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000
FXAK69 PAFG 302342
AFDAFG

NORTHERN ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE FAIRBANKS AK
342 PM AKDT TUE SEP 30 2014

.DISCUSSION...
THE NORTHWEST (OR WEST) FLOW ALOFT THAT HAS DEVELOPED OVER
ALL BUT OUR EASTERNMOST ZONES WILL SPREAD OVER THEM AS WELL
BY WEDNESDAY MORNING. THE PATTERN WILL BRING IN A SERIES OF
DISTURBANCES ALOFT WHICH WILL PRODUCE MAINLY SHOWERY
PRECIPITATION. MOST OF THOSE DISTURBANCES WILL BE POORLY
REFLECTED AT THE SURFACE. HOWEVER...THE MODELS ARE IN
FAIR AGREEMENT IN DEALING WITH ONE OF THEM.

A 1008 MB LOW JUST WEST OF WRANGEL ISLAND IS EXPECTED TO MOVE
RAPIDLY EAST...PASSING NORTH OF CAPE LISBURNE TONIGHT... TO
CENTER BETWEEN BARROW AND PRUDHOE BAY AT 4 PM WEDNESDAY AT
AROUND 1012 MB. THE LOW WILL MOVE NORTHEAST OVER THE BEAUFORT SEA
TO BE ABOUT 150 NM NORTH OF DEMARCATION POINT AT 4AM THURSDAY.
THIS LITTLE LOW WILL BRING MOST OF OUR ARCTIC MARINE AREAS UP
TO 25 KT AT SOME POINT...THOUGH TYPICALLY JUST FOR 6 TO 12
HOURS.

THE RAIN-SNOW LINE WILL REMAIN OVER THE INTERIOR...AND THERE
WILL BE DIURNAL VARIATIONS IN PRECIPITATION TYPE AS WELL...BUT
PRECIPITATION AMOUNTS WILL BE LIGHT.

EXPECT SNOW ALONE OVER HIGHER TERRAIN IN ZONES 205 AND 206.
UP TO 2 INCHES AGAIN TONIGHT IN ZONE 206. SNOW SHOWERS MAY
GIVE ANOTHER INCH ON WEDNESDAY...THEN AROUND THAT MUCH LIKELY
AGAIN WEDNESDAY NIGHT.

COASTAL HAZARD POTENTIAL DAYS 3 AND 4...NONE

&&

.HYDROLOGY...NO ISSUES.

&&

.AFG WATCHES/WARNINGS/ADVISORIES...
SMALL CRAFT ADVISORY FOR PKZ225-PKZ230-PKZ235-PKZ240-PKZ245.
&&

$$

DJH SEP 14



000
FXAK69 PAFG 302342
AFDAFG

NORTHERN ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE FAIRBANKS AK
342 PM AKDT TUE SEP 30 2014

.DISCUSSION...
THE NORTHWEST (OR WEST) FLOW ALOFT THAT HAS DEVELOPED OVER
ALL BUT OUR EASTERNMOST ZONES WILL SPREAD OVER THEM AS WELL
BY WEDNESDAY MORNING. THE PATTERN WILL BRING IN A SERIES OF
DISTURBANCES ALOFT WHICH WILL PRODUCE MAINLY SHOWERY
PRECIPITATION. MOST OF THOSE DISTURBANCES WILL BE POORLY
REFLECTED AT THE SURFACE. HOWEVER...THE MODELS ARE IN
FAIR AGREEMENT IN DEALING WITH ONE OF THEM.

A 1008 MB LOW JUST WEST OF WRANGEL ISLAND IS EXPECTED TO MOVE
RAPIDLY EAST...PASSING NORTH OF CAPE LISBURNE TONIGHT... TO
CENTER BETWEEN BARROW AND PRUDHOE BAY AT 4 PM WEDNESDAY AT
AROUND 1012 MB. THE LOW WILL MOVE NORTHEAST OVER THE BEAUFORT SEA
TO BE ABOUT 150 NM NORTH OF DEMARCATION POINT AT 4AM THURSDAY.
THIS LITTLE LOW WILL BRING MOST OF OUR ARCTIC MARINE AREAS UP
TO 25 KT AT SOME POINT...THOUGH TYPICALLY JUST FOR 6 TO 12
HOURS.

THE RAIN-SNOW LINE WILL REMAIN OVER THE INTERIOR...AND THERE
WILL BE DIURNAL VARIATIONS IN PRECIPITATION TYPE AS WELL...BUT
PRECIPITATION AMOUNTS WILL BE LIGHT.

EXPECT SNOW ALONE OVER HIGHER TERRAIN IN ZONES 205 AND 206.
UP TO 2 INCHES AGAIN TONIGHT IN ZONE 206. SNOW SHOWERS MAY
GIVE ANOTHER INCH ON WEDNESDAY...THEN AROUND THAT MUCH LIKELY
AGAIN WEDNESDAY NIGHT.

COASTAL HAZARD POTENTIAL DAYS 3 AND 4...NONE

&&

.HYDROLOGY...NO ISSUES.

&&

.AFG WATCHES/WARNINGS/ADVISORIES...
SMALL CRAFT ADVISORY FOR PKZ225-PKZ230-PKZ235-PKZ240-PKZ245.
&&

$$

DJH SEP 14



000
FXAK69 PAFG 302342
AFDAFG

NORTHERN ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE FAIRBANKS AK
342 PM AKDT TUE SEP 30 2014

.DISCUSSION...
THE NORTHWEST (OR WEST) FLOW ALOFT THAT HAS DEVELOPED OVER
ALL BUT OUR EASTERNMOST ZONES WILL SPREAD OVER THEM AS WELL
BY WEDNESDAY MORNING. THE PATTERN WILL BRING IN A SERIES OF
DISTURBANCES ALOFT WHICH WILL PRODUCE MAINLY SHOWERY
PRECIPITATION. MOST OF THOSE DISTURBANCES WILL BE POORLY
REFLECTED AT THE SURFACE. HOWEVER...THE MODELS ARE IN
FAIR AGREEMENT IN DEALING WITH ONE OF THEM.

A 1008 MB LOW JUST WEST OF WRANGEL ISLAND IS EXPECTED TO MOVE
RAPIDLY EAST...PASSING NORTH OF CAPE LISBURNE TONIGHT... TO
CENTER BETWEEN BARROW AND PRUDHOE BAY AT 4 PM WEDNESDAY AT
AROUND 1012 MB. THE LOW WILL MOVE NORTHEAST OVER THE BEAUFORT SEA
TO BE ABOUT 150 NM NORTH OF DEMARCATION POINT AT 4AM THURSDAY.
THIS LITTLE LOW WILL BRING MOST OF OUR ARCTIC MARINE AREAS UP
TO 25 KT AT SOME POINT...THOUGH TYPICALLY JUST FOR 6 TO 12
HOURS.

THE RAIN-SNOW LINE WILL REMAIN OVER THE INTERIOR...AND THERE
WILL BE DIURNAL VARIATIONS IN PRECIPITATION TYPE AS WELL...BUT
PRECIPITATION AMOUNTS WILL BE LIGHT.

EXPECT SNOW ALONE OVER HIGHER TERRAIN IN ZONES 205 AND 206.
UP TO 2 INCHES AGAIN TONIGHT IN ZONE 206. SNOW SHOWERS MAY
GIVE ANOTHER INCH ON WEDNESDAY...THEN AROUND THAT MUCH LIKELY
AGAIN WEDNESDAY NIGHT.

COASTAL HAZARD POTENTIAL DAYS 3 AND 4...NONE

&&

.HYDROLOGY...NO ISSUES.

&&

.AFG WATCHES/WARNINGS/ADVISORIES...
SMALL CRAFT ADVISORY FOR PKZ225-PKZ230-PKZ235-PKZ240-PKZ245.
&&

$$

DJH SEP 14



000
FXAK69 PAFG 302342
AFDAFG

NORTHERN ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE FAIRBANKS AK
342 PM AKDT TUE SEP 30 2014

.DISCUSSION...
THE NORTHWEST (OR WEST) FLOW ALOFT THAT HAS DEVELOPED OVER
ALL BUT OUR EASTERNMOST ZONES WILL SPREAD OVER THEM AS WELL
BY WEDNESDAY MORNING. THE PATTERN WILL BRING IN A SERIES OF
DISTURBANCES ALOFT WHICH WILL PRODUCE MAINLY SHOWERY
PRECIPITATION. MOST OF THOSE DISTURBANCES WILL BE POORLY
REFLECTED AT THE SURFACE. HOWEVER...THE MODELS ARE IN
FAIR AGREEMENT IN DEALING WITH ONE OF THEM.

A 1008 MB LOW JUST WEST OF WRANGEL ISLAND IS EXPECTED TO MOVE
RAPIDLY EAST...PASSING NORTH OF CAPE LISBURNE TONIGHT... TO
CENTER BETWEEN BARROW AND PRUDHOE BAY AT 4 PM WEDNESDAY AT
AROUND 1012 MB. THE LOW WILL MOVE NORTHEAST OVER THE BEAUFORT SEA
TO BE ABOUT 150 NM NORTH OF DEMARCATION POINT AT 4AM THURSDAY.
THIS LITTLE LOW WILL BRING MOST OF OUR ARCTIC MARINE AREAS UP
TO 25 KT AT SOME POINT...THOUGH TYPICALLY JUST FOR 6 TO 12
HOURS.

THE RAIN-SNOW LINE WILL REMAIN OVER THE INTERIOR...AND THERE
WILL BE DIURNAL VARIATIONS IN PRECIPITATION TYPE AS WELL...BUT
PRECIPITATION AMOUNTS WILL BE LIGHT.

EXPECT SNOW ALONE OVER HIGHER TERRAIN IN ZONES 205 AND 206.
UP TO 2 INCHES AGAIN TONIGHT IN ZONE 206. SNOW SHOWERS MAY
GIVE ANOTHER INCH ON WEDNESDAY...THEN AROUND THAT MUCH LIKELY
AGAIN WEDNESDAY NIGHT.

COASTAL HAZARD POTENTIAL DAYS 3 AND 4...NONE

&&

.HYDROLOGY...NO ISSUES.

&&

.AFG WATCHES/WARNINGS/ADVISORIES...
SMALL CRAFT ADVISORY FOR PKZ225-PKZ230-PKZ235-PKZ240-PKZ245.
&&

$$

DJH SEP 14


  [top]

000
FXAK67 PAJK 302315
AFDAJK

SOUTHEAST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE JUNEAU AK
315 PM AKDT TUE SEP 30 2014

.SHORT TERM...THIS MORNINGS UPPER LEVEL LOW FROM THE NORTHEAST
GULF OF ALASKA CONTINUES TO JUMP MOST OF THE ENERGY IN TO
NORTHWEST BRITISH COLUMBIA. THERE REMAINS SOME ACTIVE HEAVIER
SHOWERS MOVING ACROSS THE NORTHERN PANHANDLE AND TOWARD BRITISH
COLUMBIA. SOME OF THESE HEAVIER SHOWERS THROUGH THE LATE AFTERNOON
HAVE BEEN SPARKING A FEW STRIKES OF LIGHTNING. DO NOT THINK THAT
THEY WILL CONTINUE MUCH MORE INTO THE EVENING.  SOUTHERN PANHANDLE
GETTING SOME ISOLATED SHOWERS THIS EVENING BUT MAJORITY AREA WAS
COVERED WITH LOWER CLOUD LEVELS.

THE REMAINS OF THE LOW WILL BE A TROUGH LYING ACROSS THE PANHANDLE
JUST SOUTH OF ICY STRAIT THIS EVENING THAT WILL BE MOVING SLOWLY
SOUTHWARD ACROSS THE PANHANDLE AND IS EXPECTED TO DISSIPATE NEAR
DIXON ENTRANCE WEDNESDAY. HIGH PRESSURE IS BUILDING OVER THE
ALASKAN INTERIOR AND YUKON TERRITORY. THIS IS EXPECTED TO INCREASE
THE NORTH GRADIENT AND OUTFLOW TONIGHT AND WEDNESDAY ACROSS THE
NORTH. THE COOLER AND DRIER HAS BEEN TRYING TO FILTER IN ALL DAY
ACROSS THE NORTH AND AS THE SHOWERS TAPER OFF AND END OVERNIGHT
LOOK FOR CLEARING TO START AND MOVE SOUTH AS WELL.

GALES FOR THE OFFSHORE WATERS AND TWO OF THE COASTAL ZONES TO
TAPER OFF TONIGHT WITH SMALL CRAFT WINDS AND SEAS FOR THE OUTER
WATER THROUGH MUCH OF WEDNESDAY. LYNN CANAL TO BE SMALL CRAFT FOR
WINDS TONIGHT AND WEDNESDAY FOR THE NORTH WINDS.

.LONG TERM...START OF THE LONG TERM WILL FEATURE A DRY CONTINENTAL
AIRMASS OVER SERN AK SUPPORTIVE OF A LARGE DIURNAL TEMPERATURE
SWING AS WED NIGHT TEMPERATURES IN THE 30S /POSSIBLY MID 20S INVOF
YAKUTAT/ WARM INTO THE UPPER 40S TO LOW 50S BY THU AFTERNOON.
ATTENTION QUICKLY TURNS TO AN UPPER TROUGH AND ASSOCIATED SURFACE
CYCLONE ENTERING THE GULF THU AFTERNOON AND NIGHT. A FRONTAL
BOUNDARY IS FORECAST TO ENTER THE SERN GULF AND FAR SRN PORTIONS
OF THE PANHANDLE THU NIGHT. STRONG WAA AND ISENTROPIC UPGLIDE WILL
DEVELOP ALONG AND N OF THE FRONT RESULTING IN THE DEVELOPMENT OF
RAIN QUICKLY SPREADING FROM SRN AREAS INTO CNTRL/NRN AREAS BY 12Z
FRI. BEST COMBINATION OF MOISTURE INFLUX AS WELL AS SYNOPTIC AND
OROGRAPHIC LIFT IS CURRENTLY FORECAST TO BE LOCATED OVER THE SRN
PANHANDLE...AND THUS WILL BE THE MOST PROBABLE LOCATION FOR HEAVY
RAINFALL.

DETERMINISTIC MODEL SOLUTIONS CONTINUE TO SHOW SUBSTANTIAL
VARIABILITY WITH THE EVOLUTION OF THE LOW OVER THE GULF. THE
ECMWF PRODUCES MULTIPLE LOW CENTERS...WHILE THE GFS AND GEM ARE
MORE CONSOLIDATED. THE GEM APPEARED TO BE A GOOD MIDDLE
GROUND...THUS USED THAT MODEL FOR A REFRESH OF PRESSURE FRI INTO
SAT MORNING BEFORE TRANSITIONING TO WPC GUIDANCE. DESPITE
DIFFERENCES IN SMALLER SCALE EVOLUTIONARY DETAILS...ALL GUIDANCE
IS IN AGREEMENT WITH THE DEVELOPMENT OF WIDESPREAD SMALL CRAFT AND
GALE FORCE WINDS FOR BOTH THE INNER CHANNELS AND OUTSIDE WATERS
THU THROUGH FRI. BORDERLINE STORM FORCE WINDS WILL BE POSSIBLE
OVER MARINE ZONES 41...42...43...AND 310 AS A 50-70 KT ELY LOW-
LEVEL JET LIFTS N THU AFTERNOON/NIGHT IMMEDIATELY AHEAD OF THE
FRONT. HIGH END GALE FORCE WINDS ALSO APPEAR PROBABLE OVER CROSS
SOUND.

ELSEWHERE...HIGHER RESOLUTION 12 KM NAM SHOWS 25-35 KT OF CROSS
BARRIER FLOW OVER SALISBURY RIDGE. THIS FLOW COMBINED WITH A LOW-
LEVEL INVERSION AND WIND REVERSAL ALOFT WILL FAVOR GUSTY NELY
WINDS IN DOWNTOWN JUNEAU AND S DOUGLAS THU AFTERNOON AND
NIGHT...WITH WINDS REMAINING ELEVATED AS SYNOPTIC SLYS SPREAD N
INTO THE AREA FRI MORNING. FARTHER S...PREVIOUSLY MENTIONED LLJ
TIED TO THE ADVANCING FRONTAL BOUNDARY WILL POSSIBLY YIELD GUSTS
UP TO 45 MPH OVER LAND ZONE 27 /CRAIG AND KLAWOCK AREA/.

UPPER TROUGH IS FORECAST TO PERSIST OVER THE GULF THROUGH THE
WEEKEND AND INTO EARLY/POSSIBLY MIDDLE OF NEXT WEEK. THIS WILL
LIKELY SUPPORT A PROLONGED PERIOD OF RAINY WEATHER. HOWEVER...DID
NOT ATTEMPT TO ADD A SUBSTANTIAL AMOUNT OF DETAIL TO THE FORECAST
DURING THESE LATER TIME PERIODS DUE TO INDIVIDUAL EPISODES OF RAIN
BEING TIED TO SMALL-SCALE/LOW PREDICTABILITY WAVES MOVING THROUGH
THE LARGE-SCALE TROUGH.

FORECAST CONFIDENCE IS ABOVE AVERAGE WITH REGARD TO WIDESPREAD
MARINE WIND HAZARDS THROUGH FRI. CONFIDENCE IN ONSET AND LOCATION
OF HEAVIEST PRECIPITATION IS AROUND AVERAGE. CONFIDENCE THEN FALLS
BELOW AVERAGE BY THE WEEKEND AND BEYOND.

&&

.AJK WATCHES/WARNINGS/ADVISORIES...
PUBLIC...NONE.
MARINE...GALE WARNING FOR PKZ042-043-052.
         SMALL CRAFT ADVISORY FOR PKZ012-013-031>033-041-051.

&&

$$

BEZENEK/GARNER

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







000
FXAK67 PAJK 302315
AFDAJK

SOUTHEAST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE JUNEAU AK
315 PM AKDT TUE SEP 30 2014

.SHORT TERM...THIS MORNINGS UPPER LEVEL LOW FROM THE NORTHEAST
GULF OF ALASKA CONTINUES TO JUMP MOST OF THE ENERGY IN TO
NORTHWEST BRITISH COLUMBIA. THERE REMAINS SOME ACTIVE HEAVIER
SHOWERS MOVING ACROSS THE NORTHERN PANHANDLE AND TOWARD BRITISH
COLUMBIA. SOME OF THESE HEAVIER SHOWERS THROUGH THE LATE AFTERNOON
HAVE BEEN SPARKING A FEW STRIKES OF LIGHTNING. DO NOT THINK THAT
THEY WILL CONTINUE MUCH MORE INTO THE EVENING.  SOUTHERN PANHANDLE
GETTING SOME ISOLATED SHOWERS THIS EVENING BUT MAJORITY AREA WAS
COVERED WITH LOWER CLOUD LEVELS.

THE REMAINS OF THE LOW WILL BE A TROUGH LYING ACROSS THE PANHANDLE
JUST SOUTH OF ICY STRAIT THIS EVENING THAT WILL BE MOVING SLOWLY
SOUTHWARD ACROSS THE PANHANDLE AND IS EXPECTED TO DISSIPATE NEAR
DIXON ENTRANCE WEDNESDAY. HIGH PRESSURE IS BUILDING OVER THE
ALASKAN INTERIOR AND YUKON TERRITORY. THIS IS EXPECTED TO INCREASE
THE NORTH GRADIENT AND OUTFLOW TONIGHT AND WEDNESDAY ACROSS THE
NORTH. THE COOLER AND DRIER HAS BEEN TRYING TO FILTER IN ALL DAY
ACROSS THE NORTH AND AS THE SHOWERS TAPER OFF AND END OVERNIGHT
LOOK FOR CLEARING TO START AND MOVE SOUTH AS WELL.

GALES FOR THE OFFSHORE WATERS AND TWO OF THE COASTAL ZONES TO
TAPER OFF TONIGHT WITH SMALL CRAFT WINDS AND SEAS FOR THE OUTER
WATER THROUGH MUCH OF WEDNESDAY. LYNN CANAL TO BE SMALL CRAFT FOR
WINDS TONIGHT AND WEDNESDAY FOR THE NORTH WINDS.

.LONG TERM...START OF THE LONG TERM WILL FEATURE A DRY CONTINENTAL
AIRMASS OVER SERN AK SUPPORTIVE OF A LARGE DIURNAL TEMPERATURE
SWING AS WED NIGHT TEMPERATURES IN THE 30S /POSSIBLY MID 20S INVOF
YAKUTAT/ WARM INTO THE UPPER 40S TO LOW 50S BY THU AFTERNOON.
ATTENTION QUICKLY TURNS TO AN UPPER TROUGH AND ASSOCIATED SURFACE
CYCLONE ENTERING THE GULF THU AFTERNOON AND NIGHT. A FRONTAL
BOUNDARY IS FORECAST TO ENTER THE SERN GULF AND FAR SRN PORTIONS
OF THE PANHANDLE THU NIGHT. STRONG WAA AND ISENTROPIC UPGLIDE WILL
DEVELOP ALONG AND N OF THE FRONT RESULTING IN THE DEVELOPMENT OF
RAIN QUICKLY SPREADING FROM SRN AREAS INTO CNTRL/NRN AREAS BY 12Z
FRI. BEST COMBINATION OF MOISTURE INFLUX AS WELL AS SYNOPTIC AND
OROGRAPHIC LIFT IS CURRENTLY FORECAST TO BE LOCATED OVER THE SRN
PANHANDLE...AND THUS WILL BE THE MOST PROBABLE LOCATION FOR HEAVY
RAINFALL.

DETERMINISTIC MODEL SOLUTIONS CONTINUE TO SHOW SUBSTANTIAL
VARIABILITY WITH THE EVOLUTION OF THE LOW OVER THE GULF. THE
ECMWF PRODUCES MULTIPLE LOW CENTERS...WHILE THE GFS AND GEM ARE
MORE CONSOLIDATED. THE GEM APPEARED TO BE A GOOD MIDDLE
GROUND...THUS USED THAT MODEL FOR A REFRESH OF PRESSURE FRI INTO
SAT MORNING BEFORE TRANSITIONING TO WPC GUIDANCE. DESPITE
DIFFERENCES IN SMALLER SCALE EVOLUTIONARY DETAILS...ALL GUIDANCE
IS IN AGREEMENT WITH THE DEVELOPMENT OF WIDESPREAD SMALL CRAFT AND
GALE FORCE WINDS FOR BOTH THE INNER CHANNELS AND OUTSIDE WATERS
THU THROUGH FRI. BORDERLINE STORM FORCE WINDS WILL BE POSSIBLE
OVER MARINE ZONES 41...42...43...AND 310 AS A 50-70 KT ELY LOW-
LEVEL JET LIFTS N THU AFTERNOON/NIGHT IMMEDIATELY AHEAD OF THE
FRONT. HIGH END GALE FORCE WINDS ALSO APPEAR PROBABLE OVER CROSS
SOUND.

ELSEWHERE...HIGHER RESOLUTION 12 KM NAM SHOWS 25-35 KT OF CROSS
BARRIER FLOW OVER SALISBURY RIDGE. THIS FLOW COMBINED WITH A LOW-
LEVEL INVERSION AND WIND REVERSAL ALOFT WILL FAVOR GUSTY NELY
WINDS IN DOWNTOWN JUNEAU AND S DOUGLAS THU AFTERNOON AND
NIGHT...WITH WINDS REMAINING ELEVATED AS SYNOPTIC SLYS SPREAD N
INTO THE AREA FRI MORNING. FARTHER S...PREVIOUSLY MENTIONED LLJ
TIED TO THE ADVANCING FRONTAL BOUNDARY WILL POSSIBLY YIELD GUSTS
UP TO 45 MPH OVER LAND ZONE 27 /CRAIG AND KLAWOCK AREA/.

UPPER TROUGH IS FORECAST TO PERSIST OVER THE GULF THROUGH THE
WEEKEND AND INTO EARLY/POSSIBLY MIDDLE OF NEXT WEEK. THIS WILL
LIKELY SUPPORT A PROLONGED PERIOD OF RAINY WEATHER. HOWEVER...DID
NOT ATTEMPT TO ADD A SUBSTANTIAL AMOUNT OF DETAIL TO THE FORECAST
DURING THESE LATER TIME PERIODS DUE TO INDIVIDUAL EPISODES OF RAIN
BEING TIED TO SMALL-SCALE/LOW PREDICTABILITY WAVES MOVING THROUGH
THE LARGE-SCALE TROUGH.

