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000
FXAK67 PAJK 261309
AFDAJK

SOUTHEAST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE JUNEAU AK
509 AM AKDT SAT JUL 26 2014

.SHORT TERM...WATER VAPOR IMAGERY SHOWS UPPER LOW CONTINUING TO
SPIN OVER THE GULF EARLY THIS MORNING. SENSIBLE WEATHER WILL BE
VERY SIMILAR TO FRI WITH RAIN PERSISTING THROUGH MUCH OF THE DAY.
BLENDED EC/NAM WITH INHERITED PACKAGE RESULTING IN A SLIGHT SHIFT
W OF THE SURFACE LOW OVER THE NORTHERN GULF.

 THE MAIN FORECAST CHALLENGE WILL AGAIN BE THE TIMING OF HEAVIER
RAINS AND STRENGTH OF WINDS OVER THE INNER CHANNELS. SATELLITE
IMAGERY AND SURFACE ANALYSIS SHOW ONE WAVE MOVING ACROSS THE
PANHANDLE AT THIS TIME WITH ANOTHER WAVE EVIDENT ON WV IMAGERY
ROUNDING THE BASE OF THE TROUGH OVER THE GULF. EXPECT MDT-HEAVY
RAINS TO CONTINUE PUSHING N-NW ACROSS THE PANHANDLE THIS MORNING
WITH RAINS EASING UNTIL THE NEXT SHORTWAVE INCREASES PRECIP OVER
THE SOUTHERN PANHANDLE LATE THIS MORNING INTO THE AFTERNOON.
MODELS IN VERY GOOD AGREEMENT WITH A THIRD DISTURBANCE ROTATING
AROUND THE PARENT TROUGH TONIGHT. RAIN WILL EASE AND INCREASE A
COUPLE OF TIMES THROUGH THE PERIOD AS EACH WAVE PASSES.

 WINDS ACROSS MOST OF THE PANHANDLE WILL CONTINUE TO BE MODERATE
TO STRONG SOUTHERLIES WITH THE TIGHTEST PRESSURE GRADIENT AGAIN
ACROSS THE SOUTHERN PANHANDLE AND ALONG THE OUTER COAST. WITH THE
SURFACE LOW EXPECTED TO BE SLIGHTLY FURTHER WEST...THE GRADIENT
WILL BE SLIGHTLY WEAKER TODAY SO KEPT NEAR GALES TODAY OVER
CLARENCE STRAIT WITH WITH ADVISORIES NORTH INTO SOUTHERN CHATHAM
AND CROSS SOUND.

 FORECAST CONFIDENCE IS VERY HIGH IN ANOTHER WET AND BREEZY DAY
ACROSS SOUTHEAST AK.

 .LONG TERM...BLOCKING PATTERN THAT IS KEEPING THE UPPER LEVEL
LOW OVER THE AK GULF WILL REMAIN IN PLACE THROUGH THE WEEK THEN
BEGIN TO BREAK DOWN BY NEST WEEKEND. MODELS ARE IN GOOD AGREEMENT
FOR THIS UPPER LEVEL SYNOPTIC PATTERN WITH THE LOW BETWEEN THE N
PACIFIC/BERING SEA AND CONUS HIGH PRESSURE RIDGES THROUGH FRIDAY
BUT THEN DIVERGE WITH THE TIMING OF THE RIDGES BREAKING DOWN. THE
CYCLONIC ROTATING SURFACE LOWS/SHORTWAVES OVER THE GULF WILL
CONTINUE TO KEEP THE SE PANHANDLE WITH WET WEATHER AND CLOUDY
SKIES WITH SOME BREAKS AS THE WAVES PULL OFF THE THE WEST.
LONGEST BREAKS OCCURRING TOWARD THE END OF THE WEEK BEFORE THE
BLOCK BREAKS DOWN. NEW MODEL RUNS ARE IN BETTER AGREEMENT THROUGH
84 HOURS WITH THE POSITION OF THESE FEATURES BUT NOT IN GREAT
AGREEMENT WITH THE RESULTING POP FIELDS. AT THIS TIME THE SUNDAY
SHORTWAVE LOOKS TO PULL WEST WITH THE NEXT WAVE MOVING IN ON
TUESDAY. EACH WAVE WILL BRING IN PRECIP AND INCREASING WINDS BUT
LOCATION OF THE LOW COULD KEEP THINGS FURTHER OFF SHORE.
INDICATIONS THAT THE NEXT LOW WILL BRING IN STRONGER WINDS WITH
COASTAL WATERS AND SOUTHERN INNER CHANNELS REACHING SMALL CRAFT
LEVELS, BUT FOR NOW KEEPING THE SOUTHERLY WINDS SPEEDS IN THE
20 KT RANGE. LITTLE CHANGE DONE TO TEMPERATURES WITH LIMITED
DIURNAL RANGE THROUGH THE WEEK DUE TO RAINFALL AND CLOUD COVER.
MOS GUIDANCE STILL SHOWING A LARGER DIURNAL SPREAD BUT WITH
EXPECTED CLOUD COVER THE WARMER TEMPS MAY BE OVER DONE.

 KEEPING A WATCH ON THE TRACK OF A FORMER TYPHOON AND IF IT WILL
BE PUSHED NORTH AND KEPT WELL WEST OF OUR AREA OR PASSES FAR
ENOUGH SOUTH TO BE ABLE TO TRACK EAST AND THEN GET CAUGHT UP IN
THE UPPER LEVEL LOW CIRCULATION OVER THE GULF BRINGING WIDE
SPREAD HEAVY PRECIPITATION OVER THE PANHANDLE. FOR NOW MODELS
LEANING TOWARD KEEPING THIS FEATURE TO THE NORTH AND WEST.

 STAYED WITH THE TREND OF USING ENSEMBLE BLEND WITH 00Z ECMWF/GFS
AND SOME NAM FOR PRESS AND WINDS THEN TRANSITION TO WPC FOR THE
EXTENDED FORECAST. WHILE THE POSITION OF THE LOW ON SUN WAS
FURTHER WEST OVERALL CHANGES TO THE FORECAST WERE MINOR. ALTHOUGH
THE MODELS ARE IN GOOD CONSENSUS FOR THE SYNOPTIC SCALE PATTERN
STILL ENOUGH VARIATION AT THE SURFACE FOR LESS CONFIDENCE IN THE
PRACTICAL FORECAST. AS MODELS USUALLY HAVE DIFFICULTY WITH TIMING
LARGE PATTERN CHANGES CONFIDENCE DROPS WITH THE TIMING OF THE
BLOCKING PATTERN BREAKDOWN.

&&

.AJK WATCHES/WARNINGS/ADVISORIES...
PUBLIC...NONE.
MARINE...SMALL CRAFT ADVISORY FOR PKZ022-033-035-036-041>043.


$$

BC/PRB







000
FXAK67 PAJK 261309
AFDAJK

SOUTHEAST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE JUNEAU AK
509 AM AKDT SAT JUL 26 2014

.SHORT TERM...WATER VAPOR IMAGERY SHOWS UPPER LOW CONTINUING TO
SPIN OVER THE GULF EARLY THIS MORNING. SENSIBLE WEATHER WILL BE
VERY SIMILAR TO FRI WITH RAIN PERSISTING THROUGH MUCH OF THE DAY.
BLENDED EC/NAM WITH INHERITED PACKAGE RESULTING IN A SLIGHT SHIFT
W OF THE SURFACE LOW OVER THE NORTHERN GULF.

 THE MAIN FORECAST CHALLENGE WILL AGAIN BE THE TIMING OF HEAVIER
RAINS AND STRENGTH OF WINDS OVER THE INNER CHANNELS. SATELLITE
IMAGERY AND SURFACE ANALYSIS SHOW ONE WAVE MOVING ACROSS THE
PANHANDLE AT THIS TIME WITH ANOTHER WAVE EVIDENT ON WV IMAGERY
ROUNDING THE BASE OF THE TROUGH OVER THE GULF. EXPECT MDT-HEAVY
RAINS TO CONTINUE PUSHING N-NW ACROSS THE PANHANDLE THIS MORNING
WITH RAINS EASING UNTIL THE NEXT SHORTWAVE INCREASES PRECIP OVER
THE SOUTHERN PANHANDLE LATE THIS MORNING INTO THE AFTERNOON.
MODELS IN VERY GOOD AGREEMENT WITH A THIRD DISTURBANCE ROTATING
AROUND THE PARENT TROUGH TONIGHT. RAIN WILL EASE AND INCREASE A
COUPLE OF TIMES THROUGH THE PERIOD AS EACH WAVE PASSES.

 WINDS ACROSS MOST OF THE PANHANDLE WILL CONTINUE TO BE MODERATE
TO STRONG SOUTHERLIES WITH THE TIGHTEST PRESSURE GRADIENT AGAIN
ACROSS THE SOUTHERN PANHANDLE AND ALONG THE OUTER COAST. WITH THE
SURFACE LOW EXPECTED TO BE SLIGHTLY FURTHER WEST...THE GRADIENT
WILL BE SLIGHTLY WEAKER TODAY SO KEPT NEAR GALES TODAY OVER
CLARENCE STRAIT WITH WITH ADVISORIES NORTH INTO SOUTHERN CHATHAM
AND CROSS SOUND.

 FORECAST CONFIDENCE IS VERY HIGH IN ANOTHER WET AND BREEZY DAY
ACROSS SOUTHEAST AK.

 .LONG TERM...BLOCKING PATTERN THAT IS KEEPING THE UPPER LEVEL
LOW OVER THE AK GULF WILL REMAIN IN PLACE THROUGH THE WEEK THEN
BEGIN TO BREAK DOWN BY NEST WEEKEND. MODELS ARE IN GOOD AGREEMENT
FOR THIS UPPER LEVEL SYNOPTIC PATTERN WITH THE LOW BETWEEN THE N
PACIFIC/BERING SEA AND CONUS HIGH PRESSURE RIDGES THROUGH FRIDAY
BUT THEN DIVERGE WITH THE TIMING OF THE RIDGES BREAKING DOWN. THE
CYCLONIC ROTATING SURFACE LOWS/SHORTWAVES OVER THE GULF WILL
CONTINUE TO KEEP THE SE PANHANDLE WITH WET WEATHER AND CLOUDY
SKIES WITH SOME BREAKS AS THE WAVES PULL OFF THE THE WEST.
LONGEST BREAKS OCCURRING TOWARD THE END OF THE WEEK BEFORE THE
BLOCK BREAKS DOWN. NEW MODEL RUNS ARE IN BETTER AGREEMENT THROUGH
84 HOURS WITH THE POSITION OF THESE FEATURES BUT NOT IN GREAT
AGREEMENT WITH THE RESULTING POP FIELDS. AT THIS TIME THE SUNDAY
SHORTWAVE LOOKS TO PULL WEST WITH THE NEXT WAVE MOVING IN ON
TUESDAY. EACH WAVE WILL BRING IN PRECIP AND INCREASING WINDS BUT
LOCATION OF THE LOW COULD KEEP THINGS FURTHER OFF SHORE.
INDICATIONS THAT THE NEXT LOW WILL BRING IN STRONGER WINDS WITH
COASTAL WATERS AND SOUTHERN INNER CHANNELS REACHING SMALL CRAFT
LEVELS, BUT FOR NOW KEEPING THE SOUTHERLY WINDS SPEEDS IN THE
20 KT RANGE. LITTLE CHANGE DONE TO TEMPERATURES WITH LIMITED
DIURNAL RANGE THROUGH THE WEEK DUE TO RAINFALL AND CLOUD COVER.
MOS GUIDANCE STILL SHOWING A LARGER DIURNAL SPREAD BUT WITH
EXPECTED CLOUD COVER THE WARMER TEMPS MAY BE OVER DONE.

