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000
FXAK67 PAJK 301435
AFDAJK

SOUTHEAST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE JUNEAU AK
535 AM AKST FRI JAN 30 2015

.SHORT TERM...LOW AMPLITUDE UPPER IMPULSE IS APPROACHING HAIDA
GWAII EARLY THIS MORNING. THIS FEATURE AND ASSOCIATED AREA OF
SURFACE LOW PRESSURE WILL EXIT E INTO BC DURING THE
AFTERNOON...WITH UPPER RIDGING OCCURRING IN ITS WAKE OVER THE
GULF. SHEARED OUT NRN STREAM TROUGH WILL THEN SLIDE SE ACROSS NWRN
CANADA AND THE NRN PANHANDLE TONIGHT. MEANWHILE...UPPER-LEVEL
SUBSIDENCE IS OCCURRING OVER THE SRN/CNTRL PANHANDLE THIS
MORNING...AND WHEN COMBINED WITH A MOIST BOUNDARY LAYER /DUE TO
RECENT RAIN AND MELTING SNOW/...IS AIDING IN FOG
DEVELOPMENT...WHICH HAS BEEN LOCALLY DENSE OVER JUNEAU AS WELL AS
PETERSBURG AND WRANGELL. FOG IS EXPECTED TO DISSIPATE BY MID TO
LATE MORNING...WITH BREAKS IN LOW CLOUDS POSSIBLY YIELDING
SUNSHINE FOR CNTRL/SRN AREAS THIS AFTERNOON. OVER THE NRN
PANHANDLE...DEEPER MOISTURE WILL FAVOR GREATER CLOUD COVER DURING
THE DAY...PARTICULARLY OVER YAKUTAT WHERE PERIODS OF LIGHT SNOW
AND RAIN ARE EXPECTED THIS MORNING. ASCENT WILL DECREASE OVER THIS
AREA GOING INTO TONIGHT...AND CLOUDS WILL EVENTUALLY DISSIPATE
TOWARD THE END OF THE SHORT TERM PERIOD. THE END RESULT WILL BE A
PRECIPITATION FREE CWA TOWARD 12-15Z SAT...AS WELL AS COLDER LOW
TEMPERATURES.

STRONG OFFSHORE ORIENTED SURFACE PRESSURE GRADIENT IS FORECAST TO
DEVELOP TONIGHT...WHICH WILL FURTHER AID IN DRYING THE AIRMASS
ACROSS THE PANHANDLE. OF GREATER CONCERN WILL BE STRENGTHENING NLY
WINDS OVER THE NRN/CNTRL INSIDE WATERS...AND E-NELYS OVER CROSS
SOUND AND ICY STRAIT. STORM FORCE WINDS ARE PROBABLE FOR NRN LYNN
CANAL LATE TONIGHT...AND GALES ARE EXPECTED FOR SRN LYNN AND
STEPHENS PASSAGE. A STRONG WIND HEADLINE HAS ALSO BEEN POSTED FOR
SKAGWAY. FARTHER S OVER DOWNTOWN JUNEAU AND S DOUGLAS...MOUNTAIN
WAVE DEVELOPMENT WILL BE IN IT/S INCIPIENT STAGE LATE
TONIGHT...AND THUS...HAVE HELD OFF ON ISSUANCE OF STRONG WIND
HEADLINE ATTM. HOWEVER...DAY SHIFT WILL NEED TO RE-EVALUATE THE
START TIME FOR STRONG WINDS.

NUDGED PRESSURE GRIDS TOWARD THE NAM AND ECMWF THIS
AFTERNOON/EVENING...THEN CONTINUED WITH INHERITED FOR THE
REMAINDER OF THE SHORT TERM. MODEL GUIDANCE CONTINUES TO SHOW
POP/QPF DECREASING GOING INTO TONIGHT...WHICH SUPPORTS PREVIOUS
FORECAST THINKING.

.LONG TERM...BEGINNING OF THE LONG RANGE PERIOD SEES THE OUTFLOW
WINDS STARTING TO GET INTO GEAR ON SAT. SURFACE PRESSURES ACROSS
THE SOUTHERN YUKON WILL HAVE BALLOONED TO 1045 MB BY THIS POINT
WITH CROSS COAST MOUNTAIN PRESSURE GRADIENTS REACHING 10 TO 15 MB.
THE COLD ARCTIC AIR THAT WILL BE SPILLING OVER THE MOUNTAIN PASSES
WILL ONLY ADD TO THE WINDS. AS USUAL, LYNN CANAL WILL LIKELY BE THE
WINDIEST SPOT WITH STORM FORCE WINDS EXPECTED FOR MUCH OF THE
WEEKEND. NOT TO BE OUTDONE, SKAGWAY, DISENCHANTMENT BAY, TAKU
INLET, AND THE PASSES EAST OF YAKUTAT WILL ALSO BE GUSTING THROUGH
OUT THE WEEKEND WITH GUSTS IN THE 40 TO 50 MPH RANGE.

THE COLD OUTFLOW WILL ALSO PROMOTE THE POSSIBILITY OF A STRONG
MOUNTAIN WAVE WIND EVENT FOR DOWNTOWN JUNEAU AND DOUGLAS THIS
WEEKEND. CROSS BARRIER FLOW IS EXPECTED TO BE AROUND 35 TO 45 KT
WITH THE HIGHEST FLOW EXPECTED SAT NIGHT. AN INVERSION ABOVE RIDGE
TOP WILL ALSO BE IN PLACE WITH THE COLD OUTFLOW. THE LIMITING
FACTOR MAY BE THE CRITICAL LEVEL. THE CRITICAL LEVEL ON MODEL
SOUNDINGS IS RATHER WELL DEFINED WITH A CLEAR DIRECTION SHIFT.
HOWEVER, IT IS RATHER LOW AT 700 MB TO START. THIS BECOMES MORE
FAVORABLE BY SAT NIGHT AS IT RISES TO AROUND 400 TO 500 MB.
CURRENTLY EXPECTING GUSTS IN EXCESS OF 55 MPH AT MOST SAT NIGHT.
THE WINDS FALL APART AFTER THAT AS THE CRITICAL LEVEL GETS
OBLITERATED BY GENERAL NE FLOW IN ALL LEVELS.

MEANWHILE THE SOUTHERN THIRD OF THE PANHANDLE WILL BE DEALING WITH
THE REASON THAT THE NORTHERLY PRESSURE GRADIENT WILL BE SO HIGH. A
WEAKENING FRONT WILL BE TRYING TO PUSH NORTH SAT INTO SUN BUT WILL
NOT MAKE MUCH PROGRESS DUE TO THE BLOCKING HIGH TO THE NORTH. WHAT
IT WILL DO IS BRING SOME GALE FORCE WINDS TO THE GULF OVER THE
WEEKEND AS WELL AS SOME PRECIP FOR THE SOUTHERN PANHANDLE. THE
GALE FORCE WINDS WILL MAINLY BE RELEGATED TO THE OFFSHORE ZONE ON
SAT AND WILL GRADUALLY DIMINISH TO SMALL CRAFT CRITERIA BY SUN AS
THE FRONT FALLS APART UNDER THE DIFLUENT FLOW ALOFT AND THE
DRY OUTFLOW WINDS AT THE SURFACE. ANY PRECIP WILL NOT GET THAT FAR
NORTH FOR THE SAME REASON. SO ONLY HAVE LIKELY POPS AS FAR NORTH
AS SUNMER STRAIT BY SUN. PRECIP AMOUNTS WILL BE LIGHT WITH THE
FRONT FALLING APART.

FARTHER OUT DRY WEATHER CONTINUES INTO AT LEAST MID WEEK BUT
OUTFLOW WINDS DIMINISH AS THE YUKON HIGH SLIDES SOUTHEAST INTO
CENTRAL BC TAKING MOST OF ITS COLD AIR WITH IT. THINGS START TO
GET A BIT MURKY HERE AS SOME MODELS START TO BRING ANOTHER
NORTHERN STREAM TROUGH OUT OF SIBERIA. HOW FAR EAST IT GETS IS UP
FOR DEBATE ESPECIALLY AS IT STARTS TO INTERACT WITH THE SOUTHERN
STREAM JET LATE WEEK WHICH SPINS UP A MORE SUBSTANTIAL STORM INTO
THE EASTERN GULF FOR FRI. TIMING, STRENGTH AND STRUCTURE ARE ALL
UP FOR DEBATE HERE SO FORECAST CONFIDENCE FALTERS PAST MID WEEK.

LONG RANGE MODELS WERE IN DECENT AGREEMENT UP UNTIL EARLY TO MID
NEXT WEEK. GENERALLY FAVORED THE NAM/ECMWF/GEM FOR UPDATES. MOST
OF THE CHANGES WERE FOR SUN NIGHT INTO MON TO STRETCH OUT THE
OUTFLOW WINDS A BIT LONGER AS SUGGESTED BY THE GUIDANCE.



&&

.AJK WATCHES/WARNINGS/ADVISORIES...
PUBLIC...DENSE FOG ADVISORY UNTIL 10 AM AKST THIS MORNING FOR AKZ026.
         DENSE FOG ADVISORY UNTIL 6 AM AKST EARLY THIS MORNING FOR AKZ025.
         STRONG WIND FROM NOON AKST TODAY THROUGH LATE TONIGHT FOR AKZ018.
MARINE...STORM WARNING FOR PKZ012.
         GALE WARNING FOR PKZ013-031.
         SMALL CRAFT ADVISORY FOR PKZ011-021-022-032-034-035-043-053.

&&

$$

GARNER/EAL

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










000
FXAK67 PAJK 301435
AFDAJK

SOUTHEAST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE JUNEAU AK
535 AM AKST FRI JAN 30 2015

.SHORT TERM...LOW AMPLITUDE UPPER IMPULSE IS APPROACHING HAIDA
GWAII EARLY THIS MORNING. THIS FEATURE AND ASSOCIATED AREA OF
SURFACE LOW PRESSURE WILL EXIT E INTO BC DURING THE
AFTERNOON...WITH UPPER RIDGING OCCURRING IN ITS WAKE OVER THE
GULF. SHEARED OUT NRN STREAM TROUGH WILL THEN SLIDE SE ACROSS NWRN
CANADA AND THE NRN PANHANDLE TONIGHT. MEANWHILE...UPPER-LEVEL
SUBSIDENCE IS OCCURRING OVER THE SRN/CNTRL PANHANDLE THIS
MORNING...AND WHEN COMBINED WITH A MOIST BOUNDARY LAYER /DUE TO
RECENT RAIN AND MELTING SNOW/...IS AIDING IN FOG
DEVELOPMENT...WHICH HAS BEEN LOCALLY DENSE OVER JUNEAU AS WELL AS
PETERSBURG AND WRANGELL. FOG IS EXPECTED TO DISSIPATE BY MID TO
LATE MORNING...WITH BREAKS IN LOW CLOUDS POSSIBLY YIELDING
SUNSHINE FOR CNTRL/SRN AREAS THIS AFTERNOON. OVER THE NRN
PANHANDLE...DEEPER MOISTURE WILL FAVOR GREATER CLOUD COVER DURING
THE DAY...PARTICULARLY OVER YAKUTAT WHERE PERIODS OF LIGHT SNOW
AND RAIN ARE EXPECTED THIS MORNING. ASCENT WILL DECREASE OVER THIS
AREA GOING INTO TONIGHT...AND CLOUDS WILL EVENTUALLY DISSIPATE
TOWARD THE END OF THE SHORT TERM PERIOD. THE END RESULT WILL BE A
PRECIPITATION FREE CWA TOWARD 12-15Z SAT...AS WELL AS COLDER LOW
TEMPERATURES.

STRONG OFFSHORE ORIENTED SURFACE PRESSURE GRADIENT IS FORECAST TO
DEVELOP TONIGHT...WHICH WILL FURTHER AID IN DRYING THE AIRMASS
ACROSS THE PANHANDLE. OF GREATER CONCERN WILL BE STRENGTHENING NLY
WINDS OVER THE NRN/CNTRL INSIDE WATERS...AND E-NELYS OVER CROSS
SOUND AND ICY STRAIT. STORM FORCE WINDS ARE PROBABLE FOR NRN LYNN
CANAL LATE TONIGHT...AND GALES ARE EXPECTED FOR SRN LYNN AND
STEPHENS PASSAGE. A STRONG WIND HEADLINE HAS ALSO BEEN POSTED FOR
SKAGWAY. FARTHER S OVER DOWNTOWN JUNEAU AND S DOUGLAS...MOUNTAIN
WAVE DEVELOPMENT WILL BE IN IT/S INCIPIENT STAGE LATE
TONIGHT...AND THUS...HAVE HELD OFF ON ISSUANCE OF STRONG WIND
HEADLINE ATTM. HOWEVER...DAY SHIFT WILL NEED TO RE-EVALUATE THE
START TIME FOR STRONG WINDS.

NUDGED PRESSURE GRIDS TOWARD THE NAM AND ECMWF THIS
AFTERNOON/EVENING...THEN CONTINUED WITH INHERITED FOR THE
REMAINDER OF THE SHORT TERM. MODEL GUIDANCE CONTINUES TO SHOW
POP/QPF DECREASING GOING INTO TONIGHT...WHICH SUPPORTS PREVIOUS
FORECAST THINKING.