FORECAST CONFIDENCE IS ABOVE AVERAGE WITH REGARD TO WIDESPREAD
MARINE WIND HAZARDS THROUGH FRI. CONFIDENCE IN ONSET AND LOCATION
OF HEAVIEST PRECIPITATION IS AROUND AVERAGE. CONFIDENCE THEN FALLS
BELOW AVERAGE BY THE WEEKEND AND BEYOND.

&&

.AJK WATCHES/WARNINGS/ADVISORIES...
PUBLIC...NONE.
MARINE...GALE WARNING FOR PKZ042-043-052.
         SMALL CRAFT ADVISORY FOR PKZ012-013-031>033-041-051.

&&

$$

BEZENEK/GARNER

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







000
FXAK67 PAJK 302315
AFDAJK

SOUTHEAST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE JUNEAU AK
315 PM AKDT TUE SEP 30 2014

.SHORT TERM...THIS MORNINGS UPPER LEVEL LOW FROM THE NORTHEAST
GULF OF ALASKA CONTINUES TO JUMP MOST OF THE ENERGY IN TO
NORTHWEST BRITISH COLUMBIA. THERE REMAINS SOME ACTIVE HEAVIER
SHOWERS MOVING ACROSS THE NORTHERN PANHANDLE AND TOWARD BRITISH
COLUMBIA. SOME OF THESE HEAVIER SHOWERS THROUGH THE LATE AFTERNOON
HAVE BEEN SPARKING A FEW STRIKES OF LIGHTNING. DO NOT THINK THAT
THEY WILL CONTINUE MUCH MORE INTO THE EVENING.  SOUTHERN PANHANDLE
GETTING SOME ISOLATED SHOWERS THIS EVENING BUT MAJORITY AREA WAS
COVERED WITH LOWER CLOUD LEVELS.

THE REMAINS OF THE LOW WILL BE A TROUGH LYING ACROSS THE PANHANDLE
JUST SOUTH OF ICY STRAIT THIS EVENING THAT WILL BE MOVING SLOWLY
SOUTHWARD ACROSS THE PANHANDLE AND IS EXPECTED TO DISSIPATE NEAR
DIXON ENTRANCE WEDNESDAY. HIGH PRESSURE IS BUILDING OVER THE
ALASKAN INTERIOR AND YUKON TERRITORY. THIS IS EXPECTED TO INCREASE
THE NORTH GRADIENT AND OUTFLOW TONIGHT AND WEDNESDAY ACROSS THE
NORTH. THE COOLER AND DRIER HAS BEEN TRYING TO FILTER IN ALL DAY
ACROSS THE NORTH AND AS THE SHOWERS TAPER OFF AND END OVERNIGHT
LOOK FOR CLEARING TO START AND MOVE SOUTH AS WELL.

GALES FOR THE OFFSHORE WATERS AND TWO OF THE COASTAL ZONES TO
TAPER OFF TONIGHT WITH SMALL CRAFT WINDS AND SEAS FOR THE OUTER
WATER THROUGH MUCH OF WEDNESDAY. LYNN CANAL TO BE SMALL CRAFT FOR
WINDS TONIGHT AND WEDNESDAY FOR THE NORTH WINDS.

.LONG TERM...START OF THE LONG TERM WILL FEATURE A DRY CONTINENTAL
AIRMASS OVER SERN AK SUPPORTIVE OF A LARGE DIURNAL TEMPERATURE
SWING AS WED NIGHT TEMPERATURES IN THE 30S /POSSIBLY MID 20S INVOF
YAKUTAT/ WARM INTO THE UPPER 40S TO LOW 50S BY THU AFTERNOON.
ATTENTION QUICKLY TURNS TO AN UPPER TROUGH AND ASSOCIATED SURFACE
CYCLONE ENTERING THE GULF THU AFTERNOON AND NIGHT. A FRONTAL
BOUNDARY IS FORECAST TO ENTER THE SERN GULF AND FAR SRN PORTIONS
OF THE PANHANDLE THU NIGHT. STRONG WAA AND ISENTROPIC UPGLIDE WILL
DEVELOP ALONG AND N OF THE FRONT RESULTING IN THE DEVELOPMENT OF
RAIN QUICKLY SPREADING FROM SRN AREAS INTO CNTRL/NRN AREAS BY 12Z
FRI. BEST COMBINATION OF MOISTURE INFLUX AS WELL AS SYNOPTIC AND
OROGRAPHIC LIFT IS CURRENTLY FORECAST TO BE LOCATED OVER THE SRN
PANHANDLE...AND THUS WILL BE THE MOST PROBABLE LOCATION FOR HEAVY
RAINFALL.

DETERMINISTIC MODEL SOLUTIONS CONTINUE TO SHOW SUBSTANTIAL
VARIABILITY WITH THE EVOLUTION OF THE LOW OVER THE GULF. THE
ECMWF PRODUCES MULTIPLE LOW CENTERS...WHILE THE GFS AND GEM ARE
MORE CONSOLIDATED. THE GEM APPEARED TO BE A GOOD MIDDLE
GROUND...THUS USED THAT MODEL FOR A REFRESH OF PRESSURE FRI INTO
SAT MORNING BEFORE TRANSITIONING TO WPC GUIDANCE. DESPITE
DIFFERENCES IN SMALLER SCALE EVOLUTIONARY DETAILS...ALL GUIDANCE
IS IN AGREEMENT WITH THE DEVELOPMENT OF WIDESPREAD SMALL CRAFT AND
GALE FORCE WINDS FOR BOTH THE INNER CHANNELS AND OUTSIDE WATERS
THU THROUGH FRI. BORDERLINE STORM FORCE WINDS WILL BE POSSIBLE
OVER MARINE ZONES 41...42...43...AND 310 AS A 50-70 KT ELY LOW-
LEVEL JET LIFTS N THU AFTERNOON/NIGHT IMMEDIATELY AHEAD OF THE
FRONT. HIGH END GALE FORCE WINDS ALSO APPEAR PROBABLE OVER CROSS
SOUND.

ELSEWHERE...HIGHER RESOLUTION 12 KM NAM SHOWS 25-35 KT OF CROSS
BARRIER FLOW OVER SALISBURY RIDGE. THIS FLOW COMBINED WITH A LOW-
LEVEL INVERSION AND WIND REVERSAL ALOFT WILL FAVOR GUSTY NELY
WINDS IN DOWNTOWN JUNEAU AND S DOUGLAS THU AFTERNOON AND
NIGHT...WITH WINDS REMAINING ELEVATED AS SYNOPTIC SLYS SPREAD N
INTO THE AREA FRI MORNING. FARTHER S...PREVIOUSLY MENTIONED LLJ
TIED TO THE ADVANCING FRONTAL BOUNDARY WILL POSSIBLY YIELD GUSTS
UP TO 45 MPH OVER LAND ZONE 27 /CRAIG AND KLAWOCK AREA/.

UPPER TROUGH IS FORECAST TO PERSIST OVER THE GULF THROUGH THE
WEEKEND AND INTO EARLY/POSSIBLY MIDDLE OF NEXT WEEK. THIS WILL
LIKELY SUPPORT A PROLONGED PERIOD OF RAINY WEATHER. HOWEVER...DID
NOT ATTEMPT TO ADD A SUBSTANTIAL AMOUNT OF DETAIL TO THE FORECAST
DURING THESE LATER TIME PERIODS DUE TO INDIVIDUAL EPISODES OF RAIN
BEING TIED TO SMALL-SCALE/LOW PREDICTABILITY WAVES MOVING THROUGH
THE LARGE-SCALE TROUGH.

FORECAST CONFIDENCE IS ABOVE AVERAGE WITH REGARD TO WIDESPREAD
MARINE WIND HAZARDS THROUGH FRI. CONFIDENCE IN ONSET AND LOCATION
OF HEAVIEST PRECIPITATION IS AROUND AVERAGE. CONFIDENCE THEN FALLS
BELOW AVERAGE BY THE WEEKEND AND BEYOND.

&&

.AJK WATCHES/WARNINGS/ADVISORIES...
PUBLIC...NONE.
MARINE...GALE WARNING FOR PKZ042-043-052.
         SMALL CRAFT ADVISORY FOR PKZ012-013-031>033-041-051.

&&

$$

BEZENEK/GARNER

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







000
FXAK67 PAJK 302315
AFDAJK

SOUTHEAST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE JUNEAU AK
315 PM AKDT TUE SEP 30 2014

.SHORT TERM...THIS MORNINGS UPPER LEVEL LOW FROM THE NORTHEAST
GULF OF ALASKA CONTINUES TO JUMP MOST OF THE ENERGY IN TO
NORTHWEST BRITISH COLUMBIA. THERE REMAINS SOME ACTIVE HEAVIER
SHOWERS MOVING ACROSS THE NORTHERN PANHANDLE AND TOWARD BRITISH
COLUMBIA. SOME OF THESE HEAVIER SHOWERS THROUGH THE LATE AFTERNOON
HAVE BEEN SPARKING A FEW STRIKES OF LIGHTNING. DO NOT THINK THAT
THEY WILL CONTINUE MUCH MORE INTO THE EVENING.  SOUTHERN PANHANDLE
GETTING SOME ISOLATED SHOWERS THIS EVENING BUT MAJORITY AREA WAS
COVERED WITH LOWER CLOUD LEVELS.

THE REMAINS OF THE LOW WILL BE A TROUGH LYING ACROSS THE PANHANDLE
JUST SOUTH OF ICY STRAIT THIS EVENING THAT WILL BE MOVING SLOWLY
SOUTHWARD ACROSS THE PANHANDLE AND IS EXPECTED TO DISSIPATE NEAR
DIXON ENTRANCE WEDNESDAY. HIGH PRESSURE IS BUILDING OVER THE
ALASKAN INTERIOR AND YUKON TERRITORY. THIS IS EXPECTED TO INCREASE
THE NORTH GRADIENT AND OUTFLOW TONIGHT AND WEDNESDAY ACROSS THE
NORTH. THE COOLER AND DRIER HAS BEEN TRYING TO FILTER IN ALL DAY
ACROSS THE NORTH AND AS THE SHOWERS TAPER OFF AND END OVERNIGHT
LOOK FOR CLEARING TO START AND MOVE SOUTH AS WELL.

GALES FOR THE OFFSHORE WATERS AND TWO OF THE COASTAL ZONES TO
TAPER OFF TONIGHT WITH SMALL CRAFT WINDS AND SEAS FOR THE OUTER
WATER THROUGH MUCH OF WEDNESDAY. LYNN CANAL TO BE SMALL CRAFT FOR
WINDS TONIGHT AND WEDNESDAY FOR THE NORTH WINDS.

.LONG TERM...START OF THE LONG TERM WILL FEATURE A DRY CONTINENTAL
AIRMASS OVER SERN AK SUPPORTIVE OF A LARGE DIURNAL TEMPERATURE
SWING AS WED NIGHT TEMPERATURES IN THE 30S /POSSIBLY MID 20S INVOF
YAKUTAT/ WARM INTO THE UPPER 40S TO LOW 50S BY THU AFTERNOON.
ATTENTION QUICKLY TURNS TO AN UPPER TROUGH AND ASSOCIATED SURFACE
CYCLONE ENTERING THE GULF THU AFTERNOON AND NIGHT. A FRONTAL
BOUNDARY IS FORECAST TO ENTER THE SERN GULF AND FAR SRN PORTIONS
OF THE PANHANDLE THU NIGHT. STRONG WAA AND ISENTROPIC UPGLIDE WILL
DEVELOP ALONG AND N OF THE FRONT RESULTING IN THE DEVELOPMENT OF
RAIN QUICKLY SPREADING FROM SRN AREAS INTO CNTRL/NRN AREAS BY 12Z
FRI. BEST COMBINATION OF MOISTURE INFLUX AS WELL AS SYNOPTIC AND
OROGRAPHIC LIFT IS CURRENTLY FORECAST TO BE LOCATED OVER THE SRN
PANHANDLE...AND THUS WILL BE THE MOST PROBABLE LOCATION FOR HEAVY
RAINFALL.

DETERMINISTIC MODEL SOLUTIONS CONTINUE TO SHOW SUBSTANTIAL
VARIABILITY WITH THE EVOLUTION OF THE LOW OVER THE GULF. THE
ECMWF PRODUCES MULTIPLE LOW CENTERS...WHILE THE GFS AND GEM ARE
MORE CONSOLIDATED. THE GEM APPEARED TO BE A GOOD MIDDLE
GROUND...THUS USED THAT MODEL FOR A REFRESH OF PRESSURE FRI INTO
SAT MORNING BEFORE TRANSITIONING TO WPC GUIDANCE. DESPITE
DIFFERENCES IN SMALLER SCALE EVOLUTIONARY DETAILS...ALL GUIDANCE
IS IN AGREEMENT WITH THE DEVELOPMENT OF WIDESPREAD SMALL CRAFT AND
GALE FORCE WINDS FOR BOTH THE INNER CHANNELS AND OUTSIDE WATERS
THU THROUGH FRI. BORDERLINE STORM FORCE WINDS WILL BE POSSIBLE
OVER MARINE ZONES 41...42...43...AND 310 AS A 50-70 KT ELY LOW-
LEVEL JET LIFTS N THU AFTERNOON/NIGHT IMMEDIATELY AHEAD OF THE
FRONT. HIGH END GALE FORCE WINDS ALSO APPEAR PROBABLE OVER CROSS
SOUND.

ELSEWHERE...HIGHER RESOLUTION 12 KM NAM SHOWS 25-35 KT OF CROSS
BARRIER FLOW OVER SALISBURY RIDGE. THIS FLOW COMBINED WITH A LOW-
LEVEL INVERSION AND WIND REVERSAL ALOFT WILL FAVOR GUSTY NELY
WINDS IN DOWNTOWN JUNEAU AND S DOUGLAS THU AFTERNOON AND
NIGHT...WITH WINDS REMAINING ELEVATED AS SYNOPTIC SLYS SPREAD N
INTO THE AREA FRI MORNING. FARTHER S...PREVIOUSLY MENTIONED LLJ
TIED TO THE ADVANCING FRONTAL BOUNDARY WILL POSSIBLY YIELD GUSTS
UP TO 45 MPH OVER LAND ZONE 27 /CRAIG AND KLAWOCK AREA/.

UPPER TROUGH IS FORECAST TO PERSIST OVER THE GULF THROUGH THE
WEEKEND AND INTO EARLY/POSSIBLY MIDDLE OF NEXT WEEK. THIS WILL
LIKELY SUPPORT A PROLONGED PERIOD OF RAINY WEATHER. HOWEVER...DID
NOT ATTEMPT TO ADD A SUBSTANTIAL AMOUNT OF DETAIL TO THE FORECAST
DURING THESE LATER TIME PERIODS DUE TO INDIVIDUAL EPISODES OF RAIN
BEING TIED TO SMALL-SCALE/LOW PREDICTABILITY WAVES MOVING THROUGH
THE LARGE-SCALE TROUGH.

FORECAST CONFIDENCE IS ABOVE AVERAGE WITH REGARD TO WIDESPREAD
MARINE WIND HAZARDS THROUGH FRI. CONFIDENCE IN ONSET AND LOCATION
OF HEAVIEST PRECIPITATION IS AROUND AVERAGE. CONFIDENCE THEN FALLS
BELOW AVERAGE BY THE WEEKEND AND BEYOND.

&&

.AJK WATCHES/WARNINGS/ADVISORIES...
PUBLIC...NONE.
MARINE...GALE WARNING FOR PKZ042-043-052.
         SMALL CRAFT ADVISORY FOR PKZ012-013-031>033-041-051.

&&

$$

BEZENEK/GARNER

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






  [top]

000
FXAK68 PAFC 302151
AFDAFC

SOUTHCENTRAL AND SOUTHWEST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE ANCHORAGE AK
151 PM AKDT TUE SEP 30 2014

.ANALYSIS AND UPPER LEVELS...

SNOW SHOWERS ASSOCIATED WITH AN UPPER WAVE WERE EVIDENT ALONG THE
EASTERN ALASKA RANGE. LOW VFR CONDITIONS WITH STRATUS ASSOCIATED
WITH SUBSIDENCE WAS EVIDENT OVER THE KUSKOKWIM DELTA. THE
REMAINDER OF THE MAINLAND WAS UNDER FAIR SKIES WITH RELATIVELY
COOL AND DRY NORTHERLY FLOW. OUTFLOW WINDS ACROSS
SOUTHCENTRAL...ESPECIALLY THE GULF...PEAKED OVERNIGHT AND ARE ON
THE DECLINE. THE PINCH IN PRESSURE GRADIENT BETWEEN THE EASTERN
BERING RIDGE AND THE LOW COMPLEX OVER THE NORTH PACIFIC CONTINUED BRISK
EASTERLY WINDS ACROSS THE AK PEN...EAST ALEUTIANS/EASTERN BERING
SEA.

&&

.MODEL DISCUSSION...
ALOFT...MODELS HAVE SIMILAR PHASING OF THE TROUGH OVER THE
MAINLAND AND THE CUT-OFF LOW OVER THE NORTH PACIFIC. THIS SOLUTION
SEEMS REASONABLE AS COLD AIR SHOULD DIVE SOUTH ALONG THE FORWARD
SIDE OF AN AMPLIFYING UPPER RIDGE OVER THE EASTERN BERING SEA AND
SHARPEN THE MAINLAND TROUGH. THIS EFFECTIVELY PINCHES OFF THE
BERING SEA RIDGE ON THU AND CREATES A WEAKNESS IN THE HEIGHT
FIELDS WHICH ALLOWS THE NORTH PACIFIC CUT-OFF LOW TO PROGRESS
NORTH.

SURFACE FEATURES HOWEVER ARE MORE PROBLEMATIC WITH RESPECT TO
TIMING...INTENSITY...AND POSITION. OVERALL...THERE SHOULD BE A
FAIRLY STRONG TRIPLE POINT FEATURE SPAWNING OFF THE THE BAROCLINIC
ZONE ASSOCIATED WITH THE CUT-OFF OVER THE NORTH PACIFIC. ALL
MODELS SHOW A FAIRLY GOOD LEFT EXIT JET POSITION OVER THE DEVELOPING
TRIPLE POINT WHICH HEADS INTO THE NORTHERN GULF THU NIGHT/FRI
MORNING. THE 00Z NAM IS THE FASTEST IN MOVING THIS FEATURE NORTH
WITH THE GLOBAL MODELS SOMEWHAT SLOWER. THERE IS A GENERAL
CONSENSUS FOR A FAIRLY STRONG LOW OVER THE NORTHEASTERN GULF FRI.
FOR NOW WILL CONTINUE WITH OFFICIAL GRIDS WITH BLEND OF THE GEM
GLOBAL/GFS IN THE GULF KEEPING GALES WITH THIS FEATURE FOR NOW.
OUT WEST...MODELS HAVE SIMILAR HANDING OF FEATURES...SO IN GENERAL
WILL LEAN TOWARD THE GFS.

&&

.SHORT TERM FORECAST...

SOUTHCENTRAL ALASKA...
COOL AND DRY CONDITIONS WITH DIMINISHING WINDS ARE EXPECTED
ACROSS SOUTHCENTRAL OVER THE NEXT COUPLE OF DAYS. STRONG EASTERLY
WINDS AND INCREASED CLOUD COVER IN ADVANCE OF APPROACHING TRIPLE
POINT WILL START PUSHING TOWARD THE SOUTHERN GULF ON THU. GALES
WILL CONTINUE TO SPREAD NORTH WITH THE TRIPLE POINT ON THU NIGHT
AND LOCAL GAP FLOWS WILL DEVELOP ACROSS THE SOUTHERN MAINLAND WITH
INCREASING PRESSURE AND TEMP GRADIENTS. MOISTURE SHOULD SPREAD
INTO THE SOUTHEASTERN COPPER RIVER BASIN AND GULF COAST THU NIGHT
THEN SPREAD WEST ON FRI.  THE WESTWARD EXTENT OF THE MOISTURE
PUSH AND CHARACTER OF PRECIPITATION INLAND ON FRI IS STILL
UNCERTAIN WITH CURRENT MODELS DIFFERENCES. HOWEVER AT THIS
TIME...IT APPEARS THAT THE COAST WILL BE MAINLY RAIN AND THE
COPPER RIVER BASIN LIKELY WILL HAVE SNOW OR A MIX.

SOUTHWEST ALASKA...WHAT LITTLE STRATUS MOVED IN OVER THE DELTA
THIS MORNING SHOULD MOVE SOUTH AS THE NORTHERLY OFFSHORE
STRENGTHEN. EXPECT RELATIVELY DRY AND COOL CONDITIONS TO LAST
OVER THE NEXT COUPLE OF DAYS WITH RIDGING OVER THE MAINLAND AND
LOW PRESSURE IN THE GULF. ALSO EXPECT WINDS CONDITIONS TO PERSIST
AND EVEN STRENGTHEN SOME OVER THE AK PEN THROUGH THU. WILL ALSO
SEE SOME LOCALLY BRISK WINDS OVER BRISTOL BAY.

BERING SEA/ALEUTIANS...RAIN AND WIND WILL CONTINUE TO JUST BARELY
BRUSH THE ALEUTIAN ISLANDS AS THE LOW CONTINUES TO SLOWLY TRACK
TO THE EAST. OTHERWISE HIGH PRESSURE WILL BUILD OVER THE CENTRAL
BERING SEA AND CONTINUE TO STRENGTHEN THROUGH MID
WEEK...CONTINUING THE SPLIT-FLOW BLOCKING PATTERN AND PROVIDING
VERY QUIET CONDITIONS FOR MOST OF THE REGION.

&&

.LONG TERM FORECAST (SAT OCT 4 - TUE OCT 7)...

BEGINNING THE EXTENDED PERIOD SATURDAY...A HIGHLY AMPLIFIED
PATTERN WILL CONTINUE ACROSS THE REGION...WITH A BLOCKING RIDGE
EXTENDING FROM THE BERING NORTHWARD INTO SIBERIA...AND A LONGWAVE
TROUGH OVER THE STATE OF ALASKA. EVENTUALLY THE TROUGH WILL
DEVELOP INTO A CLOSED VORTEX ALOFT OVER SOUTHERN ALASKA AND WILL
REMAIN IN PLACE THROUGH TUESDAY. WHILE THERE WILL NOT BE A
SUBTROPICAL CONNECTION...WEAK DISTURBANCES ROTATING AROUND THE
PERIPHERY OF THE LOW WILL SUPPORT RAIN AND SNOW CHANCES ACROSS
PORTIONS OF SOUTHERN ALASKA MAINLY EAST OF THE ALASKA AND ALEUTIAN
RANGES. THE BEST CHANCES FOR RAIN...THEN SNOW...WILL BE ACROSS THE
COPPER BASIN. ARCTIC AIR WILL CONTINUE TO FILTER INTO SOUTHERN
ALASKA THROUGH THE WEEKEND...WITH GRADUALLY COOLING TEMPERATURES.
RIGHT NOW...THE COLDEST TEMPERATURES WILL LIKELY DEVELOP ON MONDAY
AND TUESDAY AS THE UPPER VORTEX SLOWLY TRANSLATES EAST AND COLDER
AIR AND CLEARER SKIES FORM ACROSS THE STATE.

- AHSENMACHER

&&

.AFC WATCHES/WARNINGS/ADVISORIES...
PUBLIC...NONE.
MARINE...150 155 172 174.
FIRE WEATHER...NONE.

&&

$$

RMC/AHSENMACHER SEP 14




000
FXAK68 PAFC 301346 AAA
AFDAFC

SOUTHCENTRAL AND SOUTHWEST ALASKA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE ANCHORAGE AK
546 AM AKDT TUE SEP 30 2014

ANALYSIS AND UPPER LEVELS...WATER VAPOR SATELLITE IMAGERY THIS
MORNING INDICATED THE ARCTIC TROUGH IN SOUTHERN ALASKA HAS CLOSED
OFF INTO A WEAK UPPER LEVEL CIRCULATION...WITH ASSOCIATED SURFACE
CIRCULATION MOVING QUICKLY INTO THE NORTHERN PANHANDLE. AS
EXPECTED...STRONG GAP FLOW AROUND PRINCE WILLIAM SOUND PEAKED
EARLIER THIS MORNING...WITH OBSERVATIONS SHOWING A STEADY DECLINE
IN THOSE WINDS AS THE TROUGH PUSHES OFF FURTHER TO THE EAST.
MEANWHILE...HIGH PRESSURE CONTINUES TO SLOWLY BUILD INTO FROM THE
WEST.

