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000
FXAK67 PAJK 192340
AFDAJK

SOUTHEAST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE JUNEAU AK
340 PM AKDT SAT APR 19 2014

.SHORT TERM...AFTERNOON SATELLITE IMAGE SHOWS A 976 MB LOW ABOUT
200 MILES WEST-SOUTHWEST OF HAIDA GWAII WITH AN OCCLUDED FRONT
STRETCHING EAST ACROSS DIXON ENTRANCE THEN SOUTHEAST OVER BRITISH
COLUMBIA COAST. BETWEEN THE LOW AND PERSISTING HIGH PRESSURE AREA
IN YUKON...NORTHERLY PRESSURE GRADIENT REMAINS AND PRODUCES
NORTHERLY WINDS OVER THE NORTHERN INNER CHANNELS. AHEAD OF THE
INCOMING FRONTAL PASSAGE...ADVANCED MULTIPLE CLOUD LAYERS DRIFT
NORTH ACROSS SOUTHEAST ALASKA WITH RAIN OVER THE SOUTHERN
PANHANDLE. GUSTY EAST TO SOUTHEAST WINDS PROPAGATE FROM BARANOF
ISLAND TO JUNEAU AREA SOUTH TO WRANGELL...KLAWOCK AND KETCHIKAN
AREAS. NORTHERNMOST AREAS REMAIN MOSTLY CLOUD FREE THIS
AFTERNOON. TEMPERATURES SOAR UP TO THE LOWER TO MID 50S.

MODELS REMAIN IN FAIR AGREEMENT WITH THE 976 MB LOW CONTINUES
MOVING NORTHWARD INTO THE SOUTHEASTERN GULF THROUGH THIS EVENING
THEN DRIFT INTO THE CENTRAL GULF BY SUNDAY MORNING. THE OCCLUDED
FRONTAL PASSAGE WILL CONTINUE TO MOVE OVER THE CENTRAL PANHANDLE
AND NORTHEASTERN GULF THROUGH SUNDAY. REFRESHED THE INHERITED
FORECAST PACKAGE WITH THE MOST PERSISTENT ECMWF SOLUTIONS FOR
PRESSURE FIELDS AND BLENDED THE POPS AND QPF FIELDS WITH THE ECMWF
AND GEM FOR TONIGHT AND SUNDAY.

GALE FORCE WINDS WILL CONTINUE TO AFFECT THE OFFSHORE WATERS
THROUGH TONIGHT AND SOUTHERN TO CENTRAL OUTSIDE WATERS THROUGH
LATE TONIGHT. AS THE LOW CONTINUES TO DRIFT NORTHWESTWARD INTO THE
CENTRAL GULF...STRONG GUSTY WINDS WILL CONTINUE TO AFFECT THE
SOUTHWESTERN PANHANDLE THROUGH SUNDAY MORNING. STRONG WINDS WILL
CONTINUE OVER BARANOF ISLAND THROUGH THIS EVENING. LIKELY TO
CATEGORICAL POPS WILL MOVE NORTH ACROSS SOUTHEAST ALASKA THIS
EVENING INTO SUNDAY MORNING...REACHING UP TO GLACIER BAY AND
JUNEAU AREAS. THE RAIN BANDS WILL THEN SHEAR APART WITH HIGHER
POPS REMAINING OVER THE NORTHERN PANHANDLE...WHILE SOUTHERN AREAS
WAITING FOR THE SECONDARY WAVE MOVING INTO THE AREA FROM THE
SOUTH. EXPECTED OVERNIGHT TEMPERATURES WILL NOT AS COLD AS LAST
NIGHT DUE TO INCREASING CLOUDS AND POPS. MID 30S ARE EXPECTED
ALONG THE NORTHEASTERN GULF COAST...UPPER 30S TO AROUND 40 IN THE
NORTHERN AND CENTRAL PANHANDLE...AND MOSTLY IN THE LOWER 40S OVER
THE SOUTHERN AREAS. EASTER SUNDAY DAYTIME HIGHS WILL BE IN
SEASONAL RANGE OF UPPER 40S TO THE LOWER 50S.



&&

.LONG TERM...THE LOW OVER THE GULF ALASKA THAT HAD BEEN ROTATING
ABOUT GULF WILL TAKE ONE LAST CIRCLE MOVING FROM THE WEST CENTRAL
GULF SUNDAY NIGHT THEN TO THE SOUTHEAST TO BE ABOUT 300 NM SW OF
HAIDA GWAII MONDAY EVENING. THE SECOND WAVE THAT WAS TRAILING THE
MAIN FRONTAL BAND WILL BE LIFTING NORTHWARD ALONG THE OUTER COAST
OF THE PANHANDLE AND FOLLOWING THE WESTERN TURN THE PREVIOUS ONES
HAD. THE FRONT IS FALLING APART AS IT MOVES INTO THE SOUTHERN
PORTION OF THE PANHANDLE AND WILL LEAVE SHOWERS AS THE WEATHER
SUNDAY INTO THE MONDAY UNTIL THEY FALL APART.

MAJORITY OF THE PANHANDLE FROM MON TO THE END OF THE WEEK WILL SEE
ANY OF THE SHOWERS TAPER OFF AND THEN LEAVE A PARTLY TO MOSTLY
CLOUDY SKY ACROSS THE REGION. THE AREAS THAT GET SOME ADEQUATE
RAIN FALL AND THE BREAKS IN THE SKY COVER MAY SEE THE DEVELOPMENT
OF PATCHY FOG. HAVE LEFT MENTION OUT FOR NOW BUT SOMETHING WE WILL
KEEP AN EYE ON.