.LONG TERM...BEGINNING OF THE LONG RANGE PERIOD SEES THE OUTFLOW
WINDS STARTING TO GET INTO GEAR ON SAT. SURFACE PRESSURES ACROSS
THE SOUTHERN YUKON WILL HAVE BALLOONED TO 1045 MB BY THIS POINT
WITH CROSS COAST MOUNTAIN PRESSURE GRADIENTS REACHING 10 TO 15 MB.
THE COLD ARCTIC AIR THAT WILL BE SPILLING OVER THE MOUNTAIN PASSES
WILL ONLY ADD TO THE WINDS. AS USUAL, LYNN CANAL WILL LIKELY BE THE
WINDIEST SPOT WITH STORM FORCE WINDS EXPECTED FOR MUCH OF THE
WEEKEND. NOT TO BE OUTDONE, SKAGWAY, DISENCHANTMENT BAY, TAKU
INLET, AND THE PASSES EAST OF YAKUTAT WILL ALSO BE GUSTING THROUGH
OUT THE WEEKEND WITH GUSTS IN THE 40 TO 50 MPH RANGE.

THE COLD OUTFLOW WILL ALSO PROMOTE THE POSSIBILITY OF A STRONG
MOUNTAIN WAVE WIND EVENT FOR DOWNTOWN JUNEAU AND DOUGLAS THIS
WEEKEND. CROSS BARRIER FLOW IS EXPECTED TO BE AROUND 35 TO 45 KT
WITH THE HIGHEST FLOW EXPECTED SAT NIGHT. AN INVERSION ABOVE RIDGE
TOP WILL ALSO BE IN PLACE WITH THE COLD OUTFLOW. THE LIMITING
FACTOR MAY BE THE CRITICAL LEVEL. THE CRITICAL LEVEL ON MODEL
SOUNDINGS IS RATHER WELL DEFINED WITH A CLEAR DIRECTION SHIFT.
HOWEVER, IT IS RATHER LOW AT 700 MB TO START. THIS BECOMES MORE
FAVORABLE BY SAT NIGHT AS IT RISES TO AROUND 400 TO 500 MB.
CURRENTLY EXPECTING GUSTS IN EXCESS OF 55 MPH AT MOST SAT NIGHT.
THE WINDS FALL APART AFTER THAT AS THE CRITICAL LEVEL GETS
OBLITERATED BY GENERAL NE FLOW IN ALL LEVELS.

MEANWHILE THE SOUTHERN THIRD OF THE PANHANDLE WILL BE DEALING WITH
THE REASON THAT THE NORTHERLY PRESSURE GRADIENT WILL BE SO HIGH. A
WEAKENING FRONT WILL BE TRYING TO PUSH NORTH SAT INTO SUN BUT WILL
NOT MAKE MUCH PROGRESS DUE TO THE BLOCKING HIGH TO THE NORTH. WHAT
IT WILL DO IS BRING SOME GALE FORCE WINDS TO THE GULF OVER THE
WEEKEND AS WELL AS SOME PRECIP FOR THE SOUTHERN PANHANDLE. THE
GALE FORCE WINDS WILL MAINLY BE RELEGATED TO THE OFFSHORE ZONE ON
SAT AND WILL GRADUALLY DIMINISH TO SMALL CRAFT CRITERIA BY SUN AS
THE FRONT FALLS APART UNDER THE DIFLUENT FLOW ALOFT AND THE
DRY OUTFLOW WINDS AT THE SURFACE. ANY PRECIP WILL NOT GET THAT FAR
NORTH FOR THE SAME REASON. SO ONLY HAVE LIKELY POPS AS FAR NORTH
AS SUNMER STRAIT BY SUN. PRECIP AMOUNTS WILL BE LIGHT WITH THE
FRONT FALLING APART.

FARTHER OUT DRY WEATHER CONTINUES INTO AT LEAST MID WEEK BUT
OUTFLOW WINDS DIMINISH AS THE YUKON HIGH SLIDES SOUTHEAST INTO
CENTRAL BC TAKING MOST OF ITS COLD AIR WITH IT. THINGS START TO
GET A BIT MURKY HERE AS SOME MODELS START TO BRING ANOTHER
NORTHERN STREAM TROUGH OUT OF SIBERIA. HOW FAR EAST IT GETS IS UP
FOR DEBATE ESPECIALLY AS IT STARTS TO INTERACT WITH THE SOUTHERN
STREAM JET LATE WEEK WHICH SPINS UP A MORE SUBSTANTIAL STORM INTO
THE EASTERN GULF FOR FRI. TIMING, STRENGTH AND STRUCTURE ARE ALL
UP FOR DEBATE HERE SO FORECAST CONFIDENCE FALTERS PAST MID WEEK.

LONG RANGE MODELS WERE IN DECENT AGREEMENT UP UNTIL EARLY TO MID
NEXT WEEK. GENERALLY FAVORED THE NAM/ECMWF/GEM FOR UPDATES. MOST
OF THE CHANGES WERE FOR SUN NIGHT INTO MON TO STRETCH OUT THE
OUTFLOW WINDS A BIT LONGER AS SUGGESTED BY THE GUIDANCE.



&&

.AJK WATCHES/WARNINGS/ADVISORIES...
PUBLIC...DENSE FOG ADVISORY UNTIL 10 AM AKST THIS MORNING FOR AKZ026.
         DENSE FOG ADVISORY UNTIL 6 AM AKST EARLY THIS MORNING FOR AKZ025.
         STRONG WIND FROM NOON AKST TODAY THROUGH LATE TONIGHT FOR AKZ018.
MARINE...STORM WARNING FOR PKZ012.
         GALE WARNING FOR PKZ013-031.
         SMALL CRAFT ADVISORY FOR PKZ011-021-022-032-034-035-043-053.

&&

$$

GARNER/EAL

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











000
FXAK67 PAJK 300054
AFDAJK

SOUTHEAST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE JUNEAU AK
354 PM AKST THU JAN 29 2015

.SHORT TERM...SOME COLDER AIR REMAINS IN PLACE AND THE ARCTIC
FRONT HAS REMAINED AS FAR SOUTH AS THE AUKE BAY AREA FOR A GOOD
PORTION OF THE DAY TODAY. SNOW SHOWERS AT THE BACK OF THE
MENDENHALL VALLEY TOTALED MORE THAN 1/2 INCH BEFORE FINALLY
WARMING UP ABOVE FREEZING. FARTHER NORTH, HEAVY SNOW CONTINUED TO
FALL AT THE KENSINGTON MINE INTO THE AFTERNOON. THE FRONTAL
FEATURE THAT RESULTED IN HEAVY SNOW IN HAINES AND SKAGWAY
OVERNIGHT IS WEAKENING AS IT CONTINUES TO SLOWLY MOVE NORTH.
SCATTERED RAIN AND SNOW SHOWERS WILL CONTINUE THROUGH THE EVENING
AND THEN DIMINISH TO AN END OVERNIGHT FOR THE NORTHERN ZONES WITH
SCATTERED SHOWER ACTIVITY IN THE YAKUTAT AREA CONTINUING THROUGH
THE NIGHT. MORE SOUTHERLY LOCATIONS HAVE BEEN DRY FOR THE MOST PART
SINCE LATE MORNING.

THERE HAVE BEEN SOME BREAKS IN THE CLOUD COVER TODAY...PRIMARILY OVER
THE SOUTHERN PANHANDLE...AND MORE BREAKS WILL SHOW UP FARTHER
NORTH. ENOUGH SO THAT FOG HAS BEEN INCLUDED IN SOME OF THE
PANHANDLE TAF SITES. WHATEVER FOG DOES FORM SHOULD DISPERSE
QUICKLY TOMORROW WITH THE FIRST LIGHT WINDS OF THE DAY.

WINDS AND SEAS NOT MUCH OF A FACTOR THROUGH TONIGHT. A LONG PERIOD
(8 TO 10 SECONDS) 8 FOOT SWELL DOMINATES MOST OF THE OUTER COAST,
BUT VERY LITTLE IN THE WAY OF WIND WAVE. AN OFFSHORE GRADIENT WILL
INTENSIFY TOMORROW OVER THE FAR NORTHERN INNER CHANNELS. LOOK FOR
NORTHERLY GALES TO 40 KTS OVER NORTHERN LYNN CANAL BY TOMORROW
AFTERNOON WITH 30 KT SMALL CRAFT WINDS OVER SOUTHERN LYNN AND 25
KT SMALL CRAFT WINDS OVER GLACIER BAY. VERY STRONG WINDS WILL BE
BLOWING OUT OF TAKU INLET AS WELL, AND SUSPECT THINGS WILL BE
GETTING PRETTY GUSTY NEAR DOWNTOWN JUNEAU BY THE END OF THE DAY
TOMORROW AS WELL.

PREFERRED A BLEND OF THE NAM WITH A LITTLE HELP FROM GEM FOR
PRESSURE AND WIND. POP AND QPF FROM ECMWF AND GFS. NO CHANGE TO
TEMPS. OVERALL CONFIDENCE IS AVERAGE.

.LONG TERM...UPPER RIDGE WILL BUILD NE INTO INTERIOR AK AND BECOME
A BLOCKY UPPER HIGH BY FRI NIGHT. THIS WILL BUILD SFC HIGH OVER
INTERIOR AK AND NW CANADA THRU SAT. THIS HIGH WILL EVENTUALLY SHIFT
TO THE E THEN SE THRU WRN CANADA NEXT WEEK AS UPPER HIGH SHIFTS SE
AND MERGES WITH RIDGE TO THE EAST OF THE AREA. WEAKENING OCCLUDED
FRONT WILL MOVE NWD AND AFFECT MAINLY THE SRN AREA SAT-SUN. LOOKS
LIKE STRONGER SYSTEMS WILL TRY TO MOVE IN NEXT WEEK...BUT MODEL
AGREEMENT DECREASES SO CONFIDENCE IN TIMING AND TRACK ARE FAIRLY LOW.
USED BLEND OF THE 12Z ECMWF/GEM/NAM FRI NIGHT-SAT NIGHT...THEN
EC/GEM BLEND FOR SUN...THEN WPC FOR MON ONWARD. BLENDED WPC WITH
THE EC/GEM BLEND SUN NIGHT TO SMOOTH THE TRANSITION.

COLDER AIR WILL FILTER INTO THE NRN AREA FRI NIGHT AND SAT...AND
REACH THE CENTRAL AREA SAT NIGHT. WINDS WILL INCREASE TO STORM
FORCE IN LYNN CANAL WITH GALES OVER MUCH OF THE REMAINING NRN
CHANNELS FRI NIGHT AND SAT. WILL HAVE STRONG OUTFLOW WINDS
DEVELOP...AND THERE IS POTENTIAL FOR MTN WAVE ACTIVITY IN THE
DOWNTOWN JUNEAU AREA FRI NIGHT-SUN. OCCLUDED FRONT MOVING NWD WILL
LIKELY SPREAD SOME PRECIP INTO THE SRN AREA FOR SAT NIGHT AND
SUN...BUT WILL SHEAR APART AS IT TRIES TO GET FURTHER N DUE TO THE
STRONG BLOCKY HIGH.

WILL SEE MODERATING TREND IN TEMPS BY MIDWEEK. AS MENTIONED
BEFORE...ONE OR MORE SYSTEMS WILL LIKELY MOVE INTO THE AREA BUT
HAVE LOW CONFIDENCE IN TRACK/TIMING. WILL HAVE GRADUALLY
INCREASING POPS FOR TUE-THU. LOOKS LIKE BY TIME ANY SIGNIFICANT
PRECIP WOULD GET IN...IT WILL WARM ENOUGH FOR THE PRECIP TO BE
MOSTLY RAIN...ESPECIALLY BY WED NIGHT-THU.

&&

.AJK WATCHES/WARNINGS/ADVISORIES...
PUBLIC...NONE.
MARINE...GALE WARNING FOR PKZ012.
         SMALL CRAFT ADVISORY FOR PKZ011-013-031.
         SMALL CRAFT ADVISORY DUE TO SEAS FOR PKZ041>043-051-052.

&&

$$

FRITSCH/RWT

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







000
FXAK67 PAJK 300054
AFDAJK

SOUTHEAST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE JUNEAU AK
354 PM AKST THU JAN 29 2015

.SHORT TERM...SOME COLDER AIR REMAINS IN PLACE AND THE ARCTIC
FRONT HAS REMAINED AS FAR SOUTH AS THE AUKE BAY AREA FOR A GOOD
PORTION OF THE DAY TODAY. SNOW SHOWERS AT THE BACK OF THE
MENDENHALL VALLEY TOTALED MORE THAN 1/2 INCH BEFORE FINALLY
WARMING UP ABOVE FREEZING. FARTHER NORTH, HEAVY SNOW CONTINUED TO
FALL AT THE KENSINGTON MINE INTO THE AFTERNOON. THE FRONTAL
FEATURE THAT RESULTED IN HEAVY SNOW IN HAINES AND SKAGWAY
OVERNIGHT IS WEAKENING AS IT CONTINUES TO SLOWLY MOVE NORTH.
SCATTERED RAIN AND SNOW SHOWERS WILL CONTINUE THROUGH THE EVENING
AND THEN DIMINISH TO AN END OVERNIGHT FOR THE NORTHERN ZONES WITH
SCATTERED SHOWER ACTIVITY IN THE YAKUTAT AREA CONTINUING THROUGH
THE NIGHT. MORE SOUTHERLY LOCATIONS HAVE BEEN DRY FOR THE MOST PART
SINCE LATE MORNING.