FURTHER WEST...AN UPPER RIDGE PERSISTS OVER THE NORTHERN BERING
SEA...WITH A VERTICALLY STACKED LOW NEARLY STATIONARY WELL SOUTH
OF THE ALEUTIANS. LIGHT RAIN AND GUSTY WINDS ON THE FRINGES OF
THIS SYSTEM ARE BEING OBSERVED ACROSS THE EASTERN HALF OF THE
ALEUTIAN CHAIN.

&&

MODEL DISCUSSION...THE MODELS REMAIN IN GOOD SYNOPTIC AGREEMENT AT
BOTH THE SURFACE AND UPPER LEVELS THROUGHOUT MUCH OF THE SHORT-
TERM (84 HOUR) FORECAST PERIOD. HOWEVER...DIFFERENCES DO ARISE
EARLY THURSDAY MORNING SOUTH OF THE GULF WITH THE HANDLING OF THE
NEXT LOW COMPLEX. THE MODELS GENERALLY SHOW THE REMNANTS OF AN OLD
TROPICAL SYSTEM (KAMMURI) WITH AMPLE MOISTURE BECOMING ABSORBED BY
THE LOW CURRENTLY SOUTH OF THE CENTRAL ALEUTIANS. AS EXPECTED THE
MODELS CONTINUE TO STRUGGLE WITH THIS COMPLEX SYSTEM AS IT TRACKS
SLOWLY NORTHEASTWARD TOWARD THE SOUTHERN GULF. THE FORECAST
CHALLENGE WITH THIS SYSTEM WILL BE IF AND WHERE A TRIPLE POINT
CIRCULATION FORMS ON THURSDAY...AND HOW DEEP/STRONG IT WILL GET.
WITH THIS BEING AT THE END OF THE SHORT TERM AND HAVING SUCH MODEL
SPREAD AT THAT TIME FRAME...FORECAST CONFIDENCE REMAINS LOW
REGARDING THE KEY DETAILS OF THIS EVOLUTION. THE GEM GLOBAL WAS
THE PREFERRED SOLUTION OVERALL WITH THIS SYSTEM AND IS FAIRLY
CLOSE TO THE GFS ENSEMBLE MEAN AND WPC SOLUTIONS.

PRIOR TO 60 HOURS...THE NAM WAS MAINLY UTILIZED OVER THE EAST
DOMAIN TO CONTINUE CAPTURING THE ONGOING GAP WINDS. THE ECMWF
SOLUTION WAS PREFERRED OVER THE WESTERN DOMAIN FOR THE MORNING
PACKAGE FOR SUPERIOR RUN-TO-RUN CONSISTENCY.

&&

.SHORT TERM FORECAST...
SOUTHCENTRAL ALASKA...SUBSIDENCE BEHIND THE DEPARTING UPPER LEVEL
WAVE COUPLED WITH TIGHT PRESSURE GRADIENTS LED TO GUSTY
CONDITIONS AND STRONG GAP FLOW OVER PRINCE WILLIAM SOUND AND PARTS
OF SOUTHCENTRAL OVERNIGHT. WINDS HAVE NOW PEAKED AT MANY
LOCATIONS...AND WILL GRADUALLY DIMINISH THROUGHOUT THE DAY TODAY
AS THE UPPER LEVEL TROUGH CONTINUES TO MOVE AWAY. PRECIPITATION
ASSOCIATED WITH THIS FEATURE IS LIMITED TO THE FAR EASTERN COPPER
RIVER BASIN...AND EVEN THIS WILL RAPIDLY DIMINISH BY LATER THIS
MORNING AS COLDER AND DRIER AIR MOVES IN FROM THE WEST.

SOUTHWEST ALASKA...CONDITIONS WILL BE RELATIVELY DRY ACROSS
THE SOUTHWEST MAINLAND OVER THE NEXT COUPLE OF DAYS AS HIGH
PRESSURE REMAINS OVER THE AREA. AN ONSHORE COMPONENT OF THE WINDS
ACROSS THE KUSKOKWIM DELTA WILL KEEP THE POTENTIAL FOR A LITTLE
FOG AROUND THE AREA THROUGH THIS EVENING. HOWEVER...INCREASINGLY
OFFSHORE FLOW BY LATE THIS AFTERNOON WILL LIKELY HAMPER ANY FOG
FORMATION/ADVECTION OVER THE MAJORITY OF THE AREA OVER THE NEXT
DAY OR SO. MEANWHILE...BRISK (BUT MOSTLY DRY) EASTERLY FLOW
ASSOCIATED WITH A LOW COMPLEX OVER THE NORTH PACIFIC WILL CONTINUE
ACROSS THE AK PEN THROUGH WED.

BERING SEA/ALEUTIANS...RAIN AND WIND WILL CONTINUE TO JUST BARELY
BRUSH THE ALEUTIAN ISLANDS AS THE LOW CONTINUES TO SLOWLY TRACK
TO THE EAST. OTHERWISE HIGH PRESSURE WILL BUILD OVER THE CENTRAL
BERING SEA AND CONTINUE TO STRENGTHEN THROUGH MID
WEEK...CONTINUING THE SPLIT-FLOW BLOCKING PATTERN AND PROVIDING
VERY QUIET CONDITIONS FOR MOST OF THE REGION.

&&

.LONG TERM FORECAST (FRI OCT 3 - MON OCT 6)...

ON FRIDAY...A HIGHLY AMPLIFIED PATTERN WILL BE DEVELOPING ACROSS
THE REGION...WITH A BLOCKING RIDGE ACROSS THE CENTRAL BERING
EXTENDING INTO SIBERIA...AND A LARGE TROUGH ACROSS THE MAINLAND.
ARCTIC AIR WILL ACCOMPANY THE TROUGH...WITH STEADILY DROPPING
TEMPERATURES HEADING INTO THE WEEKEND. THE PATTERN WILL GENERALLY
BE DRY...BUT THERE IS THE THREAT FOR SNOW AND SNOW SHOWERS ACROSS
MOST OF SOUTHCENTRAL BY THE WEEKEND...ESPECIALLY ACROSS THE COPPER
BASIN. THERE REMAINS UNCERTAINTY WITH A LOW MOVING THROUGH THE
EASTERN GULF OF ALASKA...SO A CONSERVATIVE MIDDLE GROUND APPROACH
WAS TAKEN WITH THE PRECIPITATION FORECAST. BY MONDAY...UNCERTAINTY
IN THE PATTERN GROWS IN MAGNITUDE QUICKLY AS THE TRACK OF
NORTHWEST PACIFIC CYCLONES (POSSIBLY INCLUDING RECURVING REMNANTS
OF PACIFIC TROPICAL CYCLONES) MOVING INTO THE BERING BECOMES
HIGHLY ERRATIC...THUS RESULTING IN SYNOPTIC SCALE DISAGREEMENT
AMONG THE VARIOUS GLOBAL NUMERICAL MODELS. WITH THAT SAID...THE
COLDEST TEMPS OF THE FALL CAN BE EXPECTED BY THIS WEEKEND.


&&


.AFC WATCHES/WARNINGS/ADVISORIES...
PUBLIC...NONE.
MARINE...GALE WARNING...119 127 128 150 155 172 174.
FIRE WEATHER...NONE.

&&

$$

TP SEP 14




000
FXAK68 PAFC 301346 AAA
AFDAFC

SOUTHCENTRAL AND SOUTHWEST ALASKA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE ANCHORAGE AK
546 AM AKDT TUE SEP 30 2014

ANALYSIS AND UPPER LEVELS...WATER VAPOR SATELLITE IMAGERY THIS
MORNING INDICATED THE ARCTIC TROUGH IN SOUTHERN ALASKA HAS CLOSED
OFF INTO A WEAK UPPER LEVEL CIRCULATION...WITH ASSOCIATED SURFACE
CIRCULATION MOVING QUICKLY INTO THE NORTHERN PANHANDLE. AS
EXPECTED...STRONG GAP FLOW AROUND PRINCE WILLIAM SOUND PEAKED
EARLIER THIS MORNING...WITH OBSERVATIONS SHOWING A STEADY DECLINE
IN THOSE WINDS AS THE TROUGH PUSHES OFF FURTHER TO THE EAST.
MEANWHILE...HIGH PRESSURE CONTINUES TO SLOWLY BUILD INTO FROM THE
WEST.

FURTHER WEST...AN UPPER RIDGE PERSISTS OVER THE NORTHERN BERING
SEA...WITH A VERTICALLY STACKED LOW NEARLY STATIONARY WELL SOUTH
OF THE ALEUTIANS. LIGHT RAIN AND GUSTY WINDS ON THE FRINGES OF
THIS SYSTEM ARE BEING OBSERVED ACROSS THE EASTERN HALF OF THE
ALEUTIAN CHAIN.

&&

MODEL DISCUSSION...THE MODELS REMAIN IN GOOD SYNOPTIC AGREEMENT AT
BOTH THE SURFACE AND UPPER LEVELS THROUGHOUT MUCH OF THE SHORT-
TERM (84 HOUR) FORECAST PERIOD. HOWEVER...DIFFERENCES DO ARISE
EARLY THURSDAY MORNING SOUTH OF THE GULF WITH THE HANDLING OF THE
NEXT LOW COMPLEX. THE MODELS GENERALLY SHOW THE REMNANTS OF AN OLD
TROPICAL SYSTEM (KAMMURI) WITH AMPLE MOISTURE BECOMING ABSORBED BY
THE LOW CURRENTLY SOUTH OF THE CENTRAL ALEUTIANS. AS EXPECTED THE
MODELS CONTINUE TO STRUGGLE WITH THIS COMPLEX SYSTEM AS IT TRACKS
SLOWLY NORTHEASTWARD TOWARD THE SOUTHERN GULF. THE FORECAST
CHALLENGE WITH THIS SYSTEM WILL BE IF AND WHERE A TRIPLE POINT
CIRCULATION FORMS ON THURSDAY...AND HOW DEEP/STRONG IT WILL GET.
WITH THIS BEING AT THE END OF THE SHORT TERM AND HAVING SUCH MODEL
SPREAD AT THAT TIME FRAME...FORECAST CONFIDENCE REMAINS LOW
REGARDING THE KEY DETAILS OF THIS EVOLUTION. THE GEM GLOBAL WAS
THE PREFERRED SOLUTION OVERALL WITH THIS SYSTEM AND IS FAIRLY
CLOSE TO THE GFS ENSEMBLE MEAN AND WPC SOLUTIONS.

PRIOR TO 60 HOURS...THE NAM WAS MAINLY UTILIZED OVER THE EAST
DOMAIN TO CONTINUE CAPTURING THE ONGOING GAP WINDS. THE ECMWF
SOLUTION WAS PREFERRED OVER THE WESTERN DOMAIN FOR THE MORNING
PACKAGE FOR SUPERIOR RUN-TO-RUN CONSISTENCY.

&&

.SHORT TERM FORECAST...
SOUTHCENTRAL ALASKA...SUBSIDENCE BEHIND THE DEPARTING UPPER LEVEL
WAVE COUPLED WITH TIGHT PRESSURE GRADIENTS LED TO GUSTY
CONDITIONS AND STRONG GAP FLOW OVER PRINCE WILLIAM SOUND AND PARTS
OF SOUTHCENTRAL OVERNIGHT. WINDS HAVE NOW PEAKED AT MANY
LOCATIONS...AND WILL GRADUALLY DIMINISH THROUGHOUT THE DAY TODAY
AS THE UPPER LEVEL TROUGH CONTINUES TO MOVE AWAY. PRECIPITATION
ASSOCIATED WITH THIS FEATURE IS LIMITED TO THE FAR EASTERN COPPER
RIVER BASIN...AND EVEN THIS WILL RAPIDLY DIMINISH BY LATER THIS
MORNING AS COLDER AND DRIER AIR MOVES IN FROM THE WEST.

SOUTHWEST ALASKA...CONDITIONS WILL BE RELATIVELY DRY ACROSS
THE SOUTHWEST MAINLAND OVER THE NEXT COUPLE OF DAYS AS HIGH
PRESSURE REMAINS OVER THE AREA. AN ONSHORE COMPONENT OF THE WINDS
ACROSS THE KUSKOKWIM DELTA WILL KEEP THE POTENTIAL FOR A LITTLE
FOG AROUND THE AREA THROUGH THIS EVENING. HOWEVER...INCREASINGLY
OFFSHORE FLOW BY LATE THIS AFTERNOON WILL LIKELY HAMPER ANY FOG
FORMATION/ADVECTION OVER THE MAJORITY OF THE AREA OVER THE NEXT
DAY OR SO. MEANWHILE...BRISK (BUT MOSTLY DRY) EASTERLY FLOW
ASSOCIATED WITH A LOW COMPLEX OVER THE NORTH PACIFIC WILL CONTINUE
ACROSS THE AK PEN THROUGH WED.

BERING SEA/ALEUTIANS...RAIN AND WIND WILL CONTINUE TO JUST BARELY
BRUSH THE ALEUTIAN ISLANDS AS THE LOW CONTINUES TO SLOWLY TRACK
TO THE EAST. OTHERWISE HIGH PRESSURE WILL BUILD OVER THE CENTRAL
BERING SEA AND CONTINUE TO STRENGTHEN THROUGH MID
WEEK...CONTINUING THE SPLIT-FLOW BLOCKING PATTERN AND PROVIDING
VERY QUIET CONDITIONS FOR MOST OF THE REGION.

&&

.LONG TERM FORECAST (FRI OCT 3 - MON OCT 6)...

ON FRIDAY...A HIGHLY AMPLIFIED PATTERN WILL BE DEVELOPING ACROSS
THE REGION...WITH A BLOCKING RIDGE ACROSS THE CENTRAL BERING
EXTENDING INTO SIBERIA...AND A LARGE TROUGH ACROSS THE MAINLAND.
ARCTIC AIR WILL ACCOMPANY THE TROUGH...WITH STEADILY DROPPING
TEMPERATURES HEADING INTO THE WEEKEND. THE PATTERN WILL GENERALLY
BE DRY...BUT THERE IS THE THREAT FOR SNOW AND SNOW SHOWERS ACROSS
MOST OF SOUTHCENTRAL BY THE WEEKEND...ESPECIALLY ACROSS THE COPPER
BASIN. THERE REMAINS UNCERTAINTY WITH A LOW MOVING THROUGH THE
EASTERN GULF OF ALASKA...SO A CONSERVATIVE MIDDLE GROUND APPROACH
WAS TAKEN WITH THE PRECIPITATION FORECAST. BY MONDAY...UNCERTAINTY
IN THE PATTERN GROWS IN MAGNITUDE QUICKLY AS THE TRACK OF
NORTHWEST PACIFIC CYCLONES (POSSIBLY INCLUDING RECURVING REMNANTS
OF PACIFIC TROPICAL CYCLONES) MOVING INTO THE BERING BECOMES
HIGHLY ERRATIC...THUS RESULTING IN SYNOPTIC SCALE DISAGREEMENT
AMONG THE VARIOUS GLOBAL NUMERICAL MODELS. WITH THAT SAID...THE
COLDEST TEMPS OF THE FALL CAN BE EXPECTED BY THIS WEEKEND.


&&


.AFC WATCHES/WARNINGS/ADVISORIES...
PUBLIC...NONE.
MARINE...GALE WARNING...119 127 128 150 155 172 174.
FIRE WEATHER...NONE.

&&

$$

TP SEP 14



000
FXAK67 PAJK 301342
AFDAJK

SOUTHEAST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE JUNEAU AK
542 AM AKDT TUE SEP 30 2014

.SHORT TERM...THE MAIN THEME OF THE SHORT RANGE FORECAST TODAY IS
CHANGE AS WE SEE THE BEGINNINGS OF THE FIRST COOL AIR MASS OF THE
FALL START TO DESCEND OVER THE NORTHERN PANHANDLE. BUT FIRST WE
HAVE TO DEAL WITH THE UPPER TROUGH THAT IS DRAGGING THE COOL AIR
DOWN IN THE FIRST PLACE. THE TROUGH IS CURRENTLY JUST EXITING
EASTERN INTERIOR ALASKA AND HEADING INTO THE WESTERN YUKON WITH
THE SOUTHERN END OF IT EXTENDING INTO THE NORTHERN GULF. A 80 KT
JET STREAK AT 500 MB THAT IS ROUNDING THE SOUTH SIDE OF THE TROUGH
IS NOT ONLY KEEPING THE TROUGH DEEP BUT ITS LEFT EXIT REGION HAS
HELPED FORM A 1002 MB SURFACE LOW OVER THE NORTHERN GULF AND
SPARKED OFF SOME SHOWERS AND THUNDERSTORMS OVER THE NORTHERN GULF
AND GULF COAST OVERNIGHT. THE AMOUNT OF LIGHTNING DETECTED IN THAT
AREA HAS DIMINISHED IN NUMBER OVER THE LAST HOUR OR TWO AS THE JET
STREAK MOVES E. SPEAKING OF WIND THERE IS A DECENT BAND OF GALE
FORCE WINDS IN THE GULF JUST SOUTH OF THE LOW AS WELL THIS
MORNING. AS FOR THE REST OF THE PANHANDLE, LOW CLOUDS, SOME FOG,
AND SOME PASSING SHOWERS ARE THE RULE OF THE MORNING.

THE TROUGH WILL MAKE ITS WAY SOUTHEASTWARD THROUGH TODAY AND
TONIGHT SPREADING RAIN SHOWERS AS IT COMES. MORE VIGOROUS SHOWERS
WILL BE STARTING UP IN THE NORTHERN PANHANDLE THIS MORNING WITH
THE SOUTHERN PANHANDLE STARTING TO GET IT THIS AFTERNOON. THIS
TROUGH SHOULD BE IN THE SOUTHERN PANHANDLE BY LATE TONIGHT ENDING
THE RAIN FOR THE NORTH BY THEN. TEMPERATURES ALOFT WITH THIS
TROUGH ARE RATHER COLD (AROUND -30 C). THAT COMBINED WITH THE
STILL PRESENT JET STREAK AND SOME UPPER VORTICITY COULD KEEP THE
POSSIBILITY OF SOME THUNDERSTORMS POPPING VALID. AS SUCH STILL
HAVE SLIGHT CHANCE OF THUNDERSTORMS UP FOR THE NEAR OUTER COASTAL
AREAS OF THE NORTHERN PANHANDLE AND THE NEAR SHORE WATERS OF THE
GULF TODAY. DECIDED TO NOT EXTEND IT INTO TONIGHT AS THE TROUGH
WILL HAVE WEAKENED SOMEWHAT AND THE MAIN FORCING WILL NO LONGER BE
OVER THE WARM WATERS OF THE GULF.

AS THE TROUGH MOVES SE THE WINDS IN THE GULF WILL START TO
DIMINISH. WESTERLY GALES WILL STILL BE PRESENT THROUGH TODAY BUT
SHOULD START TO DIMINISH TONIGHT DROPPING BELOW SMALL CRAFT BY
LATE TONIGHT. AS FOR INNER CHANNEL WINDS MOST PLACES WILL BE
STARTING OUT WITH EITHER W OR S WIND DIRECTIONS DEPENDING ON THE
LOCATION. WITH THE PRESSURE GRADIENTS AHEAD OF THE TROUGH SOME
AREAS LIKE LYNN CANAL HAVE JUMPED UP TO A SOUTHERLY SMALL CRAFT
THIS MORNING. THESE HIGHER WINDS WILL TRANSITION SOUTHWARD THROUGH
TODAY AND MOST AREAS WILL START TO SHIFT TO N AS THE TROUGH MOVES
BY. THE NORTHERN PANHANDLE WILL SEE THIS SHIFT SOMETIME THIS
AFTERNOON WHILE AREAS FARTHER SOUTH WILL HAVE TO WAIT TILL
SOMETIME TONIGHT.

BEHIND THE TROUGH THINGS RAPIDLY DRY AND CLEAR OUT AS A COOL AIR
MASS MAKES ITS WAY OUT OF THE ALASKA INTERIOR. YAKUTAT WILL LIKELY
HAVE A PARTLY CLOUDY BUT COOL NIGHT. AREAS IN THE NORTHERN HALF OF
THE PANHANDLE WILL SEE DIMINISHING CLOUDS TONIGHT. AS SUCH
OVERNIGHT LOWS WILL DROP INTO THE 30S ACROSS MUCH OF THE NORTHERN
PANHANDLE AND MAY GET BELOW FREEZING IN YAKUTAT AND WHITE PASS
AREA. ALSO WHILE THIS AIR MASS IS COMING FROM THE ARCTIC IT IS
NOT BITTERLY COLD AS WE ARE STILL EARLY IN THE SEASON. STILL IT HAS
ENOUGH PUNCH THAT NORTHERLY OUTFLOW WINDS WILL START UP ACROSS THE
NORTHERN PANHANDLE TONIGHT DUE TO PRESSURE GRADIENT ALONE. HOWEVER
THE COOL AIR POOLING IN THE YUKON DOES NOT APPEAR TO BE DEEP
ENOUGH TO GET OVER THE MOUNTAIN PASSES YET. SO NORTHERLY
WINDS IN THE CANAL ARE ONLY EXPECTED TO REACH 30 KT TONIGHT AND
SOME GUSTS TO 35 KT ARE EXPECTED IN DISENCHANTMENT BAY. OTHERWISE
MOST OTHER AREAS WILL ONLY SEE WINDS OF 20 KT OR LESS BY LATE
TONIGHT.

SHORT RANGE MODELS WERE IN DECENT AGREEMENT BUT DID DIFFER ON THE
SURFACE LOW IN THE NORTHERN GULF. NAM AND ECMWF SEEMED TO HAVE A
GOOD HANDLE ON LOW POSITION AND STRENGTH. THE GFS WAS A BIT TOO
FAR E WITH IT AND THE GEM JUST JUST A BIT TOO WEAK COMPARED TO
SURFACE OBS. FOR WINDS GEM AND NAM SEEMED TO HAVE SPEEDS DOWN
WHILE OTHER MODELS WERE JUST A LITTLE WEAK COMPARED TO SOME OBS.
OVERALL FEW CHANGES IN THE SHORT RANGE WITH THE MOST NOTICEABLE
CHANGES BEING STRENGTHEN THE OUTFLOW WINDS A BIT TONIGHT.

.LONG TERM...REMNANTS OF FAST MOVING CLIPPER LOW WILL CROSS FROM
THE SOUTHERN PANHANDLE INTO BRITISH COLUMBIA WEDNESDAY MORNING
WITH SOME LINGERING SHOWERS NEAR HYDER. SURFACE HIGH PRESSURE THAT
IS BUILDING OVER THE YUKON UNDER AN UPPER LEVEL TROUGH WILL TRACK
SOUTHEASTWARD BRINGING DRY CONDITIONS AND MOSTLY CLEAR SKIES TO
THE PANHANDLE. OFFSHORE FLOW BETWEEN THIS AREA OF HIGH PRESSURE
AND A LOW MOVING INTO THE AK GULF WILL BEGIN TO INCREASE LATE
WEDNESDAY NIGHT INTO THURSDAY. THIS NEXT LOW HAS POTENTIAL TO BE A
SIGNIFICANT SYSTEM PRODUCING STRONG WINDS AND SUBSTANTIAL
PRECIPITATION. AS THIS ADVANCING LOW STRENGTHENS OUTFLOW WINDS
WILL INCREASE AS THE PRESSURE GRADIENT TIGHTENS. WINDS OVER THE AK
GULF WILL ALSO INCREASE UP TO GALE FORCE AS THE FRONTAL BOUNDARIES
ASSOCIATED WITH THE LOW MOVE IN. BY THURSDAY NIGHT THE FRONT WILL
MOVE OVER THE PANHANDLE FORM SOUTH TO NORTH WITH WINDS CONTINUING
TO INCREASE. STRONGEST WINDS WILL BE ALONG EAST-WEST ORIENTED
CHANNELS, OVER COASTAL AREAS AND OUT OF INTERIOR PASSES. GUSTS UP
TO 50 MPH ARE NOT OUT OF THE QUESTION.