 KEEPING A WATCH ON THE TRACK OF A FORMER TYPHOON AND IF IT WILL
BE PUSHED NORTH AND KEPT WELL WEST OF OUR AREA OR PASSES FAR
ENOUGH SOUTH TO BE ABLE TO TRACK EAST AND THEN GET CAUGHT UP IN
THE UPPER LEVEL LOW CIRCULATION OVER THE GULF BRINGING WIDE
SPREAD HEAVY PRECIPITATION OVER THE PANHANDLE. FOR NOW MODELS
LEANING TOWARD KEEPING THIS FEATURE TO THE NORTH AND WEST.

 STAYED WITH THE TREND OF USING ENSEMBLE BLEND WITH 00Z ECMWF/GFS
AND SOME NAM FOR PRESS AND WINDS THEN TRANSITION TO WPC FOR THE
EXTENDED FORECAST. WHILE THE POSITION OF THE LOW ON SUN WAS
FURTHER WEST OVERALL CHANGES TO THE FORECAST WERE MINOR. ALTHOUGH
THE MODELS ARE IN GOOD CONSENSUS FOR THE SYNOPTIC SCALE PATTERN
STILL ENOUGH VARIATION AT THE SURFACE FOR LESS CONFIDENCE IN THE
PRACTICAL FORECAST. AS MODELS USUALLY HAVE DIFFICULTY WITH TIMING
LARGE PATTERN CHANGES CONFIDENCE DROPS WITH THE TIMING OF THE
BLOCKING PATTERN BREAKDOWN.

&&

.AJK WATCHES/WARNINGS/ADVISORIES...
PUBLIC...NONE.
MARINE...SMALL CRAFT ADVISORY FOR PKZ022-033-035-036-041>043.


$$

BC/PRB








000
FXAK67 PAJK 252347
AFDAJK

SOUTHEAST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE JUNEAU AK
347 PM AKDT FRI JUL 25 2014

.SHORT TERM...THIS SHIFT RELIED LARGELY ON CONCEPTS AND PRIOR
EXPERIENCES...WITH SOME HELP FROM HOW WINDS RESPONDED TO THE
FRONTAL PASSAGE MOVING NORTH ACROSS THE SOUTHERN HALF OF THE
PANHANDLE.

 LET US BEGIN WITH WHAT WE KNOW. RAIN. WHETHER IT FALLS AT TIMES
IN BURSTS LIKE SHOWERS OWING TO SOME VERTICAL
ACCELERATIONS/INSTABILITY IN LAYERS ALOFT OR WHETHER IT FALLS
MORE STEADILY AT TIMES...AFTER ATTEMPTING TO ANALYZE SUBTLE
ATMOSPHERIC REGIMES AND FAILING, DECIDED TO DESCRIBE THINGS HOW
IT IS...RAIN FALLING IN PERIODS. DID BRIEFLY COORDINATE WITH RFC
BASED ON RAINFALL TOTALS, AND SEE NO THREATS OF ANY RISES EVEN TO
ACTION IN THE SHORT-TERM. BUT IT WILL BE WET.

 THE LARGEST TIME SPENT WAS FOR WINDS. TRIED TO USE THE 850 NAM
WINDS FOR TIMING ISSUES IN REGARDS TO JETS THAT MAY SUPPORT
SURFACE LEVEL BURSTS. ARRIVED AT MORE SMALL CRAFT ESPECIALLY OVER
THE CENTRAL PANHANDLE...AS SOUTHERN PANHANDLE WAS ALREADY
COVERED. STIKINE VESSEL CALLED OUR ATTENTION EARLY ON THAT WINDS
WERE GOING TO BLOW STRONGER THAN FORECAST TODAY AS CLARENCE
STRAIT WAS ALREADY BLOWING SUSTAINED AT 30 KT. A QUICK MORNING
UPDATE TO BOOST WINDS FOR THE DAY COUPLED WITH GUSTS EXCEEDING
50 KT AT LINCOLN ROCK LEAD US TO POST A GALE WARNING FOR THIS
EVENING. NAM INTERESTINGLY ADVERTISING ANOTHER 850 MB JET MOVING
ACROSS SATURDAY AFTERNOON. WHILE BOOSTED CLARENCE TO 30 HERE...WE
MAY NEED TO SERIOUSLY THINK OF THE POSSIBILITY OF ANOTHER GALE.
STEPHENS PASSAGE IS ANOTHER AREA OF ANTICIPATION. IN THE END DID
NOT GO SMALL CRAFT BUT INCLUDED SOME GUSTY LANGUAGE FOR THIS
EVENING AS THE FRONT PROBABLY STARTS TO GO ALOFT SOMEWHERE
BETWEEN FIVE FINGERS AND JUNEAU.

 COOLED TEMPS JUST A TAD AGAIN TO LOWER INTO THE 50S OVER THE FAR
NORTH...FOR RAIN COOLED AIR. LOW 50S LOOKED GOOD FOR LOWS.

 USED NAM AND A LITTLE ECMWF FOR UPDATES. FORECAST CONFIDENCE
EXCELLENT ON PERIODS OF RAIN...SKETCHY ON WIND GUSTS REGARDING
TIMING/SPATIAL SPREAD.

 .LONG TERM...VERY GOOD MODEL AGREEMENT IN THE UPPER LEVELS WITH
A LOW OVER THE GULF THAT REMAINS STATIONARY AND WEDGED IN BETWEEN
UPPER LEVEL RIDGES TO THE WEST AND EAST. ECMWF BREAKS DOWN THIS
PATTERN TOWARDS THE END OF THE MODEL RUN AND ALLOWING A MORE
PROGRESSIVE PATTERN TO DEVELOP. GFS NOT SHOWING THIS YET, BUT
THERE ARE SEVERAL DAYS YET TO WATCH FOR THIS POSSIBLE DEVELOPMENT.
UPDATED MONDAY MORNING THROUGH WEDNESDAY MORNING WITH A
NAM/GFS/ECMWF BLEND TO BETTER DEPICT THE LOCATION OF THE NEXT WEAK
LOW TO DEVELOP AND ROTATE CYCLONICALLY AROUND THE GULF. CYCLONIC OFFSHORE
WINDS 20 KTS OR LESS THROUGHOUT THE ENTIRE EXTENDED RANGE FORECAST
PERIOD. HAVE A DIMINISHING SOUTHEASTERLY SMALL CRAFT IN CLARENCE
STRAIT AT THE VERY BEGINNING OF THE EXTENDED RANGE FORECAST PERIOD
SATURDAY EVENING.

CURRENTLY THERE ARE PERIODS OF MODERATE TO HEAVY PRECIPITATION IN
THE VARIOUS MODELS THAT OCCUR OVER THE COURSE OF THE NEXT WEEK,
BUT NO STORM TOTALS THAT ARE EXPECTED TO CAUSE ANY RIVERS
TO GET INTO FLOOD STAGE. ONE THING TO WATCH OUT FOR WILL BE
WHETHER A FORMER TYPHOON GETS BLOCKED AND SHUNTED TO THE NORTH
WELL WEST OF OUR AREA OR PASSES FAR ENOUGH SOUTH TO BE ABLE TO
TRACK EAST AND THEN GET CAUGHT UP IN THE UPPER LEVEL LOW
CIRCULATION OVER THE GULF. WERE THAT TO HAPPEN, THERE COULD BE
WIDE SPREAD HEAVY PRECIPITATION OVER THE PANHANDLE. WILL KEEP A
CLOSE WATCH ON THIS. UPDATES TO POP MADE FROM SUNDAY NIGHT
THROUGH MONDAY NIGHT USING A BLEND OF ECMWF, GFS, AND GEM. QPF
PRIMARILY FROM RFC WITH SOME ECMWF.

 TEMPERATURE GUIDANCE CONTINUES TO FORECAST TOO MUCH DIURNAL
VARIATION - TOO WARM DURING THE DAY, AND TOO COOL AT NIGHT -
BASED ON EXPECTED CLOUD COVER AND LOW LEVEL AIRMASS TEMPERATURES.
EXISTING VALUES LOOKED GOOD, SO DID NOT MAKE AND CHANGES TO TEMPS.

FORECAST CONFIDENCE IN CONTINUED WET WEATHER BASED ON A STATIONARY
UPPER LOW OVER THE GULF IS ABOVE AVERAGE. CONFIDENCE IN TIMING OF
BANDS OF HEAVIER PRECIPITATION BELOW AVERAGE DUE TO MODEL
DIFFERENCES IN TRACKING WEAK TROUGHS OVER THE FORECAST AREA.

 &&

.AJK WATCHES/WARNINGS/ADVISORIES...
PUBLIC...NONE.
MARINE...GALE WARNING FOR PKZ036.
         SMALL CRAFT ADVISORY FOR PKZ022-032>035-041>043.


$$

JWA/FRITSCH








000
FXAK67 PAJK 252347
AFDAJK

SOUTHEAST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE JUNEAU AK
347 PM AKDT FRI JUL 25 2014

.SHORT TERM...THIS SHIFT RELIED LARGELY ON CONCEPTS AND PRIOR
EXPERIENCES...WITH SOME HELP FROM HOW WINDS RESPONDED TO THE
FRONTAL PASSAGE MOVING NORTH ACROSS THE SOUTHERN HALF OF THE
PANHANDLE.

 LET US BEGIN WITH WHAT WE KNOW. RAIN. WHETHER IT FALLS AT TIMES
IN BURSTS LIKE SHOWERS OWING TO SOME VERTICAL
ACCELERATIONS/INSTABILITY IN LAYERS ALOFT OR WHETHER IT FALLS
MORE STEADILY AT TIMES...AFTER ATTEMPTING TO ANALYZE SUBTLE
ATMOSPHERIC REGIMES AND FAILING, DECIDED TO DESCRIBE THINGS HOW
IT IS...RAIN FALLING IN PERIODS. DID BRIEFLY COORDINATE WITH RFC
BASED ON RAINFALL TOTALS, AND SEE NO THREATS OF ANY RISES EVEN TO
ACTION IN THE SHORT-TERM. BUT IT WILL BE WET.

 THE LARGEST TIME SPENT WAS FOR WINDS. TRIED TO USE THE 850 NAM
WINDS FOR TIMING ISSUES IN REGARDS TO JETS THAT MAY SUPPORT
SURFACE LEVEL BURSTS. ARRIVED AT MORE SMALL CRAFT ESPECIALLY OVER
THE CENTRAL PANHANDLE...AS SOUTHERN PANHANDLE WAS ALREADY
COVERED. STIKINE VESSEL CALLED OUR ATTENTION EARLY ON THAT WINDS
WERE GOING TO BLOW STRONGER THAN FORECAST TODAY AS CLARENCE
STRAIT WAS ALREADY BLOWING SUSTAINED AT 30 KT. A QUICK MORNING
UPDATE TO BOOST WINDS FOR THE DAY COUPLED WITH GUSTS EXCEEDING
50 KT AT LINCOLN ROCK LEAD US TO POST A GALE WARNING FOR THIS
EVENING. NAM INTERESTINGLY ADVERTISING ANOTHER 850 MB JET MOVING
ACROSS SATURDAY AFTERNOON. WHILE BOOSTED CLARENCE TO 30 HERE...WE
MAY NEED TO SERIOUSLY THINK OF THE POSSIBILITY OF ANOTHER GALE.
STEPHENS PASSAGE IS ANOTHER AREA OF ANTICIPATION. IN THE END DID
NOT GO SMALL CRAFT BUT INCLUDED SOME GUSTY LANGUAGE FOR THIS
EVENING AS THE FRONT PROBABLY STARTS TO GO ALOFT SOMEWHERE
BETWEEN FIVE FINGERS AND JUNEAU.

