMPERATURES PRODUCING CONVECTIVE ATMOSPHERE WITH CAPE AROUND 200
TO 400 J/KG AND LIFTED INDEX OF 0 TO -2C SOUTH OF THE LOW CENTER SO HAVE
INCLUDED SLIGHT CHANCE OF THUNDER STORMS OVER THE SE AK GULF.

OVER THE SOUTHERN COASTAL WATERS SMALL CRAFT WINDS AND SEAS AROUND
10 FT WILL DIMINISH THROUGH THE MORNING AS THE LOW PULLS OFF TO THE
WEST. WINDS AND SEAS WILL PICK UP AGAIN LATE TONIGHT AS THE
REFORMED LOW MOVES BACK IN. NORTHERLY SMALL CRAFT WINDS OVER
NORTHERN AND SOUTHERN LYNN CANAL EARLY THIS MORNING DUE TO
PRESSURE GRADIENT BETWEEN THE LOW IN THE SE GULF AND HIGH PRESSURE
OVER THE YUKON. ELSEWHERE WINDS IN THE 20 KT RANGE WITH SOME
EASTERLY GAP AND OUTFLOW WINDS BETWEEN THE SE GULF LOW AND HIGH
OVER BRITISH COLUMBIA. WINDS WILL WEAKEN THROUGH THE MORNING AS THE LOW
PULLS OFF THE WEST. WEAK GRADIENT TONIGHT WILL RESULT IN WINDS
GENERALLY LESS THAN 15 KTS BUT WITH INCREASING WINDS OVER THE FAR
SOUTHERN PANHANDLE AS THE REFORMED LOW NEARS HAIDA GWAII.

MODELS HAVE NOT BEEN HANDLING THESE TWO LOW PRESSURE SYSTEMS IN
THE N PACIFIC VERY WELL SO FORECAST CONFIDENCE IS BELOW AVERAGE. LOTS OF
SHIFTING IN STRENGTH AND POSITION OF THE LOW CENTERS AS THEY ROTATE
AROUND EACH OTHER. MODEL CHOICE WAS MAINLY PICKING ONES THAT WERE
IN BETTER AGREEMENT AND HAVE SHOWN LESS CHANGE RUN TO RUN. DECIDED
TO USE A BLEND OF 00Z ECMWF/NAM FOR THE SHORT TERM FORECAST WHICH
DID SHIFT THE LOW BACK EAST SLIGHTLY THIS MORNING AND ALTERED SOME
WIND SPEEDS. MODELS ALSO HAD A LARGE SPREAD IN TIMING PRECIP BANDS
SO WENT WITH A BLEND OF NAM/GFS/SREF, WITH BIT MORE CONFIDENCE IN
THE NAM.

.LONG TERM...MID RANGE MODELS STRUGGLE A LITTLE ON FRIDAY INTO
SATURDAY AS THE CONSOLIDATING LOW BECOMES QUASI-STATIONARY NEAR THE
COAST OF HAIDA GWAII IN CONJUNCTION OF ANOTHER WEAK LOW FORMING
OVER THE NORTHERN GULF ON SATURDAY. A SURFACE TROUGH WILL BECOME A
BIT ACTIVE THROUGH THE WEEKEND BETWEEN THE NORTHERN GULF LOW AND
THE LOW OFF THE COAST OF HAIDA GWAII. SCATTERED SHOWERS WILL
CONTINUE ALONG THE TROUGH SATURDAY...THEN EXPECT INCREASING
OFFSHORE LOW LEVEL FLOW ACROSS THE NORTHERN AREAS FOR GENERALLY
DRY WEATHER SUNDAY WHILE THE SOUTHERN AREAS STAY UNDER SCATTERED
SHOWERS. NONE OF THE MODEL SOLUTIONS GIVEN FOR FRIDAY AND SATURDAY
HANDLES THE SYNOPTIC PATTERN WELL. DECIDED TO MAKE A TEMPORAL
TRANSITION FROM THE SHORT TERM FORECAST OF NAM AND ECMWF BASED
SOLUTIONS AND MADE SMOOTH CONNECTION TO THE WPC ENSEMBLE GUIDANCE
SUNDAY ONWARD.

MODELS CONTINUE DIVERTING FOR NEXT WEEK AS THEY HANDLE THE
TROPICAL STORM ANA...CURRENTLY MOVING SLOWLY NORTH-NORTHWESTWARD
OVER NORTHWEST OF HAWAII. THE JTWC PREDICTS ANA WILL WEAKEN AND
RE-CURVE NORTHEASTWARD BY FRIDAY MORNING NEAR 30N/170W...THEN
HEADING TOWARD HAIDA GWAII THROUGH MONDAY EVENING. ANA WILL
CONTINUE TO WEAKEN AND BECOME AN EXTRATROPICAL SYSTEM BY SUNDAY
EVENING. THE WPC ENSEMBLE SOLUTION WILL KEEP THE EXTRATROPICAL
SYSTEM MOVING OVER HAIDA GWAII WITH WET WEATHER ACROSS THE
SOUTHERN PANHANDLE TUESDAY AND WEDNESDAY. NO SIGNIFICANT
WINDS/SEAS ARE EXPECTED...EXCEPT FRIDAY NIGHT WHEN THE NEAR-
STATIONARY LOW OFF THE COAST OF HAIDA GWAII PRODUCES SMALL CRAFT
LEVEL WINDS/SEAS OVER THE SOUTHERN OUTER WATERS. TEMPERATURES WILL
REMAIN WITHIN NORMAL RANGE OVER THE NORTHERN PANHANDLE WHILE
EXTRATROPICAL SYSTEM MAINTAINS SOUTHERN AREAS WARMER THAN NORMAL.
FORECAST CONFIDENCE REMAINS BELOW AVERAGE.

&&

.AJK WATCHES/WARNINGS/ADVISORIES...
PUBLIC...NONE.
MARINE...SMALL CRAFT ADVISORY FOR PKZ012-013-041-042.
         SMALL CRAFT ADVISORY DUE TO SEAS FOR PKZ022-043-051-052.

&&

$$

PRB/AHN

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 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










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