MEANWHILE THE STRONG LOW ALONG THE ALEUTIANS WILL BE MOVING VERY
SLOWLY EASTWARD WILL THE FRONTAL BAND MOVE EAST. THE NORTHERN
PORTION LOOKS TO BE JUST SHEARING OUT AS THE TRIPLE POINT
CONTINUES EASTWARD. IT SEEMS THAT THIS WILL STAY SOUTH OF THE
FORECAST AREA BUT COULD BE TRYING TO SPREAD SOME CLOUDS AND
PERHAPS RAIN INTO THE SOUTHERN PANHANDLE BY NEXT WEEKEND.

OVERALL UPCOMING WEEK LOOKS DRY FOR SOUTHEAST ALASKA...WITH NO
STRONG GRADIENTS FOR WIDESPREAD STRONG WINDS THOUGH LOCAL EFFECTS
WILL BOOSTING SOME VALUES AROUND THE PANHANDLE. CONFIDENCE IS
AVERAGE FOR THE FORECAST PERIOD.




.AJK WATCHES/WARNINGS/ADVISORIES...
PUBLIC...STRONG WIND THROUGH SUNDAY MORNING FOR AKZ027.
         STRONG WIND UNTIL 10 PM AKDT THIS EVENING FOR AKZ023.
MARINE...GALE WARNING FOR PKZ036-041>043-051-052.
         SMALL CRAFT ADVISORY FOR PKZ011-013-021-022-031-033>035.

&&

$$

AHN/BEZENEK








000
FXAK67 PAJK 191342
AFDAJK

SOUTHEAST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE JUNEAU AK
542 AM AKDT SAT APR 19 2014

.SHORT TERM...RAIN HAS BEGUN TO SPREAD INTO THE SOUTHERN
PANHANDLE WITH HIGHER CLOUDS MOVING NORTH FROM THE BIG...BUT
RELATIVELY SLOW MOVING GALE FORCE LOW EDGING NORTHWARD INTO THE
EASTERN GULF. GALE FORCE WINDS ARE APPEARING IN DIXON ENTRANCE AT
BUOY 145...IN ADDITION TO CAPE DECISION CLIMBING TO GALE FORCE,
ALTHOUGH THIS PROBABLY AN OUTLIER FOR THE AREA AT THIS POINT.
BOUNDARY LAYER WINDS ARE RISING IN FRONT OF THIS STORM, AND EVEN
TAKING 30 PERCENT OF THE MAGNITUDE OF THESE OFF TO TRANSLATE AT
THE SURFACE, WE STILL WERE LEFT WITH GALES AT CLARENCE STRAIT AND
SOUTHERN CHATHAM STRAIT. THESE WINDS HAVE PRESENTED A FORECAST
CHALLENGE THE LAST FEW DAYS...ESPECIALLY FOR SATURDAY. THE
ORIENTATION IS NOT THE GREATEST FOR STRONG WINDS, BUT THEN AGAIN,
IT IS DIFFICULT TO IGNORE THE WINDS SCREAMING A SHORT WAYS ALOFT.
MANY OF OUR AIRPORT LOCATIONS MAY NOT VERIFY DURING THIS EVENT,
BUT SOME AREAS IN ZONES 27 AND 28 WILL HAVE SOME GOOD GUSTS FROM
THIS SETUP. METLAKATLA WILL GET MORE WIND THAN KETCHIKAN.
CONFIDENCE GROWS FOR STRONG WINDS THIS EVENING AS A FRONTAL
BOUNDARY CROSSES THE SOUTHERN PANHANDLE TO MOVE NORTH INTO THE
CENTRAL PANHANDLE. THE GRADIENT SETUP IS BETTER FOR SOUTHEAST
WINDS AT THE SURFACE, AND THUS AM MORE CONFIDENT ABOUT GALE FOR
CLARENCE...AND DID ADD SOUTHERN INNER CHANNELS AND BARANOF ISLAND
FOR STRONG WIND DURING THIS TIME PERIOD. KETCHIKAN WILL BLOW
STRONGEST THIS EVENING. SOUTHERLY WINDS WILL REACH ALL THE WAY
INTO LYNN CANAL BY LATE TONIGHT AS THE REMNANTS OF THE FRONT
SPREAD NORTHWARD, BUT THE EFFECTS/WINDS WILL BE WEAKER TO THE
NORTH.

 AS RAIN FALLS OVER THE SOUTHERN AREAS...THE NORTHERN ZONES WILL
SEE SOME HIGHER CLOUDS TODAY. MODELS ARE DETERMINING HIGHER
CLOUDS SPREADING NORTHWARD, BUT FEEL THAT IN THE JUNEAU/GUSTAVUS
AREA AND POSSIBLY POINTS FURTHER SOUTH, PEOPLE OUTSIDE WILL
EXPERIENCE SOME VARYING AMOUNTS OF SUNSHINE, SO WORDED THINGS
OPTIMISTICALLY AS PARTLY SUNNY. RAIN WILL HOLD OFF NORTH OF
FREDERICK SOUND UNTIL TONIGHT WITH THE RAIN SPREADING INTO
JUNEAU/GUSTAVUS AREA LATE TONIGHT. DID DECIDE TO WORD THE RAIN AS
LIGHT FROM JUNEAU NORTHWARD...AS THE LOW POSITIONING IN THE GULF
WILL BE HARD PRESSED TO DELIVER A BIG SOAKER OF ANY SORT. COULD
SEE IT BEING PERIODS OF SPRINKLES.