THERE HAVE BEEN SOME BREAKS IN THE CLOUD COVER TODAY...PRIMARILY OVER
THE SOUTHERN PANHANDLE...AND MORE BREAKS WILL SHOW UP FARTHER
NORTH. ENOUGH SO THAT FOG HAS BEEN INCLUDED IN SOME OF THE
PANHANDLE TAF SITES. WHATEVER FOG DOES FORM SHOULD DISPERSE
QUICKLY TOMORROW WITH THE FIRST LIGHT WINDS OF THE DAY.

WINDS AND SEAS NOT MUCH OF A FACTOR THROUGH TONIGHT. A LONG PERIOD
(8 TO 10 SECONDS) 8 FOOT SWELL DOMINATES MOST OF THE OUTER COAST,
BUT VERY LITTLE IN THE WAY OF WIND WAVE. AN OFFSHORE GRADIENT WILL
INTENSIFY TOMORROW OVER THE FAR NORTHERN INNER CHANNELS. LOOK FOR
NORTHERLY GALES TO 40 KTS OVER NORTHERN LYNN CANAL BY TOMORROW
AFTERNOON WITH 30 KT SMALL CRAFT WINDS OVER SOUTHERN LYNN AND 25
KT SMALL CRAFT WINDS OVER GLACIER BAY. VERY STRONG WINDS WILL BE
BLOWING OUT OF TAKU INLET AS WELL, AND SUSPECT THINGS WILL BE
GETTING PRETTY GUSTY NEAR DOWNTOWN JUNEAU BY THE END OF THE DAY
TOMORROW AS WELL.

PREFERRED A BLEND OF THE NAM WITH A LITTLE HELP FROM GEM FOR
PRESSURE AND WIND. POP AND QPF FROM ECMWF AND GFS. NO CHANGE TO
TEMPS. OVERALL CONFIDENCE IS AVERAGE.

.LONG TERM...UPPER RIDGE WILL BUILD NE INTO INTERIOR AK AND BECOME
A BLOCKY UPPER HIGH BY FRI NIGHT. THIS WILL BUILD SFC HIGH OVER
INTERIOR AK AND NW CANADA THRU SAT. THIS HIGH WILL EVENTUALLY SHIFT
TO THE E THEN SE THRU WRN CANADA NEXT WEEK AS UPPER HIGH SHIFTS SE
AND MERGES WITH RIDGE TO THE EAST OF THE AREA. WEAKENING OCCLUDED
FRONT WILL MOVE NWD AND AFFECT MAINLY THE SRN AREA SAT-SUN. LOOKS
LIKE STRONGER SYSTEMS WILL TRY TO MOVE IN NEXT WEEK...BUT MODEL
AGREEMENT DECREASES SO CONFIDENCE IN TIMING AND TRACK ARE FAIRLY LOW.
USED BLEND OF THE 12Z ECMWF/GEM/NAM FRI NIGHT-SAT NIGHT...THEN
EC/GEM BLEND FOR SUN...THEN WPC FOR MON ONWARD. BLENDED WPC WITH
THE EC/GEM BLEND SUN NIGHT TO SMOOTH THE TRANSITION.

COLDER AIR WILL FILTER INTO THE NRN AREA FRI NIGHT AND SAT...AND
REACH THE CENTRAL AREA SAT NIGHT. WINDS WILL INCREASE TO STORM
FORCE IN LYNN CANAL WITH GALES OVER MUCH OF THE REMAINING NRN
CHANNELS FRI NIGHT AND SAT. WILL HAVE STRONG OUTFLOW WINDS
DEVELOP...AND THERE IS POTENTIAL FOR MTN WAVE ACTIVITY IN THE
DOWNTOWN JUNEAU AREA FRI NIGHT-SUN. OCCLUDED FRONT MOVING NWD WILL
LIKELY SPREAD SOME PRECIP INTO THE SRN AREA FOR SAT NIGHT AND
SUN...BUT WILL SHEAR APART AS IT TRIES TO GET FURTHER N DUE TO THE
STRONG BLOCKY HIGH.

WILL SEE MODERATING TREND IN TEMPS BY MIDWEEK. AS MENTIONED
BEFORE...ONE OR MORE SYSTEMS WILL LIKELY MOVE INTO THE AREA BUT
HAVE LOW CONFIDENCE IN TRACK/TIMING. WILL HAVE GRADUALLY
INCREASING POPS FOR TUE-THU. LOOKS LIKE BY TIME ANY SIGNIFICANT
PRECIP WOULD GET IN...IT WILL WARM ENOUGH FOR THE PRECIP TO BE
MOSTLY RAIN...ESPECIALLY BY WED NIGHT-THU.

&&

.AJK WATCHES/WARNINGS/ADVISORIES...
PUBLIC...NONE.
MARINE...GALE WARNING FOR PKZ012.
         SMALL CRAFT ADVISORY FOR PKZ011-013-031.
         SMALL CRAFT ADVISORY DUE TO SEAS FOR PKZ041>043-051-052.

&&

$$

FRITSCH/RWT

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








000
FXAK67 PAJK 291441
AFDAJK

SOUTHEAST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE JUNEAU AK
541 AM AKST THU JAN 29 2015

.SHORT TERM...MORNING SURFACE OBSERVATIONS SHOW A FRONTAL BOUNDARY
EXTENDING EWD FROM THE NRN GULF TOWARD AN AREA BETWEEN SITKA AND
JUNEAU. IN ADDITION...IR IMAGERY REVEALS COOLING CLOUD TOPS ALONG
AND N OF THE BOUNDARY...WHICH CORRESPONDS TO A BLOSSOMING ZONE OF
PRECIPITATION THAT WILL IMPACT NRN PORTIONS OF THE CWA THROUGH THE
AFTERNOON. THE BOUNDARY IS FORECAST TO DRIFT SLIGHTLY N DURING THE
MORNING/AFTERNOON BEFORE DISSIPATING...WHICH WILL FAVOR A MODEST
RISE IN TEMPERATURES FROM YAKUTAT TO JUNEAU AND POINTS NWD. THIS
WILL MAKE A TRANSITION TO RAIN INCREASINGLY LIKELY FOR SEA LEVEL
LOCATIONS CURRENTLY EXPERIENCING SNOW. MEANWHILE...SNOW OCCURRING
AT WHITE PASS AND AREAS NEAR HAINES CUSTOMS WILL DIMINISH IN
INTENSITY DURING THE MORNING. THUS...THE WINTER WEATHER ADVISORY
AND WARNING ARE ON TRACK FOR A NOON CANCELLATION...IF NOT SOONER.

OVER THE SRN PANHANDLE...RAIN IS FORECAST TO DISSIPATE BY MIDDAY
AS A DEEP-LAYER OF DRY AIR SPREADS NEWD FROM THE NERN PAC. DRYING
WILL CONTINUE INTO TONIGHT AND SPREAD N INTO THE CNTRL PANHANDLE
AS UPPER-LEVEL SUBSIDENCE INCREASES N OF A WEAK DISTURBANCE
APPROACHING HAIDA GWAII. CLEARING SKIES AND A MOIST BOUNDARY LAYER
MAY AID IN PATCHY FOG DEVELOPMENT FROM PETERSBURG TO ANGOON.
ELSEWHERE...STEEPENING LAPSE RATES AND MODEST ASCENT WILL FAVOR
SHOWERS TONIGHT FROM YAKUTAT TO GUSTAVUS AND HAINES.

AS THE FRONTAL BOUNDARY WAVERS NWD THROUGH THIS AFTERNOON...THE
SURFACE PRESSURE GRADIENT WILL SLACKEN FOR SKAGWAY AND LYNN
CANAL...RESULTING IN WINDS WEAKENING TO AROUND 10 KT AND
OCCASIONALLY BECOMING VARIABLE IN DIRECTION. UPPER-LEVEL
SUBSIDENCE WILL ALSO SUPPORT A WEAK RIDGE OF HIGH PRESSURE
DEVELOPING OVER THE CNTRL PANHANDLE INTO THE ERN GULF FAVORING
WINDS GENERALLY AOB 15 KT FOR MANY OF THE INNER CHANNELS AND
ADJACENT OUTSIDE WATERS. BY LATE TONIGHT...THE PRESSURE GRADIENT
IS FORECAST TO TIGHTEN BACK UP OVER NRN LYNN CANAL SUPPORTING AN
INCREASE IN NLY WINDS TO 20 KT. PRESSURE GRADIENT WILL ALSO
TIGHTEN OVER CLARENCE STRAIT AS A LOW MOVES TOWARD HAIDA
GWAII...WITH 20 KT NLYS ANTICIPATED.

NO CHANGE WAS MADE TO INHERITED PRESSURE GRIDS. POP AND QPF WERE
MODIFIED WITH ECMWF AND HI-RES ARW/NMM. BIGGEST CHANGE TO THESE
FIELDS WAS A REDUCTION IN BOTH OVER THE SRN PANHANDLE TONIGHT.

.LONG TERM...UPPER LEVEL CUT OFF LOW OVER THE NORTHERN PACIFIC
SOUTH OF THE ALASKA PENINSULA, AND THE JET STREAM PASSING THROUGH
THE ALASKA INTERIOR WILL BE THE MAIN PLAYERS IN THE LONG RANGE
FORECAST FOR THE NEXT WEEK. BOTH FEATURES WILL LARGELY REMAIN
UNCHANGED AS FAR AS POSITION BUT THE VARIOUS SMALL WAVES AND
PULSES THAT RIDE ALONG THESE FEATURES AND THEIR INTERACTIONS WITH
EACH OTHER WILL PROVIDE THE FLUCTUATIONS THAT WILL BE SEEN IN THE
FORECAST.

THE FIRST MAJOR SHIFT SHOWS UP FRI INTO SAT AS A TROUGH ALONG THE
JET BRINGS IN SOME COLD AIR INTO THE SOUTHERN YUKON. SURFACE
PRESSURES ARE EXPECTED TO HIT 1045 MB BY FRI NIGHT ACROSS THE
SOUTHERN YUKON WITH PRESSURE GRADIENTS ALONG THE COAST MOUNTAINS
REACHING 10 TO 15 MB. OUTFLOW WINDS WILL BE BLOWING THROUGH MANY
MOUNTAIN PASSES WITH STORM FORCE WINDS EXPECTED SAT IN LYNN CANAL
AND STRONG WIND GUSTS IN SKAGWAY, HAINES, THE PASSES EAST OF
YAKUTAT, DISENCHANTMENT BAY, AND TAKU INLET. MOUNTAIN WAVE WINDS
IN DOWNTOWN JUNEAU AND DOUGLAS ARE A GOOD POSSIBILITY AS WELL WITH CROSS
BARRIER FLOW INCREASING TO 40 TO 50 KT. AN INVERSION ABOVE RIDGE
TOP IS ALSO EXPECTED WITH THE COLD AIR OUTFLOW. THE CRUCIAL LEVEL
MIGHT BE THE LIMITING FACTOR AS WHILE THERE IS A DEFINITE WIND
SHIFT IT IS ONLY AT AROUND 600 TO 700 MB RATHER THEN THE IDEAL
500 MB. STILL GUSTS TO 50 MPH ARE EXPECTED FOR DOWNTOWN JUNEAU AND
DOUGLAS LATE FRI NIGHT THROUGH SAT NIGHT.

MEANWHILE THE SOUTHERN PANHANDLE WILL BE DEALING WITH WHAT THE CUT
OFF UPPER LOW HAS TO THROW AT US. IT COMES IN THE FORM OF A
WEAKENING FRONT OVER THE WEEKEND. WINDS OUT IN THE GULF WILL BE
INCREASING TO GALE FORCE ON FRI NIGHT AND SAT AS A RESULT BUT WILL
BE GRADUALLY DIMINISHING AS THE FRONT SHEARS APART UNDER DIFLUENT
FLOW. THE PRECIP SHIELD WILL ALSO NOT MAKE IT THAT FAR NORTH AS A
RESULT OF THE SAME DIFLUENT FLOW AND THE DRY NORTHERLY OUTFLOW
FARTHER NORTH. LIKELY POPS ONLY MAKE IT AS FAR NORTH AS FREDERICK
SOUND AT MOST AND EVEN THEN EXPECTED AMOUNTS WILL BE LIGHT AS THE
FRONT SHEARS APART.

THE COLD AIR LOOKS TO BE IN A LOSING BATTLE WITH THE WARM AIR BY
EARLY NEXT WEEK AS THE MAIN PUSH OF COLD AIR MOVES OFF TO THE
EAST. NEW MODEL RUNS ARE INCREASING SOUTHERLY FLOW ACROSS THE AREA
INTO EARLY NEXT WEEK, BUT WITH FEW, IF ANY, STRONG STORMS COMING
IN THERE WILL BE VERY LITTLE TO KICK THE COLD AIR OUT OF THE INNER
CHANNELS. THUS TEMPERATURES WILL REMAIN COOL BUT NOT BITTERLY COLD
EARLY NEXT WEEK. NEXT MAJOR STORM LOOKS TO COMES MID TO LATE NEXT
WEEK AS MORE COLD AIR GETS INJECTED INTO THE WESTERN HALF OF THE
UPPER LOW THOUGH MODELS ARE GETTING REALLY SPREAD OUT AT THIS
POINT.

OVERALL MODELS WERE IN DECENT AGREEMENT WITH MOST FEATURES THROUGH
EARLY NEXT WEEK DECENTLY REPRESENTED. NOT MANY CHANGES OVERALL AS
MODELS KEPT THE MAIN IDEA OVER THE LAST 24 HOURS. THROUGH DID
SPEED UP THE FRONT OVER THE SOUTHERN GULF OVER THE WEEKEND. MAIN
GUIDANCE USED WAS NAM/EC/GEM FOR MOST OF THE PERIOD.