 COOLED TEMPS JUST A TAD AGAIN TO LOWER INTO THE 50S OVER THE FAR
NORTH...FOR RAIN COOLED AIR. LOW 50S LOOKED GOOD FOR LOWS.

 USED NAM AND A LITTLE ECMWF FOR UPDATES. FORECAST CONFIDENCE
EXCELLENT ON PERIODS OF RAIN...SKETCHY ON WIND GUSTS REGARDING
TIMING/SPATIAL SPREAD.

 .LONG TERM...VERY GOOD MODEL AGREEMENT IN THE UPPER LEVELS WITH
A LOW OVER THE GULF THAT REMAINS STATIONARY AND WEDGED IN BETWEEN
UPPER LEVEL RIDGES TO THE WEST AND EAST. ECMWF BREAKS DOWN THIS
PATTERN TOWARDS THE END OF THE MODEL RUN AND ALLOWING A MORE
PROGRESSIVE PATTERN TO DEVELOP. GFS NOT SHOWING THIS YET, BUT
THERE ARE SEVERAL DAYS YET TO WATCH FOR THIS POSSIBLE DEVELOPMENT.
UPDATED MONDAY MORNING THROUGH WEDNESDAY MORNING WITH A
NAM/GFS/ECMWF BLEND TO BETTER DEPICT THE LOCATION OF THE NEXT WEAK
LOW TO DEVELOP AND ROTATE CYCLONICALLY AROUND THE GULF. CYCLONIC OFFSHORE
WINDS 20 KTS OR LESS THROUGHOUT THE ENTIRE EXTENDED RANGE FORECAST
PERIOD. HAVE A DIMINISHING SOUTHEASTERLY SMALL CRAFT IN CLARENCE
STRAIT AT THE VERY BEGINNING OF THE EXTENDED RANGE FORECAST PERIOD
SATURDAY EVENING.

CURRENTLY THERE ARE PERIODS OF MODERATE TO HEAVY PRECIPITATION IN
THE VARIOUS MODELS THAT OCCUR OVER THE COURSE OF THE NEXT WEEK,
BUT NO STORM TOTALS THAT ARE EXPECTED TO CAUSE ANY RIVERS
TO GET INTO FLOOD STAGE. ONE THING TO WATCH OUT FOR WILL BE
WHETHER A FORMER TYPHOON GETS BLOCKED AND SHUNTED TO THE NORTH
WELL WEST OF OUR AREA OR PASSES FAR ENOUGH SOUTH TO BE ABLE TO
TRACK EAST AND THEN GET CAUGHT UP IN THE UPPER LEVEL LOW
CIRCULATION OVER THE GULF. WERE THAT TO HAPPEN, THERE COULD BE
WIDE SPREAD HEAVY PRECIPITATION OVER THE PANHANDLE. WILL KEEP A
CLOSE WATCH ON THIS. UPDATES TO POP MADE FROM SUNDAY NIGHT
THROUGH MONDAY NIGHT USING A BLEND OF ECMWF, GFS, AND GEM. QPF
PRIMARILY FROM RFC WITH SOME ECMWF.

 TEMPERATURE GUIDANCE CONTINUES TO FORECAST TOO MUCH DIURNAL
VARIATION - TOO WARM DURING THE DAY, AND TOO COOL AT NIGHT -
BASED ON EXPECTED CLOUD COVER AND LOW LEVEL AIRMASS TEMPERATURES.
EXISTING VALUES LOOKED GOOD, SO DID NOT MAKE AND CHANGES TO TEMPS.

FORECAST CONFIDENCE IN CONTINUED WET WEATHER BASED ON A STATIONARY
UPPER LOW OVER THE GULF IS ABOVE AVERAGE. CONFIDENCE IN TIMING OF
BANDS OF HEAVIER PRECIPITATION BELOW AVERAGE DUE TO MODEL
DIFFERENCES IN TRACKING WEAK TROUGHS OVER THE FORECAST AREA.

 &&

.AJK WATCHES/WARNINGS/ADVISORIES...
PUBLIC...NONE.
MARINE...GALE WARNING FOR PKZ036.
         SMALL CRAFT ADVISORY FOR PKZ022-032>035-041>043.


$$

JWA/FRITSCH







000
FXAK67 PAJK 251248
AFDAJK

SOUTHEAST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE JUNEAU AK
448 AM AKDT FRI JUL 25 2014

.SHORT TERM...WATER VAPOR IMAGERY SHOWS AN UPPER LOW CONTINUING
TO SPIN OVER THE NE GULF WITH A STRONG SHORTWAVE ROTATING AROUND
THE BASE OF THE TROUGH EARLY THIS MORNING. THIS LOW WILL DRIFT
SLIGHTLY E AS THE SHORTWAVE EJECTS OUT THE BASE. THIS WAVE WILL
BRING STEADIER PRECIP TO THE REGION TODAY WITH ANOTHER...WEAKER
WAVE PROGGED TO ROTATE AROUND THE LOW THIS EVENING. THIS QUASI-
STATIONARY UPPER LOW WILL DRIFT BACK W AS THE FIRST WAVE
EXITS...THEN SLIDE SLIGHTLY E AS THE SECOND SHORTWAVE ROUNDS THE
BASE OF THE TROUGH. THIS MEANS THAT SHOWERS WILL TRANSITION TO
STRATIFORM PRECIP ACROSS THE CENTRAL AND SOUTHERN PANHANDLE THIS
MORNING...THEN BACK TO SHOWERS THIS AFTERNOON/EVENING BEFORE
BECOMING STRATIFORM AGAIN OVERNIGHT. RAINFALL AMOUNTS WILL
GENERALLY BE 1/4 TO 1/2 INCH TODAY WITH LOCALLY HIGHER AMOUNTS
ALONG THE OUTER COAST. 00Z MODELS CAME IN WITH MORE PRECIP
TONIGHT AS THE SECOND WAVE TAPS INTO SOME SUBTROPICAL MOISTURE
WITH OVERNIGHT RAINFALL AMOUNTS EXPECTED TO RANGE FROM
.5-.75 INCHES WITH LOCALIZED AMOUNTS OVER AN INCH ALONG SOUTHERN
BARANOF ISLAND.

 THE OTHER CONCERN DURING THIS SHORT TERM PERIOD WILL BE WINDS. A
BRIEF PERIOD OF ADVISORY LEVEL SOUTHERLIES OCCURRED IN NORTHERN
LYNN OVERNIGHT...AND WILL EASE THIS MORNING. WINDS ACROSS THE
SOUTHERN CHANNELS AND ALONG THE COASTAL WATERS WILL INCREASE
TODAY AS THE PRES GRADIENT TIGHTENS BETWEEN THE SFC LOW AND SFC
RIDGE OVER BRITISH COLUMBIA. ADVISORY LEVEL WINDS WILL DEVELOP
ALONG THE OUTER COAST S OF CAPE FAIRWEATHER AND ACROSS SUMNER AND
CLARENCE STRAITS THIS MORNING.

 .LONG TERM...BLOCKING PATTERN EXTENDING FROM KAMCHATKA PENINSULA
TO THE EASTERN CONUS WILL KEEP THE UPPER LEVEL LOW CURRENTLY OVER
THE AK GULF IN PLACE THROUGH THE EXTENDED FORECAST. MODELS ARE IN
GOOD AGREEMENT WITH RESPECT TO THE SYNOPTIC SCALE FEATURES WITH
THE GULF LOW LOCKED BETWEEN A RIDGE EXTENDING FROM THE NORTH
PACIFIC INTO THE BERING SEA AND A SECOND RIDGE EXTENDING FROM THE
WESTERN CONUS INTO NORTHWESTERN CANADA. WHERE THE MODELS DIVERGE
IS THE DETAILS OF THE SURFACE WAVES ROTATING AROUND THE GULF.
THESE SYSTEMS WILL KEEP WET WEATHER OVER THE PANHANDLE BUT BREAKS
WILL DEVELOP AS THE WAVES/VORT MAXES MOVE IN AND OUT, BUT THERE
IS SOME MODEL SPREAD ON THE EXACT TIMING OF THESE SYSTEMS. KEPT
WITH AN ENSEMBLE APPROACH EMPLOYED BY PREVIOUS SHIFTS WITH NEW
MODEL RUNS WHICH RESULTED IN LITTLE TO NO CHANGE.

 FOR INSIDE CHANNEL WINDS KEPT WITH THE SOUTHERLY WINDS FOLLOWING
THE GEOSTROPHIC FLOW AROUND THE LOW INSTEAD OF THE WEAK NORTHERLY
WINDS FROM THE PRESSURE GRADIENT. DO EXPECT SOME DIURNAL SHIFTS
FROM SOUTH TO NORTH AS THE LOW CENTER SHIFTS. WITH THE RAINFALL
AND CLOUD COVER THROUGH THE WEEK TEMPERATURE RANGES WILL BE SMALL
WITH HIGH IN THE UPPER 50S TO LOW 60S AND LOWS IN THE LOW TO MID
50S. TOWARDS MID WEEK MAY SEE WARMER DAY TIME HIGHS AS A BREAK IN
THE RAIN AND CLOUD COVER IS EXPECTED. MOS GUIDANCE STILL HAS A
WARM BIAS FOR DAY TIME TEMPS, ESPECIALLY THE MOST RECENT GFS.
FORECAST CONFIDENCE IS ABOVE AVERAGE FOR LARGE SCALE FEATURES
WITH LOWER CONFIDENCE ON TIMING OF THE SURFACE FEATURES.


&&

.AJK WATCHES/WARNINGS/ADVISORIES...
PUBLIC...NONE.
MARINE...SMALL CRAFT ADVISORY FOR PKZ012-035-036-041-042.
         SMALL CRAFT ADVISORY DUE TO SEAS FOR PKZ043.


$$

BC/PRB








000
FXAK67 PAJK 251248
AFDAJK

SOUTHEAST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE JUNEAU AK
448 AM AKDT FRI JUL 25 2014

.SHORT TERM...WATER VAPOR IMAGERY SHOWS AN UPPER LOW CONTINUING
TO SPIN OVER THE NE GULF WITH A STRONG SHORTWAVE ROTATING AROUND
THE BASE OF THE TROUGH EARLY THIS MORNING. THIS LOW WILL DRIFT
SLIGHTLY E AS THE SHORTWAVE EJECTS OUT THE BASE. THIS WAVE WILL
BRING STEADIER PRECIP TO THE REGION TODAY WITH ANOTHER...WEAKER
WAVE PROGGED TO ROTATE AROUND THE LOW THIS EVENING. THIS QUASI-
STATIONARY UPPER LOW WILL DRIFT BACK W AS THE FIRST WAVE
EXITS...THEN SLIDE SLIGHTLY E AS THE SECOND SHORTWAVE ROUNDS THE
BASE OF THE TROUGH. THIS MEANS THAT SHOWERS WILL TRANSITION TO
STRATIFORM PRECIP ACROSS THE CENTRAL AND SOUTHERN PANHANDLE THIS
MORNING...THEN BACK TO SHOWERS THIS AFTERNOON/EVENING BEFORE
BECOMING STRATIFORM AGAIN OVERNIGHT. RAINFALL AMOUNTS WILL
GENERALLY BE 1/4 TO 1/2 INCH TODAY WITH LOCALLY HIGHER AMOUNTS
ALONG THE OUTER COAST. 00Z MODELS CAME IN WITH MORE PRECIP
TONIGHT AS THE SECOND WAVE TAPS INTO SOME SUBTROPICAL MOISTURE
WITH OVERNIGHT RAINFALL AMOUNTS EXPECTED TO RANGE FROM
.5-.75 INCHES WITH LOCALIZED AMOUNTS OVER AN INCH ALONG SOUTHERN
BARANOF ISLAND.