 ECMWF CONTINUES TO PERFORM WELL WITH THE SYSTEM. DID LEND A
LITTLE HELP FROM THE GEM FOR POPS/QPF. FORECAST CONFIDENCE ON THE
GOOD SIDE OF AVERAGE.

.LONG TERM...UPPER LOW OVER THE NE PAC AND SRN GULF WILL SHIFT
EWD AND WEAKEN THRU EARLY NEXT WEEK. WEAK UPPER HIGH WILL DEVELOP
OVER INTERIOR AK BY EARLY NEXT WEEK. WEAK UPPER TROF WILL DRIFT
NWD INTO THE SRN AREA BY MIDWEEK. AT THE SFC...A FAIRLY LARGE LOW
WILL BE HEADING SE OUT OF THE GULF SUN NIGHT. A SMALLER LOW LOOKS
LIKE IT WILL MOVE N INTO THE SE GULF SUN NIGHT THEN CURVE WWD INTO
THE NRN GULF AND WEAKEN MON. A WEAK SFC RIDGE WILL DEVELOP OVER
THE ERN GULF AND NRN SE AK BY LATE MON. USED THE 00Z ECMWF FROM
SUN THRU MON NIGHT...THEN TRANSITIONED TO LATEST WPC BY TUE NIGHT.

 FOR SUN-SUN NIGHT...TAIL END OF A WEAKENING OCCLUDED FRONT WILL
MOVE N THRU THE NRN AREA SUN MORNING. THIS FRONT WILL HAVE SOME
PRECIP  WITH IT ALTHOUGH THE AREAS CLOSER TO THE COAST MTNS WILL
SEE LESS PRECIP DUE TO ELY FLOW. THIS PRECIP SHOULD DIMINISH SUN
AFTERNOON.  MORE PRECIP SHOULD REACH THE SRN AREA LATER SUN
MORNING AND EARLY AFTERNOON AS A LOW MOVES N TOWARD THE SE GULF.
THIS SYSTEM MAY ALSO BRING ANOTHER ROUND OF STRONG WINDS TO THE
SRN PANHANDLE SUN AFTERNOON AND NIGHT AS WELL AS 30-35 KT WINDS
FOR THE SE GULF AND SRN INNER CHANNEL MARINE AREAS.
HOWEVER...GIVEN THE SMALL SIZE OF  THE SYSTEM...THESE WINDS WILL
NOT LAST MORE THAN A FEW HOURS IN MOST PLACES.

 FOR MON AND MON NIGHT...SMALL LOW CURVES INTO THE NRN GULF...AND
PRECIP SHOULD DIMINISH OVER MUCH OF THE MAIN PART OF THE
PANHANDLE MON. MAY BEGIN TO SEE SOME CLEARING OVER THE AREA MON
NIGHT AS WEAK RIDGE BUILDS OVER THE AREA.

 FOR TUE ON OUT...SE AK WILL GENERALLY BE IN BETWEEN SYSTEMS TO
THE SE AND W OF THE AREA. MAY SEE MINOR PRECIP THREATS FOR THE
SRN AREA DURING THIS TIME DUE TO PROXIMITY OF A WEAK SYSTEM TO
THEIR SE. THE NRN AREA WILL LIKELY SEE A DECENT AMOUNT OF
SUNSHINE TUE. HAVE ALLOWED MORE CLOUDS TO MOVE IN FROM THE S TUE
NIGHT AND WED AS WEAK UPPER TROF MOVES IN...BUT THIS MAY BE
OVERDONE AS THERE MAY BE LITTLE LOW LEVEL REFLECTION WITH IT. A
SYSTEM MAY TRY TO MOVE UP FROM THE S FOR LATE WEEK BUT MODELS ARE
IN POOR AGREEMENT BY THIS TIME. KEPT HIGHEST POPS OVER THE S FOR
LATE WEEK BUT LIMITED TO HIGH CHANCE LEVELS.

.AJK WATCHES/WARNINGS/ADVISORIES...
PUBLIC...STRONG WIND FROM 1 PM AKDT THIS AFTERNOON THROUGH LATE TONIGHT
     FOR AKZ027.
         STRONG WIND FROM THIS EVENING THROUGH LATE TONIGHT FOR AKZ023-
     028.
MARINE...GALE WARNING FOR PKZ033-036-041>043-051.
         SMALL CRAFT ADVISORY FOR PKZ012-013-021-022-032-034-035-052.

&&

$$

JWA/RWT







000
FXAK67 PAJK 182338
AFDAJK

SOUTHEAST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE JUNEAU AK
338 PM AKDT FRI APR 18 2014

.SHORT TERM...SHOWER ACTIVITY LEFT OVER FROM LAST NIGHT HAS
CONTINUED THROUGH THE EARLY AFTERNOON, BUT HAS GENERALLY
DIMINISHED AND SOME NICE BREAKS IN THE CLOUD COVER ARE EVIDENT IN
BOTH SATELLITE IMAGERY AND WEB CAMERAS. FARTHER SOUTH AND
OFFSHORE INTO THE CENTRAL GULF, A CIRRUS CLOUD SHIELD IS
ADVANCING NORTH AND EAST AHEAD OF THE NEXT LOW AND ASSOCIATED
FRONT. THIS SYSTEM IS QUITE LARGE AND VERY IMPRESSIVE IN ALL
THREE OF THE MAJOR SATELLITE CHANNELS. MODEL DATA IS DEPICTING AN
OBLONG LOW WITH MULTIPLE CENTERS GETTING DOWN INTO THE LOW 970S
THIS EVENING BEFORE THE FRONT STARTS TO IMPACT THE SOUTHERN OUTER
COAST. MULTIPLE CENTERS NOT VISIBLE ON SATELLITE IMAGERY YET, BUT
WHAT WILL EVOLVE INTO THE EASTERN CENTER IS CLEARLY THE DOMINANT
FEATURE. VERY PRONOUNCED DRY SLOT NOTED IN WATER VAPOUR IMAGERY
SUGGESTING SIGNIFICANT POTENTIAL FOR FURTHER DEVELOPMENT. DID NOT
BACK DOWN AT ALL ON PREVIOUS WIND FORECAST AND WITH THE
APPEARANCE OF THE DRY SLOT, MORE WIND MAY BE NECESSARY IN
SUBSEQUENT FORECASTS. AS IT IS, HAVE A STRONG WIND HEADLINE OUT
FOR THE SOUTHERN OUTER COAST FOR LATE TONIGHT AND AGAIN TOMORROW
AFTERNOON. COASTAL MARINE ZONES FROM CAPE FAIRWEATHER SOUTH
FEATURE EASTERLY GALES TO 40 KTS WITH A 35KT GALE FOR CLARENCE
STRAIT. SMALL CRAFT ADVISORIES FOR MOST OF THE REMAINING MARINE
ZONES.