AFTER THE DRY WEDNESDAY AND WEDNESDAY NIGHT MORE WET WEATHER
RETURNS AND WILL REMAIN THROUGH THE WEEKEND. AS THIS INCOMING
SYSTEM INCORPORATES THE REMAINS OF TROPICAL STORM KUMMARI IT WILL
PROVIDE AMPLE MOISTURE WITH POTENTIAL FOR HEAVY RAIN STARTING
THURSDAY NIGHT INTO FRIDAY. PRECIP WILL TAPER OFF BY THE END OF
THE WEEKEND AS THE LOW FILLS AND STARTS TO EXIT THE REGION. THE
UPPER LEVEL TROUGH MOVING OVER THE PANHANDLE ON WEDNESDAY MOVES
COLD AIR MASS IN FROM THE YUKON OVER PANHANDLE WITH 850 MB TEMPS
IN THE -2 TO -6 C RANGE. CLEAR SKIES MAY PROVIDE ENOUGH INSOLATION
FOR DAY TIME TEMPS TO RISE INTO THE MID 50S. OVERNIGHT LOWS WILL
BE IN TO UPPER 20 TO LOW 30S FOR THE CENTRAL AND NORTHERN
PANHANDLE AND THE UPPER 30S TO LOW 40S FOR THE SOUTH DUE TO NOT
ONLY THE COLD UPPER LEVEL AIR BUT ALSO RADIATIONAL COOLING
RESULTING FROM CLEAR SKIES. TEMPERATURES WILL RETURN TO SEASONAL
NORMALS WITH THE ADVANCING FRONT WITH MOST PRECIP FALLING AS RAIN
BUT THERE MAY BE ENOUGH COLD AIR AT HIGHER ELEVATIONS TO PRODUCE
SNOW.

MODELS HAD GOOD CONSENSUS ON SYNOPTIC PATTERN THROUGH EARLY
THURSDAY BUT WITH LARGER MODEL SPECTRUM FOR TEMPERATURES. LEFT
GRIDS THROUGH WEDNESDAY MOSTLY AS IS DUE TO SIMILARITY TO NEW
MODEL RUNS WITH SOME LOWER TEMPS WEDNESDAY NIGHT. THE ADVANCING
SYSTEM FOR LATE IN THE WEEK BECAME MORE OF AN ISSUE. PREVIOUSLY
THE GEM HAD BEEN MODEL OF CHOICE DUE TO ITS CONSISTENCY, BUT THE
NEWEST RUN SHIFTED IN POSITION AND MORE SIGNIFICANTLY STRENGTH BY
DROPPING THE LOW CENTER TO 975 MB. THE GEM/ECMWF WERE CLOSER IN
STRENGTH WITH WEAKER GFS/NAM BUT THE GEM/GFS WERE CLOSER WITH
POSITION OF THE LOW WITH ECMWF/NAM FURTHER WEST. FOR NOW BUMPED UP
WINDS IN ANTICIPATION OF A DEEPER LOW BUT HELD OFF ON CHANGING THE
LOW POSITION UNTIL MODELS COME TO A BETTER CONSENSUS. FORECAST
CONFIDENCE IS AVERAGE FOR INTO WEDNESDAY NIGHT THEN IS WELL BELOW
AVERAGE STARTING THURSDAY.


&&

.AJK WATCHES/WARNINGS/ADVISORIES...
PUBLIC...NONE.
MARINE...GALE WARNING FOR PKZ043-052.
         SMALL CRAFT ADVISORY FOR PKZ012-013-022-033-036-041-042-051.

&&

$$

EAL/PRB

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








000
FXAK67 PAJK 301342
AFDAJK

SOUTHEAST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE JUNEAU AK
542 AM AKDT TUE SEP 30 2014

.SHORT TERM...THE MAIN THEME OF THE SHORT RANGE FORECAST TODAY IS
CHANGE AS WE SEE THE BEGINNINGS OF THE FIRST COOL AIR MASS OF THE
FALL START TO DESCEND OVER THE NORTHERN PANHANDLE. BUT FIRST WE
HAVE TO DEAL WITH THE UPPER TROUGH THAT IS DRAGGING THE COOL AIR
DOWN IN THE FIRST PLACE. THE TROUGH IS CURRENTLY JUST EXITING
EASTERN INTERIOR ALASKA AND HEADING INTO THE WESTERN YUKON WITH
THE SOUTHERN END OF IT EXTENDING INTO THE NORTHERN GULF. A 80 KT
JET STREAK AT 500 MB THAT IS ROUNDING THE SOUTH SIDE OF THE TROUGH
IS NOT ONLY KEEPING THE TROUGH DEEP BUT ITS LEFT EXIT REGION HAS
HELPED FORM A 1002 MB SURFACE LOW OVER THE NORTHERN GULF AND
SPARKED OFF SOME SHOWERS AND THUNDERSTORMS OVER THE NORTHERN GULF
AND GULF COAST OVERNIGHT. THE AMOUNT OF LIGHTNING DETECTED IN THAT
AREA HAS DIMINISHED IN NUMBER OVER THE LAST HOUR OR TWO AS THE JET
STREAK MOVES E. SPEAKING OF WIND THERE IS A DECENT BAND OF GALE
FORCE WINDS IN THE GULF JUST SOUTH OF THE LOW AS WELL THIS
MORNING. AS FOR THE REST OF THE PANHANDLE, LOW CLOUDS, SOME FOG,
AND SOME PASSING SHOWERS ARE THE RULE OF THE MORNING.

THE TROUGH WILL MAKE ITS WAY SOUTHEASTWARD THROUGH TODAY AND
TONIGHT SPREADING RAIN SHOWERS AS IT COMES. MORE VIGOROUS SHOWERS
WILL BE STARTING UP IN THE NORTHERN PANHANDLE THIS MORNING WITH
THE SOUTHERN PANHANDLE STARTING TO GET IT THIS AFTERNOON. THIS
TROUGH SHOULD BE IN THE SOUTHERN PANHANDLE BY LATE TONIGHT ENDING
THE RAIN FOR THE NORTH BY THEN. TEMPERATURES ALOFT WITH THIS
TROUGH ARE RATHER COLD (AROUND -30 C). THAT COMBINED WITH THE
STILL PRESENT JET STREAK AND SOME UPPER VORTICITY COULD KEEP THE
POSSIBILITY OF SOME THUNDERSTORMS POPPING VALID. AS SUCH STILL
HAVE SLIGHT CHANCE OF THUNDERSTORMS UP FOR THE NEAR OUTER COASTAL
AREAS OF THE NORTHERN PANHANDLE AND THE NEAR SHORE WATERS OF THE
GULF TODAY. DECIDED TO NOT EXTEND IT INTO TONIGHT AS THE TROUGH
WILL HAVE WEAKENED SOMEWHAT AND THE MAIN FORCING WILL NO LONGER BE
OVER THE WARM WATERS OF THE GULF.

AS THE TROUGH MOVES SE THE WINDS IN THE GULF WILL START TO
DIMINISH. WESTERLY GALES WILL STILL BE PRESENT THROUGH TODAY BUT
SHOULD START TO DIMINISH TONIGHT DROPPING BELOW SMALL CRAFT BY
LATE TONIGHT. AS FOR INNER CHANNEL WINDS MOST PLACES WILL BE
STARTING OUT WITH EITHER W OR S WIND DIRECTIONS DEPENDING ON THE
LOCATION. WITH THE PRESSURE GRADIENTS AHEAD OF THE TROUGH SOME
AREAS LIKE LYNN CANAL HAVE JUMPED UP TO A SOUTHERLY SMALL CRAFT
THIS MORNING. THESE HIGHER WINDS WILL TRANSITION SOUTHWARD THROUGH
TODAY AND MOST AREAS WILL START TO SHIFT TO N AS THE TROUGH MOVES
BY. THE NORTHERN PANHANDLE WILL SEE THIS SHIFT SOMETIME THIS
AFTERNOON WHILE AREAS FARTHER SOUTH WILL HAVE TO WAIT TILL
SOMETIME TONIGHT.

BEHIND THE TROUGH THINGS RAPIDLY DRY AND CLEAR OUT AS A COOL AIR
MASS MAKES ITS WAY OUT OF THE ALASKA INTERIOR. YAKUTAT WILL LIKELY
HAVE A PARTLY CLOUDY BUT COOL NIGHT. AREAS IN THE NORTHERN HALF OF
THE PANHANDLE WILL SEE DIMINISHING CLOUDS TONIGHT. AS SUCH
OVERNIGHT LOWS WILL DROP INTO THE 30S ACROSS MUCH OF THE NORTHERN
PANHANDLE AND MAY GET BELOW FREEZING IN YAKUTAT AND WHITE PASS
AREA. ALSO WHILE THIS AIR MASS IS COMING FROM THE ARCTIC IT IS
NOT BITTERLY COLD AS WE ARE STILL EARLY IN THE SEASON. STILL IT HAS
ENOUGH PUNCH THAT NORTHERLY OUTFLOW WINDS WILL START UP ACROSS THE
NORTHERN PANHANDLE TONIGHT DUE TO PRESSURE GRADIENT ALONE. HOWEVER
THE COOL AIR POOLING IN THE YUKON DOES NOT APPEAR TO BE DEEP
ENOUGH TO GET OVER THE MOUNTAIN PASSES YET. SO NORTHERLY
WINDS IN THE CANAL ARE ONLY EXPECTED TO REACH 30 KT TONIGHT AND
SOME GUSTS TO 35 KT ARE EXPECTED IN DISENCHANTMENT BAY. OTHERWISE
MOST OTHER AREAS WILL ONLY SEE WINDS OF 20 KT OR LESS BY LATE
TONIGHT.

SHORT RANGE MODELS WERE IN DECENT AGREEMENT BUT DID DIFFER ON THE
SURFACE LOW IN THE NORTHERN GULF. NAM AND ECMWF SEEMED TO HAVE A
GOOD HANDLE ON LOW POSITION AND STRENGTH. THE GFS WAS A BIT TOO
FAR E WITH IT AND THE GEM JUST JUST A BIT TOO WEAK COMPARED TO
SURFACE OBS. FOR WINDS GEM AND NAM SEEMED TO HAVE SPEEDS DOWN
WHILE OTHER MODELS WERE JUST A LITTLE WEAK COMPARED TO SOME OBS.
OVERALL FEW CHANGES IN THE SHORT RANGE WITH THE MOST NOTICEABLE
CHANGES BEING STRENGTHEN THE OUTFLOW WINDS A BIT TONIGHT.

.LONG TERM...REMNANTS OF FAST MOVING CLIPPER LOW WILL CROSS FROM
THE SOUTHERN PANHANDLE INTO BRITISH COLUMBIA WEDNESDAY MORNING
WITH SOME LINGERING SHOWERS NEAR HYDER. SURFACE HIGH PRESSURE THAT
IS BUILDING OVER THE YUKON UNDER AN UPPER LEVEL TROUGH WILL TRACK
SOUTHEASTWARD BRINGING DRY CONDITIONS AND MOSTLY CLEAR SKIES TO
THE PANHANDLE. OFFSHORE FLOW BETWEEN THIS AREA OF HIGH PRESSURE
AND A LOW MOVING INTO THE AK GULF WILL BEGIN TO INCREASE LATE
WEDNESDAY NIGHT INTO THURSDAY. THIS NEXT LOW HAS POTENTIAL TO BE A
SIGNIFICANT SYSTEM PRODUCING STRONG WINDS AND SUBSTANTIAL
PRECIPITATION. AS THIS ADVANCING LOW STRENGTHENS OUTFLOW WINDS
WILL INCREASE AS THE PRESSURE GRADIENT TIGHTENS. WINDS OVER THE AK
GULF WILL ALSO INCREASE UP TO GALE FORCE AS THE FRONTAL BOUNDARIES
ASSOCIATED WITH THE LOW MOVE IN. BY THURSDAY NIGHT THE FRONT WILL
MOVE OVER THE PANHANDLE FORM SOUTH TO NORTH WITH WINDS CONTINUING
TO INCREASE. STRONGEST WINDS WILL BE ALONG EAST-WEST ORIENTED
CHANNELS, OVER COASTAL AREAS AND OUT OF INTERIOR PASSES. GUSTS UP
TO 50 MPH ARE NOT OUT OF THE QUESTION.

AFTER THE DRY WEDNESDAY AND WEDNESDAY NIGHT MORE WET WEATHER
RETURNS AND WILL REMAIN THROUGH THE WEEKEND. AS THIS INCOMING
SYSTEM INCORPORATES THE REMAINS OF TROPICAL STORM KUMMARI IT WILL
PROVIDE AMPLE MOISTURE WITH POTENTIAL FOR HEAVY RAIN STARTING
THURSDAY NIGHT INTO FRIDAY. PRECIP WILL TAPER OFF BY THE END OF
THE WEEKEND AS THE LOW FILLS AND STARTS TO EXIT THE REGION. THE
UPPER LEVEL TROUGH MOVING OVER THE PANHANDLE ON WEDNESDAY MOVES
COLD AIR MASS IN FROM THE YUKON OVER PANHANDLE WITH 850 MB TEMPS
IN THE -2 TO -6 C RANGE. CLEAR SKIES MAY PROVIDE ENOUGH INSOLATION
FOR DAY TIME TEMPS TO RISE INTO THE MID 50S. OVERNIGHT LOWS WILL
BE IN TO UPPER 20 TO LOW 30S FOR THE CENTRAL AND NORTHERN
PANHANDLE AND THE UPPER 30S TO LOW 40S FOR THE SOUTH DUE TO NOT
ONLY THE COLD UPPER LEVEL AIR BUT ALSO RADIATIONAL COOLING
RESULTING FROM CLEAR SKIES. TEMPERATURES WILL RETURN TO SEASONAL
NORMALS WITH THE ADVANCING FRONT WITH MOST PRECIP FALLING AS RAIN
BUT THERE MAY BE ENOUGH COLD AIR AT HIGHER ELEVATIONS TO PRODUCE
SNOW.

MODELS HAD GOOD CONSENSUS ON SYNOPTIC PATTERN THROUGH EARLY
THURSDAY BUT WITH LARGER MODEL SPECTRUM FOR TEMPERATURES. LEFT
GRIDS THROUGH WEDNESDAY MOSTLY AS IS DUE TO SIMILARITY TO NEW
MODEL RUNS WITH SOME LOWER TEMPS WEDNESDAY NIGHT. THE ADVANCING
SYSTEM FOR LATE IN THE WEEK BECAME MORE OF AN ISSUE. PREVIOUSLY
THE GEM HAD BEEN MODEL OF CHOICE DUE TO ITS CONSISTENCY, BUT THE
NEWEST RUN SHIFTED IN POSITION AND MORE SIGNIFICANTLY STRENGTH BY
DROPPING THE LOW CENTER TO 975 MB. THE GEM/ECMWF WERE CLOSER IN
STRENGTH WITH WEAKER GFS/NAM BUT THE GEM/GFS WERE CLOSER WITH
POSITION OF THE LOW WITH ECMWF/NAM FURTHER WEST. FOR NOW BUMPED UP
WINDS IN ANTICIPATION OF A DEEPER LOW BUT HELD OFF ON CHANGING THE
LOW POSITION UNTIL MODELS COME TO A BETTER CONSENSUS. FORECAST
CONFIDENCE IS AVERAGE FOR INTO WEDNESDAY NIGHT THEN IS WELL BELOW
AVERAGE STARTING THURSDAY.


&&

.AJK WATCHES/WARNINGS/ADVISORIES...
PUBLIC...NONE.
MARINE...GALE WARNING FOR PKZ043-052.
         SMALL CRAFT ADVISORY FOR PKZ012-013-022-033-036-041-042-051.

&&

$$

EAL/PRB

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







000
FXAK68 PAFC 301333
AFDAFC

SOUTHCENTRAL AND SOUTHWEST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE ANCHORAGE AK
533 AM AKDT TUE SEP 30 2014

ANALYSIS AND UPPER LEVELS...WATER VAPOR SATELLITE IMAGERY THIS
MORNING INDICATED THE ARCTIC TROUGH IN SOUTHERN ALASKA HAS CLOSED
OFF INTO A WEAK UPPER LEVEL CIRCULATION...WITH ASSOCIATED SURFACE
CIRCULATION MOVING QUICKLY INTO THE NORTHERN PANHANDLE. AS
EXPECTED...STRONG GAP FLOW AROUND PRINCE WILLIAM SOUND PEAKED
EARLIER THIS MORNING...WITH OBSERVATIONS SHOWING A STEADY DECLINE
IN THOSE WINDS AS THE TROUGH PUSHES OFF FURTHER TO THE EAST.
MEANWHILE...HIGH PRESSURE CONTINUES TO SLOWLY BUILD INTO FROM THE
WEST.

FURTHER WEST...AN UPPER RIDGE PERSISTS OVER THE NORTHERN BERING
SEA...WITH A VERTICALLY STACKED LOW NEARLY STATIONARY WELL SOUTH
OF THE ALEUTIANS. LIGHT RAIN AND GUSTY WINDS ON THE FRINGES OF
THIS SYSTEM ARE BEING OBSERVED ACROSS THE EASTERN HALF OF THE
ALEUTIAN CHAIN.

&&

MODEL DISCUSSION...THE MODELS REMAIN IN GOOD SYNOPTIC AGREEMENT AT
BOTH THE SURFACE AND UPPER LEVELS THROUGHOUT MUCH OF THE SHORT-
TERM (84 HOUR) FORECAST PERIOD. HOWEVER...DIFFERENCES DO ARISE
EARLY THURSDAY MORNING SOUTH OF THE GULF WITH THE HANDLING OF THE
NEXT LOW COMPLEX. THE MODELS GENERALLY SHOW THE REMNANTS OF AN OLD
TROPICAL SYSTEM (KAMMURI) WITH AMPLE MOISTURE BECOMING ABSORBED BY
THE LOW CURRENTLY SOUTH OF THE CENTRAL ALEUTIANS. AS EXPECTED THE
MODELS CONTINUE TO STRUGGLE WITH THIS COMPLEX SYSTEM AS IT TRACKS
SLOWLY NORTHEASTWARD TOWARD THE SOUTHERN GULF. THE FORECAST
CHALLENGE WITH THIS SYSTEM WILL BE IF AND WHERE A TRIPLE POINT
CIRCULATION FORMS ON THURSDAY...AND HOW DEEP/STRONG IT WILL GET.
WITH THIS BEING AT THE END OF THE SHORT TERM AND HAVING SUCH MODEL
SPREAD AT THAT TIME FRAME...FORECAST CONFIDENCE REMAINS LOW
REGARDING THE KEY DETAILS OF THIS EVOLUTION. THE GEM GLOBAL WAS
THE PREFERRED SOLUTION OVERALL WITH THIS SYSTEM AND IS FAIRLY
CLOSE TO THE GFS ENSEMBLE MEAN AND WPC SOLUTIONS.

PRIOR TO 60 HOURS...THE NAM WAS MAINLY UTILIZED OVER THE EAST
DOMAIN TO CONTINUE CAPTURING THE ONGOING GAP WINDS. THE ECMWF
SOLUTION WAS PREFERRED OVER THE WESTERN DOMAIN FOR THE MORNING
PACKAGE FOR SUPERIOR RUN-TO-RUN CONSISTENCY.

&&

.SHORT TERM FORECAST...
SOUTHCENTRAL ALASKA...SUBSIDENCE BEHIND THE DEPARTING UPPER LEVEL
WAVE COUPLED WITH TIGHT PRESSURE GRADIENTS LED TO GUSTY
CONDITIONS AND STRONG GAP FLOW OVER PRINCE WILLIAM SOUND AND PARTS
OF SOUTHCENTRAL OVERNIGHT. WINDS HAVE NOW PEAKED AT MANY
LOCATIONS...AND WILL GRADUALLY DIMINISH THROUGHOUT THE DAY TODAY
AS THE UPPER LEVEL TROUGH CONTINUES TO MOVE AWAY. PRECIPITATION
ASSOCIATED WITH THIS FEATURE IS LIMITED TO THE FAR EASTERN COPPER
RIVER BASIN...AND EVEN THIS WILL RAPIDLY DIMINISH BY LATER THIS
MORNING AS COLDER AND DRIER AIR MOVES IN FROM THE WEST.

SOUTHWEST ALASKA...CONDITIONS WILL BE RELATIVELY DRY ACROSS
THE SOUTHWEST MAINLAND OVER THE NEXT COUPLE OF DAYS AS HIGH
PRESSURE REMAINS OVER THE AREA. AN ONSHORE COMPONENT OF THE WINDS
ACROSS THE KUSKOKWIM DELTA WILL KEEP THE POTENTIAL FOR A LITTLE
FOG AROUND THE AREA THROUGH THIS EVENING. HOWEVER...INCREASINGLY
OFFSHORE FLOW BY LATE THIS AFTERNOON WILL LIKELY HAMPER ANY FOG
FORMATION/ADVECTION OVER THE MAJORITY OF THE AREA OVER THE NEXT
DAY OR SO. MEANWHILE...BRISK (BUT MOSTLY DRY) EASTERLY FLOW
ASSOCIATED WITH A LOW COMPLEX OVER THE NORTH PACIFIC WILL CONTINUE
ACROSS THE AK PEN THROUGH WED.

BERING SEA/ALEUTIANS...RAIN AND WIND WILL CONTINUE TO JUST BARELY
BRUSH THE ALEUTIAN ISLANDS AS THE LOW CONTINUES TO SLOWLY TRACK
TO THE EAST. OTHERWISE HIGH PRESSURE WILL BUILD OVER THE CENTRAL
BERING SEA AND CONTINUE TO STRENGTHEN THROUGH MID
WEEK...CONTINUING THE SPLIT-FLOW BLOCKING PATTERN AND PROVIDING
VERY QUIET CONDITIONS FOR MOST OF THE REGION.

&&

.LONG TERM FORECAST (FRI OCT 3 - MON OCT 6)...

ON FRIDAY...A HIGHLY AMPLIFIED PATTERN WILL BE DEVELOPING ACROSS
THE REGION...WITH A BLOCKING RIDGE ACROSS THE CENTRAL BERING
EXTENDING INTO SIBERIA...AND A LARGE TROUGH ACROSS THE MAINLAND.
ARCTIC AIR WILL ACCOMPANY THE TROUGH...WITH STEADILY DROPPING
TEMPERATURES HEADING INTO THE WEEKEND. THE PATTERN WILL GENERALLY
BE DRY...BUT THERE IS THE THREAT FOR SNOW AND SNOW SHOWERS ACROSS
MOST OF SOUTHCENTRAL BY THE WEEKEND...ESPECIALLY ACROSS THE COPPER
BASIN. THERE REMAINS UNCERTAINTY WITH A LOW MOVING THROUGH THE
EASTERN GULF OF ALASKA...SO A CONSERVATIVE MIDDLE GROUND APPROACH
WAS TAKEN WITH THE PRECIPITATION FORECAST. BY MONDAY...UNCERTAINTY
IN THE PATTERN GROWS IN MAGNITUDE QUICKLY AS THE TRACK OF
NORTHWEST PACIFIC CYCLONES (POSSIBLY INCLUDING RECURVING REMNANTS
OF PACIFIC TROPICAL CYCLONES) MOVING INTO THE BERING BECOMES
HIGHLY ERRATIC...THUS RESULTING IN SYNOPTIC SCALE DISAGREEMENT
AMONG THE VARIOUS GLOBAL NUMERICAL MODELS. WITH THAT SAID...THE
COLDEST TEMPS OF THE FALL CAN BE EXPECTED BY THIS WEEKEND.


&&


.AFC WATCHES/WARNINGS/ADVISORIES...
PUBLIC...NONE.
MARINE...GALE WARNING...119 127 150 155 172 174.
FIRE WEATHER...NONE.