 THE OTHER CONCERN DURING THIS SHORT TERM PERIOD WILL BE WINDS. A
BRIEF PERIOD OF ADVISORY LEVEL SOUTHERLIES OCCURRED IN NORTHERN
LYNN OVERNIGHT...AND WILL EASE THIS MORNING. WINDS ACROSS THE
SOUTHERN CHANNELS AND ALONG THE COASTAL WATERS WILL INCREASE
TODAY AS THE PRES GRADIENT TIGHTENS BETWEEN THE SFC LOW AND SFC
RIDGE OVER BRITISH COLUMBIA. ADVISORY LEVEL WINDS WILL DEVELOP
ALONG THE OUTER COAST S OF CAPE FAIRWEATHER AND ACROSS SUMNER AND
CLARENCE STRAITS THIS MORNING.

 .LONG TERM...BLOCKING PATTERN EXTENDING FROM KAMCHATKA PENINSULA
TO THE EASTERN CONUS WILL KEEP THE UPPER LEVEL LOW CURRENTLY OVER
THE AK GULF IN PLACE THROUGH THE EXTENDED FORECAST. MODELS ARE IN
GOOD AGREEMENT WITH RESPECT TO THE SYNOPTIC SCALE FEATURES WITH
THE GULF LOW LOCKED BETWEEN A RIDGE EXTENDING FROM THE NORTH
PACIFIC INTO THE BERING SEA AND A SECOND RIDGE EXTENDING FROM THE
WESTERN CONUS INTO NORTHWESTERN CANADA. WHERE THE MODELS DIVERGE
IS THE DETAILS OF THE SURFACE WAVES ROTATING AROUND THE GULF.
THESE SYSTEMS WILL KEEP WET WEATHER OVER THE PANHANDLE BUT BREAKS
WILL DEVELOP AS THE WAVES/VORT MAXES MOVE IN AND OUT, BUT THERE
IS SOME MODEL SPREAD ON THE EXACT TIMING OF THESE SYSTEMS. KEPT
WITH AN ENSEMBLE APPROACH EMPLOYED BY PREVIOUS SHIFTS WITH NEW
MODEL RUNS WHICH RESULTED IN LITTLE TO NO CHANGE.

 FOR INSIDE CHANNEL WINDS KEPT WITH THE SOUTHERLY WINDS FOLLOWING
THE GEOSTROPHIC FLOW AROUND THE LOW INSTEAD OF THE WEAK NORTHERLY
WINDS FROM THE PRESSURE GRADIENT. DO EXPECT SOME DIURNAL SHIFTS
FROM SOUTH TO NORTH AS THE LOW CENTER SHIFTS. WITH THE RAINFALL
AND CLOUD COVER THROUGH THE WEEK TEMPERATURE RANGES WILL BE SMALL
WITH HIGH IN THE UPPER 50S TO LOW 60S AND LOWS IN THE LOW TO MID
50S. TOWARDS MID WEEK MAY SEE WARMER DAY TIME HIGHS AS A BREAK IN
THE RAIN AND CLOUD COVER IS EXPECTED. MOS GUIDANCE STILL HAS A
WARM BIAS FOR DAY TIME TEMPS, ESPECIALLY THE MOST RECENT GFS.
FORECAST CONFIDENCE IS ABOVE AVERAGE FOR LARGE SCALE FEATURES
WITH LOWER CONFIDENCE ON TIMING OF THE SURFACE FEATURES.


&&

.AJK WATCHES/WARNINGS/ADVISORIES...
PUBLIC...NONE.
MARINE...SMALL CRAFT ADVISORY FOR PKZ012-035-036-041-042.
         SMALL CRAFT ADVISORY DUE TO SEAS FOR PKZ043.


$$

BC/PRB







000
FXAK67 PAJK 242346
AFDAJK

SOUTHEAST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE JUNEAU AK
346 PM AKDT THU JUL 24 2014

.SHORT TERM...A SOMEWHAT AIMLESS LONGWAVE CUT-OFF LOW OVER THE
GULF OF ALASKA THAT WAS RESPONSIBLE FOR SOME FRONTAL RAINS THIS
MORNING AND SOME SHOWERS THIS AFTERNOON OVER THE PANHANDLE IS
PRIMED FOR SOME EXCITEMENT TONIGHT AS A SHORTWAVE ENERGY BURSTS
SOUTH ACROSS THE KATMAI. THIS ENERGY WILL DEEPEN THE
TROUGH...FARTHER ENOUGH INTO THE NORTH PACIFIC TO TAP SOME
SUBTROPICAL MOISTURE. THIS WILL BEGIN ROUNDING THE BEND NORTHWARD
INTO THE PANHANDLE STARTING FRIDAY AND CONTINUE INTO THE WEEKEND.
THE SHORTWAVE WILL DEVELOP A SURFACE LOW WEST OF HAIDA GWAII LATE
THURSDAY NIGHT THAT WILL DRIVE A FRONT INTO THE SOUTHERN
PANHANDLE INTO FRIDAY.

FIRST PRECIPITATION...RAIN THAT HAS FALLEN OVER THE AREA HAS BEEN
SPOTTY AND SOMEWHAT INTENSE IN NATURE. I SHOULD ADD THAT THE
ECMWF`S TREATMENT FOR YAKUTAT AS WET TURNED OUT TO BE MORE CORRECT
THAN THE MUCH DRIER GFS AND NAM. THUS THE CONVECTION CALLED FOR
TODAY WORKED OUT FAIRLY WELL. THIS COLD POOL ASSOCIATED WITH THE
LOW OVER THE GULF WILL SUPPORT SHOWERS THROUGH TONIGHT AND WILL
ONLY TRANSITION INTO MORE STEADY RAINS BEGINNING FRIDAY MORNING
FOR THE SOUTHERN PANHANDLE BEFORE EXTENDING AS FAR NORTH AS LYNN
CANAL BY THE AFTERNOON. NAM SOUNDINGS SUGGEST THAT AREAS CLOSEST
TO THE CORE OF THE UPPER LOW MAY STAY A LITTLE MORE UNSTABLE, WITH
A SOUTHERLY 850 JET SPREADING NORTHWARD, IT WAS HARD TO TURN
AGAINST THE CONCEPTUAL PARADIGM OF PRE-FRONTAL STRATIFORM...SO
JUST PAINTED EVERYTHING AS RAIN FOR FRIDAY AFTERNOON SOUTHWEST OF
YAKUTAT.

WINDS...NO BIG WORRIES EXCEPT FOR THE STRENGTH OF THE SOUTHERLIES
RISING IN THE SOUTH FRIDAY MORNING. SMALL CRAFTS FOR SOUTHERN
PASSAGES LOOKED GOOD. DID CONTINUE THE TREND OF BOOSTING WINDS FOR
BLOWHOLES LIKE HYDABURG AND ADDED SOME GUSTY LANGUAGE FOR SOUTHERN
BARANOF. PARTNER ON OUR DESK TODAY NOTICED THE WRF HAD CORRECTLY PREDICTED
THE GUSTINESS IN SITKA TODAY. WRF...WE MISSED YOU DURING YOUR
ABSENCE. ALWAYS A LITTLE SKETCHY ON STRENGTH AND EVEN DIRECTION OF
WINDS WHERE SURFACE GRADIENT RUNS COUNTER TO WINDS ALOFT. KIND OF
TOOK AN AVERAGE OF STRONG SOUTHERLIES AND WEAK NORTHERLIES TO
ARRIVE AT WEAK SOUTHERLIES FOR STEPHENS PASSAGE/NORTHERN CHATHAM.

NO BIG HYDRO ISSUES EXPECTED IN THE SHORT-TERM. BUT AS IN A LOT
OF SITUATIONS THE RAINFALL AMOUNTS HAVE BEEN ON THE HEAVIER SIDE
OF PREDICTION WITH SOME OF THESE SHOWERS. GFS/GEM STILL SEEM A
LITTLE HEAVIER THAN 12Z NAM AND ECMWF. COVERED BASES AND USED A
BLEND OF BOTH.

EMPLOYED NAM/ECMWF FOR PRESS/WINDS. REPLACED NAM WITH SREF AND
ADDED GEM/GFS FOR POP/QPF. FORECAST CONFIDENCE ON GOOD SIDE OF
AVERAGE.

.LONG TERM...UPPER LEVEL LOW/TROUGH WILL REMAIN IN THE GULF OF
ALASKA THROUGH THE FORECAST PERIOD DUE TO A BLOCKED PATTERN. THIS
LOW WILL CONTINUE TO SEND WAVES OF ENERGY OVER THE PANHANDLE AND
MAKE FOR A RATHER WET FORECAST. CHALLENGE WITH THESE SORT OF
SYSTEMS IS TIMING OF THE RAIN...AS THERE WILL BE BREAKS IN
BETWEEN. ALSO EACH MODEL PLACES THE WAVES OF ENERGY (VORT MAXES)
DIFFERENTLY WHICH RESULTS IN LARGER DIFFERENCES AT THE SURFACE.

OPTED TO USE AN ENSEMBLE APPROACH TO THE FORECAST WHICH MADE FOR
ONLY MINOR CHANGES. BIGGEST ADJUSTMENT WAS TO FLIP MANY OF THE
INSIDE WATERS DIRECTIONS TO SOUTHERLY. AS MENTIONED IN THE SHORT
TERM SECTION...FLOW AT ALL LEVELS AROUND THE GULF LOW WILL BE
S-SELY OVER THE PANHANDLE. THE SURFACE PRESSURE GRADIENT IN MANY
CASES WOULD SUGGEST A LIGHT NORTH WIND WHILE THE FLOW ALOFT WOULD
SUPPORT SOUTHERLY. OPTED TO GO FOR THE GEOSTROPHIC SOUTHERLY
FLOW...HOWEVER THERE ARE SOME TIME FRAMES WHERE THE NORTH WINDS
WILL WIN OUT...IE LIKE WHEN THE LOW CENTER IS SLIGHTLY MORE TO
THE SOUTH OR WHEN THERE IS A LIGHT DIURNAL SHIFT TO NORTH IN THE
EARLY MORNING HOURS.

CONTINUED WITH THE SMALLER DIURNAL TEMPERATURE RANGE UNDER THE
CLOUDY/RAINY CONDITIONS WITH LOWS IN THE LOWER 50S AND HIGHS IN
THE UPPER 50S. MOS GUIDANCE WOULD SUGGEST HIGHS IN THE LOWER 60S EACH
DAY...BUT THERE TENDS TO BE A WARM BIAS WITH THE MOS IN THESE
CONDITIONS. FORECAST CONFIDENCE ON WET IS ABOVE AVERAGE...BUT
LOWER ON TIMING OF EACH BAND OF PRECIP MOVING IN/OUT.