&&

.AJK WATCHES/WARNINGS/ADVISORIES...
PUBLIC...WINTER STORM WARNING UNTIL NOON AKST TODAY FOR AKZ019.
         WINTER WEATHER ADVISORY UNTIL NOON AKST TODAY FOR AKZ018.
MARINE...SMALL CRAFT ADVISORY FOR PKZ036-051.
         SMALL CRAFT ADVISORY DUE TO SEAS FOR PKZ041>043-052.

&&

$$

GARNER/EAL

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












000
FXAK67 PAJK 291441
AFDAJK

SOUTHEAST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE JUNEAU AK
541 AM AKST THU JAN 29 2015

.SHORT TERM...MORNING SURFACE OBSERVATIONS SHOW A FRONTAL BOUNDARY
EXTENDING EWD FROM THE NRN GULF TOWARD AN AREA BETWEEN SITKA AND
JUNEAU. IN ADDITION...IR IMAGERY REVEALS COOLING CLOUD TOPS ALONG
AND N OF THE BOUNDARY...WHICH CORRESPONDS TO A BLOSSOMING ZONE OF
PRECIPITATION THAT WILL IMPACT NRN PORTIONS OF THE CWA THROUGH THE
AFTERNOON. THE BOUNDARY IS FORECAST TO DRIFT SLIGHTLY N DURING THE
MORNING/AFTERNOON BEFORE DISSIPATING...WHICH WILL FAVOR A MODEST
RISE IN TEMPERATURES FROM YAKUTAT TO JUNEAU AND POINTS NWD. THIS
WILL MAKE A TRANSITION TO RAIN INCREASINGLY LIKELY FOR SEA LEVEL
LOCATIONS CURRENTLY EXPERIENCING SNOW. MEANWHILE...SNOW OCCURRING
AT WHITE PASS AND AREAS NEAR HAINES CUSTOMS WILL DIMINISH IN
INTENSITY DURING THE MORNING. THUS...THE WINTER WEATHER ADVISORY
AND WARNING ARE ON TRACK FOR A NOON CANCELLATION...IF NOT SOONER.

OVER THE SRN PANHANDLE...RAIN IS FORECAST TO DISSIPATE BY MIDDAY
AS A DEEP-LAYER OF DRY AIR SPREADS NEWD FROM THE NERN PAC. DRYING
WILL CONTINUE INTO TONIGHT AND SPREAD N INTO THE CNTRL PANHANDLE
AS UPPER-LEVEL SUBSIDENCE INCREASES N OF A WEAK DISTURBANCE
APPROACHING HAIDA GWAII. CLEARING SKIES AND A MOIST BOUNDARY LAYER
MAY AID IN PATCHY FOG DEVELOPMENT FROM PETERSBURG TO ANGOON.
ELSEWHERE...STEEPENING LAPSE RATES AND MODEST ASCENT WILL FAVOR
SHOWERS TONIGHT FROM YAKUTAT TO GUSTAVUS AND HAINES.

AS THE FRONTAL BOUNDARY WAVERS NWD THROUGH THIS AFTERNOON...THE
SURFACE PRESSURE GRADIENT WILL SLACKEN FOR SKAGWAY AND LYNN
CANAL...RESULTING IN WINDS WEAKENING TO AROUND 10 KT AND
OCCASIONALLY BECOMING VARIABLE IN DIRECTION. UPPER-LEVEL
SUBSIDENCE WILL ALSO SUPPORT A WEAK RIDGE OF HIGH PRESSURE
DEVELOPING OVER THE CNTRL PANHANDLE INTO THE ERN GULF FAVORING
WINDS GENERALLY AOB 15 KT FOR MANY OF THE INNER CHANNELS AND
ADJACENT OUTSIDE WATERS. BY LATE TONIGHT...THE PRESSURE GRADIENT
IS FORECAST TO TIGHTEN BACK UP OVER NRN LYNN CANAL SUPPORTING AN
INCREASE IN NLY WINDS TO 20 KT. PRESSURE GRADIENT WILL ALSO
TIGHTEN OVER CLARENCE STRAIT AS A LOW MOVES TOWARD HAIDA
GWAII...WITH 20 KT NLYS ANTICIPATED.

NO CHANGE WAS MADE TO INHERITED PRESSURE GRIDS. POP AND QPF WERE
MODIFIED WITH ECMWF AND HI-RES ARW/NMM. BIGGEST CHANGE TO THESE
FIELDS WAS A REDUCTION IN BOTH OVER THE SRN PANHANDLE TONIGHT.

.LONG TERM...UPPER LEVEL CUT OFF LOW OVER THE NORTHERN PACIFIC
SOUTH OF THE ALASKA PENINSULA, AND THE JET STREAM PASSING THROUGH
THE ALASKA INTERIOR WILL BE THE MAIN PLAYERS IN THE LONG RANGE
FORECAST FOR THE NEXT WEEK. BOTH FEATURES WILL LARGELY REMAIN
UNCHANGED AS FAR AS POSITION BUT THE VARIOUS SMALL WAVES AND
PULSES THAT RIDE ALONG THESE FEATURES AND THEIR INTERACTIONS WITH
EACH OTHER WILL PROVIDE THE FLUCTUATIONS THAT WILL BE SEEN IN THE
FORECAST.

THE FIRST MAJOR SHIFT SHOWS UP FRI INTO SAT AS A TROUGH ALONG THE
JET BRINGS IN SOME COLD AIR INTO THE SOUTHERN YUKON. SURFACE
PRESSURES ARE EXPECTED TO HIT 1045 MB BY FRI NIGHT ACROSS THE
SOUTHERN YUKON WITH PRESSURE GRADIENTS ALONG THE COAST MOUNTAINS
REACHING 10 TO 15 MB. OUTFLOW WINDS WILL BE BLOWING THROUGH MANY
MOUNTAIN PASSES WITH STORM FORCE WINDS EXPECTED SAT IN LYNN CANAL
AND STRONG WIND GUSTS IN SKAGWAY, HAINES, THE PASSES EAST OF
YAKUTAT, DISENCHANTMENT BAY, AND TAKU INLET. MOUNTAIN WAVE WINDS
IN DOWNTOWN JUNEAU AND DOUGLAS ARE A GOOD POSSIBILITY AS WELL WITH CROSS
BARRIER FLOW INCREASING TO 40 TO 50 KT. AN INVERSION ABOVE RIDGE
TOP IS ALSO EXPECTED WITH THE COLD AIR OUTFLOW. THE CRUCIAL LEVEL
MIGHT BE THE LIMITING FACTOR AS WHILE THERE IS A DEFINITE WIND
SHIFT IT IS ONLY AT AROUND 600 TO 700 MB RATHER THEN THE IDEAL
500 MB. STILL GUSTS TO 50 MPH ARE EXPECTED FOR DOWNTOWN JUNEAU AND
DOUGLAS LATE FRI NIGHT THROUGH SAT NIGHT.

MEANWHILE THE SOUTHERN PANHANDLE WILL BE DEALING WITH WHAT THE CUT
OFF UPPER LOW HAS TO THROW AT US. IT COMES IN THE FORM OF A
WEAKENING FRONT OVER THE WEEKEND. WINDS OUT IN THE GULF WILL BE
INCREASING TO GALE FORCE ON FRI NIGHT AND SAT AS A RESULT BUT WILL
BE GRADUALLY DIMINISHING AS THE FRONT SHEARS APART UNDER DIFLUENT
FLOW. THE PRECIP SHIELD WILL ALSO NOT MAKE IT THAT FAR NORTH AS A
RESULT OF THE SAME DIFLUENT FLOW AND THE DRY NORTHERLY OUTFLOW
FARTHER NORTH. LIKELY POPS ONLY MAKE IT AS FAR NORTH AS FREDERICK
SOUND AT MOST AND EVEN THEN EXPECTED AMOUNTS WILL BE LIGHT AS THE
FRONT SHEARS APART.

THE COLD AIR LOOKS TO BE IN A LOSING BATTLE WITH THE WARM AIR BY
EARLY NEXT WEEK AS THE MAIN PUSH OF COLD AIR MOVES OFF TO THE
EAST. NEW MODEL RUNS ARE INCREASING SOUTHERLY FLOW ACROSS THE AREA
INTO EARLY NEXT WEEK, BUT WITH FEW, IF ANY, STRONG STORMS COMING
IN THERE WILL BE VERY LITTLE TO KICK THE COLD AIR OUT OF THE INNER
CHANNELS. THUS TEMPERATURES WILL REMAIN COOL BUT NOT BITTERLY COLD
EARLY NEXT WEEK. NEXT MAJOR STORM LOOKS TO COMES MID TO LATE NEXT
WEEK AS MORE COLD AIR GETS INJECTED INTO THE WESTERN HALF OF THE
UPPER LOW THOUGH MODELS ARE GETTING REALLY SPREAD OUT AT THIS
POINT.

OVERALL MODELS WERE IN DECENT AGREEMENT WITH MOST FEATURES THROUGH
EARLY NEXT WEEK DECENTLY REPRESENTED. NOT MANY CHANGES OVERALL AS
MODELS KEPT THE MAIN IDEA OVER THE LAST 24 HOURS. THROUGH DID
SPEED UP THE FRONT OVER THE SOUTHERN GULF OVER THE WEEKEND. MAIN
GUIDANCE USED WAS NAM/EC/GEM FOR MOST OF THE PERIOD.

&&

.AJK WATCHES/WARNINGS/ADVISORIES...
PUBLIC...WINTER STORM WARNING UNTIL NOON AKST TODAY FOR AKZ019.
         WINTER WEATHER ADVISORY UNTIL NOON AKST TODAY FOR AKZ018.
MARINE...SMALL CRAFT ADVISORY FOR PKZ036-051.
         SMALL CRAFT ADVISORY DUE TO SEAS FOR PKZ041>043-052.

&&

$$

GARNER/EAL

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











000
FXAK67 PAJK 290032
AFDAJK

SOUTHEAST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE JUNEAU AK
332 PM AKST WED JAN 28 2015

.SHORT TERM...COLD AIR HAS REMAINED IN PLACE THROUGH THE DAY SUCH
THAT THOSE LOCATIONS WHICH WOKE UP TO SNOW THIS MORNING ARE STILL
SEEING SNOW. VERY LITTLE CHANGE TO TEMPERATURES EXPECTED
OVERNIGHT AND PLENTY OF MOISTURE STREAMING IN FROM THE SOUTH, SO
MORE SNOW IS FORECAST OVERNIGHT. HAVE ISSUED A WINTER STORM WARNING
FOR HAINES, AND HAVE WINTER WEATHER ADVISORIES FOR GUSTAVUS,
SKAGWAY, AND HAINES. A VERY MODEST INCREASE IN TEMPS OVERNIGHT IN
THE JUNEAU AREA IS POSSIBLE AND TEMPS ARE MOST LIKELY GOING TO
RISE ABOVE FREEZING TOMORROW, SO THAT ADVISORY WILL END FIRST AT
6AM.

SATELLITE IMAGERY IS SHOWING A FRONT ORIENTED NORTH-SOUTH AND
MOVING NNE OVER THE PANHANDLE. WATER VAPOR IMAGERY ALSO REVEALING
A BROAD AND SOLID CONNECTION TO LOW LATITUDE MOISTURE SOURCE. TPW
VALUES FAIRLY MODEST AT AROUND 1 INCH BUT WITH THE TRAINING MOTION
OVER SOUTHEAST ALASKA, THE NET EFFECT WILL BE MUCH MORE INTENSE.
RADAR DATA THROUGH THE DAY CONFIRMING THIS WITH UPWARDS OF 60 DBZ
TOTAL REFLECTIVITY BEING OBSERVED. 500MB DEFORMATION AND TEMPS
INDICATING AT LEAST ONE FRONTOGENETIC BAND IS MOVING NORTH ACROSS
THE PANHANDLE TODAY. ALL THIS ADDS UP TO A SIGNIFICANT INCREASE TO
THE SNOW TOTALS IN THE SHORT RANGE FORECAST ISSUED THIS AFTERNOON.

THINK THE RAIN-SNOW LINE WILL REMAIN SOMEWHERE BETWEEN ANGOON AND
ICY STRAIT FOR MOST OF THE NIGHT, SO HAVE RAIN FOR MOST OF THE
SOUTHERN PANHANDLE. RAIN HEAVY AT TIMES FOR THE FAR SOUTHERN
PORTION OF THE PANHANDLE. COORDINATED WITH ENVIRONMENT CANADA
REGARDING THE AREA AROUND HYDER AND STEWART WITH A RAIN-SNOW MIX
FOR BOTH TONIGHT AND TOMORROW MORNING. NOT ANTICIPATING MORE THAN
1 INCH THERE.

BLENDED NAM, GFS, AND GEM FOR UPDATES TO PRESSURE WITH THE GEM
BEING USED TO MORE CLEARLY CAPTURE A WAVE DEVELOPING INTO A SURFACE
LOW ALONG THE FRONTAL BOUNDARY. POP AND QPF PRIMARILY FROM NAM
WITH A LITTLE HELP FROM GFS. TEMPS PRIMARILY PER GFS MOS. OVERALL
FORECAST CONFIDENCE IS AVERAGE.