&&

$$

TP SEP 14



000
FXAK68 PAFC 301333
AFDAFC

SOUTHCENTRAL AND SOUTHWEST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE ANCHORAGE AK
533 AM AKDT TUE SEP 30 2014

ANALYSIS AND UPPER LEVELS...WATER VAPOR SATELLITE IMAGERY THIS
MORNING INDICATED THE ARCTIC TROUGH IN SOUTHERN ALASKA HAS CLOSED
OFF INTO A WEAK UPPER LEVEL CIRCULATION...WITH ASSOCIATED SURFACE
CIRCULATION MOVING QUICKLY INTO THE NORTHERN PANHANDLE. AS
EXPECTED...STRONG GAP FLOW AROUND PRINCE WILLIAM SOUND PEAKED
EARLIER THIS MORNING...WITH OBSERVATIONS SHOWING A STEADY DECLINE
IN THOSE WINDS AS THE TROUGH PUSHES OFF FURTHER TO THE EAST.
MEANWHILE...HIGH PRESSURE CONTINUES TO SLOWLY BUILD INTO FROM THE
WEST.

FURTHER WEST...AN UPPER RIDGE PERSISTS OVER THE NORTHERN BERING
SEA...WITH A VERTICALLY STACKED LOW NEARLY STATIONARY WELL SOUTH
OF THE ALEUTIANS. LIGHT RAIN AND GUSTY WINDS ON THE FRINGES OF
THIS SYSTEM ARE BEING OBSERVED ACROSS THE EASTERN HALF OF THE
ALEUTIAN CHAIN.

&&

MODEL DISCUSSION...THE MODELS REMAIN IN GOOD SYNOPTIC AGREEMENT AT
BOTH THE SURFACE AND UPPER LEVELS THROUGHOUT MUCH OF THE SHORT-
TERM (84 HOUR) FORECAST PERIOD. HOWEVER...DIFFERENCES DO ARISE
EARLY THURSDAY MORNING SOUTH OF THE GULF WITH THE HANDLING OF THE
NEXT LOW COMPLEX. THE MODELS GENERALLY SHOW THE REMNANTS OF AN OLD
TROPICAL SYSTEM (KAMMURI) WITH AMPLE MOISTURE BECOMING ABSORBED BY
THE LOW CURRENTLY SOUTH OF THE CENTRAL ALEUTIANS. AS EXPECTED THE
MODELS CONTINUE TO STRUGGLE WITH THIS COMPLEX SYSTEM AS IT TRACKS
SLOWLY NORTHEASTWARD TOWARD THE SOUTHERN GULF. THE FORECAST
CHALLENGE WITH THIS SYSTEM WILL BE IF AND WHERE A TRIPLE POINT
CIRCULATION FORMS ON THURSDAY...AND HOW DEEP/STRONG IT WILL GET.
WITH THIS BEING AT THE END OF THE SHORT TERM AND HAVING SUCH MODEL
SPREAD AT THAT TIME FRAME...FORECAST CONFIDENCE REMAINS LOW
REGARDING THE KEY DETAILS OF THIS EVOLUTION. THE GEM GLOBAL WAS
THE PREFERRED SOLUTION OVERALL WITH THIS SYSTEM AND IS FAIRLY
CLOSE TO THE GFS ENSEMBLE MEAN AND WPC SOLUTIONS.

PRIOR TO 60 HOURS...THE NAM WAS MAINLY UTILIZED OVER THE EAST
DOMAIN TO CONTINUE CAPTURING THE ONGOING GAP WINDS. THE ECMWF
SOLUTION WAS PREFERRED OVER THE WESTERN DOMAIN FOR THE MORNING
PACKAGE FOR SUPERIOR RUN-TO-RUN CONSISTENCY.

&&

.SHORT TERM FORECAST...
SOUTHCENTRAL ALASKA...SUBSIDENCE BEHIND THE DEPARTING UPPER LEVEL
WAVE COUPLED WITH TIGHT PRESSURE GRADIENTS LED TO GUSTY
CONDITIONS AND STRONG GAP FLOW OVER PRINCE WILLIAM SOUND AND PARTS
OF SOUTHCENTRAL OVERNIGHT. WINDS HAVE NOW PEAKED AT MANY
LOCATIONS...AND WILL GRADUALLY DIMINISH THROUGHOUT THE DAY TODAY
AS THE UPPER LEVEL TROUGH CONTINUES TO MOVE AWAY. PRECIPITATION
ASSOCIATED WITH THIS FEATURE IS LIMITED TO THE FAR EASTERN COPPER
RIVER BASIN...AND EVEN THIS WILL RAPIDLY DIMINISH BY LATER THIS
MORNING AS COLDER AND DRIER AIR MOVES IN FROM THE WEST.

SOUTHWEST ALASKA...CONDITIONS WILL BE RELATIVELY DRY ACROSS
THE SOUTHWEST MAINLAND OVER THE NEXT COUPLE OF DAYS AS HIGH
PRESSURE REMAINS OVER THE AREA. AN ONSHORE COMPONENT OF THE WINDS
ACROSS THE KUSKOKWIM DELTA WILL KEEP THE POTENTIAL FOR A LITTLE
FOG AROUND THE AREA THROUGH THIS EVENING. HOWEVER...INCREASINGLY
OFFSHORE FLOW BY LATE THIS AFTERNOON WILL LIKELY HAMPER ANY FOG
FORMATION/ADVECTION OVER THE MAJORITY OF THE AREA OVER THE NEXT
DAY OR SO. MEANWHILE...BRISK (BUT MOSTLY DRY) EASTERLY FLOW
ASSOCIATED WITH A LOW COMPLEX OVER THE NORTH PACIFIC WILL CONTINUE
ACROSS THE AK PEN THROUGH WED.

BERING SEA/ALEUTIANS...RAIN AND WIND WILL CONTINUE TO JUST BARELY
BRUSH THE ALEUTIAN ISLANDS AS THE LOW CONTINUES TO SLOWLY TRACK
TO THE EAST. OTHERWISE HIGH PRESSURE WILL BUILD OVER THE CENTRAL
BERING SEA AND CONTINUE TO STRENGTHEN THROUGH MID
WEEK...CONTINUING THE SPLIT-FLOW BLOCKING PATTERN AND PROVIDING
VERY QUIET CONDITIONS FOR MOST OF THE REGION.

&&

.LONG TERM FORECAST (FRI OCT 3 - MON OCT 6)...

ON FRIDAY...A HIGHLY AMPLIFIED PATTERN WILL BE DEVELOPING ACROSS
THE REGION...WITH A BLOCKING RIDGE ACROSS THE CENTRAL BERING
EXTENDING INTO SIBERIA...AND A LARGE TROUGH ACROSS THE MAINLAND.
ARCTIC AIR WILL ACCOMPANY THE TROUGH...WITH STEADILY DROPPING
TEMPERATURES HEADING INTO THE WEEKEND. THE PATTERN WILL GENERALLY
BE DRY...BUT THERE IS THE THREAT FOR SNOW AND SNOW SHOWERS ACROSS
MOST OF SOUTHCENTRAL BY THE WEEKEND...ESPECIALLY ACROSS THE COPPER
BASIN. THERE REMAINS UNCERTAINTY WITH A LOW MOVING THROUGH THE
EASTERN GULF OF ALASKA...SO A CONSERVATIVE MIDDLE GROUND APPROACH
WAS TAKEN WITH THE PRECIPITATION FORECAST. BY MONDAY...UNCERTAINTY
IN THE PATTERN GROWS IN MAGNITUDE QUICKLY AS THE TRACK OF
NORTHWEST PACIFIC CYCLONES (POSSIBLY INCLUDING RECURVING REMNANTS
OF PACIFIC TROPICAL CYCLONES) MOVING INTO THE BERING BECOMES
HIGHLY ERRATIC...THUS RESULTING IN SYNOPTIC SCALE DISAGREEMENT
AMONG THE VARIOUS GLOBAL NUMERICAL MODELS. WITH THAT SAID...THE
COLDEST TEMPS OF THE FALL CAN BE EXPECTED BY THIS WEEKEND.


&&


.AFC WATCHES/WARNINGS/ADVISORIES...
PUBLIC...NONE.
MARINE...GALE WARNING...119 127 150 155 172 174.
FIRE WEATHER...NONE.

&&

$$

TP SEP 14




000
FXAK69 PAFG 301300
AFDAFG

NORTHERN ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE FAIRBANKS AK
500 AM AKDT TUE SEP 30 2014

.DISCUSSION...
ALOFT...BROAD TROUGH FROM THE ARCTIC TO THE GULF OF ALASKA WILL
MOVE OFF TO THE EAST BUT THEN REFORM BY THU AS ANOTHER TROUGH
OVER THE RUSSIAN ARCTIC DIGS SOUTH OVER WESTERN ALASKA. THIS
TROUGH WILL CAUSE THE RIDGE OVERING THE BERING SEA TO WEAKEN SOME
ON THU AND SHIFT WEST. NORTHWEST FLOW OVER THE WEST HALF OF THE
STATE WITH A FEW SHORT WAVE TROUGHS EMBEDDED WILL SPREAD EAST
TODAY AND THEN BEGIN WEAKENING ACROSS THE FORECAST AREA ON WED.

SURFACE...1000 MB LOW NEAR YAKUTAT WILL WEAKEN AND MOVE SOUTHEAST
TODAY. 1004 MB LOW 120 MILES NORTHEAST OF BARROW WILL WEAKEN AS IT
MOVES TO NEAR BARTER ISLAND 4PM TODAY AND THEN DISSIPATES. A
SECOND LOW PRESSURE CENTER OF 1008 MB ALONG THE RUSSIAN ARCTIC
COAST WILL MOVE TO NEAR BARROW WED AM AT 1012 MB...THEN TO 100
MILES NORTHEAST OF BARTER ISLAND 4AM THU. 1028 MB HIGH CENTER NEAR
SAINT MATTHEW ISLAND WILL DRIFT NORTH THROUGH WED THEN MOVE TO THE
CHUKOTSK PENINSULA THU.

MODELS...AT THE SURFACE THE MODELS AGREE WELL IN POSITION OF THE
LOWS MOVING ALONG IN THE ARCTIC...WHERE THERE IS VARIANCE IS IN
THE DEPTH OF THE LOW...THOUGH IT IS WEAK ENOUGH TO NOT MAKE MUCH
OF A DIFFERENCE. IN THE MEDIUM TERM MODELS AGREE FAIRLY CLOSE
THROUGH MON AND THEN BEGIN TO DIVERGE.

NORTH SLOPE...WINDS OVER THE WESTERN ARCTIC COAST ARE DIMINISHING
THIS MORNING...AND WHILE WINDS WILL INCREASE ALONG THE NORHTERN
ARCTIC COAST TODAY AS THE LOW MOVES OFF TO THE EAST...WINDS SHOULD
NOT BE HIGH ENOUGH TO WARRANT PROLONGED SURF CONCERNS. SO HAVE
REMOVED THE HIGH SURF ADVISORIES. THE NEXT LOW MOVING ACROSS ON
WED AND THU MAY BRING SURF UP AGAIN THOUGH THE FEATURE IS MOVING
FAST ENOUGH TO KEEP THE POTENTIAL FOR PROBLEMS LOW. WITH THE
CURRENT LOW AND THE NEXT LOW MOVING ALONG NORTH OF THE
COAST...EXPECT PERIODS OF SNOW THROUGH THE REMAINDER OF THE WEEK
WITH AMOUNTS ENHANCED ALONG THE NORTHEASTERN SLOPES OF THE BROOKS
RANGE.

WESTERN ALASKA...WINDS OVER THE NORTHWEST COASTLINE ARE
DIMINISHING THIS MORNING AND THE HIGH SURF ADVISORIES HAVE BEEN
REMOVED. SPOTTY RAIN AND SNOW SHOWERS EXPECTED NORTH OF THE
SEWARD PENINSULA TODAY. WITH INCOMING TROUGH MOVING SOUTH OVER THE
AREA THU IT WILL BRING MORE RAIN AND SNOW WED OVER THE NORTHWEST
ZONES...MOVING TO THE SEWARD PENINSULA...MIDDLE YUKON VALLEY...AND
NULATO HILLS ON THU.

CENTRAL AND EASTERN INTERIOR...A SHORT WAVE TROUGH FROM ATIGUN
PASS TO FAIRBANKS THIS MORNING WILL MOVE TO THE CANADA BORDER BY
4PM TODAY. THERE WILL BE SCATTERED SNOW AND RAIN SHOWERS WITH THIS
FEATURE AND EXPECT AMOUNTS TO BE LIGHT...THOUGH AN INCH OR TWO OF
SNOW COULD OCCUR OVER THE HIGHER ELEVATIONS OF THE MIDDLE TANANA
VALLEY AND FORTYMILE COUNTRY. SOME RAIN AND SNOW THIS MORNING
OVER THE FAR UPPER TANANA VALLEY AND FAR EASTERN ALASKA RANGE DUE
TO THE LOW NEAR YAKUTAT. ON THU THE DIGGING TROUGH OVER WESTERN
ALASKA WILL PRODUCE LIGHT SOUTHWEST FLOW OVER THE CENTRAL INTERIOR
WHICH WILL HELP SPREAD ANOTHER ROUND OF RAIN AND SNOW SHOWERS
ACROSS THE AREA...BUT NORTH OF FAIRBANKS.

COASTAL HAZARD POTENTIAL DAYS 3 AND 4...NONE

&&

.HYDROLOGY...NONE.

&&

.AFG WATCHES/WARNINGS/ADVISORIES...
SMALL CRAFT ADVISORY FOR PKZ215-PKZ220-PKZ230-PKZ235.
&&

$$

JL SEP 14




000
FXAK67 PAJK 300043 CCA
AFDAJK

SOUTHEAST ALASKA FORECAST DISCUSSION...CORRECTED
NATIONAL WEATHER SERVICE JUNEAU AK
442 PM AKDT MON SEP 29 2014

SHORT TERM...A WEAKENING VERTICALLY STACKED LOW OVER THE
SOUTHEAST GULF OF ALASKA WILL CONTINUE MOVING ACROSS NORTHERN HAIDA
GWAII THIS EVENING AND WILL DISSIPATE OVER THE BRITISH COLUMBIA
COAST BY TUESDAY MORNING. THE SHOWERS HAVE WEAKENED TO THE POINT
WHERE THUNDERSTORMS ARE UNLIKELY THROUGH THE EVENING OVER THE
SOUTHERN PANHANDLE.

SHOWER ACTIVITY OVER THE NORTHERN AND CENTRAL INNER CHANNELS WILL
TAPER OFF TO ISOLATED ACTIVITY LATER THIS EVENING. ACTIVITY OVER
THE SOUTHERN PANHANDLE WILL BE SLOWER TO TAPER OFF OVERNIGHT.

MEANWHILE AN UPPER LEVEL TROUGH WITH A VIGOROUS SHORT WAVE MOVING
FROM THE SOUTH CENTRAL PORTION OF THE STATE INTO THE NORTHERN GULF
IS SPINNING UP A SURFACE LOW NEAR CAPE SUCKLING. THIS LOW IS
EXPECTED TO MOVE SOUTHEAST ALONG THE COASTLINE TO NEAR CAPE SPENCER
BY TUESDAY AFTERNOON AND THEN BEGIN TO WEAKEN. THE TROUGH IS
USHERING IN A BURST OF COLDER AIR ALOFT AND THIS WILL
START TO INFILTRATE THE NORTHEAST GULF COAST...ALSO ON TUESDAY. THE
AIR ALOFT WILL ADD TO THE INSTABILITY ALLOWING FOR SOME SIGNIFICANT
SHOWER ACTIVITY. THUNDERSTORMS ARE POSSIBLE, BUT CONFIDENCE NOT
HIGH ENOUGH TO INCLUDE THEM IN THE FORECAST AS OF YET.

WINDS ON SOUTH AND SOUTHWEST SIDE OF LOW DEVELOPING TONIGHT OVER
THE NORTHERN GULF WILL INCREASE TO GALE FORCE (35 KT) FOR THE
NORTHERN OFFSHORE AND MARINE ZONE 52. ELSEWHERE...LOOK FOR WINDS TO
PICK UP TO SMALL CRAFT INTENSITY BY TUESDAY AFTERNOON.

LONG TERM...UPPER IMPULSE OBSERVED IN WV IMAGERY OVER THE NRN
GULF THIS AFTERNOON IS FORECAST TO MOVE ACROSS THE NRN PANHANDLE
AND INTO NRN B.C. BY TUE NIGHT. COLD AIR ALOFT /NEAR -30C AT 500
MB/ WILL SUPPORT A CONVECTIVE/SHOWERY REGIME WITH THE PASSING
TROUGH. HOWEVER...ANY THUNDERSTORM POTENTIAL SHOULD BE LOCATED E
OF THE CWA BY THE START OF THE LONG TERM PERIOD AS FORCING FOR
ASCENT ASSOCIATED WITH AN UPPER VORT LOBE EXITS THE REGION. A MUCH
COLDER LOW-LEVEL AIRMASS /-2 TO -8 AT 850 MB/ IS FORECAST TO
SPREAD SE ACROSS THE PANHANDLE AFTER THE PASSAGE OF THE UPPER
TROUGH. WITH SKIES CLEARING QUICKLY OVER YAKUTAT...LOWS ARE
FORECAST TO FALL TO NEAR 30F TUE NIGHT AS WELL AS WED NIGHT. IN
ADDITION...DRY AIR AND CLEAR SKIES SPREAD ESE ACROSS THE
REMAINDER OF THE CWA WED NIGHT...WHICH WILL FAVOR LOWS IN THE MID
30S TO AROUND 40 OVER MUCH OF THE AREA.

SURFACE PRESSURE PATTERN WILL BECOME CONDUCIVE FOR INCREASING
OUTFLOW WINDS THU THROUGH FRI AS HIGH PRESSURE BECOMES POSITIONED
OVER NWRN CANADA AND A LOW ENTERS THE SRN GULF. SMALL CRAFT NELY
WINDS WILL BE PROBABLE OVER CROSS SOUND...FREDERICK SOUND...AND
SUMNER STRAIT...WITH NLY WINDS UP TO 30 KT EXPECTED IN NRN AND SRN
LYNN CANAL. THOUGH ONLY COARSE DETERMINISTIC MODEL GUIDANCE IS
CURRENTLY AVAILABLE...12 KM NAM SHOWS 20-30 KT OF CROSS BARRIER
FLOW OCCURRING INVOF GASTINEAU CHANNEL. THIS FLOW COMBINED WITH A
ZONE OF FLOW REVERSAL ALOFT SIGNALS THE POTENTIAL FOR GUSTY WINDS
IN DOWNTOWN JUNEAU AND S DOUGLAS.

A FRONTAL BOUNDARY MOVES NNE INTO THE SRN PANHANDLE THU
NIGHT...WHICH WILL USHER IN STRENGTHENING SLY WINDS AND ANOTHER
ROUND OF MODERATE RAINFALL. THE ECMWF SHOWS A STRONGER SURFACE
CYCLONE OVER THE GULF COMPARED TO THE GFS/GEM. SMOOTHED OUT THESE
DIFFERENCES FOR THE TIME BEING WHILE TRANSITIONING TO THE WPC FRI-
SAT. IN GENERAL...THIS RESULTED IN ONLY MINOR CHANGES FROM
PREVIOUS LONG TERM FORECAST. CONFIDENCE IS AT OR ABOVE AVERAGE FOR
COOLING TREND GOING INTO MID WEEK...AS WELL AS THE ONSET OF THE
NEXT PRECIPITATION EVENT LATER IN THE WEEK.

&&

.AJK WATCHES/WARNINGS/ADVISORIES...
PUBLIC...NONE.
MARINE...GALE WARNING FOR PKZ052.
         SMALL CRAFT ADVISORY FOR PKZ033-036-041>043-051.

&&

$$

BEZENEK/GARNER

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




000
FXAK67 PAJK 300043 CCA
AFDAJK

SOUTHEAST ALASKA FORECAST DISCUSSION...CORRECTED
NATIONAL WEATHER SERVICE JUNEAU AK
442 PM AKDT MON SEP 29 2014

SHORT TERM...A WEAKENING VERTICALLY STACKED LOW OVER THE
SOUTHEAST GULF OF ALASKA WILL CONTINUE MOVING ACROSS NORTHERN HAIDA
GWAII THIS EVENING AND WILL DISSIPATE OVER THE BRITISH COLUMBIA
COAST BY TUESDAY MORNING. THE SHOWERS HAVE WEAKENED TO THE POINT
WHERE THUNDERSTORMS ARE UNLIKELY THROUGH THE EVENING OVER THE
SOUTHERN PANHANDLE.

SHOWER ACTIVITY OVER THE NORTHERN AND CENTRAL INNER CHANNELS WILL
TAPER OFF TO ISOLATED ACTIVITY LATER THIS EVENING. ACTIVITY OVER
THE SOUTHERN PANHANDLE WILL BE SLOWER TO TAPER OFF OVERNIGHT.

MEANWHILE AN UPPER LEVEL TROUGH WITH A VIGOROUS SHORT WAVE MOVING
FROM THE SOUTH CENTRAL PORTION OF THE STATE INTO THE NORTHERN GULF
IS SPINNING UP A SURFACE LOW NEAR CAPE SUCKLING. THIS LOW IS
EXPECTED TO MOVE SOUTHEAST ALONG THE COASTLINE TO NEAR CAPE SPENCER
BY TUESDAY AFTERNOON AND THEN BEGIN TO WEAKEN. THE TROUGH IS
USHERING IN A BURST OF COLDER AIR ALOFT AND THIS WILL
START TO INFILTRATE THE NORTHEAST GULF COAST...ALSO ON TUESDAY. THE
AIR ALOFT WILL ADD TO THE INSTABILITY ALLOWING FOR SOME SIGNIFICANT
SHOWER ACTIVITY. THUNDERSTORMS ARE POSSIBLE, BUT CONFIDENCE NOT
HIGH ENOUGH TO INCLUDE THEM IN THE FORECAST AS OF YET.

WINDS ON SOUTH AND SOUTHWEST SIDE OF LOW DEVELOPING TONIGHT OVER
THE NORTHERN GULF WILL INCREASE TO GALE FORCE (35 KT) FOR THE
NORTHERN OFFSHORE AND MARINE ZONE 52. ELSEWHERE...LOOK FOR WINDS TO
PICK UP TO SMALL CRAFT INTENSITY BY TUESDAY AFTERNOON.

LONG TERM...UPPER IMPULSE OBSERVED IN WV IMAGERY OVER THE NRN
GULF THIS AFTERNOON IS FORECAST TO MOVE ACROSS THE NRN PANHANDLE
AND INTO NRN B.C. BY TUE NIGHT. COLD AIR ALOFT /NEAR -30C AT 500
MB/ WILL SUPPORT A CONVECTIVE/SHOWERY REGIME WITH THE PASSING
TROUGH. HOWEVER...ANY THUNDERSTORM POTENTIAL SHOULD BE LOCATED E
OF THE CWA BY THE START OF THE LONG TERM PERIOD AS FORCING FOR
ASCENT ASSOCIATED WITH AN UPPER VORT LOBE EXITS THE REGION. A MUCH
COLDER LOW-LEVEL AIRMASS /-2 TO -8 AT 850 MB/ IS FORECAST TO
SPREAD SE ACROSS THE PANHANDLE AFTER THE PASSAGE OF THE UPPER
TROUGH. WITH SKIES CLEARING QUICKLY OVER YAKUTAT...LOWS ARE
FORECAST TO FALL TO NEAR 30F TUE NIGHT AS WELL AS WED NIGHT. IN
ADDITION...DRY AIR AND CLEAR SKIES SPREAD ESE ACROSS THE
REMAINDER OF THE CWA WED NIGHT...WHICH WILL FAVOR LOWS IN THE MID
30S TO AROUND 40 OVER MUCH OF THE AREA.

SURFACE PRESSURE PATTERN WILL BECOME CONDUCIVE FOR INCREASING
OUTFLOW WINDS THU THROUGH FRI AS HIGH PRESSURE BECOMES POSITIONED
OVER NWRN CANADA AND A LOW ENTERS THE SRN GULF. SMALL CRAFT NELY
WINDS WILL BE PROBABLE OVER CROSS SOUND...FREDERICK SOUND...AND
SUMNER STRAIT...WITH NLY WINDS UP TO 30 KT EXPECTED IN NRN AND SRN
LYNN CANAL. THOUGH ONLY COARSE DETERMINISTIC MODEL GUIDANCE IS
CURRENTLY AVAILABLE...12 KM NAM SHOWS 20-30 KT OF CROSS BARRIER
FLOW OCCURRING INVOF GASTINEAU CHANNEL. THIS FLOW COMBINED WITH A
ZONE OF FLOW REVERSAL ALOFT SIGNALS THE POTENTIAL FOR GUSTY WINDS
IN DOWNTOWN JUNEAU AND S DOUGLAS.