THE FRONT ITSELF LOOKS LIKE IT WILL TEMPORARILY STALL OVER THE
SOUTHERN PANHANDLE AS THE TWO LOW CENTERS FUJIWHARA AROUND EACH
OTHER, BUT NORTHWARD PROGRESS LOOKS LIKE IT WILL RESUME DURING THE
BEGINNING OF THE EXTENDED RANGE FORECAST PERIOD. CONSEQUENTLY,
HAVE A DRY SHORT TERM FORECAST FOR MUCH OF THE PANHANDLE ONCE
SHOWER ACTIVITY DRIES UP LATER THIS EVENING. FOR SOUTHERN
LOCATIONS, QPF VALUES NOT OVERLY EXCESSIVE, EVEN WITH THE FRONT
STALLED, 24 HOUR RAINFALL TOTALS RANGING FROM 0.25 INCHES TO
AROUND 0.44 INCHES.

CLOUD COVER TODAY HAS PREVENTED SIGNIFICANT DAYTIME HEATING WITH
HYDER BEING THE ONLY LOCATION TO SEE 50 DEGREES AS OF EARLY THIS
AFTERNOON. PARTLY CLOUDY CONDITIONS OVER THE PANHANDLE TONIGHT
WILL BE A MOVING TARGET, SO JUST HOW MUCH RADIATIONAL COOLING ANY
ONE PARTICULAR LOCATION EXPERIENCES WILL BE HIGHLY VARIABLE. MOS
GUIDANCE WAS VERY LOW WITH VALUES DOWN TO THE MID 20S FOR NORTHERN
LOCATIONS. DID NOT THINK THIS TO BE REALISTIC, SO BLENDED ECMWF
AND GEM FOR OVERNIGHT LOWS, THEN ADJUSTED TO REFLECT PROJECTED MAX
DEW POINTS FOR TODAY AND EXPECTED LOW LEVEL WARM AIR ADVECTION
FROM THE SOUTH FOR TONIGHT. ECMWF TEMPERATURE CURVE EXHIBITED A
SLOW WARMING TREND ALL NIGHT, BUT KEPT WITH A NORMAL DIURNAL
TREND. CLOUD COVER WILL BUILD BACK IN FROM THE SOUTH TOMORROW, SO
OVERLY WARM MAX TEMPS FOR TOMORROW - AT OR SLIGHTLY ABOVE NORMAL
FOR LATE APRIL.

NO CHANGES TO PRESSURE OR WIND FIELDS. BLENDED ECMWF, GEM, AND
GFS AT TIMES FOR POP AND QPF. TEMPS AS DISCUSSED ABOVE. FORECAST
CONFIDENCE IS AVERAGE TO SLIGHTLY ABOVE AVERAGE.


&&

.LONG TERM...THE LOW PATTERN IN THE GULF BECOMES A SHADE MORE
COMPLEX AS THE LOW RE-CURVES TO THE NORTHWEST GULF OF ALASKA AS A
SECONDARY SHORT WAVE DRIVES SOUTHEAST ON THE WEST SIDE OF THE
UPPER LEVEL LOW IN THE GULF. THIS DIGGING TROUGH WILL MOVE THE
GULF LOW SOUTHEASTWARDS EARLY NEXT WEEK (MONDAY). WITH THE LOW
DISSIPATING AND MOVING OUT OF THE GULF SOUTHEAST ALASKA. EXPECT
SHOWERS TO PERSIST THROUGH SUNDAY...ALTHOUGH FOR SATURDAY NIGHT
THE NORTHERN PANHANDLE MAY HAVE SUFFICIENT OFFSHORE FLOW TO DELAY
OR LIMIT THE AMOUNT OF RAIN THAT MAY FALL. A SECONDARY TRAILING
TROUGH WILL SPREAD EXTRA MOISTURE ACROSS THE AREA FOR LATE SUNDAY
AND AND MONDAY.

AS THE NEXT FEATURE SPREADS ITS FRONTAL BAND ACROSS THE WESTERN
GULF OF ALASKA THROUGH THE FIRST HALF OF NEXT WEEK. SOUTHEAST
ALASKA LOOKS TO BE DRY THROUGH MUCH OF THE WEEK. I DO NOT EXPECT
MAJOR CLEARING AND SUNSHINE NEXT WEEK AFTER THE RAINS TAPER OFF AS
THE UPPER LEVEL FLOW IS SOUTHERLY OR SOUTHEASTERLY.