.LONG TERM...MODELS BEGINNING TO SHOW INCREASING THREAT FOR PRECIP
TO THE SRN AREA LATER THU NIGHT/FRI. GEM/EC/NAM ALL SHOW A LOW
MOVING NE TOWARD THE FAR SERN AREA...WITH SOME DIFFS IN EXACT
TRACK AND STRENGTH BETWEEN THE MODELS. USED BLEND OF THE 12Z GEM/EC/NAM
TO HANDLE THIS SYSTEM. POPS RAISED TO LIKELY BY EARLY FRI FOR THE
FAR SRN ZONES...WITH CHANCE POPS FOR THE S-CENTRAL AREA. ALSO
DRIED THINGS OUT SOME OVER THE NRN AREAS DUE TO THIS SYSTEM
TURNING FLOW OFFSHORE QUICKER. COLDER AIR SHOULD PUSH IN FROM THE
N ONCE SYSTEM MOVES OUT OF THE AREA FRI NIGHT AND SAT.

FOR THE WEEKEND AND BEYOND...ENDED UP MAINTAINING THE GEM/EC/NAM BLEND
THRU SAT...THEN WENT WITH LATEST WPC FROM SUN ONWARD. BLENDED WPC
WITH THE GEM/EC FOR SAT NIGHT. STRONG HIGH PRESSURE WILL BUILD
OVER INTERIOR AK AND NW CANADA. LOOKING LIKE A FRONT WILL TRY TO
MOVE NWD INTO THE AREA FOR THE SAT NIGHT-SUN PERIOD...BUT IT WILL
RUN INTO THE COLDER AND DRIER AIR MOVING SWD. THINK BEST THREAT
FOR PRECIP WILL BE OVER THE SRN HALF OF THE AREA WITH THIS SYSTEM.
LOOKS LIKE THE ARCTIC HIGH WILL FINALLY SLIDE OFF TO THE SE EARLY
NEXT WEEK WITH MORE SYSTEMS COMING TOWARD THE AREA FROM THE
SW...SO LOOKS LIKE INCREASING PRECIP THREAT AND MODERATION OF
TEMPS WILL OCCUR. SIGNIFICANT MODEL DIFFERENCES WHERE THE
SHORTWAVE ENERGY GOES HOWEVER...SO CONFIDENCE IN EXACT TIMING/TRACK
OF SYSTEMS NEXT WEEK IS BELOW AVERAGE.

&&

.AVIATION...MAIN IMPACTS TO AVIATION ACTIVITIES WILL BE REDUCED
VISIBILITIES IN SNOW. WIDESPREAD CEILINGS BELOW MOST PANHANDLE
MOUNTAINTOPS. AND ICING, MOSTLY RIME, HAS BEEN REPORTED BELOW FL100 IN
PIREPS TODAY. AM FULLY EXPECTING THOSE CONDITIONS TO CONTINUE
THROUGH TOMORROW AFTERNOON. SEE AAWU AIRMETS ZULU AND SIERRA AS
WELL AS THE APPLICABLE FA FOR ADDITIONAL INFORMATION.

&&

.AJK WATCHES/WARNINGS/ADVISORIES...
PUBLIC...WINTER WEATHER ADVISORY UNTIL 6 AM AKST THURSDAY FOR AKZ025.
         WINTER STORM WARNING UNTIL NOON AKST THURSDAY FOR AKZ019.
         WINTER WEATHER ADVISORY UNTIL NOON AKST THURSDAY FOR AKZ018-020.
         STRONG WIND UNTIL 4 PM AKST THIS AFTERNOON FOR AKZ018.
MARINE...GALE WARNING FOR PKZ022-036-041.
         SMALL CRAFT ADVISORY FOR PKZ011>013-021-031>035-042-043-051-052.

&&

$$

FRITSCH/RWT

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











000
FXAK67 PAJK 290032
AFDAJK

SOUTHEAST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE JUNEAU AK
332 PM AKST WED JAN 28 2015

.SHORT TERM...COLD AIR HAS REMAINED IN PLACE THROUGH THE DAY SUCH
THAT THOSE LOCATIONS WHICH WOKE UP TO SNOW THIS MORNING ARE STILL
SEEING SNOW. VERY LITTLE CHANGE TO TEMPERATURES EXPECTED
OVERNIGHT AND PLENTY OF MOISTURE STREAMING IN FROM THE SOUTH, SO
MORE SNOW IS FORECAST OVERNIGHT. HAVE ISSUED A WINTER STORM WARNING
FOR HAINES, AND HAVE WINTER WEATHER ADVISORIES FOR GUSTAVUS,
SKAGWAY, AND HAINES. A VERY MODEST INCREASE IN TEMPS OVERNIGHT IN
THE JUNEAU AREA IS POSSIBLE AND TEMPS ARE MOST LIKELY GOING TO
RISE ABOVE FREEZING TOMORROW, SO THAT ADVISORY WILL END FIRST AT
6AM.

SATELLITE IMAGERY IS SHOWING A FRONT ORIENTED NORTH-SOUTH AND
MOVING NNE OVER THE PANHANDLE. WATER VAPOR IMAGERY ALSO REVEALING
A BROAD AND SOLID CONNECTION TO LOW LATITUDE MOISTURE SOURCE. TPW
VALUES FAIRLY MODEST AT AROUND 1 INCH BUT WITH THE TRAINING MOTION
OVER SOUTHEAST ALASKA, THE NET EFFECT WILL BE MUCH MORE INTENSE.
RADAR DATA THROUGH THE DAY CONFIRMING THIS WITH UPWARDS OF 60 DBZ
TOTAL REFLECTIVITY BEING OBSERVED. 500MB DEFORMATION AND TEMPS
INDICATING AT LEAST ONE FRONTOGENETIC BAND IS MOVING NORTH ACROSS
THE PANHANDLE TODAY. ALL THIS ADDS UP TO A SIGNIFICANT INCREASE TO
THE SNOW TOTALS IN THE SHORT RANGE FORECAST ISSUED THIS AFTERNOON.

THINK THE RAIN-SNOW LINE WILL REMAIN SOMEWHERE BETWEEN ANGOON AND
ICY STRAIT FOR MOST OF THE NIGHT, SO HAVE RAIN FOR MOST OF THE
SOUTHERN PANHANDLE. RAIN HEAVY AT TIMES FOR THE FAR SOUTHERN
PORTION OF THE PANHANDLE. COORDINATED WITH ENVIRONMENT CANADA
REGARDING THE AREA AROUND HYDER AND STEWART WITH A RAIN-SNOW MIX
FOR BOTH TONIGHT AND TOMORROW MORNING. NOT ANTICIPATING MORE THAN
1 INCH THERE.

BLENDED NAM, GFS, AND GEM FOR UPDATES TO PRESSURE WITH THE GEM
BEING USED TO MORE CLEARLY CAPTURE A WAVE DEVELOPING INTO A SURFACE
LOW ALONG THE FRONTAL BOUNDARY. POP AND QPF PRIMARILY FROM NAM
WITH A LITTLE HELP FROM GFS. TEMPS PRIMARILY PER GFS MOS. OVERALL
FORECAST CONFIDENCE IS AVERAGE.

.LONG TERM...MODELS BEGINNING TO SHOW INCREASING THREAT FOR PRECIP
TO THE SRN AREA LATER THU NIGHT/FRI. GEM/EC/NAM ALL SHOW A LOW
MOVING NE TOWARD THE FAR SERN AREA...WITH SOME DIFFS IN EXACT
TRACK AND STRENGTH BETWEEN THE MODELS. USED BLEND OF THE 12Z GEM/EC/NAM
TO HANDLE THIS SYSTEM. POPS RAISED TO LIKELY BY EARLY FRI FOR THE
FAR SRN ZONES...WITH CHANCE POPS FOR THE S-CENTRAL AREA. ALSO
DRIED THINGS OUT SOME OVER THE NRN AREAS DUE TO THIS SYSTEM
TURNING FLOW OFFSHORE QUICKER. COLDER AIR SHOULD PUSH IN FROM THE
N ONCE SYSTEM MOVES OUT OF THE AREA FRI NIGHT AND SAT.

FOR THE WEEKEND AND BEYOND...ENDED UP MAINTAINING THE GEM/EC/NAM BLEND
THRU SAT...THEN WENT WITH LATEST WPC FROM SUN ONWARD. BLENDED WPC
WITH THE GEM/EC FOR SAT NIGHT. STRONG HIGH PRESSURE WILL BUILD
OVER INTERIOR AK AND NW CANADA. LOOKING LIKE A FRONT WILL TRY TO
MOVE NWD INTO THE AREA FOR THE SAT NIGHT-SUN PERIOD...BUT IT WILL
RUN INTO THE COLDER AND DRIER AIR MOVING SWD. THINK BEST THREAT
FOR PRECIP WILL BE OVER THE SRN HALF OF THE AREA WITH THIS SYSTEM.
LOOKS LIKE THE ARCTIC HIGH WILL FINALLY SLIDE OFF TO THE SE EARLY
NEXT WEEK WITH MORE SYSTEMS COMING TOWARD THE AREA FROM THE
SW...SO LOOKS LIKE INCREASING PRECIP THREAT AND MODERATION OF
TEMPS WILL OCCUR. SIGNIFICANT MODEL DIFFERENCES WHERE THE
SHORTWAVE ENERGY GOES HOWEVER...SO CONFIDENCE IN EXACT TIMING/TRACK
OF SYSTEMS NEXT WEEK IS BELOW AVERAGE.

&&

.AVIATION...MAIN IMPACTS TO AVIATION ACTIVITIES WILL BE REDUCED
VISIBILITIES IN SNOW. WIDESPREAD CEILINGS BELOW MOST PANHANDLE
MOUNTAINTOPS. AND ICING, MOSTLY RIME, HAS BEEN REPORTED BELOW FL100 IN
PIREPS TODAY. AM FULLY EXPECTING THOSE CONDITIONS TO CONTINUE
THROUGH TOMORROW AFTERNOON. SEE AAWU AIRMETS ZULU AND SIERRA AS
WELL AS THE APPLICABLE FA FOR ADDITIONAL INFORMATION.

&&

.AJK WATCHES/WARNINGS/ADVISORIES...
PUBLIC...WINTER WEATHER ADVISORY UNTIL 6 AM AKST THURSDAY FOR AKZ025.
         WINTER STORM WARNING UNTIL NOON AKST THURSDAY FOR AKZ019.
         WINTER WEATHER ADVISORY UNTIL NOON AKST THURSDAY FOR AKZ018-020.
         STRONG WIND UNTIL 4 PM AKST THIS AFTERNOON FOR AKZ018.
MARINE...GALE WARNING FOR PKZ022-036-041.
         SMALL CRAFT ADVISORY FOR PKZ011>013-021-031>035-042-043-051-052.

&&

$$

FRITSCH/RWT

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










000
FXAK67 PAJK 290032
AFDAJK

SOUTHEAST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE JUNEAU AK
332 PM AKST WED JAN 28 2015

.SHORT TERM...COLD AIR HAS REMAINED IN PLACE THROUGH THE DAY SUCH
THAT THOSE LOCATIONS WHICH WOKE UP TO SNOW THIS MORNING ARE STILL
SEEING SNOW. VERY LITTLE CHANGE TO TEMPERATURES EXPECTED
OVERNIGHT AND PLENTY OF MOISTURE STREAMING IN FROM THE SOUTH, SO
MORE SNOW IS FORECAST OVERNIGHT. HAVE ISSUED A WINTER STORM WARNING
FOR HAINES, AND HAVE WINTER WEATHER ADVISORIES FOR GUSTAVUS,
SKAGWAY, AND HAINES. A VERY MODEST INCREASE IN TEMPS OVERNIGHT IN
THE JUNEAU AREA IS POSSIBLE AND TEMPS ARE MOST LIKELY GOING TO
RISE ABOVE FREEZING TOMORROW, SO THAT ADVISORY WILL END FIRST AT
6AM.

SATELLITE IMAGERY IS SHOWING A FRONT ORIENTED NORTH-SOUTH AND
MOVING NNE OVER THE PANHANDLE. WATER VAPOR IMAGERY ALSO REVEALING
A BROAD AND SOLID CONNECTION TO LOW LATITUDE MOISTURE SOURCE. TPW
VALUES FAIRLY MODEST AT AROUND 1 INCH BUT WITH THE TRAINING MOTION
OVER SOUTHEAST ALASKA, THE NET EFFECT WILL BE MUCH MORE INTENSE.
RADAR DATA THROUGH THE DAY CONFIRMING THIS WITH UPWARDS OF 60 DBZ
TOTAL REFLECTIVITY BEING OBSERVED. 500MB DEFORMATION AND TEMPS
INDICATING AT LEAST ONE FRONTOGENETIC BAND IS MOVING NORTH ACROSS
THE PANHANDLE TODAY. ALL THIS ADDS UP TO A SIGNIFICANT INCREASE TO
THE SNOW TOTALS IN THE SHORT RANGE FORECAST ISSUED THIS AFTERNOON.

THINK THE RAIN-SNOW LINE WILL REMAIN SOMEWHERE BETWEEN ANGOON AND
ICY STRAIT FOR MOST OF THE NIGHT, SO HAVE RAIN FOR MOST OF THE
SOUTHERN PANHANDLE. RAIN HEAVY AT TIMES FOR THE FAR SOUTHERN
PORTION OF THE PANHANDLE. COORDINATED WITH ENVIRONMENT CANADA
REGARDING THE AREA AROUND HYDER AND STEWART WITH A RAIN-SNOW MIX
FOR BOTH TONIGHT AND TOMORROW MORNING. NOT ANTICIPATING MORE THAN
1 INCH THERE.