A FRONTAL BOUNDARY MOVES NNE INTO THE SRN PANHANDLE THU
NIGHT...WHICH WILL USHER IN STRENGTHENING SLY WINDS AND ANOTHER
ROUND OF MODERATE RAINFALL. THE ECMWF SHOWS A STRONGER SURFACE
CYCLONE OVER THE GULF COMPARED TO THE GFS/GEM. SMOOTHED OUT THESE
DIFFERENCES FOR THE TIME BEING WHILE TRANSITIONING TO THE WPC FRI-
SAT. IN GENERAL...THIS RESULTED IN ONLY MINOR CHANGES FROM
PREVIOUS LONG TERM FORECAST. CONFIDENCE IS AT OR ABOVE AVERAGE FOR
COOLING TREND GOING INTO MID WEEK...AS WELL AS THE ONSET OF THE
NEXT PRECIPITATION EVENT LATER IN THE WEEK.

&&

.AJK WATCHES/WARNINGS/ADVISORIES...
PUBLIC...NONE.
MARINE...GALE WARNING FOR PKZ052.
         SMALL CRAFT ADVISORY FOR PKZ033-036-041>043-051.

&&

$$

BEZENEK/GARNER

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



000
FXAK67 PAJK 292338
AFDAJK

SOUTHEAST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE JUNEAU AK
338 PM AKDT MON SEP 29 2014

.SHORT TERM...THE WEAKENING VERTICALLY STACKED LOW OVER THE
SOUTHEAST GULF OF ALASKA WILL CONTINUE MOVING ACROSS NORTHERN HAIDA
GWAII THIS EVENING AND WILL DISSIPATE OVER THE BRITISH COLUMBIA
COAST BY TUESDAY MORNING. THE SHOWERS HAVE WEAKENED TO THE LEVEL
WHERE DO NOT THINK THUNDER WILL BE AROUND THROUGH THE EVENING OVER
THE SOUTHERN PANHANDLE.

OVER THE NORTHERN INNER CHANNELS REGION THIS EVENING AN TO THE
CENTRAL SHOWER ACTIVITY TAPERING OFF TO ISOLATED SHOWERS OR
EVEN JUST SOME SPRINKLES. THINK THAT SOUTHERN PANHANDLE WILL
SLOWLY TAPER OF OVERNIGHT.

MEANWHILE AN UPPER LEVEL TROUGH WITH A VIGOROUS SHORT WAVE MOVING
FROM THE SOUTH CENTRAL PORTION OF THE STATE INTO THE NORTHERN GULF
SPINNING UP A SURFACE LOW NEAR CAPE SUCKLING. THIS LOW IS EXPECTED
TO MOVE SOUTHEAST ALONG THE COASTLINE TO NEAR CAPE SPENSER BY
TUESDAY AFTERNOON. THE LOW SHOULD START TO WEAKEN ON TUESDAY. THE
TROUGH IS USHERING IN A BURST OF COLDER AIR ALOFT AND THIS WILL
START TO INFILTRATE THE NORTHEAST GULF COAST TUESDAY. THE AIR
ALOFT WILL ADD TO THE INSTABILITY ALLOWING FOR SOME SIGNIFICANT
SHOWERS POSSIBLY EVEN SOME THUNDER BUT WILL NOT PUT IN FORECAST.

WINDS ON SOUTH AND SOUTHWEST SIDE OF THIS SPIN UP LOW WILL
INCREASE TO GALE FORCE (35 KT) FOR THE NORTHERN OFFSHORE AND
MARINE ZONE 52...OTHERWISE LOOK FOR WINDS TO PICK UP TO SMALL CRAFT
BY TUESDAY AFTERNOON.

.LONG TERM...UPPER IMPULSE OBSERVED IN WV IMAGERY OVER THE NRN
GULF THIS AFTERNOON IS FORECAST TO MOVE ACROSS THE NRN PANHANDLE
AND INTO NRN B.C. BY TUE NIGHT. COLD AIR ALOFT /NEAR -30C AT 500
MB/ WILL SUPPORT A CONVECTIVE/SHOWERY REGIME WITH THE PASSING
TROUGH. HOWEVER...ANY THUNDERSTORM POTENTIAL SHOULD BE LOCATED E
OF THE CWA BY THE START OF THE LONG TERM PERIOD AS FORCING FOR
ASCENT ASSOCIATED WITH AN UPPER VORT LOBE EXITS THE REGION. A MUCH
COLDER LOW-LEVEL AIRMASS /-2 TO -8 AT 850 MB/ IS FORECAST TO
SPREAD SE ACROSS THE PANHANDLE AFTER THE PASSAGE OF THE UPPER
TROUGH. WITH SKIES CLEARING QUICKLY OVER YAKUTAT...LOWS ARE
FORECAST TO FALL TO NEAR 30F TUE NIGHT AS WELL AS WED NIGHT. IN
ADDITION...DRY AIR AND CLEAR SKIES SPREAD ESE ACROSS THE
REMAINDER OF THE CWA WED NIGHT...WHICH WILL FAVOR LOWS IN THE MID
30S TO AROUND 40 OVER MUCH OF THE AREA.

SURFACE PRESSURE PATTERN WILL BECOME CONDUCIVE FOR INCREASING OUTFLOW
WINDS THU THROUGH FRI AS HIGH PRESSURE BECOMES POSITIONED OVER
NWRN CANADA AND A LOW ENTERS THE SRN GULF. SMALL CRAFT NELY WINDS
WILL BE PROBABLE OVER CROSS SOUND...FREDERICK SOUND...AND SUMNER
STRAIT...WITH NLY WINDS UP TO 30 KT EXPECTED IN NRN AND SRN LYNN
CANAL. THOUGH ONLY COARSE DETERMINISTIC MODEL GUIDANCE IS
CURRENTLY AVAILABLE...12 KM NAM SHOWS 20-30 KT OF CROSS BARRIER
FLOW OCCURRING INVOF GASTINEAU CHANNEL. THIS FLOW COMBINED WITH A
ZONE OF FLOW REVERSAL ALOFT SIGNALS THE POTENTIAL FOR GUSTY WINDS
IN DOWNTOWN JUNEAU AND S DOUGLAS.

A FRONTAL BOUNDARY MOVES NNE INTO THE SRN PANHANDLE THU
NIGHT...WHICH WILL USHER IN STRENGTHENING SLY WINDS AND ANOTHER
ROUND OF MODERATE RAINFALL. THE ECMWF SHOWS A STRONGER SURFACE
CYCLONE OVER THE GULF COMPARED TO THE GFS/GEM. SMOOTHED OUT THESE
DIFFERENCES FOR THE TIME BEING WHILE TRANSITIONING TO THE WPC FRI-
SAT. IN GENERAL...THIS RESULTED IN ONLY MINOR CHANGES FROM
PREVIOUS LONG TERM FORECAST. CONFIDENCE IS AT OR ABOVE AVERAGE FOR
COOLING TREND GOING INTO MID WEEK...AS WELL AS THE ONSET OF THE
NEXT PRECIPITATION EVENT LATER IN THE WEEK.

&&

.AJK WATCHES/WARNINGS/ADVISORIES...
PUBLIC...NONE.
MARINE...GALE WARNING FOR PKZ052.
         SMALL CRAFT ADVISORY FOR PKZ033-036-041>043-051.

&&

$$

BEZENEK/GARNER

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







000
FXAK67 PAJK 292338
AFDAJK

SOUTHEAST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE JUNEAU AK
338 PM AKDT MON SEP 29 2014

.SHORT TERM...THE WEAKENING VERTICALLY STACKED LOW OVER THE
SOUTHEAST GULF OF ALASKA WILL CONTINUE MOVING ACROSS NORTHERN HAIDA
GWAII THIS EVENING AND WILL DISSIPATE OVER THE BRITISH COLUMBIA
COAST BY TUESDAY MORNING. THE SHOWERS HAVE WEAKENED TO THE LEVEL
WHERE DO NOT THINK THUNDER WILL BE AROUND THROUGH THE EVENING OVER
THE SOUTHERN PANHANDLE.

OVER THE NORTHERN INNER CHANNELS REGION THIS EVENING AN TO THE
CENTRAL SHOWER ACTIVITY TAPERING OFF TO ISOLATED SHOWERS OR
EVEN JUST SOME SPRINKLES. THINK THAT SOUTHERN PANHANDLE WILL
SLOWLY TAPER OF OVERNIGHT.

MEANWHILE AN UPPER LEVEL TROUGH WITH A VIGOROUS SHORT WAVE MOVING
FROM THE SOUTH CENTRAL PORTION OF THE STATE INTO THE NORTHERN GULF
SPINNING UP A SURFACE LOW NEAR CAPE SUCKLING. THIS LOW IS EXPECTED
TO MOVE SOUTHEAST ALONG THE COASTLINE TO NEAR CAPE SPENSER BY
TUESDAY AFTERNOON. THE LOW SHOULD START TO WEAKEN ON TUESDAY. THE
TROUGH IS USHERING IN A BURST OF COLDER AIR ALOFT AND THIS WILL
START TO INFILTRATE THE NORTHEAST GULF COAST TUESDAY. THE AIR
ALOFT WILL ADD TO THE INSTABILITY ALLOWING FOR SOME SIGNIFICANT
SHOWERS POSSIBLY EVEN SOME THUNDER BUT WILL NOT PUT IN FORECAST.

WINDS ON SOUTH AND SOUTHWEST SIDE OF THIS SPIN UP LOW WILL
INCREASE TO GALE FORCE (35 KT) FOR THE NORTHERN OFFSHORE AND
MARINE ZONE 52...OTHERWISE LOOK FOR WINDS TO PICK UP TO SMALL CRAFT
BY TUESDAY AFTERNOON.

.LONG TERM...UPPER IMPULSE OBSERVED IN WV IMAGERY OVER THE NRN
GULF THIS AFTERNOON IS FORECAST TO MOVE ACROSS THE NRN PANHANDLE
AND INTO NRN B.C. BY TUE NIGHT. COLD AIR ALOFT /NEAR -30C AT 500
MB/ WILL SUPPORT A CONVECTIVE/SHOWERY REGIME WITH THE PASSING
TROUGH. HOWEVER...ANY THUNDERSTORM POTENTIAL SHOULD BE LOCATED E
OF THE CWA BY THE START OF THE LONG TERM PERIOD AS FORCING FOR
ASCENT ASSOCIATED WITH AN UPPER VORT LOBE EXITS THE REGION. A MUCH
COLDER LOW-LEVEL AIRMASS /-2 TO -8 AT 850 MB/ IS FORECAST TO
SPREAD SE ACROSS THE PANHANDLE AFTER THE PASSAGE OF THE UPPER
TROUGH. WITH SKIES CLEARING QUICKLY OVER YAKUTAT...LOWS ARE
FORECAST TO FALL TO NEAR 30F TUE NIGHT AS WELL AS WED NIGHT. IN
ADDITION...DRY AIR AND CLEAR SKIES SPREAD ESE ACROSS THE
REMAINDER OF THE CWA WED NIGHT...WHICH WILL FAVOR LOWS IN THE MID
30S TO AROUND 40 OVER MUCH OF THE AREA.

SURFACE PRESSURE PATTERN WILL BECOME CONDUCIVE FOR INCREASING OUTFLOW
WINDS THU THROUGH FRI AS HIGH PRESSURE BECOMES POSITIONED OVER
NWRN CANADA AND A LOW ENTERS THE SRN GULF. SMALL CRAFT NELY WINDS
WILL BE PROBABLE OVER CROSS SOUND...FREDERICK SOUND...AND SUMNER
STRAIT...WITH NLY WINDS UP TO 30 KT EXPECTED IN NRN AND SRN LYNN
CANAL. THOUGH ONLY COARSE DETERMINISTIC MODEL GUIDANCE IS
CURRENTLY AVAILABLE...12 KM NAM SHOWS 20-30 KT OF CROSS BARRIER
FLOW OCCURRING INVOF GASTINEAU CHANNEL. THIS FLOW COMBINED WITH A
ZONE OF FLOW REVERSAL ALOFT SIGNALS THE POTENTIAL FOR GUSTY WINDS
IN DOWNTOWN JUNEAU AND S DOUGLAS.

A FRONTAL BOUNDARY MOVES NNE INTO THE SRN PANHANDLE THU
NIGHT...WHICH WILL USHER IN STRENGTHENING SLY WINDS AND ANOTHER
ROUND OF MODERATE RAINFALL. THE ECMWF SHOWS A STRONGER SURFACE
CYCLONE OVER THE GULF COMPARED TO THE GFS/GEM. SMOOTHED OUT THESE
DIFFERENCES FOR THE TIME BEING WHILE TRANSITIONING TO THE WPC FRI-
SAT. IN GENERAL...THIS RESULTED IN ONLY MINOR CHANGES FROM
PREVIOUS LONG TERM FORECAST. CONFIDENCE IS AT OR ABOVE AVERAGE FOR
COOLING TREND GOING INTO MID WEEK...AS WELL AS THE ONSET OF THE
NEXT PRECIPITATION EVENT LATER IN THE WEEK.

&&

.AJK WATCHES/WARNINGS/ADVISORIES...
PUBLIC...NONE.
MARINE...GALE WARNING FOR PKZ052.
         SMALL CRAFT ADVISORY FOR PKZ033-036-041>043-051.

&&

$$

BEZENEK/GARNER

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







000
FXAK67 PAJK 292338
AFDAJK

SOUTHEAST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE JUNEAU AK
338 PM AKDT MON SEP 29 2014

.SHORT TERM...THE WEAKENING VERTICALLY STACKED LOW OVER THE
SOUTHEAST GULF OF ALASKA WILL CONTINUE MOVING ACROSS NORTHERN HAIDA
GWAII THIS EVENING AND WILL DISSIPATE OVER THE BRITISH COLUMBIA
COAST BY TUESDAY MORNING. THE SHOWERS HAVE WEAKENED TO THE LEVEL
WHERE DO NOT THINK THUNDER WILL BE AROUND THROUGH THE EVENING OVER
THE SOUTHERN PANHANDLE.

OVER THE NORTHERN INNER CHANNELS REGION THIS EVENING AN TO THE
CENTRAL SHOWER ACTIVITY TAPERING OFF TO ISOLATED SHOWERS OR
EVEN JUST SOME SPRINKLES. THINK THAT SOUTHERN PANHANDLE WILL
SLOWLY TAPER OF OVERNIGHT.

MEANWHILE AN UPPER LEVEL TROUGH WITH A VIGOROUS SHORT WAVE MOVING
FROM THE SOUTH CENTRAL PORTION OF THE STATE INTO THE NORTHERN GULF
SPINNING UP A SURFACE LOW NEAR CAPE SUCKLING. THIS LOW IS EXPECTED
TO MOVE SOUTHEAST ALONG THE COASTLINE TO NEAR CAPE SPENSER BY
TUESDAY AFTERNOON. THE LOW SHOULD START TO WEAKEN ON TUESDAY. THE
TROUGH IS USHERING IN A BURST OF COLDER AIR ALOFT AND THIS WILL
START TO INFILTRATE THE NORTHEAST GULF COAST TUESDAY. THE AIR
ALOFT WILL ADD TO THE INSTABILITY ALLOWING FOR SOME SIGNIFICANT
SHOWERS POSSIBLY EVEN SOME THUNDER BUT WILL NOT PUT IN FORECAST.

WINDS ON SOUTH AND SOUTHWEST SIDE OF THIS SPIN UP LOW WILL
INCREASE TO GALE FORCE (35 KT) FOR THE NORTHERN OFFSHORE AND
MARINE ZONE 52...OTHERWISE LOOK FOR WINDS TO PICK UP TO SMALL CRAFT
BY TUESDAY AFTERNOON.

.LONG TERM...UPPER IMPULSE OBSERVED IN WV IMAGERY OVER THE NRN
GULF THIS AFTERNOON IS FORECAST TO MOVE ACROSS THE NRN PANHANDLE
AND INTO NRN B.C. BY TUE NIGHT. COLD AIR ALOFT /NEAR -30C AT 500
MB/ WILL SUPPORT A CONVECTIVE/SHOWERY REGIME WITH THE PASSING
TROUGH. HOWEVER...ANY THUNDERSTORM POTENTIAL SHOULD BE LOCATED E
OF THE CWA BY THE START OF THE LONG TERM PERIOD AS FORCING FOR
ASCENT ASSOCIATED WITH AN UPPER VORT LOBE EXITS THE REGION. A MUCH
COLDER LOW-LEVEL AIRMASS /-2 TO -8 AT 850 MB/ IS FORECAST TO
SPREAD SE ACROSS THE PANHANDLE AFTER THE PASSAGE OF THE UPPER
TROUGH. WITH SKIES CLEARING QUICKLY OVER YAKUTAT...LOWS ARE
FORECAST TO FALL TO NEAR 30F TUE NIGHT AS WELL AS WED NIGHT. IN
ADDITION...DRY AIR AND CLEAR SKIES SPREAD ESE ACROSS THE
REMAINDER OF THE CWA WED NIGHT...WHICH WILL FAVOR LOWS IN THE MID
30S TO AROUND 40 OVER MUCH OF THE AREA.

SURFACE PRESSURE PATTERN WILL BECOME CONDUCIVE FOR INCREASING OUTFLOW
WINDS THU THROUGH FRI AS HIGH PRESSURE BECOMES POSITIONED OVER
NWRN CANADA AND A LOW ENTERS THE SRN GULF. SMALL CRAFT NELY WINDS
WILL BE PROBABLE OVER CROSS SOUND...FREDERICK SOUND...AND SUMNER
STRAIT...WITH NLY WINDS UP TO 30 KT EXPECTED IN NRN AND SRN LYNN
CANAL. THOUGH ONLY COARSE DETERMINISTIC MODEL GUIDANCE IS
CURRENTLY AVAILABLE...12 KM NAM SHOWS 20-30 KT OF CROSS BARRIER
FLOW OCCURRING INVOF GASTINEAU CHANNEL. THIS FLOW COMBINED WITH A
ZONE OF FLOW REVERSAL ALOFT SIGNALS THE POTENTIAL FOR GUSTY WINDS
IN DOWNTOWN JUNEAU AND S DOUGLAS.

A FRONTAL BOUNDARY MOVES NNE INTO THE SRN PANHANDLE THU
NIGHT...WHICH WILL USHER IN STRENGTHENING SLY WINDS AND ANOTHER
ROUND OF MODERATE RAINFALL. THE ECMWF SHOWS A STRONGER SURFACE
CYCLONE OVER THE GULF COMPARED TO THE GFS/GEM. SMOOTHED OUT THESE
DIFFERENCES FOR THE TIME BEING WHILE TRANSITIONING TO THE WPC FRI-
SAT. IN GENERAL...THIS RESULTED IN ONLY MINOR CHANGES FROM
PREVIOUS LONG TERM FORECAST. CONFIDENCE IS AT OR ABOVE AVERAGE FOR
COOLING TREND GOING INTO MID WEEK...AS WELL AS THE ONSET OF THE
NEXT PRECIPITATION EVENT LATER IN THE WEEK.

&&

.AJK WATCHES/WARNINGS/ADVISORIES...
PUBLIC...NONE.
MARINE...GALE WARNING FOR PKZ052.
         SMALL CRAFT ADVISORY FOR PKZ033-036-041>043-051.

&&

$$

BEZENEK/GARNER

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







000
FXAK67 PAJK 292338
AFDAJK

SOUTHEAST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE JUNEAU AK
338 PM AKDT MON SEP 29 2014

.SHORT TERM...THE WEAKENING VERTICALLY STACKED LOW OVER THE
SOUTHEAST GULF OF ALASKA WILL CONTINUE MOVING ACROSS NORTHERN HAIDA
GWAII THIS EVENING AND WILL DISSIPATE OVER THE BRITISH COLUMBIA
COAST BY TUESDAY MORNING. THE SHOWERS HAVE WEAKENED TO THE LEVEL
WHERE DO NOT THINK THUNDER WILL BE AROUND THROUGH THE EVENING OVER
THE SOUTHERN PANHANDLE.

OVER THE NORTHERN INNER CHANNELS REGION THIS EVENING AN TO THE
CENTRAL SHOWER ACTIVITY TAPERING OFF TO ISOLATED SHOWERS OR
EVEN JUST SOME SPRINKLES. THINK THAT SOUTHERN PANHANDLE WILL
SLOWLY TAPER OF OVERNIGHT.

MEANWHILE AN UPPER LEVEL TROUGH WITH A VIGOROUS SHORT WAVE MOVING
FROM THE SOUTH CENTRAL PORTION OF THE STATE INTO THE NORTHERN GULF
SPINNING UP A SURFACE LOW NEAR CAPE SUCKLING. THIS LOW IS EXPECTED
TO MOVE SOUTHEAST ALONG THE COASTLINE TO NEAR CAPE SPENSER BY
TUESDAY AFTERNOON. THE LOW SHOULD START TO WEAKEN ON TUESDAY. THE
TROUGH IS USHERING IN A BURST OF COLDER AIR ALOFT AND THIS WILL
START TO INFILTRATE THE NORTHEAST GULF COAST TUESDAY. THE AIR
ALOFT WILL ADD TO THE INSTABILITY ALLOWING FOR SOME SIGNIFICANT
SHOWERS POSSIBLY EVEN SOME THUNDER BUT WILL NOT PUT IN FORECAST.

WINDS ON SOUTH AND SOUTHWEST SIDE OF THIS SPIN UP LOW WILL
INCREASE TO GALE FORCE (35 KT) FOR THE NORTHERN OFFSHORE AND
MARINE ZONE 52...OTHERWISE LOOK FOR WINDS TO PICK UP TO SMALL CRAFT
BY TUESDAY AFTERNOON.

.LONG TERM...UPPER IMPULSE OBSERVED IN WV IMAGERY OVER THE NRN
GULF THIS AFTERNOON IS FORECAST TO MOVE ACROSS THE NRN PANHANDLE
AND INTO NRN B.C. BY TUE NIGHT. COLD AIR ALOFT /NEAR -30C AT 500
MB/ WILL SUPPORT A CONVECTIVE/SHOWERY REGIME WITH THE PASSING
TROUGH. HOWEVER...ANY THUNDERSTORM POTENTIAL SHOULD BE LOCATED E
OF THE CWA BY THE START OF THE LONG TERM PERIOD AS FORCING FOR
ASCENT ASSOCIATED WITH AN UPPER VORT LOBE EXITS THE REGION. A MUCH
COLDER LOW-LEVEL AIRMASS /-2 TO -8 AT 850 MB/ IS FORECAST TO
SPREAD SE ACROSS THE PANHANDLE AFTER THE PASSAGE OF THE UPPER
TROUGH. WITH SKIES CLEARING QUICKLY OVER YAKUTAT...LOWS ARE
FORECAST TO FALL TO NEAR 30F TUE NIGHT AS WELL AS WED NIGHT. IN
ADDITION...DRY AIR AND CLEAR SKIES SPREAD ESE ACROSS THE
REMAINDER OF THE CWA WED NIGHT...WHICH WILL FAVOR LOWS IN THE MID
30S TO AROUND 40 OVER MUCH OF THE AREA.

SURFACE PRESSURE PATTERN WILL BECOME CONDUCIVE FOR INCREASING OUTFLOW
WINDS THU THROUGH FRI AS HIGH PRESSURE BECOMES POSITIONED OVER
NWRN CANADA AND A LOW ENTERS THE SRN GULF. SMALL CRAFT NELY WINDS
WILL BE PROBABLE OVER CROSS SOUND...FREDERICK SOUND...AND SUMNER
STRAIT...WITH NLY WINDS UP TO 30 KT EXPECTED IN NRN AND SRN LYNN
CANAL. THOUGH ONLY COARSE DETERMINISTIC MODEL GUIDANCE IS
CURRENTLY AVAILABLE...12 KM NAM SHOWS 20-30 KT OF CROSS BARRIER
FLOW OCCURRING INVOF GASTINEAU CHANNEL. THIS FLOW COMBINED WITH A
ZONE OF FLOW REVERSAL ALOFT SIGNALS THE POTENTIAL FOR GUSTY WINDS
IN DOWNTOWN JUNEAU AND S DOUGLAS.