&&

.AJK WATCHES/WARNINGS/ADVISORIES...
PUBLIC...NONE.
MARINE...SMALL CRAFT ADVISORY FOR PKZ012-033-035-036-041-042.


$$

JWA/FERRIN








000
FXAK67 PAJK 242346
AFDAJK

SOUTHEAST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE JUNEAU AK
346 PM AKDT THU JUL 24 2014

.SHORT TERM...A SOMEWHAT AIMLESS LONGWAVE CUT-OFF LOW OVER THE
GULF OF ALASKA THAT WAS RESPONSIBLE FOR SOME FRONTAL RAINS THIS
MORNING AND SOME SHOWERS THIS AFTERNOON OVER THE PANHANDLE IS
PRIMED FOR SOME EXCITEMENT TONIGHT AS A SHORTWAVE ENERGY BURSTS
SOUTH ACROSS THE KATMAI. THIS ENERGY WILL DEEPEN THE
TROUGH...FARTHER ENOUGH INTO THE NORTH PACIFIC TO TAP SOME
SUBTROPICAL MOISTURE. THIS WILL BEGIN ROUNDING THE BEND NORTHWARD
INTO THE PANHANDLE STARTING FRIDAY AND CONTINUE INTO THE WEEKEND.
THE SHORTWAVE WILL DEVELOP A SURFACE LOW WEST OF HAIDA GWAII LATE
THURSDAY NIGHT THAT WILL DRIVE A FRONT INTO THE SOUTHERN
PANHANDLE INTO FRIDAY.

FIRST PRECIPITATION...RAIN THAT HAS FALLEN OVER THE AREA HAS BEEN
SPOTTY AND SOMEWHAT INTENSE IN NATURE. I SHOULD ADD THAT THE
ECMWF`S TREATMENT FOR YAKUTAT AS WET TURNED OUT TO BE MORE CORRECT
THAN THE MUCH DRIER GFS AND NAM. THUS THE CONVECTION CALLED FOR
TODAY WORKED OUT FAIRLY WELL. THIS COLD POOL ASSOCIATED WITH THE
LOW OVER THE GULF WILL SUPPORT SHOWERS THROUGH TONIGHT AND WILL
ONLY TRANSITION INTO MORE STEADY RAINS BEGINNING FRIDAY MORNING
FOR THE SOUTHERN PANHANDLE BEFORE EXTENDING AS FAR NORTH AS LYNN
CANAL BY THE AFTERNOON. NAM SOUNDINGS SUGGEST THAT AREAS CLOSEST
TO THE CORE OF THE UPPER LOW MAY STAY A LITTLE MORE UNSTABLE, WITH
A SOUTHERLY 850 JET SPREADING NORTHWARD, IT WAS HARD TO TURN
AGAINST THE CONCEPTUAL PARADIGM OF PRE-FRONTAL STRATIFORM...SO
JUST PAINTED EVERYTHING AS RAIN FOR FRIDAY AFTERNOON SOUTHWEST OF
YAKUTAT.

WINDS...NO BIG WORRIES EXCEPT FOR THE STRENGTH OF THE SOUTHERLIES
RISING IN THE SOUTH FRIDAY MORNING. SMALL CRAFTS FOR SOUTHERN
PASSAGES LOOKED GOOD. DID CONTINUE THE TREND OF BOOSTING WINDS FOR
BLOWHOLES LIKE HYDABURG AND ADDED SOME GUSTY LANGUAGE FOR SOUTHERN
BARANOF. PARTNER ON OUR DESK TODAY NOTICED THE WRF HAD CORRECTLY PREDICTED
THE GUSTINESS IN SITKA TODAY. WRF...WE MISSED YOU DURING YOUR
ABSENCE. ALWAYS A LITTLE SKETCHY ON STRENGTH AND EVEN DIRECTION OF
WINDS WHERE SURFACE GRADIENT RUNS COUNTER TO WINDS ALOFT. KIND OF
TOOK AN AVERAGE OF STRONG SOUTHERLIES AND WEAK NORTHERLIES TO
ARRIVE AT WEAK SOUTHERLIES FOR STEPHENS PASSAGE/NORTHERN CHATHAM.

NO BIG HYDRO ISSUES EXPECTED IN THE SHORT-TERM. BUT AS IN A LOT
OF SITUATIONS THE RAINFALL AMOUNTS HAVE BEEN ON THE HEAVIER SIDE
OF PREDICTION WITH SOME OF THESE SHOWERS. GFS/GEM STILL SEEM A
LITTLE HEAVIER THAN 12Z NAM AND ECMWF. COVERED BASES AND USED A
BLEND OF BOTH.

EMPLOYED NAM/ECMWF FOR PRESS/WINDS. REPLACED NAM WITH SREF AND
ADDED GEM/GFS FOR POP/QPF. FORECAST CONFIDENCE ON GOOD SIDE OF
AVERAGE.

.LONG TERM...UPPER LEVEL LOW/TROUGH WILL REMAIN IN THE GULF OF
ALASKA THROUGH THE FORECAST PERIOD DUE TO A BLOCKED PATTERN. THIS
LOW WILL CONTINUE TO SEND WAVES OF ENERGY OVER THE PANHANDLE AND
MAKE FOR A RATHER WET FORECAST. CHALLENGE WITH THESE SORT OF
SYSTEMS IS TIMING OF THE RAIN...AS THERE WILL BE BREAKS IN
BETWEEN. ALSO EACH MODEL PLACES THE WAVES OF ENERGY (VORT MAXES)
DIFFERENTLY WHICH RESULTS IN LARGER DIFFERENCES AT THE SURFACE.

OPTED TO USE AN ENSEMBLE APPROACH TO THE FORECAST WHICH MADE FOR
ONLY MINOR CHANGES. BIGGEST ADJUSTMENT WAS TO FLIP MANY OF THE
INSIDE WATERS DIRECTIONS TO SOUTHERLY. AS MENTIONED IN THE SHORT
TERM SECTION...FLOW AT ALL LEVELS AROUND THE GULF LOW WILL BE
S-SELY OVER THE PANHANDLE. THE SURFACE PRESSURE GRADIENT IN MANY
CASES WOULD SUGGEST A LIGHT NORTH WIND WHILE THE FLOW ALOFT WOULD
SUPPORT SOUTHERLY. OPTED TO GO FOR THE GEOSTROPHIC SOUTHERLY
FLOW...HOWEVER THERE ARE SOME TIME FRAMES WHERE THE NORTH WINDS
WILL WIN OUT...IE LIKE WHEN THE LOW CENTER IS SLIGHTLY MORE TO
THE SOUTH OR WHEN THERE IS A LIGHT DIURNAL SHIFT TO NORTH IN THE
EARLY MORNING HOURS.

CONTINUED WITH THE SMALLER DIURNAL TEMPERATURE RANGE UNDER THE
CLOUDY/RAINY CONDITIONS WITH LOWS IN THE LOWER 50S AND HIGHS IN
THE UPPER 50S. MOS GUIDANCE WOULD SUGGEST HIGHS IN THE LOWER 60S EACH
DAY...BUT THERE TENDS TO BE A WARM BIAS WITH THE MOS IN THESE
CONDITIONS. FORECAST CONFIDENCE ON WET IS ABOVE AVERAGE...BUT
LOWER ON TIMING OF EACH BAND OF PRECIP MOVING IN/OUT.

&&

.AJK WATCHES/WARNINGS/ADVISORIES...
PUBLIC...NONE.
MARINE...SMALL CRAFT ADVISORY FOR PKZ012-033-035-036-041-042.


$$

JWA/FERRIN









000
FXAK67 PAJK 241259
AFDAJK

SOUTHEAST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE JUNEAU AK
459 AM AKDT THU JUL 24 2014

.SHORT TERM...WATER VAPOR IMAGERY SHOWS UPPER LOWS OVER THE
NORTHERN GULF AND SOUTHEASTERN YUKON WITH UPPER LEVEL RIDGE BEING
PINCHED OVER THE PANHANDLE. A STRONG SHORTWAVE IS ALSO EVIDENT
ROUNDING THE BASE OF THE UPPER LOW. MODELS IN GOOD AGREEMENT WITH
THE MAIN LOW IN THE NORTHERN GULF DRIFTING E AS THE SHORTWAVE
MOVES INLAND NEAR HAIDA GWAII.

 MAIN FORECAST CHALLENGE THIS PERIOD WILL BE HOW QUICKLY THE
RIDGE WEAKENS AND PRECIP SPREADS ACROSS THE PANHANDLE. EXPECT
STRATIFORM PRECIP ACROSS THE NORTHERN PANHANDLE TO GRADUALLY
SPREAD E THIS AFTERNOON AND EVENING. THE REST OF THE PANHANDLE
CAN EXPECT SCATTERED SHOWERS THROUGH THE DAY TRANSITIONING TO
STRATIFORM PRECIP THIS EVENING AND OVERNIGHT. THE OTHER CONCERN
WILL BE WINDS ACROSS THE INNER CHANNELS AS THE PRESSURE GRADIENT
TIGHTENS. MARGINAL SMALL CRAFT LEVEL WINDS EXPECTED THIS
AFTERNOON/EVENING ACROSS NORTHERN LYNN. SOUTHERLY WINDS WILL
INCREASE OVERNIGHT ACROSS THE SOUTHERN COAST AND INNER CHANNELS
AS THE GRADIENT CONTINUES TO TIGHTEN IN RESPONSE TO THE
APPROACHING LOW.

.LONG TERM...MODELS IN GOOD AGREEMENT ON BLOCKY PATTERN
ALOFT...WITH UPPER TROF REMAINING OVER THE GULF INTO AT LEAST EARLY
NEXT WEEK. USED A 00Z ECMWF/GEM BLEND FOR FRI-SAT...THEN BLENDED
THE ECMWF WITH PREVIOUS FORECAST FOR SAT NIGHT.

FOR FRI-SAT NIGHT...WILL HAVE FRONT STALLED OVER THE ERN GULF
WITH A COUPLE OF LOWS MOVING N ALONG IT. THIS WILL KEEP MUCH OF
THE AREA WET DURING THIS TIME. WINDS WILL REMAIN AROUND SCA LEVELS
OVER THE FAR ERN GULF DURING THIS TIME. THE WET WEATHER WILL KEEP
TEMPERATURE RANGES ON THE SMALL SIDE...AND DID TIGHTEN UP THE
DIURNAL TEMPERATURE RANGE OVER MUCH OF THE AREA FOR FRI-SAT. MOST
PLACES WILL LIKELY STAY IN THE 50S DURING THIS TIME.

FOR THE REMAINING TIME FRAME...STILL LOOKS WET FOR MUCH OF THE
AREA INTO EARLY NEXT WEEK WITH UPPER TROF REMAINING OVER THE GULF.
MODELS HINT AT A SLOW RETROGRESSION OF THE TROF LATER IN THE
WEEK...WHICH COULD ALLOW FOR SOME DRIER CONDITIONS...BUT MODEL
DIFFERENCES FURTHER OUT MAKE FOR A LOW CONFIDENCE FORECAST AT THAT
TIME RANGE.