CONFIDENCE IS AVERAGE THROUGH THE FORECAST PERIOD. ONLY MINIMAL
CHANGES TO THE TEMPERATURES AND A MINOR REFRESHING OF THE WINDS
AND RAIN CHANCES THROUGH THE EXTENDED TIME FRAMES.


&&

.AJK WATCHES/WARNINGS/ADVISORIES...
PUBLIC...STRONG WIND FROM 1 AM AKDT SATURDAY THROUGH SATURDAY MORNING FOR
     AKZ027.
         STRONG WIND FROM SATURDAY AFTERNOON THROUGH SATURDAY EVENING FOR
     AKZ027.
MARINE...GALE WARNING FOR PKZ036-041>043.
         SMALL CRAFT ADVISORY FOR PKZ012-013-021-022-033>035-051-052.

&&

$$

FRITSCH/BEZENEK








000
FXAK67 PAJK 181338
AFDAJK

SOUTHEAST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE JUNEAU AK
538 AM AKDT FRI APR 18 2014

.SHORT TERM...SATELLITE IMAGERY THIS MORNING SHOWING AN OPEN
WAVE TROUGH MOVING INTO THE YUKON THAT IS THE REMNANTS OF THE LOW
PRESSURE SYSTEM FROM THURSDAY. SHOWER ACTIVITY OVER THE PANHANDLE
IS DIMINISHING FROM SOUTH TO NORTH THIS MORNING, STILL HAVE A
500 MB VORT MAX CROSSING THE CENTRAL AND NORTHERN PANHANDLE EARLY
THIS AFTERNOON WHICH WILL KEEP SCATTERED SHOWERS INTO THE
EVENING. SKIES WILL START TO SEE SOME CLEAR BREAKS DEVELOPING
THROUGH THE DAY, HOWEVER NOT EXPECTING COMPLETELY CLEAR SKIES DUE
TO MID LEVEL DISTURBANCES TODAY AND CIRRUS SHIELD FROM THE
ADVANCING LOW TONIGHT. HIGH PRESSURE RIDGE CURRENTLY BUILDING
OVER THE PANHANDLE WITH SOUTHERLY PUSH INCREASING WINDS OVER THE
CENTRAL AND NORTHERN INNER CHANNELS. THESE SOUTHERLY WINDS WILL
DROP DOWN THROUGH THE DAY AS THE RIDGE MOVES EASTWARD INTO
BRITISH COLUMBIA AS A GALE FORCE LOW IN THE NORTH PACIFIC MOVES
TOWARDS THE SOUTHEAST GULF. AS THE LOW MOVES IN WINDS OVER THE AK
GULF WILL INCREASE TO EASTERLY 35 TO 40 KTS FOR THE SOUTHERN
PORTIONS AND 25 TO 30 KTS TO THE NORTH. INNER CHANNEL WINDS FOR
PINTS SOUTH OF FREDERIC SOUND WILL REMAIN SOUTHERLY BUT INCREASE
THROUGH THE NIGHT WITH GALES DEVELOPING OVER CLARENCE STRAIT.
POINTS NORTH OF FREDERICK SOUND WILL SHIFT TO THE NORTH AS THE
PRESSURE GRADIENT DEVELOPS. THE ADVANCING LOW AND FRONT WILL MOVE
RAIN INTO THE FAR SOUTHERN PANHANDLE AGAIN LATE FRIDAY NIGHT
WHILE THE OFF SHORE FLOW FOR THE CENTRAL AND NORTHERN PANHANDLE
WILL CREATE A DRYING TREND. TEMPERATURES WILL BE SEASONABLY
NORMAL IN THE UPPER 40S TO LOW 50S TODAY AND IN THE LOW TO UPPER
30S TONIGHT.

 GOOD MODEL AGREEMENT THIS MORNING WITH ECMWF/NAM HAVING THE BEST
CONTINUITY AND INITIALIZATION. USED SOME WRF FOR WINDS OVER THE
INNER CHANNELS, ESPECIALLY FRIDAY NIGHT WITH THE STRONGER WINDS
DEVELOPING FOR THE SOUTHERN REGIONS. ECMWF KEPT IN HIGHER POPS
BIT TOO LONG SO USED MORE NAM/GFS. FORECAST CONFIDENCE IS ABOVE
AVERAGE.

 .LONG TERM...GALE FORCE LOW MENTIONED IN THE SHORT-TERM WILL
ENTER THE EASTERN GULF SATURDAY AFTERNOON WITH GALE FORCE
EASTERLIES/SOUTHEASTERLIES AHEAD AND TO THE EAST OF ITS PATH. THE
LOW WILL THEN START TO PULL AWAY WESTWARD. A TROUGH OR ASSOCIATED
FRONTAL FEATURE WILL PUSH INTO THE SOUTHERN PANHANDLE SATURDAY
EVENING. 850 WINDS SHOULD PROVIDE FAIRLY GOOD JET SUPPORT FOR
STRONG SURFACE WINDS IN ZONE 27. BEST TIMES FOR THIS SATURDAY
AFTERNOON/EVENING AND AGAIN ON SUNDAY MORNING. AGAIN, THE
GRADIENT NOT GREAT FOR CLARENCE STRAIT, BUT DECIDED TO USE THE
70 PERCENT RULE OF 850 WINDS...AND THIS TRANSLATED AS GALE DOWN
TO THE SURFACE. RIGHT NOW LEFT OUT STRONG WINDS FOR ZONE 28.
THINK IT WILL BE A BETTER SET UP FOR STRONGER WINDS AT METLAKATLA
THAN KETCHIKAN. WINDS ACROSS THE NORTHERN PANHANDLE WILL BE AT
MOST NORTHERLY 20 KT.