A FRONTAL BOUNDARY MOVES NNE INTO THE SRN PANHANDLE THU
NIGHT...WHICH WILL USHER IN STRENGTHENING SLY WINDS AND ANOTHER
ROUND OF MODERATE RAINFALL. THE ECMWF SHOWS A STRONGER SURFACE
CYCLONE OVER THE GULF COMPARED TO THE GFS/GEM. SMOOTHED OUT THESE
DIFFERENCES FOR THE TIME BEING WHILE TRANSITIONING TO THE WPC FRI-
SAT. IN GENERAL...THIS RESULTED IN ONLY MINOR CHANGES FROM
PREVIOUS LONG TERM FORECAST. CONFIDENCE IS AT OR ABOVE AVERAGE FOR
COOLING TREND GOING INTO MID WEEK...AS WELL AS THE ONSET OF THE
NEXT PRECIPITATION EVENT LATER IN THE WEEK.

&&

.AJK WATCHES/WARNINGS/ADVISORIES...
PUBLIC...NONE.
MARINE...GALE WARNING FOR PKZ052.
         SMALL CRAFT ADVISORY FOR PKZ033-036-041>043-051.

&&

$$

BEZENEK/GARNER

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







000
FXAK69 PAFG 292203
AFDAFG

NORTHERN ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE FAIRBANKS AK
203 PM AKDT MON SEP 29 2014

.DISCUSSION...
MODELS INITIALIZED WELL AND CONTINUE TO PERFORM WELL IN THE SHORT
TERM AS WELL AS THE MID TERM. CONSIDERABLE DIFFERENCES EMERGE BY
NEXT WEEKEND WITH LARGE AMPLITUDE PATTERN EVOLUTION.

ALOFT AT 500 HPA...A 524 DAM LOW 100 NM NORTH OF BARROW CONTINUES TO
ANCHOR THE LONG WAVE TROUGH EXTENDING SOUTH THROUGH THE EASTERN
INTERIOR. THE LOW MOVES SOUTH AND EAST AND WILL BE LOCATED OVER
PRUDHOE BAY TUESDAY MORNING WITH THE TROUGH PUSHING OVER THE ALCAN
BORDER. A STRONG RIDGE CONTINUES TO BUILD IN THE EASTERN BERING
SEA AND BUILDS NORTH AND WEST INTO THE NORTHERN BERING SEA BY MID
WEEK AND OVER SIBERIA BY WEEKS END. A VERY AMPLIFIED PATTERN SETS
UP THROUGH NEXT WEEKEND AS THE LONG WAVE TROUGH DEEPENS AND
RETROGRADES BACK WEST INTO ALASKA AS THE RIDGE BUILDS OVER
SIBERIA. DEEP AND COLD TROUGH SETTLES OVER ALASKA NEXT WEEK.

ON THE SURFACE A 996 MB LOW APPROXIMATELY 150 NM NORTHWEST OF
BARROW WILL CONTINUE TO WEAKEN TO AROUND 1005 MB AS IT MOVES NORTH
AND EAST INTO THE CENTRAL BEAUFORT SEA TUESDAY MORNING. ANOTHER
WEAK LOW FORMS OVER THE EASTERN NORTH SLOPE COASTAL WATERS TUESDAY
EVENING AND WILL MOVE INTO THE BEAUFORT SEA AS A 1005 MB LOW AND
BE LOCATED APPROXIMATELY 200 NM NORTH OF DEMARCATION POINT BY
WEDNESDAY MORNING.

AS THE LOW MOVES NORTHEAST AND WEAKENS THE GALE FORCE WINDS IN THE
SOUTHERN CHUKCHI SEA AND SOUTH OF ICY CAPE WILL DIMINISH TO SMALL
CRAFT LEVELS TONIGHT. EXPECT SMALL CRAFT LEVEL WINDS TO BUILD IN
THE COASTAL WATERS NORTH OF ICY CAPE LATE TONIGHT AND TOMORROW.
WINDS ALONG THE SEWARD PENINSULA WEST OF CAPE ESPENBERG AND
KOTZEBUE SOUND WILL DIMINISH TONIGHT. HIGH SURF ADVISORIES REMAIN
IN EFFECT FOR ZONES 207...209...201 AND WILL BE IN EFFECT TOMORROW
FOR ZONE 202.

SEVERAL SHORTWAVES MOVING THROUGH THE NORTHWEST TO SOUTHEAST FLOW
ALOFT THROUGH THE WEEK WILL BRING SEVERAL PERIODS OF SNOW TO THE
NORTH SLOPE AND ESPECIALLY THE EASTERN BROOKS RANGE. SNOW TOTALS
IN THE EASTERN BROOKS RANGE MAY REACH OVER 1 FOOT BY
FRIDAY...HOWEVER NO PARTICULAR EVENT IS EXPECTED TO REACH ADVISORY
OR WARNING LEVELS. THE BROOKS RANGE WILL CAPTURE MUCH OF THE
MOISTURE MOVING OVER NORTHERN ALASKA SO ONLY SCATTERED SNOW AND
RAIN SHOWERS EXPECTED OVER THE INTERIOR. THE WEST COAST SOUTH OF
THE SEWARD PENINSULA WILL REMAIN UNDER THE INFLUENCE OF THE HIGH
PRESSURE OVER THE EASTERN BERING SEA AND SHOULD RECEIVE MINIMAL
PRECIPITATION THROUGH THE WEEK.

COASTAL HAZARD POTENTIAL DAYS 3 AND 4...
HIGH SURF ADVISORIES HOISTED FOR ZONES 207...209...201 AND ZONE
202. WINDS ARE EXPECTED TO GRADUALLY DIMINISH TONIGHT OVER THE
SOUTHERN CHUKCHI SEA...HOWEVER WINDS WILL INCREASE ALONG THE COAST
NORTH OF ICY CAPE LATE TONIGHT AND TOMORROW.

&&

.HYDROLOGY...NONE


&&

.AFG WATCHES/WARNINGS/ADVISORIES...
HIGH SURF ADVISORY FOR AKZ201-AKZ202-AKZ207-AKZ209.

SMALL CRAFT ADVISORY FOR PKZ215-PKZ220-PKZ230-PKZ235.

GALE WARNING FOR PKZ225.
&&

$$

CCC SEP 14




000
FXAK69 PAFG 292203
AFDAFG

NORTHERN ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE FAIRBANKS AK
203 PM AKDT MON SEP 29 2014

.DISCUSSION...
MODELS INITIALIZED WELL AND CONTINUE TO PERFORM WELL IN THE SHORT
TERM AS WELL AS THE MID TERM. CONSIDERABLE DIFFERENCES EMERGE BY
NEXT WEEKEND WITH LARGE AMPLITUDE PATTERN EVOLUTION.

ALOFT AT 500 HPA...A 524 DAM LOW 100 NM NORTH OF BARROW CONTINUES TO
ANCHOR THE LONG WAVE TROUGH EXTENDING SOUTH THROUGH THE EASTERN
INTERIOR. THE LOW MOVES SOUTH AND EAST AND WILL BE LOCATED OVER
PRUDHOE BAY TUESDAY MORNING WITH THE TROUGH PUSHING OVER THE ALCAN
BORDER. A STRONG RIDGE CONTINUES TO BUILD IN THE EASTERN BERING
SEA AND BUILDS NORTH AND WEST INTO THE NORTHERN BERING SEA BY MID
WEEK AND OVER SIBERIA BY WEEKS END. A VERY AMPLIFIED PATTERN SETS
UP THROUGH NEXT WEEKEND AS THE LONG WAVE TROUGH DEEPENS AND
RETROGRADES BACK WEST INTO ALASKA AS THE RIDGE BUILDS OVER
SIBERIA. DEEP AND COLD TROUGH SETTLES OVER ALASKA NEXT WEEK.

ON THE SURFACE A 996 MB LOW APPROXIMATELY 150 NM NORTHWEST OF
BARROW WILL CONTINUE TO WEAKEN TO AROUND 1005 MB AS IT MOVES NORTH
AND EAST INTO THE CENTRAL BEAUFORT SEA TUESDAY MORNING. ANOTHER
WEAK LOW FORMS OVER THE EASTERN NORTH SLOPE COASTAL WATERS TUESDAY
EVENING AND WILL MOVE INTO THE BEAUFORT SEA AS A 1005 MB LOW AND
BE LOCATED APPROXIMATELY 200 NM NORTH OF DEMARCATION POINT BY
WEDNESDAY MORNING.

AS THE LOW MOVES NORTHEAST AND WEAKENS THE GALE FORCE WINDS IN THE
SOUTHERN CHUKCHI SEA AND SOUTH OF ICY CAPE WILL DIMINISH TO SMALL
CRAFT LEVELS TONIGHT. EXPECT SMALL CRAFT LEVEL WINDS TO BUILD IN
THE COASTAL WATERS NORTH OF ICY CAPE LATE TONIGHT AND TOMORROW.
WINDS ALONG THE SEWARD PENINSULA WEST OF CAPE ESPENBERG AND
KOTZEBUE SOUND WILL DIMINISH TONIGHT. HIGH SURF ADVISORIES REMAIN
IN EFFECT FOR ZONES 207...209...201 AND WILL BE IN EFFECT TOMORROW
FOR ZONE 202.

SEVERAL SHORTWAVES MOVING THROUGH THE NORTHWEST TO SOUTHEAST FLOW
ALOFT THROUGH THE WEEK WILL BRING SEVERAL PERIODS OF SNOW TO THE
NORTH SLOPE AND ESPECIALLY THE EASTERN BROOKS RANGE. SNOW TOTALS
IN THE EASTERN BROOKS RANGE MAY REACH OVER 1 FOOT BY
FRIDAY...HOWEVER NO PARTICULAR EVENT IS EXPECTED TO REACH ADVISORY
OR WARNING LEVELS. THE BROOKS RANGE WILL CAPTURE MUCH OF THE
MOISTURE MOVING OVER NORTHERN ALASKA SO ONLY SCATTERED SNOW AND
RAIN SHOWERS EXPECTED OVER THE INTERIOR. THE WEST COAST SOUTH OF
THE SEWARD PENINSULA WILL REMAIN UNDER THE INFLUENCE OF THE HIGH
PRESSURE OVER THE EASTERN BERING SEA AND SHOULD RECEIVE MINIMAL
PRECIPITATION THROUGH THE WEEK.

COASTAL HAZARD POTENTIAL DAYS 3 AND 4...
HIGH SURF ADVISORIES HOISTED FOR ZONES 207...209...201 AND ZONE
202. WINDS ARE EXPECTED TO GRADUALLY DIMINISH TONIGHT OVER THE
SOUTHERN CHUKCHI SEA...HOWEVER WINDS WILL INCREASE ALONG THE COAST
NORTH OF ICY CAPE LATE TONIGHT AND TOMORROW.

&&

.HYDROLOGY...NONE


&&

.AFG WATCHES/WARNINGS/ADVISORIES...
HIGH SURF ADVISORY FOR AKZ201-AKZ202-AKZ207-AKZ209.

SMALL CRAFT ADVISORY FOR PKZ215-PKZ220-PKZ230-PKZ235.

GALE WARNING FOR PKZ225.
&&

$$

CCC SEP 14




000
FXAK69 PAFG 292203
AFDAFG

NORTHERN ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE FAIRBANKS AK
203 PM AKDT MON SEP 29 2014

.DISCUSSION...
MODELS INITIALIZED WELL AND CONTINUE TO PERFORM WELL IN THE SHORT
TERM AS WELL AS THE MID TERM. CONSIDERABLE DIFFERENCES EMERGE BY
NEXT WEEKEND WITH LARGE AMPLITUDE PATTERN EVOLUTION.

ALOFT AT 500 HPA...A 524 DAM LOW 100 NM NORTH OF BARROW CONTINUES TO
ANCHOR THE LONG WAVE TROUGH EXTENDING SOUTH THROUGH THE EASTERN
INTERIOR. THE LOW MOVES SOUTH AND EAST AND WILL BE LOCATED OVER
PRUDHOE BAY TUESDAY MORNING WITH THE TROUGH PUSHING OVER THE ALCAN
BORDER. A STRONG RIDGE CONTINUES TO BUILD IN THE EASTERN BERING
SEA AND BUILDS NORTH AND WEST INTO THE NORTHERN BERING SEA BY MID
WEEK AND OVER SIBERIA BY WEEKS END. A VERY AMPLIFIED PATTERN SETS
UP THROUGH NEXT WEEKEND AS THE LONG WAVE TROUGH DEEPENS AND
RETROGRADES BACK WEST INTO ALASKA AS THE RIDGE BUILDS OVER
SIBERIA. DEEP AND COLD TROUGH SETTLES OVER ALASKA NEXT WEEK.

ON THE SURFACE A 996 MB LOW APPROXIMATELY 150 NM NORTHWEST OF
BARROW WILL CONTINUE TO WEAKEN TO AROUND 1005 MB AS IT MOVES NORTH
AND EAST INTO THE CENTRAL BEAUFORT SEA TUESDAY MORNING. ANOTHER
WEAK LOW FORMS OVER THE EASTERN NORTH SLOPE COASTAL WATERS TUESDAY
EVENING AND WILL MOVE INTO THE BEAUFORT SEA AS A 1005 MB LOW AND
BE LOCATED APPROXIMATELY 200 NM NORTH OF DEMARCATION POINT BY
WEDNESDAY MORNING.

AS THE LOW MOVES NORTHEAST AND WEAKENS THE GALE FORCE WINDS IN THE
SOUTHERN CHUKCHI SEA AND SOUTH OF ICY CAPE WILL DIMINISH TO SMALL
CRAFT LEVELS TONIGHT. EXPECT SMALL CRAFT LEVEL WINDS TO BUILD IN
THE COASTAL WATERS NORTH OF ICY CAPE LATE TONIGHT AND TOMORROW.
WINDS ALONG THE SEWARD PENINSULA WEST OF CAPE ESPENBERG AND
KOTZEBUE SOUND WILL DIMINISH TONIGHT. HIGH SURF ADVISORIES REMAIN
IN EFFECT FOR ZONES 207...209...201 AND WILL BE IN EFFECT TOMORROW
FOR ZONE 202.

SEVERAL SHORTWAVES MOVING THROUGH THE NORTHWEST TO SOUTHEAST FLOW
ALOFT THROUGH THE WEEK WILL BRING SEVERAL PERIODS OF SNOW TO THE
NORTH SLOPE AND ESPECIALLY THE EASTERN BROOKS RANGE. SNOW TOTALS
IN THE EASTERN BROOKS RANGE MAY REACH OVER 1 FOOT BY
FRIDAY...HOWEVER NO PARTICULAR EVENT IS EXPECTED TO REACH ADVISORY
OR WARNING LEVELS. THE BROOKS RANGE WILL CAPTURE MUCH OF THE
MOISTURE MOVING OVER NORTHERN ALASKA SO ONLY SCATTERED SNOW AND
RAIN SHOWERS EXPECTED OVER THE INTERIOR. THE WEST COAST SOUTH OF
THE SEWARD PENINSULA WILL REMAIN UNDER THE INFLUENCE OF THE HIGH
PRESSURE OVER THE EASTERN BERING SEA AND SHOULD RECEIVE MINIMAL
PRECIPITATION THROUGH THE WEEK.

COASTAL HAZARD POTENTIAL DAYS 3 AND 4...
HIGH SURF ADVISORIES HOISTED FOR ZONES 207...209...201 AND ZONE
202. WINDS ARE EXPECTED TO GRADUALLY DIMINISH TONIGHT OVER THE
SOUTHERN CHUKCHI SEA...HOWEVER WINDS WILL INCREASE ALONG THE COAST
NORTH OF ICY CAPE LATE TONIGHT AND TOMORROW.

&&

.HYDROLOGY...NONE


&&

.AFG WATCHES/WARNINGS/ADVISORIES...
HIGH SURF ADVISORY FOR AKZ201-AKZ202-AKZ207-AKZ209.

SMALL CRAFT ADVISORY FOR PKZ215-PKZ220-PKZ230-PKZ235.

GALE WARNING FOR PKZ225.
&&

$$

CCC SEP 14




000
FXAK69 PAFG 292203
AFDAFG

NORTHERN ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE FAIRBANKS AK
203 PM AKDT MON SEP 29 2014

.DISCUSSION...
MODELS INITIALIZED WELL AND CONTINUE TO PERFORM WELL IN THE SHORT
TERM AS WELL AS THE MID TERM. CONSIDERABLE DIFFERENCES EMERGE BY
NEXT WEEKEND WITH LARGE AMPLITUDE PATTERN EVOLUTION.

ALOFT AT 500 HPA...A 524 DAM LOW 100 NM NORTH OF BARROW CONTINUES TO
ANCHOR THE LONG WAVE TROUGH EXTENDING SOUTH THROUGH THE EASTERN
INTERIOR. THE LOW MOVES SOUTH AND EAST AND WILL BE LOCATED OVER
PRUDHOE BAY TUESDAY MORNING WITH THE TROUGH PUSHING OVER THE ALCAN
BORDER. A STRONG RIDGE CONTINUES TO BUILD IN THE EASTERN BERING
SEA AND BUILDS NORTH AND WEST INTO THE NORTHERN BERING SEA BY MID
WEEK AND OVER SIBERIA BY WEEKS END. A VERY AMPLIFIED PATTERN SETS
UP THROUGH NEXT WEEKEND AS THE LONG WAVE TROUGH DEEPENS AND
RETROGRADES BACK WEST INTO ALASKA AS THE RIDGE BUILDS OVER
SIBERIA. DEEP AND COLD TROUGH SETTLES OVER ALASKA NEXT WEEK.

ON THE SURFACE A 996 MB LOW APPROXIMATELY 150 NM NORTHWEST OF
BARROW WILL CONTINUE TO WEAKEN TO AROUND 1005 MB AS IT MOVES NORTH
AND EAST INTO THE CENTRAL BEAUFORT SEA TUESDAY MORNING. ANOTHER
WEAK LOW FORMS OVER THE EASTERN NORTH SLOPE COASTAL WATERS TUESDAY
EVENING AND WILL MOVE INTO THE BEAUFORT SEA AS A 1005 MB LOW AND
BE LOCATED APPROXIMATELY 200 NM NORTH OF DEMARCATION POINT BY
WEDNESDAY MORNING.

AS THE LOW MOVES NORTHEAST AND WEAKENS THE GALE FORCE WINDS IN THE
SOUTHERN CHUKCHI SEA AND SOUTH OF ICY CAPE WILL DIMINISH TO SMALL
CRAFT LEVELS TONIGHT. EXPECT SMALL CRAFT LEVEL WINDS TO BUILD IN
THE COASTAL WATERS NORTH OF ICY CAPE LATE TONIGHT AND TOMORROW.
WINDS ALONG THE SEWARD PENINSULA WEST OF CAPE ESPENBERG AND
KOTZEBUE SOUND WILL DIMINISH TONIGHT. HIGH SURF ADVISORIES REMAIN
IN EFFECT FOR ZONES 207...209...201 AND WILL BE IN EFFECT TOMORROW
FOR ZONE 202.

SEVERAL SHORTWAVES MOVING THROUGH THE NORTHWEST TO SOUTHEAST FLOW
ALOFT THROUGH THE WEEK WILL BRING SEVERAL PERIODS OF SNOW TO THE
NORTH SLOPE AND ESPECIALLY THE EASTERN BROOKS RANGE. SNOW TOTALS
IN THE EASTERN BROOKS RANGE MAY REACH OVER 1 FOOT BY
FRIDAY...HOWEVER NO PARTICULAR EVENT IS EXPECTED TO REACH ADVISORY
OR WARNING LEVELS. THE BROOKS RANGE WILL CAPTURE MUCH OF THE
MOISTURE MOVING OVER NORTHERN ALASKA SO ONLY SCATTERED SNOW AND
RAIN SHOWERS EXPECTED OVER THE INTERIOR. THE WEST COAST SOUTH OF
THE SEWARD PENINSULA WILL REMAIN UNDER THE INFLUENCE OF THE HIGH
PRESSURE OVER THE EASTERN BERING SEA AND SHOULD RECEIVE MINIMAL
PRECIPITATION THROUGH THE WEEK.

COASTAL HAZARD POTENTIAL DAYS 3 AND 4...
HIGH SURF ADVISORIES HOISTED FOR ZONES 207...209...201 AND ZONE
202. WINDS ARE EXPECTED TO GRADUALLY DIMINISH TONIGHT OVER THE
SOUTHERN CHUKCHI SEA...HOWEVER WINDS WILL INCREASE ALONG THE COAST
NORTH OF ICY CAPE LATE TONIGHT AND TOMORROW.

&&

.HYDROLOGY...NONE


&&

.AFG WATCHES/WARNINGS/ADVISORIES...
HIGH SURF ADVISORY FOR AKZ201-AKZ202-AKZ207-AKZ209.

SMALL CRAFT ADVISORY FOR PKZ215-PKZ220-PKZ230-PKZ235.

GALE WARNING FOR PKZ225.
&&

$$

CCC SEP 14




000
FXAK68 PAFC 292156
AFDAFC

SOUTHCENTRAL AND SOUTHWEST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE ANCHORAGE AK
156 PM AKDT MON SEP 29 2014

ANALYSIS AND UPPER LEVELS...WATER VAPOR IMAGERY SHOWS A DIGGING
TROUGH MOVING EAST ACROSS THE CENTRAL MAINLAND. SHOWERS HAVE
STARTED TO DEVELOP EAST OF THE ALASKA RANGE IN RESPONSE TO STRONG
UPPER DYNAMICS ASSOCIATED WITH THIS FEATURE. BRISK GAP FLOWS WHERE
EVIDENT ACROSS MUCH OF SOUTHCENTRAL ESPECIALLY ALONG THE NORTH
GULF COAST AND EASTERN KENAI PENINSULA.

FURTHER WEST...AN UPPER RIDGE CONTINUED OVER THE NORTHERN BERING
SEA. A BROAD UPPER LEVEL LOW AND ITS ASSOCIATED SURFACE LOW WAS
EVIDENT SOUTH OF THE ALEUTIANS. THE SURFACE LOW AND ITS
ASSOCIATED FRONTAL TROUGH PRODUCED SOME LIGHT RAIN AS WELL AS
BRISK EASTERLY GALES ACROSS THE CENTRAL ALEUTIANS. WITH THE
EXCEPTION OF RAIN AND SNOW SHOWERS ALONG THE ALEUTIAN RANGE...MUCH
OF SW ALASKA WAS DRY.

&&

MODEL DISCUSSION...THE MODEL HANDING OF UPPER LEVEL AS WELL AS
SURFACE SYNOPTIC FEATURES ARE IN FAIRLY GOOD AGREEMENT THROUGH THE
SHORT TERM. DIFFERENCES HOWEVER DO ARISE THU SOUTH OF THE GULF
WITH THE HANDLING OF THE NEXT LOW COMPLEX. THE 00Z ECMWF RAPIDLY
DEVELOPED AN OLD TROPICAL SYSTEM AND MOVED SOUTH OF THE GULF ON
THU AFTERNOON. THE 12Z ECMWF HAS COME IN LINE WITH THE OTHER
GLOBAL MODELS WHICH DEPICT A BROADER/ELONGATED AND MUCH WEAKER
LOW PRESSURE TROUGH SOUTH OF THE GULF. THE NAM WILL BE INITIALLY
USED THROUGH WED IN THE EAST TO CAPTURE OUTFLOW CONDITIONS...THEN
WILL TRANSITION INTO THE GFS. OUT WEST...THE GFS WILL BE USED FOR
THE AFTERNOON PACKAGE.