&&

.AJK WATCHES/WARNINGS/ADVISORIES...
PUBLIC...NONE.
MARINE...SMALL CRAFT ADVISORY FOR PKZ012.


$$

BC/RWT








000
FXAK67 PAJK 241259
AFDAJK

SOUTHEAST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE JUNEAU AK
459 AM AKDT THU JUL 24 2014

.SHORT TERM...WATER VAPOR IMAGERY SHOWS UPPER LOWS OVER THE
NORTHERN GULF AND SOUTHEASTERN YUKON WITH UPPER LEVEL RIDGE BEING
PINCHED OVER THE PANHANDLE. A STRONG SHORTWAVE IS ALSO EVIDENT
ROUNDING THE BASE OF THE UPPER LOW. MODELS IN GOOD AGREEMENT WITH
THE MAIN LOW IN THE NORTHERN GULF DRIFTING E AS THE SHORTWAVE
MOVES INLAND NEAR HAIDA GWAII.

 MAIN FORECAST CHALLENGE THIS PERIOD WILL BE HOW QUICKLY THE
RIDGE WEAKENS AND PRECIP SPREADS ACROSS THE PANHANDLE. EXPECT
STRATIFORM PRECIP ACROSS THE NORTHERN PANHANDLE TO GRADUALLY
SPREAD E THIS AFTERNOON AND EVENING. THE REST OF THE PANHANDLE
CAN EXPECT SCATTERED SHOWERS THROUGH THE DAY TRANSITIONING TO
STRATIFORM PRECIP THIS EVENING AND OVERNIGHT. THE OTHER CONCERN
WILL BE WINDS ACROSS THE INNER CHANNELS AS THE PRESSURE GRADIENT
TIGHTENS. MARGINAL SMALL CRAFT LEVEL WINDS EXPECTED THIS
AFTERNOON/EVENING ACROSS NORTHERN LYNN. SOUTHERLY WINDS WILL
INCREASE OVERNIGHT ACROSS THE SOUTHERN COAST AND INNER CHANNELS
AS THE GRADIENT CONTINUES TO TIGHTEN IN RESPONSE TO THE
APPROACHING LOW.

.LONG TERM...MODELS IN GOOD AGREEMENT ON BLOCKY PATTERN
ALOFT...WITH UPPER TROF REMAINING OVER THE GULF INTO AT LEAST EARLY
NEXT WEEK. USED A 00Z ECMWF/GEM BLEND FOR FRI-SAT...THEN BLENDED
THE ECMWF WITH PREVIOUS FORECAST FOR SAT NIGHT.

FOR FRI-SAT NIGHT...WILL HAVE FRONT STALLED OVER THE ERN GULF
WITH A COUPLE OF LOWS MOVING N ALONG IT. THIS WILL KEEP MUCH OF
THE AREA WET DURING THIS TIME. WINDS WILL REMAIN AROUND SCA LEVELS
OVER THE FAR ERN GULF DURING THIS TIME. THE WET WEATHER WILL KEEP
TEMPERATURE RANGES ON THE SMALL SIDE...AND DID TIGHTEN UP THE
DIURNAL TEMPERATURE RANGE OVER MUCH OF THE AREA FOR FRI-SAT. MOST
PLACES WILL LIKELY STAY IN THE 50S DURING THIS TIME.

FOR THE REMAINING TIME FRAME...STILL LOOKS WET FOR MUCH OF THE
AREA INTO EARLY NEXT WEEK WITH UPPER TROF REMAINING OVER THE GULF.
MODELS HINT AT A SLOW RETROGRESSION OF THE TROF LATER IN THE
WEEK...WHICH COULD ALLOW FOR SOME DRIER CONDITIONS...BUT MODEL
DIFFERENCES FURTHER OUT MAKE FOR A LOW CONFIDENCE FORECAST AT THAT
TIME RANGE.

&&

.AJK WATCHES/WARNINGS/ADVISORIES...
PUBLIC...NONE.
MARINE...SMALL CRAFT ADVISORY FOR PKZ012.


$$

BC/RWT









000
FXAK67 PAJK 232347
AFDAJK

SOUTHEAST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE JUNEAU AK
347 PM AKDT WED JUL 23 2014

.SHORT TERM...AFTERNOON SATELLITE IMAGE SHOWS A WEAK DEVELOPING
LOW EAST OF KODIAK ISLAND MOVES OVER THE NORTHERN GULF WITH ITS
ASSOCIATED WEAK OCCLUDED FRONT STRETCHING SOUTHEASTWARD ACROSS
THE EASTERN GULF. RAIN STARTED EARLY THIS MORNING OVER THE
NORTHEASTERN GULF COAST...INCLUDING YAKUTAT. A TRIPLE POINT
DEVELOPS ALONG THE SOUTHERN PART OF THE FRONTAL BOUNDARY AND
MOVES TOWARD HAIDA GWAII. AROUND THE LOW IN THE NORTHERN
GULF...PREVAILING SOUTHEAST WIND 15 TO 20 KNOTS REPORTED BY BUOY
46082.

 A WEAK RIDGE OF HIGH PRESSURE REMAINS OVER THE PANHANDLE AND
PRODUCES SMALL CRAFT LEVEL SOUTHERLY WINDS ACROSS NORTHERN LYNN
CANAL AND 15 TO 25 MPH SOUTHWEST WIND OVER SKAGWAY AREA. MOSTLY
SUNNY SKIES OVER THE SOUTHERN AREAS MAINTAINS DAYTIME
TEMPERATURES SOARING UP TO THE MID 60S. AHEAD OF THE INCOMING
FRONTAL PASSAGE...WEBCAM IMAGES SHOW GRADUAL INCREASE OF CLOUDS
THIS AFTERNOON ACROSS THE NORTHERN/CENTRAL PANHANDLE AND ALONG
THE PANHANDLE COASTAL AREAS. A PLENTY OF SUNSHINE CONTINUES OVER
THE SOUTHERN ZONES...BUT EXPECT INCREASING CLOUDS OVERNIGHT INTO
THURSDAY MORNING. CATEGORICAL POPS ACROSS THE NORTHEASTERN GULF
COAST TONIGHT WILL GRADUALLY DECREASE TO LIKELY POPS BY EARLY
THURSDAY. THE RAIN BAND WILL CONTINUE TO WEAKEN AS IT MOVES OVER
THE PANHANDLE THURSDAY AND PRODUCE CHANCE TO LIKELY POPS. NO
SIGNIFICANT QPF VALUES ARE DERIVED FROM MODEL OUTPUTS.

 MODELS REMAIN IN FAIR AGREEMENT FOR THE WEAKENING OCCLUDED FRONT
IN THE EASTERN GULF THIS EVENING DISSIPATES LATE TONIGHT AS IT
MOVES ONSHORE OVER THE PANHANDLE. USED A BLEND OF THE ECMWF AND
NAM FOR THEIR GOOD CONSENSUS THROUGH THURSDAY. A STRONGER FRONTAL
PASSAGE IS EXPECTED TO MOVE INTO THE EASTERN GULF LATE THURSDAY.
THE LOW IN THE NORTHERN GULF WILL SLOWLY DRIFT SOUTH TONIGHT THEN
MOVE EAST A LITTLE ON THURSDAY. THE RIDGE OF HIGH PRESSURE OVER
THE PANHANDLE WILL MOVE BACK AND FORTH IN RESPONSE TO THE LOW IN
THE GULF. SOUTHERLY SMALL CRAFT LEVEL WINDS ARE EXPECTED AGAIN
OVER NORTHERN LYNN CANAL BY LATE THURSDAY AFTERNOON.

.LONG TERM...LARGESCALE LOW OVER THE GULF WILL NEAR THE PANHANDLE
FROM THE WEST THURSDAY NIGHT. AFTER STUDYING SOME SOUNDINGS, THIS
COLD POOL ALOFT SHOULD INCREASE THE INSTABILITY ENOUGH FOR
PRECIPITATION TO BE MORE SHOWERY IN NATURE, SO KEPT THIS IDEA FROM
THE PREVIOUS ISSUANCE. PRECIPITATION SHOULD BECOME MORE PRE-
FRONTAL STRATIFORM FOR FRIDAY AS TEMPERATURES ALOFT WARM A TOUCH.
COOLED TEMPERATURES MAINLY BACK INTO THE 50S FOR FRIDAY SINCE RAIN
WILL TEND TO COOL TEMPERATURES AT THE SURFACE. COOLED TEMPS FOR
THE WEEKEND AS WELL, BUT COULD HAVE GONE COOLER AFTER BOOSTING
POPS TO CATEGORICAL FOR THE WEEKEND.

THIS WILL BE THE DEVELOPING STORY FOR THE WEEKEND. AS UPPER LOW
ENTRENCHES SOUTHWARD OVER THE GULF, THE TRAJECTORY OF SUBTROPICAL
MOISTURE WILL AIM NORTHEASTWARD TOWARD THE PANHANDLE. AT THIS
POINT, NOT GOING HEAVY FOR ANY SPOTS, BUT AS NOTED IN THE
HYDROLOGY PORTION OF THE DISCUSSION, TWO MODELS ARE SUGGESTING THE
POSSIBILITY. POPS WERE PUSHED TO CATEGORICAL FOR MOST ALL THE
PANHANDLE...ALTHOUGH WE DID DECREASE THEM A BIT FOR YAKUTAT. SOME
SOUTHEAST FLOW AT TIMES WHEN THE LOW OFFSHORE WILL TILT MORE
NEGATIVELY MAY KEEP AMOUNTS OF RAIN DOWN FOR NORTHERN INTERIOR
ZONES SUCH AS JUNEAU, BUT FEEL FAIRLY CONFIDENT THAT EVEN THESE
AREAS WILL BE WET. WHAT IS A LITTLE CONCERNING IS THAT SOUTHERLY
FLOW LOOKING MORE LIKE IT WILL PERSIST INTO NEXT WEEK, AND THAT
WILL KEEP RAIN CHANCES ON THE HIGH SIDE...SO FELT THE PREVIOUS
FORECAST WAS GOOD.

WINDS WILL BE GENERALLY ON THE LOWER SIDE...MAY GET A LITTLE
BREEZY ON FRIDAY ON PRINCE OF WALES AS FRONT PUSHES INTO THE
PANHANDLE. CLARENCE STRAIT/CROSS SOUND FROM THE SE AND E
RESPECTIVELY...SHOULD REACH 20 KT WITH THIS FRONT. THERE IS SOME
UNCERTAINTY IN THE MID-RANGE...WITH HOW THE MODELS SHORTWAVES
ROTATING AROUND THE MAIN UPPER LOW, BUT ALL TENDED TOWARDS A
SLOWER PROGRESSION OF THE ONE ROTATING NORTHWESTWARD FOR THE
WEEKEND, SO RESERVED THE BULK OF CHANGES FOR FRI NIGHT THROUGH
SUN.

PATTERN SO STABLE IN THE LONG-TERM THAT WPC LEANED HEAVILY ON 00Z
WED ECMWF THROUGH DAY 7...BUT THIS MADE LITTLE DIFFERENCE TO OUR
CURRENT FORECAST, SO NO REAL CHANGE TO EXTENDED FORECAST. ECMWF
USED FOR CHANGES DURING THE WEEKEND.