 THE LOW ITSELF WILL SPREAD RAIN INTO THE SOUTHERN ZONES SATURDAY
AND THIS WILL ADVANCE NORTHWARD WITH THE TROUGH SATURDAY NIGHT.
THE BEST CHANCE FOR THE RAIN ARRIVING IN JUNEAU WILL BE SUNDAY
MORNING, BUT LEFT IT AS CHANCE IN THE WORDING FOR NOW. SATURDAY
SHOULD BE A FAIRLY NICE DAY IN THE NORTH. FOLKS SHOULD SEE SOME
SUNNY BREAKS THROUGH THE MOSTLY CLOUDY SKIES. HAINES/SKAGWAY WILL
BE EVEN SUNNIER. ANYTHING THAT FALLS WILL LIKELY BE LIGHT...AS
MIDLEVEL WINDS WILL BE MORE SOUTHEASTERLY THAN SOUTH OR
SOUTHWEST. THIS IS A MUCH DRIER DIRECTION OF RAIN FOR THE
NORTHERN PANHANDLE. THEN ONCE AGAIN...RAIN CHANCES WILL DIMINISH
SUNDAY AFTERNOON AS THE LOW PULLS THE RAIN BACK TOWARD THE GULF.

 LOOKING FURTHER OUT...MORE MODEL DIVERGENCE INCREASES NEXT
WEEK...BUT OVERALL GENERAL TROUGHINESS WITH PERIODS OF ONSHORE
FLOW SHOULD MEAN CHANCES OF RAIN AND MAINLY CLOUDY SKIES FOR THE
PERIOD. TEMPERATURES WILL GENERALLY BE FAIRLY SEASONABLE FOR THIS
TIME OF YEAR.

 MODEL OF CHOICE WAS ECMWF WITH SOME HELP FROM GEM REGARDING POP
ADVANCEMENT NORTHWARD.

.AJK WATCHES/WARNINGS/ADVISORIES...
PUBLIC...NONE.
MARINE...GALE WARNING FOR PKZ036-041>043.
         SMALL CRAFT ADVISORY FOR PKZ012-013-021-022-033>035-051-052.

&&

$$

PRB/JWA










000
FXAK67 PAJK 172220
AFDAJK

SOUTHEAST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE JUNEAU AK
220 PM AKDT THU APR 17 2014

.SHORT TERM...EARLY AFTERNOON SATELLITE IMAGERY SHOWS A MATURE
YET COMPACT LOW PRESSURE SYSTEM JUST OFF THE COAST OF PRINCE OF
WALES ISLAND JUST SOUTH OF CAPE DECISION. THIS LOW WILL CONTINUE
TO PUSH NORTH AND HUG ALONG THE COAST, AND WEAKEN. BY FRIDAY,
THIS AREA OF LOW PRESSURE WILL BECOME AN OPEN TROUGH. A RIDGE OF
HIGH PRESSURE WILL BUILD ACROSS THE PANHANDLE FROM THE SOUTH ON
FRIDAY.

 A RATHER MILD THURSDAY, AS HIGH TEMPERATURES IN THE AREA RISE TO
THE UPPER 40S TO THE LOW 50S. SOUTHERN AREAS ARE A BIT COOLER DUE
TO RAIN SHOWERS IN THE AREA. DRY CONDITIONS CONTINUE FOR THE
NORTHERN PANHANDLE , AS NORTHEASTERLY FLOW KEPT THE PRECIPITATION
FROM MOVING INTO THE AREA.

 AS THE LOW TRACKS NORTH, IT TIGHTENS THE NORTHERLY PRESSURE
GRADIENT ACROSS NORTHERN PANHANDLE. NORTHERLY WIND OF 10 TO
15 MPH CAN BE FOUND IN SKAGWAY, HAINES, GUSTAVUS, AND LYNN CANAL
THIS AFTERNOON. THE WEATHER FRONT IS SITUATED ALONG CENTRAL
PANHANDLE, AND WILL CONTINUE TO PUSH NORTH THIS EVENING. ONCE THE
WEATHER FRONT PUSHES THROUGH, WINDS WILL BECOME SOUTHERLY. WITH A
RIDGE OF HIGH PRESSURE BUILDING IN BEHIND FROM THE SOUTH, THAT
WILL GENERATE A STRONG PUSH OF SOUTHERLY WIND ACROSS THE
PANHANDLE. DO EXPECT THE STRONGER SOUTHERLY WINDS TO IMPACT
SOUTHERN PANHANDLE THROUGH THIS EVENING. THE AREA OF STRONGER
SOUTH WINDS WILL MOVE NORTH THROUGH TONIGHT INTO FRIDAY.

 FORECAST CONFIDENCE IS ABOVE AVERAGE. MOST NUMERICAL WEATHER
MODELS ARE SHOWING CONSENSUS ON THE WEAKENING LOW TONIGHT AND A
BUILDING RIDGE ON FRIDAY. UTILIZE A SUPERBLEND OF MODELS TO
UPDATE THE INHERITED FORECAST PACKAGE.