BLENDED NAM, GFS, AND GEM FOR UPDATES TO PRESSURE WITH THE GEM
BEING USED TO MORE CLEARLY CAPTURE A WAVE DEVELOPING INTO A SURFACE
LOW ALONG THE FRONTAL BOUNDARY. POP AND QPF PRIMARILY FROM NAM
WITH A LITTLE HELP FROM GFS. TEMPS PRIMARILY PER GFS MOS. OVERALL
FORECAST CONFIDENCE IS AVERAGE.

.LONG TERM...MODELS BEGINNING TO SHOW INCREASING THREAT FOR PRECIP
TO THE SRN AREA LATER THU NIGHT/FRI. GEM/EC/NAM ALL SHOW A LOW
MOVING NE TOWARD THE FAR SERN AREA...WITH SOME DIFFS IN EXACT
TRACK AND STRENGTH BETWEEN THE MODELS. USED BLEND OF THE 12Z GEM/EC/NAM
TO HANDLE THIS SYSTEM. POPS RAISED TO LIKELY BY EARLY FRI FOR THE
FAR SRN ZONES...WITH CHANCE POPS FOR THE S-CENTRAL AREA. ALSO
DRIED THINGS OUT SOME OVER THE NRN AREAS DUE TO THIS SYSTEM
TURNING FLOW OFFSHORE QUICKER. COLDER AIR SHOULD PUSH IN FROM THE
N ONCE SYSTEM MOVES OUT OF THE AREA FRI NIGHT AND SAT.

FOR THE WEEKEND AND BEYOND...ENDED UP MAINTAINING THE GEM/EC/NAM BLEND
THRU SAT...THEN WENT WITH LATEST WPC FROM SUN ONWARD. BLENDED WPC
WITH THE GEM/EC FOR SAT NIGHT. STRONG HIGH PRESSURE WILL BUILD
OVER INTERIOR AK AND NW CANADA. LOOKING LIKE A FRONT WILL TRY TO
MOVE NWD INTO THE AREA FOR THE SAT NIGHT-SUN PERIOD...BUT IT WILL
RUN INTO THE COLDER AND DRIER AIR MOVING SWD. THINK BEST THREAT
FOR PRECIP WILL BE OVER THE SRN HALF OF THE AREA WITH THIS SYSTEM.
LOOKS LIKE THE ARCTIC HIGH WILL FINALLY SLIDE OFF TO THE SE EARLY
NEXT WEEK WITH MORE SYSTEMS COMING TOWARD THE AREA FROM THE
SW...SO LOOKS LIKE INCREASING PRECIP THREAT AND MODERATION OF
TEMPS WILL OCCUR. SIGNIFICANT MODEL DIFFERENCES WHERE THE
SHORTWAVE ENERGY GOES HOWEVER...SO CONFIDENCE IN EXACT TIMING/TRACK
OF SYSTEMS NEXT WEEK IS BELOW AVERAGE.

&&

.AVIATION...MAIN IMPACTS TO AVIATION ACTIVITIES WILL BE REDUCED
VISIBILITIES IN SNOW. WIDESPREAD CEILINGS BELOW MOST PANHANDLE
MOUNTAINTOPS. AND ICING, MOSTLY RIME, HAS BEEN REPORTED BELOW FL100 IN
PIREPS TODAY. AM FULLY EXPECTING THOSE CONDITIONS TO CONTINUE
THROUGH TOMORROW AFTERNOON. SEE AAWU AIRMETS ZULU AND SIERRA AS
WELL AS THE APPLICABLE FA FOR ADDITIONAL INFORMATION.

&&

.AJK WATCHES/WARNINGS/ADVISORIES...
PUBLIC...WINTER WEATHER ADVISORY UNTIL 6 AM AKST THURSDAY FOR AKZ025.
         WINTER STORM WARNING UNTIL NOON AKST THURSDAY FOR AKZ019.
         WINTER WEATHER ADVISORY UNTIL NOON AKST THURSDAY FOR AKZ018-020.
         STRONG WIND UNTIL 4 PM AKST THIS AFTERNOON FOR AKZ018.
MARINE...GALE WARNING FOR PKZ022-036-041.
         SMALL CRAFT ADVISORY FOR PKZ011>013-021-031>035-042-043-051-052.

&&

$$

FRITSCH/RWT

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










000
FXAK67 PAJK 290032
AFDAJK

SOUTHEAST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE JUNEAU AK
332 PM AKST WED JAN 28 2015

.SHORT TERM...COLD AIR HAS REMAINED IN PLACE THROUGH THE DAY SUCH
THAT THOSE LOCATIONS WHICH WOKE UP TO SNOW THIS MORNING ARE STILL
SEEING SNOW. VERY LITTLE CHANGE TO TEMPERATURES EXPECTED
OVERNIGHT AND PLENTY OF MOISTURE STREAMING IN FROM THE SOUTH, SO
MORE SNOW IS FORECAST OVERNIGHT. HAVE ISSUED A WINTER STORM WARNING
FOR HAINES, AND HAVE WINTER WEATHER ADVISORIES FOR GUSTAVUS,
SKAGWAY, AND HAINES. A VERY MODEST INCREASE IN TEMPS OVERNIGHT IN
THE JUNEAU AREA IS POSSIBLE AND TEMPS ARE MOST LIKELY GOING TO
RISE ABOVE FREEZING TOMORROW, SO THAT ADVISORY WILL END FIRST AT
6AM.

SATELLITE IMAGERY IS SHOWING A FRONT ORIENTED NORTH-SOUTH AND
MOVING NNE OVER THE PANHANDLE. WATER VAPOR IMAGERY ALSO REVEALING
A BROAD AND SOLID CONNECTION TO LOW LATITUDE MOISTURE SOURCE. TPW
VALUES FAIRLY MODEST AT AROUND 1 INCH BUT WITH THE TRAINING MOTION
OVER SOUTHEAST ALASKA, THE NET EFFECT WILL BE MUCH MORE INTENSE.
RADAR DATA THROUGH THE DAY CONFIRMING THIS WITH UPWARDS OF 60 DBZ
TOTAL REFLECTIVITY BEING OBSERVED. 500MB DEFORMATION AND TEMPS
INDICATING AT LEAST ONE FRONTOGENETIC BAND IS MOVING NORTH ACROSS
THE PANHANDLE TODAY. ALL THIS ADDS UP TO A SIGNIFICANT INCREASE TO
THE SNOW TOTALS IN THE SHORT RANGE FORECAST ISSUED THIS AFTERNOON.

THINK THE RAIN-SNOW LINE WILL REMAIN SOMEWHERE BETWEEN ANGOON AND
ICY STRAIT FOR MOST OF THE NIGHT, SO HAVE RAIN FOR MOST OF THE
SOUTHERN PANHANDLE. RAIN HEAVY AT TIMES FOR THE FAR SOUTHERN
PORTION OF THE PANHANDLE. COORDINATED WITH ENVIRONMENT CANADA
REGARDING THE AREA AROUND HYDER AND STEWART WITH A RAIN-SNOW MIX
FOR BOTH TONIGHT AND TOMORROW MORNING. NOT ANTICIPATING MORE THAN
1 INCH THERE.

BLENDED NAM, GFS, AND GEM FOR UPDATES TO PRESSURE WITH THE GEM
BEING USED TO MORE CLEARLY CAPTURE A WAVE DEVELOPING INTO A SURFACE
LOW ALONG THE FRONTAL BOUNDARY. POP AND QPF PRIMARILY FROM NAM
WITH A LITTLE HELP FROM GFS. TEMPS PRIMARILY PER GFS MOS. OVERALL
FORECAST CONFIDENCE IS AVERAGE.

.LONG TERM...MODELS BEGINNING TO SHOW INCREASING THREAT FOR PRECIP
TO THE SRN AREA LATER THU NIGHT/FRI. GEM/EC/NAM ALL SHOW A LOW
MOVING NE TOWARD THE FAR SERN AREA...WITH SOME DIFFS IN EXACT
TRACK AND STRENGTH BETWEEN THE MODELS. USED BLEND OF THE 12Z GEM/EC/NAM
TO HANDLE THIS SYSTEM. POPS RAISED TO LIKELY BY EARLY FRI FOR THE
FAR SRN ZONES...WITH CHANCE POPS FOR THE S-CENTRAL AREA. ALSO
DRIED THINGS OUT SOME OVER THE NRN AREAS DUE TO THIS SYSTEM
TURNING FLOW OFFSHORE QUICKER. COLDER AIR SHOULD PUSH IN FROM THE
N ONCE SYSTEM MOVES OUT OF THE AREA FRI NIGHT AND SAT.

FOR THE WEEKEND AND BEYOND...ENDED UP MAINTAINING THE GEM/EC/NAM BLEND
THRU SAT...THEN WENT WITH LATEST WPC FROM SUN ONWARD. BLENDED WPC
WITH THE GEM/EC FOR SAT NIGHT. STRONG HIGH PRESSURE WILL BUILD
OVER INTERIOR AK AND NW CANADA. LOOKING LIKE A FRONT WILL TRY TO
MOVE NWD INTO THE AREA FOR THE SAT NIGHT-SUN PERIOD...BUT IT WILL
RUN INTO THE COLDER AND DRIER AIR MOVING SWD. THINK BEST THREAT
FOR PRECIP WILL BE OVER THE SRN HALF OF THE AREA WITH THIS SYSTEM.
LOOKS LIKE THE ARCTIC HIGH WILL FINALLY SLIDE OFF TO THE SE EARLY
NEXT WEEK WITH MORE SYSTEMS COMING TOWARD THE AREA FROM THE
SW...SO LOOKS LIKE INCREASING PRECIP THREAT AND MODERATION OF
TEMPS WILL OCCUR. SIGNIFICANT MODEL DIFFERENCES WHERE THE
SHORTWAVE ENERGY GOES HOWEVER...SO CONFIDENCE IN EXACT TIMING/TRACK
OF SYSTEMS NEXT WEEK IS BELOW AVERAGE.

&&

.AVIATION...MAIN IMPACTS TO AVIATION ACTIVITIES WILL BE REDUCED
VISIBILITIES IN SNOW. WIDESPREAD CEILINGS BELOW MOST PANHANDLE
MOUNTAINTOPS. AND ICING, MOSTLY RIME, HAS BEEN REPORTED BELOW FL100 IN
PIREPS TODAY. AM FULLY EXPECTING THOSE CONDITIONS TO CONTINUE
THROUGH TOMORROW AFTERNOON. SEE AAWU AIRMETS ZULU AND SIERRA AS
WELL AS THE APPLICABLE FA FOR ADDITIONAL INFORMATION.

&&

.AJK WATCHES/WARNINGS/ADVISORIES...
PUBLIC...WINTER WEATHER ADVISORY UNTIL 6 AM AKST THURSDAY FOR AKZ025.
         WINTER STORM WARNING UNTIL NOON AKST THURSDAY FOR AKZ019.
         WINTER WEATHER ADVISORY UNTIL NOON AKST THURSDAY FOR AKZ018-020.
         STRONG WIND UNTIL 4 PM AKST THIS AFTERNOON FOR AKZ018.
MARINE...GALE WARNING FOR PKZ022-036-041.
         SMALL CRAFT ADVISORY FOR PKZ011>013-021-031>035-042-043-051-052.

&&

$$

FRITSCH/RWT

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











000
FXAK67 PAJK 281430
AFDAJK

SOUTHEAST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE JUNEAU AK
530 AM AKST WED JAN 28 2015

.SHORT TERM...A BROAD LOW PRESSURE AREA OVER THE NORTH PACIFIC AND
GULF OF ALASKA. THE MAIN LOW CENTER IS SOUTH OF THE EASTERN
ALEUTIANS AND WILL CONTINUE TO ROTATE SOUTHWARD INTO THE NORTH
PACIFIC. AN EXTENDED TROUGH IS INTO THE GULF OF ALASKA ASSOCIATED
WITH THE FRONT LIFTING THROUGH THE PANHANDLE. RAIN IS OVER THE
SOUTHERN PANHANDLE WITH THE RAIN SNOW LINE MOVING NORTHWARD TO
NEAR ICY STRAIT TO NEAR JUNEAU BY LATE AFTERNOON AND EVENING.
NORTHERLY WINDS THROUGH LYNN CANAL WILL CONTINUE TO REINFORCE COLD
AIR IN THE NORTHERN LYNN CANAL AND THUS WILL KEEP THE
PRECIPITATION AS SNOW OVER THAT REGION.

SNOW STARTING IN THE JUNEAU AREA, STARTING EARLY WEDNESDAY MORNING
AND THINK THE SNOW WILL LIKELY CHANGE OVER TO RAIN AT THE LOWER
LEVELS THROUGH THE AFTERNOON...ALTHOUGH SNOW LEVEL ONLY RISING TO
ROUGHLY A 1000 FEET. THROUGH MORNING TO MID DAY TEMPERATURES AHEAD
OF THE FRONT WARMING TO AND SLIGHTLY ABOVE FREEZING WITH THE DEW
POINT KEEPING PRECIPITATION AS A WET SNOW.

STILL A BAND OF GALE FORCE WINDS ALONG THE OUTER COAST THROUGH EARLY
WEDNESDAY AHEAD OF THE FRONT. GALES INTO CLARENCE STRAIT TODAY AS
WELL WHILE THE FRONT WILL GO. NORTH WINDS IN THE LYNN CANAL ARE TO
SMALL CRAFT LEVELS WILL LOWER TO JUST UNDER SMALL CRAFT LEVELS.