&&

.HYDROLOGY...AS UPPER LEVEL TROUGH DIGS SOUTHWARD OVER THE GULF TO
TAP SUBTROPICAL MOISTURE, AND THE WEEKEND`S SOUTHERLY FLOW
POSSIBLY LASTS THROUGH EARLY NEXT WEEK, RAINFALL AMOUNTS OVER THE
CWA WILL INCREASE, AND AT LEAST THE GEM AND THE GFS ARE
POTENTIALLY FLAGGING SOME BOUTS OF HEAVY RAIN OVER PARTS OF THE
PANHANDLE. MORE FOCUS WILL BE DIRECTED AT THE CHILKAT...THE
TAIYA...AND THE ALSEK RIVERS AS WEEKEND NEARS. BEST GUESS FOR NOW
IS THAT THESE RISES DO NOT OCCUR UNTIL SUNDAY AT LEAST.

&&

.AJK WATCHES/WARNINGS/ADVISORIES...
PUBLIC...NONE.
MARINE...SMALL CRAFT ADVISORY FOR PKZ012.


$$

AHN/JWA













000
FXAK67 PAJK 232347
AFDAJK

SOUTHEAST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE JUNEAU AK
347 PM AKDT WED JUL 23 2014

.SHORT TERM...AFTERNOON SATELLITE IMAGE SHOWS A WEAK DEVELOPING
LOW EAST OF KODIAK ISLAND MOVES OVER THE NORTHERN GULF WITH ITS
ASSOCIATED WEAK OCCLUDED FRONT STRETCHING SOUTHEASTWARD ACROSS
THE EASTERN GULF. RAIN STARTED EARLY THIS MORNING OVER THE
NORTHEASTERN GULF COAST...INCLUDING YAKUTAT. A TRIPLE POINT
DEVELOPS ALONG THE SOUTHERN PART OF THE FRONTAL BOUNDARY AND
MOVES TOWARD HAIDA GWAII. AROUND THE LOW IN THE NORTHERN
GULF...PREVAILING SOUTHEAST WIND 15 TO 20 KNOTS REPORTED BY BUOY
46082.

 A WEAK RIDGE OF HIGH PRESSURE REMAINS OVER THE PANHANDLE AND
PRODUCES SMALL CRAFT LEVEL SOUTHERLY WINDS ACROSS NORTHERN LYNN
CANAL AND 15 TO 25 MPH SOUTHWEST WIND OVER SKAGWAY AREA. MOSTLY
SUNNY SKIES OVER THE SOUTHERN AREAS MAINTAINS DAYTIME
TEMPERATURES SOARING UP TO THE MID 60S. AHEAD OF THE INCOMING
FRONTAL PASSAGE...WEBCAM IMAGES SHOW GRADUAL INCREASE OF CLOUDS
THIS AFTERNOON ACROSS THE NORTHERN/CENTRAL PANHANDLE AND ALONG
THE PANHANDLE COASTAL AREAS. A PLENTY OF SUNSHINE CONTINUES OVER
THE SOUTHERN ZONES...BUT EXPECT INCREASING CLOUDS OVERNIGHT INTO
THURSDAY MORNING. CATEGORICAL POPS ACROSS THE NORTHEASTERN GULF
COAST TONIGHT WILL GRADUALLY DECREASE TO LIKELY POPS BY EARLY
THURSDAY. THE RAIN BAND WILL CONTINUE TO WEAKEN AS IT MOVES OVER
THE PANHANDLE THURSDAY AND PRODUCE CHANCE TO LIKELY POPS. NO
SIGNIFICANT QPF VALUES ARE DERIVED FROM MODEL OUTPUTS.

 MODELS REMAIN IN FAIR AGREEMENT FOR THE WEAKENING OCCLUDED FRONT
IN THE EASTERN GULF THIS EVENING DISSIPATES LATE TONIGHT AS IT
MOVES ONSHORE OVER THE PANHANDLE. USED A BLEND OF THE ECMWF AND
NAM FOR THEIR GOOD CONSENSUS THROUGH THURSDAY. A STRONGER FRONTAL
PASSAGE IS EXPECTED TO MOVE INTO THE EASTERN GULF LATE THURSDAY.
THE LOW IN THE NORTHERN GULF WILL SLOWLY DRIFT SOUTH TONIGHT THEN
MOVE EAST A LITTLE ON THURSDAY. THE RIDGE OF HIGH PRESSURE OVER
THE PANHANDLE WILL MOVE BACK AND FORTH IN RESPONSE TO THE LOW IN
THE GULF. SOUTHERLY SMALL CRAFT LEVEL WINDS ARE EXPECTED AGAIN
OVER NORTHERN LYNN CANAL BY LATE THURSDAY AFTERNOON.

.LONG TERM...LARGESCALE LOW OVER THE GULF WILL NEAR THE PANHANDLE
FROM THE WEST THURSDAY NIGHT. AFTER STUDYING SOME SOUNDINGS, THIS
COLD POOL ALOFT SHOULD INCREASE THE INSTABILITY ENOUGH FOR
PRECIPITATION TO BE MORE SHOWERY IN NATURE, SO KEPT THIS IDEA FROM
THE PREVIOUS ISSUANCE. PRECIPITATION SHOULD BECOME MORE PRE-
FRONTAL STRATIFORM FOR FRIDAY AS TEMPERATURES ALOFT WARM A TOUCH.
COOLED TEMPERATURES MAINLY BACK INTO THE 50S FOR FRIDAY SINCE RAIN
WILL TEND TO COOL TEMPERATURES AT THE SURFACE. COOLED TEMPS FOR
THE WEEKEND AS WELL, BUT COULD HAVE GONE COOLER AFTER BOOSTING
POPS TO CATEGORICAL FOR THE WEEKEND.

THIS WILL BE THE DEVELOPING STORY FOR THE WEEKEND. AS UPPER LOW
ENTRENCHES SOUTHWARD OVER THE GULF, THE TRAJECTORY OF SUBTROPICAL
MOISTURE WILL AIM NORTHEASTWARD TOWARD THE PANHANDLE. AT THIS
POINT, NOT GOING HEAVY FOR ANY SPOTS, BUT AS NOTED IN THE
HYDROLOGY PORTION OF THE DISCUSSION, TWO MODELS ARE SUGGESTING THE
POSSIBILITY. POPS WERE PUSHED TO CATEGORICAL FOR MOST ALL THE
PANHANDLE...ALTHOUGH WE DID DECREASE THEM A BIT FOR YAKUTAT. SOME
SOUTHEAST FLOW AT TIMES WHEN THE LOW OFFSHORE WILL TILT MORE
NEGATIVELY MAY KEEP AMOUNTS OF RAIN DOWN FOR NORTHERN INTERIOR
ZONES SUCH AS JUNEAU, BUT FEEL FAIRLY CONFIDENT THAT EVEN THESE
AREAS WILL BE WET. WHAT IS A LITTLE CONCERNING IS THAT SOUTHERLY
FLOW LOOKING MORE LIKE IT WILL PERSIST INTO NEXT WEEK, AND THAT
WILL KEEP RAIN CHANCES ON THE HIGH SIDE...SO FELT THE PREVIOUS
FORECAST WAS GOOD.

WINDS WILL BE GENERALLY ON THE LOWER SIDE...MAY GET A LITTLE
BREEZY ON FRIDAY ON PRINCE OF WALES AS FRONT PUSHES INTO THE
PANHANDLE. CLARENCE STRAIT/CROSS SOUND FROM THE SE AND E
RESPECTIVELY...SHOULD REACH 20 KT WITH THIS FRONT. THERE IS SOME
UNCERTAINTY IN THE MID-RANGE...WITH HOW THE MODELS SHORTWAVES
ROTATING AROUND THE MAIN UPPER LOW, BUT ALL TENDED TOWARDS A
SLOWER PROGRESSION OF THE ONE ROTATING NORTHWESTWARD FOR THE
WEEKEND, SO RESERVED THE BULK OF CHANGES FOR FRI NIGHT THROUGH
SUN.

PATTERN SO STABLE IN THE LONG-TERM THAT WPC LEANED HEAVILY ON 00Z
WED ECMWF THROUGH DAY 7...BUT THIS MADE LITTLE DIFFERENCE TO OUR
CURRENT FORECAST, SO NO REAL CHANGE TO EXTENDED FORECAST. ECMWF
USED FOR CHANGES DURING THE WEEKEND.

&&

.HYDROLOGY...AS UPPER LEVEL TROUGH DIGS SOUTHWARD OVER THE GULF TO
TAP SUBTROPICAL MOISTURE, AND THE WEEKEND`S SOUTHERLY FLOW
POSSIBLY LASTS THROUGH EARLY NEXT WEEK, RAINFALL AMOUNTS OVER THE
CWA WILL INCREASE, AND AT LEAST THE GEM AND THE GFS ARE
POTENTIALLY FLAGGING SOME BOUTS OF HEAVY RAIN OVER PARTS OF THE
PANHANDLE. MORE FOCUS WILL BE DIRECTED AT THE CHILKAT...THE
TAIYA...AND THE ALSEK RIVERS AS WEEKEND NEARS. BEST GUESS FOR NOW
IS THAT THESE RISES DO NOT OCCUR UNTIL SUNDAY AT LEAST.

&&

.AJK WATCHES/WARNINGS/ADVISORIES...
PUBLIC...NONE.
MARINE...SMALL CRAFT ADVISORY FOR PKZ012.


$$

AHN/JWA












000
FXAK67 PAJK 231330
AFDAJK

SOUTHEAST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE JUNEAU AK
530 AM AKDT WED JUL 23 2014

.SHORT TERM...MORNING UPPER AIR ANALYSIS SHOWS A CLOSED LOW
ENTERING THE NRN GULF...WHILE DOWNSTREAM A RIDGE EXTENDING NEWD
FROM THE NRN PAC INTO SRN YUKON IS SHIFTING ACROSS THE ERN GULF.
ELSEWHERE...ANOTHER CLOSED LOW WAS POSITIONED OFFSHORE FROM
ORE/WA...WITH AN INVERTED TROUGH EXTENDING N INTO WRN BRITISH
COLUMBIA. AT THE SURFACE...WEAK LOW PRESSURE WAS LOCATED OVER THE
NWRN GULF...AND A SECOND LOW WAS POSITIONED OVER THE WRN YUKON
TERRITORY. RIDGE OF HIGH PRESSURE WAS LOCATED OVER THE SRN
PANHANDLE...WITH A SECOND HIGH PRESSURE AXIS EXTENDING NWWD
OFFSHORE OF YAKUTAT.

WEAK SURFACE FRONTAL BOUNDARY AND ASSOCIATED BAND OF THICKER CLOUD
COVER WAS MOVING TOWARD THE ERN GULF THIS MORNING. THIS AREA OF
RELATIVELY DEEPER MOISTURE WILL SPREAD ACROSS THE YAKUTAT AREA
DURING THE REMAINDER OF THE MORNING...AND THEN INTO CNTRL PORTIONS
OF THE PANHANDLE THROUGH THE AFTERNOON. RAIN CHANCES WILL
SUBSEQUENTLY INCREASE AS A RESULT. HOWEVER...INSPECTION OF 12Z
PAYA/PANT RAOBS AND SATELLITE DERIVED PW SHOW MEAGER MOISTURE
VALUES WILL ACCOMPANY THIS DISTURBANCE. THE LIMITED MOISTURE
COMBINED WITH WEAK FORCING FOR ASCENT IS EXPECTED TO YIELD FAIRLY
LIGHT RAINFALL TOTALS THROUGH WED NIGHT...WITH HIGHEST QPF VALUES
OCCURRING INVOF YAKUTAT. INCREASING CLOUD COVER OVER NRN/CNTRL
AREAS WILL LIMIT HIGH TEMPERATURES TO THE LOW-MID 60S...WHILE
GREATER INSOLATION OVER THE SRN PANHANDLE WILL AID IN BOOSTING
HIGHS INTO THE MID TO UPPER 60S.