&&

.LONG TERM...MODELS ARE IN GENERAL AGREEMENT THROUGH LATE SUNDAY
FOR A WEAK UPPER LEVEL AND SURFACE RIDGE BUILDING ACROSS THE
EASTERN GULF AND SOUTHEAST ALASKA FROM THE SOUTH. THE RIDGE WILL
MOVE NORTHEASTWARD AWAY FROM THE AREA AS A LOW MOVES INTO THE
SOUTHEASTERN GULF BY SATURDAY MORNING. THE LOW WILL CONTINUE TO
ROTATE OVER THE GULF THROUGH THE WEEKEND. REFRESHED THE INHERITED
FORECAST PACKAGE WITH THE ECMWF THROUGH SUNDAY EVENING FOR ITS GOOD
CONSISTENCY. FOR EARLY NEXT WEEK...THE UPPER LOW AND ASSOCIATED
SURFACE FEATURE ACROSS THE ALASKA GULF WILL BEGIN WEAKENING AND
DRIFTING SOUTHEASTWARD. THEN A RIDGE WILL REBUILD OVER THE GULF
THROUGH THE MID WEEK. MODEL DIVERGENCE BECOMES MORE SIGNIFICANT
BETWEEN THE ERODING RIDGE AND A DEVELOPING LOW OVER THE WESTERN
ALASKA PENINSULA. BLENDED NEXT WEEK FORECAST PACKAGE WITH THE WPC
SOLUTIONS OF THE OPERATIONAL ECMWF THROUGH WEDNESDAY AND MIXED
WITH A LITTLE ECMWF ENSEMBLE FOR THURSDAY.

 AS THE RIDGE BUILDS FROM THE SOUTH...SOUTHERLY WINDS WILL
CONTINUE TO INCREASE FRIDAY NIGHT THEN BY EARLY SATURDAY
MORNING GALE FORCE WINDS WILL BEGIN AFFECTING THE SOUTHERN
OFFSHORE...OUTSIDE WATERS AND THE SOUTHERN INNER CHANNELS AS A LOW
MOVES INTO THE SOUTHERN GULF. STRONG WINDS HEADLINE MAY NEED FOR
PRINCE OF WALES ISLANDS. VERY ROUGH SEAS OF 20 TO 25 FEET ARE ALSO
EXPECTED OVER THE SOUTHERN OUTER WATERS. AS THE LOW CONTINUES
PROGRESSING...PRESSURE GRADIENT WILL SHIFT FOR A GRADUAL INCREASE
OF NORTHERLY WINDS ACROSS THE PANHANDLE LATE FRIDAY NIGHT INTO
SATURDAY...THEN CONTINUE THROUGH EARLY NEXT WEEK. FOR THE
REMAINING LONG TERM FORECAST PERIODS...EXPECT A BRIEF RIDGE BUILDS
ACROSS THE PANHANDLE ON MONDAY AHEAD OF THE NEXT DEVELOPING SYSTEM
ACROSS THE FAR WESTERN GULF. AS THE SYSTEM SLOWLY DRIFTS
EASTWARD...SEVERAL POORLY ORGANIZED WEAK LOWS WILL MOVE INTO THE
EASTERN GULF THROUGH THE WEEK. RELATIVELY HIGHER POPS WILL LIKELY
TO FOCUS OVER THE SOUTHERN PANHANDLE WEDNESDAY AND THURSDAY.

&&

.AJK WATCHES/WARNINGS/ADVISORIES...
PUBLIC...NONE.
MARINE...GALE WARNING FOR PKZ036.
         SMALL CRAFT ADVISORY FOR PKZ012-013-031-041-042.
         SMALL CRAFT ADVISORY DUE TO SEAS FOR PKZ043.

&&

$$

RCL/AHN










000
FXAK67 PAJK 171349
AFDAJK

SOUTHEAST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE JUNEAU AK
549 AM AKDT THU APR 17 2014

.SHORT TERM...990 MB LOW WEST OF DIXON ENTRANCE THIS MORNING
TRACKING NORTHWARD ALONG THE PANHANDLE COAST AS IT WEAKENS
REACHING CROSS SOUND THURSDAY EVENING. AS THE LOW WEAKENS TO AN
OPEN WAVE TROUGH IT WILL CONTINUE ITS NORTHERLY TRACK TOWARDS
YAKUTAT BAY THROUGH FRIDAY MORNING. A RIDGE OF HIGH PRESSURE WILL
BUILD OVER THE PANHANDLE THROUGH THIS TIME.

 RAIN IS CURRENTLY FALLING OVER THE SOUTHERN PANHANDLE AND WILL
MOVE NORTHWARD THROUGH THE DAY WITH THE ADVANCING LOW. PRECIP
WILL BE ON THE LIGHTER SIDE FOR THE CENTRAL AND NORTHERN
PANHANDLE AS WHILE THE LOW WEAKENS TO AN OPEN WAVE TROUGH.
TEMPERATURES WILL RISE INTO THE ID TO UPPER 40S TODAY, NOT AS
WARM AS WEDNESDAY DUE TO THE INCREASING CLOUD COVER. OVERNIGHT
LOWS DROPPING INTO THE MID TO UPPER 30S DUE TO THE LINGERING
CLOUD COVER. PRECIP WILL FALL MOSTLY AS RAIN WITH SOME SNOW MIXED
IN AT HIGHER ELEVATIONS ALONG THE KLONDIKE HIGHWAY.

 WINDS OVER THE SOUTHERN PANHANDLE NOT QUITE AS STRONG AS MODELS
HAD ORIGINALLY PREDICTED. THERE IS STILL THE SECONDARY WRAP WITH
850 MB WINDS IN THE 30 TO 40 KT RANGE THIS AFTERNOON WHICH WILL
INCREASE WINDS FOR THE SOUTHERN INNER CHANNELS. AS THE HIGH
PRESSURE RIDGE BUILDS IN NORTHERLY WINDS WILL WEAKEN THIS MORNING
THEN SHIFT TO THE SOUTH. THESE SOUTHERLY WINDS WILL INCREASE LATE
TONIGHT AS THE GRADIENT BETWEEN THE RIDGE AND LOW OVER THE YUKON
INCREASES.