MISTY FJORDS HANG ON TO SOME COOLER TEMPERATURES AND AN OFFSHORE FLOW
SO EXPECTING SOME COOLER TEMPERATURES SO AM EXPECTING SOME SNOW
WITH ACCUMULATIONS UP TO 2 TO 5 INCHES PERHAPS OVERNIGHT.

.LONG TERM...LARGE UPPER-LEVEL VORTEX OBSERVED S OF THE ALEUTIANS
THIS MORNING IS FORECAST TO REMAIN QUASI-STATIONARY THROUGH MOST
OF THE LONG TERM PERIOD AS A RIDGE BUILDS FROM W TO E ACROSS
INTERIOR AK AND NWRN CANADA. THIS WILL LIKELY LOCK SERN AK INTO A
COLDER/DRIER PATTERN /RELATIVE TO THE PAST MONTH/ WITH PERIODS OF
OCCASIONALLY STRONG OUTFLOW WINDS.

THU INTO FRI...A DEEP LAYER OF DRY AIR IS FORECAST TO SPREAD FROM
S TO N OVER THE PANHANDLE AS MIDLEVEL HEIGHTS RISE OVER THE ERN
GULF. AS A RESULT...PRECIPITATION CHANCES WILL DIMINISH TO ZERO
OVER SRN AREAS BY THU NIGHT...WITH LINGERING LIGHT SNOW/RAIN
OCCURRING OVER NRN AREAS ENDING BY FRI NIGHT. THE WEEKEND WILL
THEN BE DOMINATED BY STRONG OUTFLOW WINDS AS HIGH PRESSURE BUILDS
OVER NWRN CANADA AND A SERIES OF FRONTAL BOUNDARIES
STALL/DISSIPATE OVER THE SRN GULF. GALES ARE PROBABLE FOR MANY OF
THE INNER CHANNELS SAT INTO SUN...WITH THE EXCEPTION OF CLARENCE
STRAIT...AND STRONG TO POTENTIALLY HIGH WINDS WILL DEVELOP OVER
SKAGWAY. ELSEWHERE...CROSS BARRIER FLOW IS FORECAST TO INTENSIFY
INVOF DOWNTOWN JUNEAU...AND A PRONOUNCED BOUNDARY LAYER INVERSION
WILL BE IN PLACE. IN ADDITION...MODEL GUIDANCE SHOWS A MIDLEVEL
VORT LOBE STALLING OVER THE AREA...WHICH WILL POTENTIALLY AID IN
MINIMIZING WIND SPEEDS ABOVE THE CROSS BARRIER WIND
MAXIMA...FAVORING THE DEVELOPMENT OF A CRITICAL LEVEL. THUS...A
TAKU WIND EVENT IS LOOKING MORE LIKELY.

A VERY DRY AIRMASS USHERED IN BY OFFSHORE WINDS WILL GREATLY
INHIBIT PRECIPITATION CHANCES DURING THE WEEKEND INTO EARLY NEXT
WEEK OVER THE NRN HALF OF THE CWA. UNCERTAINTY EXISTS OVER THE SRN
HALF...WHERE AN UPPER DISTURBANCE WILL APPROACH SUN AND MON.
THE GFS...AND THE GEM TO A LESSER EXTENT...ARE MOST AGGRESSIVE IN
SPREADING MOISTURE NWD...WHILE THE ECMWF MAINTAINS DEEP-LAYER
DRYNESS OVER THE ENTIRE REGION.

BLENDED IN THE ECMWF WITH INHERITED PRESSURE GRIDS THROUGH 15Z
SAT...THEN MAINTAINED PREVIOUS FORECAST THEREAFTER. USED A
COMBINATION OF THE ECMWF AND NAM FOR UPDATES TO POP GRIDS THROUGH
12Z SUN. POP FIELD WAS DECREASED SLIGHTLY GOING INTO EARLY NEXT
WEEK DUE TO THE DRY SIGNAL IN THE ECMWF...BUT WASN/T ENTIRELY
DIMINISHED TO ZERO DUE TO WETTER GFS SOLUTION.

&&

.AJK WATCHES/WARNINGS/ADVISORIES...
PUBLIC...NONE.
MARINE...GALE WARNING FOR PKZ022-036-041>043-051-052.
         SMALL CRAFT ADVISORY FOR PKZ011>013-021-031>035-053.

&&

$$

BEZENEK/GARNER

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







000
FXAK67 PAJK 281430
AFDAJK

SOUTHEAST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE JUNEAU AK
530 AM AKST WED JAN 28 2015

.SHORT TERM...A BROAD LOW PRESSURE AREA OVER THE NORTH PACIFIC AND
GULF OF ALASKA. THE MAIN LOW CENTER IS SOUTH OF THE EASTERN
ALEUTIANS AND WILL CONTINUE TO ROTATE SOUTHWARD INTO THE NORTH
PACIFIC. AN EXTENDED TROUGH IS INTO THE GULF OF ALASKA ASSOCIATED
WITH THE FRONT LIFTING THROUGH THE PANHANDLE. RAIN IS OVER THE
SOUTHERN PANHANDLE WITH THE RAIN SNOW LINE MOVING NORTHWARD TO
NEAR ICY STRAIT TO NEAR JUNEAU BY LATE AFTERNOON AND EVENING.
NORTHERLY WINDS THROUGH LYNN CANAL WILL CONTINUE TO REINFORCE COLD
AIR IN THE NORTHERN LYNN CANAL AND THUS WILL KEEP THE
PRECIPITATION AS SNOW OVER THAT REGION.

SNOW STARTING IN THE JUNEAU AREA, STARTING EARLY WEDNESDAY MORNING
AND THINK THE SNOW WILL LIKELY CHANGE OVER TO RAIN AT THE LOWER
LEVELS THROUGH THE AFTERNOON...ALTHOUGH SNOW LEVEL ONLY RISING TO
ROUGHLY A 1000 FEET. THROUGH MORNING TO MID DAY TEMPERATURES AHEAD
OF THE FRONT WARMING TO AND SLIGHTLY ABOVE FREEZING WITH THE DEW
POINT KEEPING PRECIPITATION AS A WET SNOW.

STILL A BAND OF GALE FORCE WINDS ALONG THE OUTER COAST THROUGH EARLY
WEDNESDAY AHEAD OF THE FRONT. GALES INTO CLARENCE STRAIT TODAY AS
WELL WHILE THE FRONT WILL GO. NORTH WINDS IN THE LYNN CANAL ARE TO
SMALL CRAFT LEVELS WILL LOWER TO JUST UNDER SMALL CRAFT LEVELS.

MISTY FJORDS HANG ON TO SOME COOLER TEMPERATURES AND AN OFFSHORE FLOW
SO EXPECTING SOME COOLER TEMPERATURES SO AM EXPECTING SOME SNOW
WITH ACCUMULATIONS UP TO 2 TO 5 INCHES PERHAPS OVERNIGHT.

.LONG TERM...LARGE UPPER-LEVEL VORTEX OBSERVED S OF THE ALEUTIANS
THIS MORNING IS FORECAST TO REMAIN QUASI-STATIONARY THROUGH MOST
OF THE LONG TERM PERIOD AS A RIDGE BUILDS FROM W TO E ACROSS
INTERIOR AK AND NWRN CANADA. THIS WILL LIKELY LOCK SERN AK INTO A
COLDER/DRIER PATTERN /RELATIVE TO THE PAST MONTH/ WITH PERIODS OF
OCCASIONALLY STRONG OUTFLOW WINDS.

THU INTO FRI...A DEEP LAYER OF DRY AIR IS FORECAST TO SPREAD FROM
S TO N OVER THE PANHANDLE AS MIDLEVEL HEIGHTS RISE OVER THE ERN
GULF. AS A RESULT...PRECIPITATION CHANCES WILL DIMINISH TO ZERO
OVER SRN AREAS BY THU NIGHT...WITH LINGERING LIGHT SNOW/RAIN
OCCURRING OVER NRN AREAS ENDING BY FRI NIGHT. THE WEEKEND WILL
THEN BE DOMINATED BY STRONG OUTFLOW WINDS AS HIGH PRESSURE BUILDS
OVER NWRN CANADA AND A SERIES OF FRONTAL BOUNDARIES
STALL/DISSIPATE OVER THE SRN GULF. GALES ARE PROBABLE FOR MANY OF
THE INNER CHANNELS SAT INTO SUN...WITH THE EXCEPTION OF CLARENCE
STRAIT...AND STRONG TO POTENTIALLY HIGH WINDS WILL DEVELOP OVER
SKAGWAY. ELSEWHERE...CROSS BARRIER FLOW IS FORECAST TO INTENSIFY
INVOF DOWNTOWN JUNEAU...AND A PRONOUNCED BOUNDARY LAYER INVERSION
WILL BE IN PLACE. IN ADDITION...MODEL GUIDANCE SHOWS A MIDLEVEL
VORT LOBE STALLING OVER THE AREA...WHICH WILL POTENTIALLY AID IN
MINIMIZING WIND SPEEDS ABOVE THE CROSS BARRIER WIND
MAXIMA...FAVORING THE DEVELOPMENT OF A CRITICAL LEVEL. THUS...A
TAKU WIND EVENT IS LOOKING MORE LIKELY.

A VERY DRY AIRMASS USHERED IN BY OFFSHORE WINDS WILL GREATLY
INHIBIT PRECIPITATION CHANCES DURING THE WEEKEND INTO EARLY NEXT
WEEK OVER THE NRN HALF OF THE CWA. UNCERTAINTY EXISTS OVER THE SRN
HALF...WHERE AN UPPER DISTURBANCE WILL APPROACH SUN AND MON.
THE GFS...AND THE GEM TO A LESSER EXTENT...ARE MOST AGGRESSIVE IN
SPREADING MOISTURE NWD...WHILE THE ECMWF MAINTAINS DEEP-LAYER
DRYNESS OVER THE ENTIRE REGION.

BLENDED IN THE ECMWF WITH INHERITED PRESSURE GRIDS THROUGH 15Z
SAT...THEN MAINTAINED PREVIOUS FORECAST THEREAFTER. USED A
COMBINATION OF THE ECMWF AND NAM FOR UPDATES TO POP GRIDS THROUGH
12Z SUN. POP FIELD WAS DECREASED SLIGHTLY GOING INTO EARLY NEXT
WEEK DUE TO THE DRY SIGNAL IN THE ECMWF...BUT WASN/T ENTIRELY
DIMINISHED TO ZERO DUE TO WETTER GFS SOLUTION.

&&

.AJK WATCHES/WARNINGS/ADVISORIES...
PUBLIC...NONE.
MARINE...GALE WARNING FOR PKZ022-036-041>043-051-052.
         SMALL CRAFT ADVISORY FOR PKZ011>013-021-031>035-053.

&&

$$

BEZENEK/GARNER

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








000
FXAK67 PAJK 280125
AFDAJK

SOUTHEAST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE JUNEAU AK
425 PM AKST TUE JAN 27 2015

.SHORT TERM...A 982 MB LOW IN THE WESTERN GULF IS NEAR MAXIMUM
INTENSITY. AN OCCLUDED FRONT EXTENDS EAST FROM THE LOW TO A TRIPLE
POINT THE EAST-CENTRAL GULF, THEN SOUTH-SOUTHWEST AS A COLD FRONT INTO
THE NORTH PACIFIC. THE ENTIRE FRONTAL BOUNDARY IS GENERALLY
EXPANDING TO THE NORTH AND EAST, WITH THE OCCLUDED PORTION OVER
THE GULF BEGINNING TO SHEAR APART. THE FRONT SHOULD MAKE LANDFALL
OVER THE CENTRAL OUTER COAST LATE TONIGHT OR EARLY TOMORROW
MORNING WITH PRECIP BEGINNING AS RAIN FOR LOCATIONS SOUTH OF
ANGOON. EXCEPTION IS PETERSBURG WHERE UP TO AROUND 2 INCHES OF
SNOW IS FORECAST FROM LATE TONIGHT THROUGH NOON TOMORROW. FARTHER
NORTH, SNOW IS FORECAST TO START EARLY IN THE MORNING AND IS
EXPECTED TO PRODUCE 2 TO 3 INCHES THROUGH THE DAY FROM TENAKEE
SPRINGS NORTH, AND FROM THE OUTER COAST EAST TO THE COAST
MOUNTAINS. HEAVIEST SNOWFALL LOOKS LIKE IT WILL BE IN THE AREA
AROUND GUSTAVUS AND JUNEAU. FARTHER NORTH, THE OCCLUDED FRONT WILL
BE WEAKENING AS IT SHEARS APART. FARTHER SOUTH, RAIN WILL BE
MIXING IN WITH THE SNOW, LOWERING THE SNOW TO LIQUID RATIO. ITS
NOT A LOT, BUT BETTER THAN NOTHING.

AS THE FRONT SWEEPS NORTHWARD, THE NORTHEASTERLY PRESSURE GRADIENT
WILL INCREASE SHARPLY. HAVE A GALE WARNING OUT FOR NORTHERN LYNN
AS A RESULT AND WINDY CONDITIONS IN SKAGWAY. CONSIDERED PUTTING IN
A STRONG WIND HEADLINE AND I THINK AN OCCASIONAL 40 MPH GUST IS
PROBABLE, BUT THE MAJORITY OF THE WIND GUSTS SHOULD BE 35 MPH OR
SO. ELSEWHERE, ALSO HAVE A GALE WARNING OUT FOR EASTERLIES OUT OF CROSS
SOUND, MOST OF THE COASTAL MARINE ZONES, AND CLARENCE STRAIT.