SURFACE LOW PRESSURE OVER THE YUKON TERRITORY COMBINED WITH HIGH
PRESSURE EXTENDING INTO THE SRN PANHANDLE IS ALREADY YIELDING A
TIGHT GRADIENT OVER NRN LYNN CANAL AND SKAGWAY. THIS IS FORECAST
TO CONTINUE THROUGH THE EVENING RESULTING IN SLY SMALL CRAFT WINDS
OVER THE CANAL AND GUSTY CONDITIONS IN SKAGWAY.

FEW CHANGES WERE MADE TO THE INHERITED GRIDS. FORECAST CONFIDENCE
IN THE SHORT TERM IS ABOVE AVERAGE.

.LONG TERM...MODELS ARE IN FAIR AGREEMENT WITH AN UPPER LOW OVER
THE GULF BEING ABSORBED INTO A LONG WAVE TROUGH DIGGING INTO THE
GULF THIS WEEKEND. THE TROUGH WILL GRADUALLY FILL AND BEGIN A
GRADUAL SHIFT EAST EARLY NEXT WEEK.

WV IMAGERY SHOWS AN UPPER LOW MOVING OVER KODIAK ISLAND EARLY THIS
MORNING. THIS LOW WILL STALL OVER THE GULF AS IT RUNS INTO THE
UPPER RIDGE OVER BRITISH COLUMBIA. MODELS IN GOOD AGREEMENT WITH
THIS LOW MEANDERING AROUND THE NE GULF THU BEFORE BEING ABSORBED
INTO A DEEPENING LONG WAVE TROUGH FRI. MODELS BEGIN TO DIVERGE
MORE ON THE THE DETAILS DOWN TO THE SURFACE BY THIS WEEKEND.
ELECTED TO TREND GOING FORECAST TOWARDS A NAM/ECMWF BLEND THROUGH
SAT THEN AN WPC/EC BLEND THROUGH THE EXTENDED. MAIN CHANGE WAS TO
STRENGTHEN THE DEVELOPING SURFACE LOW OVER THE GULF THU-FRI. THIS
RESULTED IN INCREASES POPS ACROSS THE PANHANDLE AND STRONGER
WINDS...MAINLY OVER THE GULF. NAM CONTINUES TO SHOW 925MB WINDS SE
20-25 KT SOMETIME FRI/SAT BUT THE TIMING AND LOCATION OF STRONGEST
WINDS CHANGES WITH EACH MODEL RUN...SO NUDGED UP WINDS ACROSS THE
CHANNELS SLIGHTLY DURING THIS TIMEFRAME.

OVERALL...MAINTAINED HIGH POPS THROUGH THE WEEKEND AS MINOR
IMPULSES ROTATING AROUND THE UPPER LOW IN THE GULF TRIGGER PERIODS
OF RAIN ACROSS SE AK. MODELS IN FAIR AGREEMENT WITH THE LOW
BEGINNING TO FILL EARLY NEXT WEEK AS IT CONTINUES TO MEANDER OVER
THE GULF SO TRENDED POPS DOWN SLIGHTLY THROUGH THE EXTENDED.

&&

.AVIATION...LOW CLOUDS AND MIST WILL PERSIST OVER PAYA DURING THE
DAY...WITH RAIN FORECAST TO BEGIN BY LATE MORNING. SOUTH-
SOUTHWESTERLY WINDS UP TO 20 KT ARE EXPECTED THIS AFTERNOON IN
PAGY. OTHERWISE...MIDLEVEL CLOUDS WILL INCREASE ACROSS MUCH OF THE
PANHANDLE...WITH LIGHT RAIN POSSIBLE OVER PASI AND PAGS BY
EVENING. ELSEWHERE...CONTINUED WITH VCSH.

&&

.MARINE...TIGHT PRESSURE GRADIENT OVER NRN LYNN CANAL WILL YIELD
SLY SMALL CRAFT WINDS THROUGH THIS EVENING. ELSEWHERE WINDS ARE
FORECAST TO REMAIN AOB 20 KT. CLOUDS WILL THICKEN OVER THE
NRN/CNTRL INNER CHANNELS AS WELL AS OFFSHORE...WITH LIGHT RAIN
BECOMING INCREASINGLY PROBABLE THROUGH THE DAY.

&&

.AJK WATCHES/WARNINGS/ADVISORIES...
PUBLIC...NONE.
MARINE...SMALL CRAFT ADVISORY FOR PKZ012.

&&

$$

GARNER/BC






000
FXAK67 PAJK 231330
AFDAJK

SOUTHEAST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE JUNEAU AK
530 AM AKDT WED JUL 23 2014

.SHORT TERM...MORNING UPPER AIR ANALYSIS SHOWS A CLOSED LOW
ENTERING THE NRN GULF...WHILE DOWNSTREAM A RIDGE EXTENDING NEWD
FROM THE NRN PAC INTO SRN YUKON IS SHIFTING ACROSS THE ERN GULF.
ELSEWHERE...ANOTHER CLOSED LOW WAS POSITIONED OFFSHORE FROM
ORE/WA...WITH AN INVERTED TROUGH EXTENDING N INTO WRN BRITISH
COLUMBIA. AT THE SURFACE...WEAK LOW PRESSURE WAS LOCATED OVER THE
NWRN GULF...AND A SECOND LOW WAS POSITIONED OVER THE WRN YUKON
TERRITORY. RIDGE OF HIGH PRESSURE WAS LOCATED OVER THE SRN
PANHANDLE...WITH A SECOND HIGH PRESSURE AXIS EXTENDING NWWD
OFFSHORE OF YAKUTAT.

WEAK SURFACE FRONTAL BOUNDARY AND ASSOCIATED BAND OF THICKER CLOUD
COVER WAS MOVING TOWARD THE ERN GULF THIS MORNING. THIS AREA OF
RELATIVELY DEEPER MOISTURE WILL SPREAD ACROSS THE YAKUTAT AREA
DURING THE REMAINDER OF THE MORNING...AND THEN INTO CNTRL PORTIONS
OF THE PANHANDLE THROUGH THE AFTERNOON. RAIN CHANCES WILL
SUBSEQUENTLY INCREASE AS A RESULT. HOWEVER...INSPECTION OF 12Z
PAYA/PANT RAOBS AND SATELLITE DERIVED PW SHOW MEAGER MOISTURE
VALUES WILL ACCOMPANY THIS DISTURBANCE. THE LIMITED MOISTURE
COMBINED WITH WEAK FORCING FOR ASCENT IS EXPECTED TO YIELD FAIRLY
LIGHT RAINFALL TOTALS THROUGH WED NIGHT...WITH HIGHEST QPF VALUES
OCCURRING INVOF YAKUTAT. INCREASING CLOUD COVER OVER NRN/CNTRL
AREAS WILL LIMIT HIGH TEMPERATURES TO THE LOW-MID 60S...WHILE
GREATER INSOLATION OVER THE SRN PANHANDLE WILL AID IN BOOSTING
HIGHS INTO THE MID TO UPPER 60S.

SURFACE LOW PRESSURE OVER THE YUKON TERRITORY COMBINED WITH HIGH
PRESSURE EXTENDING INTO THE SRN PANHANDLE IS ALREADY YIELDING A
TIGHT GRADIENT OVER NRN LYNN CANAL AND SKAGWAY. THIS IS FORECAST
TO CONTINUE THROUGH THE EVENING RESULTING IN SLY SMALL CRAFT WINDS
OVER THE CANAL AND GUSTY CONDITIONS IN SKAGWAY.

FEW CHANGES WERE MADE TO THE INHERITED GRIDS. FORECAST CONFIDENCE
IN THE SHORT TERM IS ABOVE AVERAGE.

.LONG TERM...MODELS ARE IN FAIR AGREEMENT WITH AN UPPER LOW OVER
THE GULF BEING ABSORBED INTO A LONG WAVE TROUGH DIGGING INTO THE
GULF THIS WEEKEND. THE TROUGH WILL GRADUALLY FILL AND BEGIN A
GRADUAL SHIFT EAST EARLY NEXT WEEK.

WV IMAGERY SHOWS AN UPPER LOW MOVING OVER KODIAK ISLAND EARLY THIS
MORNING. THIS LOW WILL STALL OVER THE GULF AS IT RUNS INTO THE
UPPER RIDGE OVER BRITISH COLUMBIA. MODELS IN GOOD AGREEMENT WITH
THIS LOW MEANDERING AROUND THE NE GULF THU BEFORE BEING ABSORBED
INTO A DEEPENING LONG WAVE TROUGH FRI. MODELS BEGIN TO DIVERGE
MORE ON THE THE DETAILS DOWN TO THE SURFACE BY THIS WEEKEND.
ELECTED TO TREND GOING FORECAST TOWARDS A NAM/ECMWF BLEND THROUGH
SAT THEN AN WPC/EC BLEND THROUGH THE EXTENDED. MAIN CHANGE WAS TO
STRENGTHEN THE DEVELOPING SURFACE LOW OVER THE GULF THU-FRI. THIS
RESULTED IN INCREASES POPS ACROSS THE PANHANDLE AND STRONGER
WINDS...MAINLY OVER THE GULF. NAM CONTINUES TO SHOW 925MB WINDS SE
20-25 KT SOMETIME FRI/SAT BUT THE TIMING AND LOCATION OF STRONGEST
WINDS CHANGES WITH EACH MODEL RUN...SO NUDGED UP WINDS ACROSS THE
CHANNELS SLIGHTLY DURING THIS TIMEFRAME.

OVERALL...MAINTAINED HIGH POPS THROUGH THE WEEKEND AS MINOR
IMPULSES ROTATING AROUND THE UPPER LOW IN THE GULF TRIGGER PERIODS
OF RAIN ACROSS SE AK. MODELS IN FAIR AGREEMENT WITH THE LOW
BEGINNING TO FILL EARLY NEXT WEEK AS IT CONTINUES TO MEANDER OVER
THE GULF SO TRENDED POPS DOWN SLIGHTLY THROUGH THE EXTENDED.

&&

.AVIATION...LOW CLOUDS AND MIST WILL PERSIST OVER PAYA DURING THE
DAY...WITH RAIN FORECAST TO BEGIN BY LATE MORNING. SOUTH-
SOUTHWESTERLY WINDS UP TO 20 KT ARE EXPECTED THIS AFTERNOON IN
PAGY. OTHERWISE...MIDLEVEL CLOUDS WILL INCREASE ACROSS MUCH OF THE
PANHANDLE...WITH LIGHT RAIN POSSIBLE OVER PASI AND PAGS BY
EVENING. ELSEWHERE...CONTINUED WITH VCSH.

&&

.MARINE...TIGHT PRESSURE GRADIENT OVER NRN LYNN CANAL WILL YIELD
SLY SMALL CRAFT WINDS THROUGH THIS EVENING. ELSEWHERE WINDS ARE
FORECAST TO REMAIN AOB 20 KT. CLOUDS WILL THICKEN OVER THE
NRN/CNTRL INNER CHANNELS AS WELL AS OFFSHORE...WITH LIGHT RAIN
BECOMING INCREASINGLY PROBABLE THROUGH THE DAY.

&&

.AJK WATCHES/WARNINGS/ADVISORIES...
PUBLIC...NONE.
MARINE...SMALL CRAFT ADVISORY FOR PKZ012.

&&

$$

GARNER/BC





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