 MODELS IS FAIR AGREEMENT WITH NAM/EC SHOWING A GOOD MATCH WITH
MSAS PRESSURE GRIDS. LIKED THE ECMWF INITIALIZATION WHEN
COMPARING 300 MB RH AND WATER VAPOR SATELLITE IMAGERY. A NAM/EC
BLEND WAS VERY CLOSE TO INHERITED GRIDS SO NOT MUCH CHANGE WITH
PRESSURE AND POP FIELDS. DID DROP DOWN WINDS THIS MORNING AS THE
GALES IN THE SOUTHERN AK GULF DID NOT MATERIALIZE. WHILE MODELS
WERE IN GOOD AGREEMENT AND INITIALIZED WELL WITH PRESS FIELDS
FORECAST CONFIDENCE IS ONLY AVERAGE AS MUCH OF THE EARLY MORNING
MODEL GUIDANCE STILL HAD TOO HIGH WINDS.

.LONG TERM...SURFACE RIDGE WILL BUILD QUICKLY FRIDAY MORNING
BEHIND THE FRONT PUSHING ACROSS THE PANHANDLE THUS BOOSTING
SOUTHERLY WINDS BRIEFLY BEFORE DIMINISHING IN THE AFTERNOON.
EXPECT SMALL CRAFTS IN STEPHENS PASSAGE AS WELL AS LYNN CANAL. BUT
GRADIENTS WILL BEGIN TO FLIP NORTHERLY AGAIN FRIDAY NIGHT IN
RESPONSE TO A DEVELOPING SYSTEM WELL SOUTH OF THE ALASKA PENINSULA
IN THE NORTH PACIFIC. THIS SYSTEM WILL DEEPEN AS IT ADVANCES INTO
THE OUTER GULF FRIDAY. EASTERLY AND SOUTHEASTERLY SOLID GALES WILL
SPREAD NORTHWARD AHEAD OF THE SYSTEM FRIDAY NIGHT INTO SATURDAY
OVER ZONE 310 AS WELL AS THE SOUTHERN OUTSIDE MARINE ZONES. REDUCED
THE WINDS FRIDAY NIGHT FOR CLARENCE STRAIT AS THE ORIENTATION
SHOULD BE SUCH THAT THE MAIN CHANNEL WINDS WILL NOT BE AS STRONG
AS NORTHEAST-ORIENTED PASSES. THIS WILL CHANGE SATURDAY AS THE
LOW MOVES NORTHWARD AND MIDLEVEL JET AT 850 MB ACCELERATES WINDS
TO 50 KT FROM THE SOUTHEAST. AS SUPPORTING LOW ALOFT BROADENS
SURFACE LOW WILL ALSO BEGIN FILLING AND GRADIENTS AND WIND WILL
DIMINISH SATURDAY NIGHT...EVEN BECOMING LIGHT IN SOME AREAS BY
MONDAY. EXPECT WIND GUSTS TO BE STRONG FOR PRINCE OF WALES ISLAND
FRIDAY NIGHT/SATURDAY.

POST-FRONTAL RIDGE WILL DESTABILIZE THE ATMOSPHERE ENOUGH FOR RAIN
TO FALL AS SHOWERS FRIDAY. THESE SHOWERS WILL DIMINISH THROUGH
FRIDAY NIGHT...AS MIDLEVEL WINDS BEGIN TO TURN MORE SOUTHEASTERLY
FROM A MORE MOIST SOUTHWESTERLY DIRECTION. FOR THE GALE-FORCE
SYSTEM MOVING IN FRIDAY NIGHT/SATURDAY, DID SHAVE OFF POPS FOR
NORTHERN PANHANDLE BECAUSE OF THIS. LEFT ISOLATED SHOWERS OVER
MUCH OF NORTHERN PANHANDLE FRIDAY NIGHT, BUT THIS IS NUDGING THE
FORECAST TO SOMETHING APPROACHING WHAT I REALLY THINK...IE, I
DON`T THINK IT WILL RAIN IN JUNEAU FRIDAY NIGHT. USUALLY STRONG
SYSTEMS ARE PRECEDED BY STRONGER RIDGING.

TEMPERATURES WILL BOUNCE BACK UP IN THE 50S FOR THE NORTHERN
PANHANDLE SATURDAY AS OFFSHORE FLOW DRIES THE REGION OUT. HOWEVER,
THE SOUTHERN PANHANDLE MAY ACTUALLY COOL AS THE SURFACE LOW WILL
SPREAD RAIN FROM DIXON ENTRANCE. CANNOT RULE OUT SOME SNOW MIXING
IN WITH THE SHOWERS AS THEY END FRIDAY NIGHT, BUT AGAIN, THINK
TEMPERATURES WILL COOL AS THE ATMOSPHERE DRIES OUT.

NEXT WEEK...LOOK FOR MAINLY CLOUDY SKIES WITH RAIN CHANCES OVER
MOST OF THE PANHANDLE...ASSOCIATED WITH POORLY RESOLVED LOWS
OVER THE GULF.

MODELS OF CHOICE WERE GFS/ECMWF IN THE MID-RANGE...WPC IN LONG-
RANGE. FORECAST CONFIDENCE GOOD OVERALL WITH GOOD MODEL AGREEMENT.

.AJK WATCHES/WARNINGS/ADVISORIES...
PUBLIC...NONE.
MARINE...SMALL CRAFT ADVISORY FOR PKZ012-036-041-042.
         SMALL CRAFT ADVISORY DUE TO SEAS FOR PKZ043.

&&

$$

PRB/JWA











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