USED A BLEND OF NAM AND GFS FOR UPDATES TO PRESSURE AND WIND
TODAY. POP AND QPF FROM AN EVEN BLEND OF GFS, GEM, AND ECMWF.
ADJUSTMENTS TO TEMPS PER GFS40. OVERALL FORECAST CONFIDENCE IS
AVERAGE TO SLIGHTLY ABOVE AVERAGE.

.LONG TERM...LOW PRESSURE WAVE WILL MOVE N INTO THE ERN GULF WED
NIGHT. LOOKS LIKE IT WILL DISSIPATE AS IT COMES ONSHORE OVER THE
NRN AREA THU MORNING. MODELS DIFFER ON TRACK SOMEWHAT FOR THU
THOUGH...SO CONFIDENCE IS FAIRLY LOW ON ITS TRACK. HIGH PRESSURE
WILL BUILD OVER MUCH OF INTERIOR AK AND NW CANADA FOR FRI INTO THE
WEEKEND. THIS WILL INCREASE NLY FLOW...AND GENERALLY DRY THINGS
OUT. USED BLEND OF THE 12Z GFS/18Z NAM FOR WED NIGHT/THU...THEN
TRANSITIONED TO A 12Z ECMWF/GEM BLEND BY LATE THU NIGHT AND FRI.
DID USE MORE WEIGHT TO THE ECMWF THOUGH DUE TO THE GEM OVERDOING
THE SFC HIGH. FOR FRI NIGHT ONWARD...BASICALLY USED WPC.

FOR WED NIGHT AND THU...PRECIP WILL INCREASE OVER THE MAIN PART OF
THE PANHANDLE AS LOW PRESSURE WAVE RIDES NWD. THE BIGGEST CONCERN
IS PTYPE FROM PAJN NWD. THE FURTHER W THE LOW MOVES...THE MORE
LIKELY LOW LEVEL FLOW WILL TURN SELY AND WARM LOW LEVEL TEMPS. IF
THE 12Z GFS/18Z NAM WORK OUT...MAY END UP WITH MORE SNOW FROM PAJN
NWD THAN CURRENTLY FORECAST. AT THIS POINT...UNTIL LOW TRACK IS
MORE CERTAIN...DECIDED TO USE RAIN AND SNOW FOR THE PAJN AREA.
AREAS TO THE N SHOULD BE MOSTLY SNOW. COULD SEE SEVERAL INCHES OF
SNOW FROM THIS ESPECIALLY OVER THE FAR N...AND LATER SHIFTS MAY
NEED TO ISSUE AT LEAST A WINTER WX ADVY. EVENTUALLY...SHOULD SEE
WARMER AIR MOVE IN THU...SO EVEN THE FAR NRN AREAS MAY GET SOME
RAIN TO MIX IN.

FOR THU NIGHT AND FRI...PRECIP OVER THE AREA WILL DIMINISH AS
OFFSHORE FLOW DEVELOPS. THIS MAY TAKE THE LONGEST OVER THE NRN
AREA THOUGH AS REMNANT OF FRONT SLOWLY DISSIPATES THERE. THINK IT
WILL BE MOSTLY DRY BY LATE IN THE DAY FRI OVER THE N. THE S SHOULD
DRY OUT SOONER...PROBABLY BY EARLY FRI MORNING.

FOR THE WEEKEND...DID LOWER POPS AND TEMPS. COLDER AIR SHOULD
FILTER INTO THE AREA ESPECIALLY OVER THE NRN HALF AS HIGH PRESSURE
BUILDS TO THE N. THINK MOST OTHER SYSTEMS WILL BE FORCED TO STAY
SW OF THE AREA DURING THE WEEKEND DUE TO THIS HIGH...ALTHOUGH A
FRONT MAY THREATEN THE FAR SRN AREAS SUN. MODEL DIFFERENCES GET
RATHER LARGE THOUGH HANDLING INDIVIDUAL SYSTEMS EMBEDDED IN THE
LARGER SCALE LOW TO THE S OF THE GULF...SO NOT OVERLY CONFIDENT ON
THIS ASPECT OF THE FORECAST. MAY SEE INCREASING THREAT FOR PRECIP
EARLY NEXT WEEK AS SOME SRN STREAM ENERGY TRIES TO MOVE IN. ALL IN
ALL...FORECAST CONFIDENCE IS BELOW AVERAGE.

&&

.AVIATION...FORECAST 850MB WINDS SUGGESTING THAT THERE WILL BE
WIDESPREAD LIGHT TO MODERATE TURBULENCE SOUTH OF THE ICY STRAIT
CORRIDOR THROUGH THE SHORT TERM PERIOD. LOCALIZED REDUCTIONS IN
VISIBILITIES IN HEAVIER SNOW WILL PRODUCE IMC CONDITIONS BELOW
CLOUD BASES, WHICH ARE EXPECTED TO BE IN THE 1500 FOOT RANGE OR
HIGHER. SEE THE AAWU AIRMETS SIERRA, AND TANGO FOR ADDITIONAL
DETAILS.

&&

.AJK WATCHES/WARNINGS/ADVISORIES...
PUBLIC...NONE.
MARINE...GALE WARNING FOR PKZ022-036-041>043-051.
         SMALL CRAFT ADVISORY FOR PKZ011>013-021-031>035-052-053.

&&

$$

FRITSCH/RWT

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








000
FXAK67 PAJK 280125
AFDAJK

SOUTHEAST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE JUNEAU AK
425 PM AKST TUE JAN 27 2015

.SHORT TERM...A 982 MB LOW IN THE WESTERN GULF IS NEAR MAXIMUM
INTENSITY. AN OCCLUDED FRONT EXTENDS EAST FROM THE LOW TO A TRIPLE
POINT THE EAST-CENTRAL GULF, THEN SOUTH-SOUTHWEST AS A COLD FRONT INTO
THE NORTH PACIFIC. THE ENTIRE FRONTAL BOUNDARY IS GENERALLY
EXPANDING TO THE NORTH AND EAST, WITH THE OCCLUDED PORTION OVER
THE GULF BEGINNING TO SHEAR APART. THE FRONT SHOULD MAKE LANDFALL
OVER THE CENTRAL OUTER COAST LATE TONIGHT OR EARLY TOMORROW
MORNING WITH PRECIP BEGINNING AS RAIN FOR LOCATIONS SOUTH OF
ANGOON. EXCEPTION IS PETERSBURG WHERE UP TO AROUND 2 INCHES OF
SNOW IS FORECAST FROM LATE TONIGHT THROUGH NOON TOMORROW. FARTHER
NORTH, SNOW IS FORECAST TO START EARLY IN THE MORNING AND IS
EXPECTED TO PRODUCE 2 TO 3 INCHES THROUGH THE DAY FROM TENAKEE
SPRINGS NORTH, AND FROM THE OUTER COAST EAST TO THE COAST
MOUNTAINS. HEAVIEST SNOWFALL LOOKS LIKE IT WILL BE IN THE AREA
AROUND GUSTAVUS AND JUNEAU. FARTHER NORTH, THE OCCLUDED FRONT WILL
BE WEAKENING AS IT SHEARS APART. FARTHER SOUTH, RAIN WILL BE
MIXING IN WITH THE SNOW, LOWERING THE SNOW TO LIQUID RATIO. ITS
NOT A LOT, BUT BETTER THAN NOTHING.

AS THE FRONT SWEEPS NORTHWARD, THE NORTHEASTERLY PRESSURE GRADIENT
WILL INCREASE SHARPLY. HAVE A GALE WARNING OUT FOR NORTHERN LYNN
AS A RESULT AND WINDY CONDITIONS IN SKAGWAY. CONSIDERED PUTTING IN
A STRONG WIND HEADLINE AND I THINK AN OCCASIONAL 40 MPH GUST IS
PROBABLE, BUT THE MAJORITY OF THE WIND GUSTS SHOULD BE 35 MPH OR
SO. ELSEWHERE, ALSO HAVE A GALE WARNING OUT FOR EASTERLIES OUT OF CROSS
SOUND, MOST OF THE COASTAL MARINE ZONES, AND CLARENCE STRAIT.

USED A BLEND OF NAM AND GFS FOR UPDATES TO PRESSURE AND WIND
TODAY. POP AND QPF FROM AN EVEN BLEND OF GFS, GEM, AND ECMWF.
ADJUSTMENTS TO TEMPS PER GFS40. OVERALL FORECAST CONFIDENCE IS
AVERAGE TO SLIGHTLY ABOVE AVERAGE.

.LONG TERM...LOW PRESSURE WAVE WILL MOVE N INTO THE ERN GULF WED
NIGHT. LOOKS LIKE IT WILL DISSIPATE AS IT COMES ONSHORE OVER THE
NRN AREA THU MORNING. MODELS DIFFER ON TRACK SOMEWHAT FOR THU
THOUGH...SO CONFIDENCE IS FAIRLY LOW ON ITS TRACK. HIGH PRESSURE
WILL BUILD OVER MUCH OF INTERIOR AK AND NW CANADA FOR FRI INTO THE
WEEKEND. THIS WILL INCREASE NLY FLOW...AND GENERALLY DRY THINGS
OUT. USED BLEND OF THE 12Z GFS/18Z NAM FOR WED NIGHT/THU...THEN
TRANSITIONED TO A 12Z ECMWF/GEM BLEND BY LATE THU NIGHT AND FRI.
DID USE MORE WEIGHT TO THE ECMWF THOUGH DUE TO THE GEM OVERDOING
THE SFC HIGH. FOR FRI NIGHT ONWARD...BASICALLY USED WPC.

FOR WED NIGHT AND THU...PRECIP WILL INCREASE OVER THE MAIN PART OF
THE PANHANDLE AS LOW PRESSURE WAVE RIDES NWD. THE BIGGEST CONCERN
IS PTYPE FROM PAJN NWD. THE FURTHER W THE LOW MOVES...THE MORE
LIKELY LOW LEVEL FLOW WILL TURN SELY AND WARM LOW LEVEL TEMPS. IF
THE 12Z GFS/18Z NAM WORK OUT...MAY END UP WITH MORE SNOW FROM PAJN
NWD THAN CURRENTLY FORECAST. AT THIS POINT...UNTIL LOW TRACK IS
MORE CERTAIN...DECIDED TO USE RAIN AND SNOW FOR THE PAJN AREA.
AREAS TO THE N SHOULD BE MOSTLY SNOW. COULD SEE SEVERAL INCHES OF
SNOW FROM THIS ESPECIALLY OVER THE FAR N...AND LATER SHIFTS MAY
NEED TO ISSUE AT LEAST A WINTER WX ADVY. EVENTUALLY...SHOULD SEE
WARMER AIR MOVE IN THU...SO EVEN THE FAR NRN AREAS MAY GET SOME
RAIN TO MIX IN.

FOR THU NIGHT AND FRI...PRECIP OVER THE AREA WILL DIMINISH AS
OFFSHORE FLOW DEVELOPS. THIS MAY TAKE THE LONGEST OVER THE NRN
AREA THOUGH AS REMNANT OF FRONT SLOWLY DISSIPATES THERE. THINK IT
WILL BE MOSTLY DRY BY LATE IN THE DAY FRI OVER THE N. THE S SHOULD
DRY OUT SOONER...PROBABLY BY EARLY FRI MORNING.

FOR THE WEEKEND...DID LOWER POPS AND TEMPS. COLDER AIR SHOULD
FILTER INTO THE AREA ESPECIALLY OVER THE NRN HALF AS HIGH PRESSURE
BUILDS TO THE N. THINK MOST OTHER SYSTEMS WILL BE FORCED TO STAY
SW OF THE AREA DURING THE WEEKEND DUE TO THIS HIGH...ALTHOUGH A
FRONT MAY THREATEN THE FAR SRN AREAS SUN. MODEL DIFFERENCES GET
RATHER LARGE THOUGH HANDLING INDIVIDUAL SYSTEMS EMBEDDED IN THE
LARGER SCALE LOW TO THE S OF THE GULF...SO NOT OVERLY CONFIDENT ON
THIS ASPECT OF THE FORECAST. MAY SEE INCREASING THREAT FOR PRECIP
EARLY NEXT WEEK AS SOME SRN STREAM ENERGY TRIES TO MOVE IN. ALL IN
ALL...FORECAST CONFIDENCE IS BELOW AVERAGE.

&&

.AVIATION...FORECAST 850MB WINDS SUGGESTING THAT THERE WILL BE
WIDESPREAD LIGHT TO MODERATE TURBULENCE SOUTH OF THE ICY STRAIT
CORRIDOR THROUGH THE SHORT TERM PERIOD. LOCALIZED REDUCTIONS IN
VISIBILITIES IN HEAVIER SNOW WILL PRODUCE IMC CONDITIONS BELOW
CLOUD BASES, WHICH ARE EXPECTED TO BE IN THE 1500 FOOT RANGE OR
HIGHER. SEE THE AAWU AIRMETS SIERRA, AND TANGO FOR ADDITIONAL
DETAILS.

&&

.AJK WATCHES/WARNINGS/ADVISORIES...
PUBLIC...NONE.
MARINE...GALE WARNING FOR PKZ022-036-041>043-051.
         SMALL CRAFT ADVISORY FOR PKZ011>013-021-031>035-052-053.

&&

$$

FRITSCH/RWT

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