&&

.SHORT TERM FORECAST...
SOUTHCENTRAL ALASKA...WINDS WILL BE THE MAIN WEATHER FEATURE OVER
THE NEXT 24 TO 36 HRS. WINDS WILL PICK UP ACROSS MUCH OF THE AREA
THROUGH THIS EVENING WITH THE ONSET OF SUPPORTING NW FLOW AND
SUBSIDENCE WITH THE PASSAGE OF THE UPPER TROUGH. VERY STRONG GAP
FLOWS WILL DEVELOP TONIGHT ACROSS MUCH OF THE NORTH GULF AND
EASTERN KENAI PEN AS PRESSURE AND TEMPS GRADIENTS INCREASE ACROSS
THE AREA. WINDS WILL BE AT A MAXIMUM DURING THE LATE TONIGHT AND
TUE MORNING THEN SLOWLY WEAKEN TUE AFTERNOON AS THE SURFACE AND
UPPER SUPPORT WANES.

STRONG DYNAMICS ACCOMPANYING THE TROUGH WILL PRODUCE RAIN AND
SNOW SHOWERS. HIGHER ELEVATIONS...ESPECIALLY OF THE NORTHERN AND
EASTERN COPPER RIVER BASIN WILL SEE SNOW WITH MEASURABLE
ACCUMULATIONS TONIGHT. PRECIPITATION WILL DECREASE ACROSS THE
AREA AS COLDER AND DRIER AIR SPREAD EAST BEHIND THE TROUGH.

SOUTHWEST ALASKA...CONDITIONS WILL BE RELATIVELY DRY ACROSS SW
ALASKA OVER THE NEXT COUPLE OF DAYS AS HIGH PRESSURE BUILDS OVER
THE AREA. FOG WILL BECOME A CONCERN FOR THE DELTA AND ADJACENT
COAST. THE NORTHERLY OFFSHORE FLOW WILL LIKELY HAMPER ANY FOG
DEVELOPMENT OVER BRISTOL BAY OVER THE NEXT DAY OR SO. BRISK
EASTERLY FLOW ASSOCIATED WITH A LOW COMPLEX OVER THE NORTH PACIFIC
WILL CONTINUE ACROSS THE AK PEN THROUGH WED.

BERING SEA/ALEUTIANS...RAIN AND WIND WILL HOLD ON ALONG THE
CENTRAL ALEUTIANS UNTIL THE LOW TO THE SOUTH FINALLY DROPS FURTHER
INTO THE PACIFIC LATER TONIGHT. OTHERWISE HIGH PRESSURE WILL BUILD
OVER THE CENTRAL BERING SEA AND CONTINUE TO STRENGTHEN THROUGH MID
WEEK...SETTING UP A BLOCKING PATTERN AND PROVIDING VERY QUIET
CONDITIONS FOR MOST OF THE REGION. THE ONE EXCEPTION WILL BE THE
WESTERN ALEUTIANS ON THE UPSTREAM SIDE OF THE RIDGE WHICH WILL SEE
IMPACTS FROM A SYSTEM PASSING TO THE WEST MID WEEK.

&&

.LONG TERM FORECAST (FRI OCT 3 - MON OCT 6)...

ON FRIDAY...A HIGHLY AMPLIFIED PATTERN WILL BE DEVELOPING ACROSS
THE REGION...WITH A BLOCKING RIDGE ACROSS THE CENTRAL BERING
EXTENDING INTO SIBERIA...AND A LARGE TROUGH ACROSS THE MAINLAND.
ARCTIC AIR WILL ACCOMPANY THE TROUGH...WITH STEADILY DROPPING
TEMPERATURES HEADING INTO THE WEEKEND. THE PATTERN WILL GENERALLY
BE DRY...BUT THERE IS THE THREAT FOR SNOW AND SNOW SHOWERS ACROSS
MOST OF SOUTHCENTRAL BY THE WEEKEND...ESPECIALLY ACROSS THE COPPER
BASIN. THERE CONTINUES TO REMAIN UNCERTAINTY WITH A LOW MOVING
THROUGH THE EASTERN GULF OF ALASKA...SO A CONSERVATIVE MIDDLE
GROUND APPROACH WAS TAKEN WITH THE PRECIPITATION FORECAST. BY
MONDAY...UNCERTAINTY IN THE PATTERN GROWS IN MAGNITUDE QUICKLY AS
THE TRACK OF NORTHWEST PACIFIC CYCLONES (POSSIBLY INCLUDING
RECURVING REMNANTS OF PACIFIC TROPICAL CYCLONES) MOVING INTO THE
BERING BECOMES HIGHLY ERRATIC...THUS RESULTING IN SYNOPTIC SCALE
DISAGREEMENT AMONG THE VARIOUS GLOBAL NUMERICAL MODELS. WITH THAT
SAID...THE COLDEST TEMPS OF THE FALL CAN BE EXPECTED BY THIS
WEEKEND.

- AHSENMACHER

&&


.AFC WATCHES/WARNINGS/ADVISORIES...
PUBLIC...NONE.
MARINE...GALE WARNING...119 120 121 126 127 129 130 131 172 174
176 351. FIRE WEATHER...NONE.

&&

$$

RMC/AHSENMACHER SEP 14



000
FXAK67 PAJK 291335
AFDAJK

SOUTHEAST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE JUNEAU AK
535 AM AKDT MON SEP 29 2014

.SHORT TERM...DRIER NIGHT ACROSS THE AREA COMPARED TO 24 HOURS
AGO. THE FRONT THAT BROUGHT ALL THE WET WEATHER YESTERDAY IS NOW
WELL INTO CANADA. ALL THAT WE ARE LEFT WITH IS THE REMAINING
PARENT LOW WHICH IS STILL SPINNING AWAY IN THE SE GULF, AND THE
SHOWERS THAT ARE ROTATING AROUND IT. THE VORTICITY ASSOCIATED
WITH THE LOW AS WELL AS SOME COOLER AIR ALOFT HAS DESTABILIZED THE
ATMOSPHERE OVER THE GULF ENOUGH THAT SOME OF THESE SHOWERS ARE
PRODUCING SOME LIGHTNING THIS MORNING.

FOR TODAY THE LOW OVER THE SE GULF WILL SLOWLY MOVE TOWARD DIXON
ENTRANCE AND FINALLY INTO CANADA THIS AFTERNOON TAKING ITS SHOWERS
WITH IT. SHOWERS WILL CONTINUE TO BE PROBABLE AS THE LOW MOVES
THROUGH WITH THE HIGHEST POPS EXPECTED IN THE SOUTHERN PANHANDLE.
EVEN THOUGH THE LOW IS WEAKENING, ENOUGH COOL AIR AND VORTICITY
ALOFT REMAIN FOR THE POSSIBILITY OF THUNDERSTORMS TO HAPPEN NEAR
THE LOW INTO THE AFTERNOON. AS SUCH STILL HAVE ISOLATED AND SLIGHT
CHANCE WORDING FOR THUNDERSTORMS TODAY ACROSS THE SE GULF AND
SOUTHERN PANHANDLE. NOT MUCH RAINFALL IS EXPECTED AS THE SHOWERS
ARE NOT GROUPED THAT CLOSE TOGETHER. WINDS REMAIN LOW AS PRESSURE
GRADIENTS ARE NEARLY NON EXISTENT.

FOCUS SHIFTS TONIGHT AS A NEW UPPER TROUGH DROPS DOWN FROM THE
ALASKAN INTERIOR INTO THE NORTHERN PANHANDLE. FIRST OFF THIS
TROUGH IS STRONG ENOUGH TO PRODUCE A NEW SURFACE LOW IN THE
NORTHERN GULF THIS EVENING. THIS WILL ONLY HELP IN THE SPREAD OF
MORE RAIN ACROSS THE NORTHERN PANHANDLE. THERE IS ALSO A DECENT
AMOUNT OF COOL AIR ALOFT WITH THIS TROUGH THAT MAY MAKE THE PRECIP
TAKE THE FORM OF SHOWERS OR AT LEAST STRATIFORM RAIN WITH EMBEDDED
CONVECTION. WAS NOT THAT IMPRESSED WITH WITH THE NUMBERS GIVEN FOR
CONVECTION INDEXES WITH THIS SYSTEM SO LEFT OUT ANY THUNDERSTORM
WORDING FOR NOW. IN ANY CASE YAKUTAT IS THE FIRST TO FEEL THE
EFFECTS WITH RAIN STARTING UP THIS EVENING AND CONTINUING THROUGH
THE NIGHT. THE RAIN WILL SPREAD TO THE REST OF THE NORTHERN
PANHANDLE LATE TONIGHT. RAINFALL AMOUNTS ARE NOT EXPECTED TO BE
VERY SIGNIFICANT FOR THIS TIME OF YEAR WITH ONLY A QUARTER TO HALF
AN INCH OF RAIN EXPECTED IN ANY 6 HOUR PERIOD.

THE SURFACE LOW WILL ALSO INCREASE PRESSURE GRADIENTS ACROSS THE
GULF. THE RESULT IS GALE FORCE WINDS IN THE CENTRAL AND NORTH
CENTRAL GULF TONIGHT AND SMALL CRAFT WINDS FOR QUITE A BIT OF THE
REST OF THE GULF. MOST OF THIS WIND WILL NOT MAKE IT TO THE COAST
TONIGHT AS GRADIENTS DO NOT STAY TIGHT ENOUGH AS YOU GET OVER THE
PANHANDLE. WAVES WILL ALSO BE ON THE INCREASE AS THE HIGHER WINDS
IN THE GULF WHIP SEAS UP TO 11 FEET IN THE NORTHERN AND CENTRAL
GULF.

SHORT RANGE MODELS WERE IN VERY GOOD AGREEMENT FOR THE NEXT 24
HOURS. MINOR DIFFERENCES ON STRENGTH OF FEATURES REPRESENTED BUT
THEY WERE OFTEN ONLY OFF BY A MB OR TWO FROM EACH OTHER. ELECTED
TO USE THE ECMWF AND GEM FOR OVERALL GUIDANCE TODAY BUT STEERED
MORE TOWARD GFS FOR GULF WINDS.

.LONG TERM...UPPER LEVEL TROUGH MOVING DOWN FROM THE AK INTERIOR
WILL BRING IN COLD AIR MASS OVER THE PANHANDLE. 850 MB TEMPS IN THE
-2 TO -6 C RANGE WILL EQUATE TO SURFACE LOW TEMPS IN THE LOW 30S.
THE SURFACE LOW FORMED IN THE NORTHERN GULF WILL MOVE QUICKLY TO
THE SOUTHEAST ALONG THE PANHANDLE COAST WEAKENING TO AN OPEN WAVE
TROUGH BY EARLY WEDNESDAY MORNING. SHOWERS FROM THIS SYSTEM WILL
SUBSIDE OVERNIGHT TUESDAY FROM NORTH TO SOUTH. AS WEAK HIGH
PRESSURE BUILDS IN BEHIND THE LOW SKIES WILL BEGIN TO CLEAR WITH
DRY WEATHER FOR THE PANHANDLE MID WEEK. THE COLD OVERNIGHT TEMPS
WILL CONTINUE WEDNESDAY NIGH7 WITH A LARGER DIURNAL RANGE FOR
WEDNESDAY FROM DAY TIME HEATING DUE TO THE CLEARER SKIES. BY THE
END OF THE WEEK ANOTHER STRONG LOW WILL MOVE INTO THE AK GULF
FROM THE PACIFIC WITH INCREASING WINDS WITH UPPER LEVEL SMALL
CRAFT TO GALES DEVELOPING. THIS SYSTEM HAS A MIX OF THE REMNANTS
OF TROPICAL STORM KAMMURI SO WILL HAVE LONG FETCH OF MOISTURE FOR
THE NEXT ROUND OF MODERATE TO HEAVY RAIN. THE SYSTEM WILL ALSO
MOVE IN WARMER AIR MASS FROM THE PACIFIC SO EXPECTING PRECIP TO
FALL AS RAIN. AS THE CLIPPER LOW MOVES SOUTHWARD WINDS ON TUESDAY
WILL BEGIN TO SHIFT FROM SOUTH TO NORTH WITH WINDS INCREASING BY
MID WEEK DUE TO TIGHTENING PRESSURE GRADIENT OVER THE INNER
CHANNELS BETWEEN HIGH OVER THE YUKON AND THE NEXT PACIFIC LOW.

MODELS STILL IN FAIR AGREEMENT FOR SYNOPTIC PATTERN THROUGH 84
HOURS. THE GEM HAS BEEN MOST CONSISTENT THE PAST FEW DAYS AND WAS
KEPT AS MAIN MODEL WITH A MIX OF SOME GFS. THIS BLEND WAS VERY
CLOSE TO INHERITED FORECAST SO LITTLE CHANGE RESULTED. FOR THE REST
OF THE EXTENDED RANGE FORECAST LEFT THE WPC ENSEMBLE BLEND. IN THESE
LATER PERIODS THE GFS HAS BEEN MORE CONSISTENT WHILE THE ECMWF
SHOWED SOME LARGE CHANGES WITH THE MOST RECENT RUN DROPPING THE
END OF WEEK LOW CENTER DOWN TO 957 MB, A 20 MB DIFFERENCE FROM THE
GFS. FORECAST CONFIDENCE IS ABOVE AVERAGE INITIALLY BUT DROPS
RAPIDLY BY MID WEEK.


&&

.AJK WATCHES/WARNINGS/ADVISORIES...
PUBLIC...NONE.
MARINE...GALE WARNING FOR PKZ052.
         SMALL CRAFT ADVISORY FOR PKZ043-051.
         SMALL CRAFT ADVISORY DUE TO SEAS FOR PKZ041-042.

&&

$$

EAL/PRB

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








000
FXAK67 PAJK 291335
AFDAJK

SOUTHEAST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE JUNEAU AK
535 AM AKDT MON SEP 29 2014

.SHORT TERM...DRIER NIGHT ACROSS THE AREA COMPARED TO 24 HOURS
AGO. THE FRONT THAT BROUGHT ALL THE WET WEATHER YESTERDAY IS NOW
WELL INTO CANADA. ALL THAT WE ARE LEFT WITH IS THE REMAINING
PARENT LOW WHICH IS STILL SPINNING AWAY IN THE SE GULF, AND THE
SHOWERS THAT ARE ROTATING AROUND IT. THE VORTICITY ASSOCIATED
WITH THE LOW AS WELL AS SOME COOLER AIR ALOFT HAS DESTABILIZED THE
ATMOSPHERE OVER THE GULF ENOUGH THAT SOME OF THESE SHOWERS ARE
PRODUCING SOME LIGHTNING THIS MORNING.

FOR TODAY THE LOW OVER THE SE GULF WILL SLOWLY MOVE TOWARD DIXON
ENTRANCE AND FINALLY INTO CANADA THIS AFTERNOON TAKING ITS SHOWERS
WITH IT. SHOWERS WILL CONTINUE TO BE PROBABLE AS THE LOW MOVES
THROUGH WITH THE HIGHEST POPS EXPECTED IN THE SOUTHERN PANHANDLE.
EVEN THOUGH THE LOW IS WEAKENING, ENOUGH COOL AIR AND VORTICITY
ALOFT REMAIN FOR THE POSSIBILITY OF THUNDERSTORMS TO HAPPEN NEAR
THE LOW INTO THE AFTERNOON. AS SUCH STILL HAVE ISOLATED AND SLIGHT
CHANCE WORDING FOR THUNDERSTORMS TODAY ACROSS THE SE GULF AND
SOUTHERN PANHANDLE. NOT MUCH RAINFALL IS EXPECTED AS THE SHOWERS
ARE NOT GROUPED THAT CLOSE TOGETHER. WINDS REMAIN LOW AS PRESSURE
GRADIENTS ARE NEARLY NON EXISTENT.

FOCUS SHIFTS TONIGHT AS A NEW UPPER TROUGH DROPS DOWN FROM THE
ALASKAN INTERIOR INTO THE NORTHERN PANHANDLE. FIRST OFF THIS
TROUGH IS STRONG ENOUGH TO PRODUCE A NEW SURFACE LOW IN THE
NORTHERN GULF THIS EVENING. THIS WILL ONLY HELP IN THE SPREAD OF
MORE RAIN ACROSS THE NORTHERN PANHANDLE. THERE IS ALSO A DECENT
AMOUNT OF COOL AIR ALOFT WITH THIS TROUGH THAT MAY MAKE THE PRECIP
TAKE THE FORM OF SHOWERS OR AT LEAST STRATIFORM RAIN WITH EMBEDDED
CONVECTION. WAS NOT THAT IMPRESSED WITH WITH THE NUMBERS GIVEN FOR
CONVECTION INDEXES WITH THIS SYSTEM SO LEFT OUT ANY THUNDERSTORM
WORDING FOR NOW. IN ANY CASE YAKUTAT IS THE FIRST TO FEEL THE
EFFECTS WITH RAIN STARTING UP THIS EVENING AND CONTINUING THROUGH
THE NIGHT. THE RAIN WILL SPREAD TO THE REST OF THE NORTHERN
PANHANDLE LATE TONIGHT. RAINFALL AMOUNTS ARE NOT EXPECTED TO BE
VERY SIGNIFICANT FOR THIS TIME OF YEAR WITH ONLY A QUARTER TO HALF
AN INCH OF RAIN EXPECTED IN ANY 6 HOUR PERIOD.

THE SURFACE LOW WILL ALSO INCREASE PRESSURE GRADIENTS ACROSS THE
GULF. THE RESULT IS GALE FORCE WINDS IN THE CENTRAL AND NORTH
CENTRAL GULF TONIGHT AND SMALL CRAFT WINDS FOR QUITE A BIT OF THE
REST OF THE GULF. MOST OF THIS WIND WILL NOT MAKE IT TO THE COAST
TONIGHT AS GRADIENTS DO NOT STAY TIGHT ENOUGH AS YOU GET OVER THE
PANHANDLE. WAVES WILL ALSO BE ON THE INCREASE AS THE HIGHER WINDS
IN THE GULF WHIP SEAS UP TO 11 FEET IN THE NORTHERN AND CENTRAL
GULF.

SHORT RANGE MODELS WERE IN VERY GOOD AGREEMENT FOR THE NEXT 24
HOURS. MINOR DIFFERENCES ON STRENGTH OF FEATURES REPRESENTED BUT
THEY WERE OFTEN ONLY OFF BY A MB OR TWO FROM EACH OTHER. ELECTED
TO USE THE ECMWF AND GEM FOR OVERALL GUIDANCE TODAY BUT STEERED
MORE TOWARD GFS FOR GULF WINDS.

.LONG TERM...UPPER LEVEL TROUGH MOVING DOWN FROM THE AK INTERIOR
WILL BRING IN COLD AIR MASS OVER THE PANHANDLE. 850 MB TEMPS IN THE
-2 TO -6 C RANGE WILL EQUATE TO SURFACE LOW TEMPS IN THE LOW 30S.
THE SURFACE LOW FORMED IN THE NORTHERN GULF WILL MOVE QUICKLY TO
THE SOUTHEAST ALONG THE PANHANDLE COAST WEAKENING TO AN OPEN WAVE
TROUGH BY EARLY WEDNESDAY MORNING. SHOWERS FROM THIS SYSTEM WILL
SUBSIDE OVERNIGHT TUESDAY FROM NORTH TO SOUTH. AS WEAK HIGH
PRESSURE BUILDS IN BEHIND THE LOW SKIES WILL BEGIN TO CLEAR WITH
DRY WEATHER FOR THE PANHANDLE MID WEEK. THE COLD OVERNIGHT TEMPS
WILL CONTINUE WEDNESDAY NIGH7 WITH A LARGER DIURNAL RANGE FOR
WEDNESDAY FROM DAY TIME HEATING DUE TO THE CLEARER SKIES. BY THE
END OF THE WEEK ANOTHER STRONG LOW WILL MOVE INTO THE AK GULF
FROM THE PACIFIC WITH INCREASING WINDS WITH UPPER LEVEL SMALL
CRAFT TO GALES DEVELOPING. THIS SYSTEM HAS A MIX OF THE REMNANTS
OF TROPICAL STORM KAMMURI SO WILL HAVE LONG FETCH OF MOISTURE FOR
THE NEXT ROUND OF MODERATE TO HEAVY RAIN. THE SYSTEM WILL ALSO
MOVE IN WARMER AIR MASS FROM THE PACIFIC SO EXPECTING PRECIP TO
FALL AS RAIN. AS THE CLIPPER LOW MOVES SOUTHWARD WINDS ON TUESDAY
WILL BEGIN TO SHIFT FROM SOUTH TO NORTH WITH WINDS INCREASING BY
MID WEEK DUE TO TIGHTENING PRESSURE GRADIENT OVER THE INNER
CHANNELS BETWEEN HIGH OVER THE YUKON AND THE NEXT PACIFIC LOW.

MODELS STILL IN FAIR AGREEMENT FOR SYNOPTIC PATTERN THROUGH 84
HOURS. THE GEM HAS BEEN MOST CONSISTENT THE PAST FEW DAYS AND WAS
KEPT AS MAIN MODEL WITH A MIX OF SOME GFS. THIS BLEND WAS VERY
CLOSE TO INHERITED FORECAST SO LITTLE CHANGE RESULTED. FOR THE REST
OF THE EXTENDED RANGE FORECAST LEFT THE WPC ENSEMBLE BLEND. IN THESE
LATER PERIODS THE GFS HAS BEEN MORE CONSISTENT WHILE THE ECMWF
SHOWED SOME LARGE CHANGES WITH THE MOST RECENT RUN DROPPING THE
END OF WEEK LOW CENTER DOWN TO 957 MB, A 20 MB DIFFERENCE FROM THE
GFS. FORECAST CONFIDENCE IS ABOVE AVERAGE INITIALLY BUT DROPS
RAPIDLY BY MID WEEK.


&&

.AJK WATCHES/WARNINGS/ADVISORIES...
PUBLIC...NONE.
MARINE...GALE WARNING FOR PKZ052.
         SMALL CRAFT ADVISORY FOR PKZ043-051.
         SMALL CRAFT ADVISORY DUE TO SEAS FOR PKZ041-042.

&&

$$

EAL/PRB

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








000
FXAK67 PAJK 291335
AFDAJK

SOUTHEAST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE JUNEAU AK
535 AM AKDT MON SEP 29 2014

.SHORT TERM...DRIER NIGHT ACROSS THE AREA COMPARED TO 24 HOURS
AGO. THE FRONT THAT BROUGHT ALL THE WET WEATHER YESTERDAY IS NOW
WELL INTO CANADA. ALL THAT WE ARE LEFT WITH IS THE REMAINING
PARENT LOW WHICH IS STILL SPINNING AWAY IN THE SE GULF, AND THE
SHOWERS THAT ARE ROTATING AROUND IT. THE VORTICITY ASSOCIATED
WITH THE LOW AS WELL AS SOME COOLER AIR ALOFT HAS DESTABILIZED THE
ATMOSPHERE OVER THE GULF ENOUGH THAT SOME OF THESE SHOWERS ARE
PRODUCING SOME LIGHTNING THIS MORNING.

FOR TODAY THE LOW OVER THE SE GULF WILL SLOWLY MOVE TOWARD DIXON
ENTRANCE AND FINALLY INTO CANADA THIS AFTERNOON TAKING ITS SHOWERS
WITH IT. SHOWERS WILL CONTINUE TO BE PROBABLE AS THE LOW MOVES
THROUGH WITH THE HIGHEST POPS EXPECTED IN THE SOUTHERN PANHANDLE.
EVEN THOUGH THE LOW IS WEAKENING, ENOUGH COOL AIR AND VORTICITY
ALOFT REMAIN FOR THE POSSIBILITY OF THUNDERSTORMS TO HAPPEN NEAR
THE LOW INTO THE AFTERNOON. AS SUCH STILL HAVE ISOLATED AND SLIGHT
CHANCE WORDING FOR THUNDERSTORMS TODAY ACROSS THE SE GULF AND
SOUTHERN PANHANDLE. NOT MUCH RAINFALL IS EXPECTED AS THE SHOWERS
ARE NOT GROUPED THAT CLOSE TOGETHER. WINDS REMAIN LOW AS PRESSURE
GRADIENTS ARE NEARLY NON EXISTENT.

FOCUS SHIFTS TONIGHT AS A NEW UPPER TROUGH DROPS DOWN FROM THE
ALASKAN INTERIOR INTO THE NORTHERN PANHANDLE. FIRST OFF THIS
TROUGH IS STRONG ENOUGH TO PRODUCE A NEW SURFACE LOW IN THE
NORTHERN GULF THIS EVENING. THIS WILL ONLY HELP IN THE SPREAD OF
MORE RAIN ACROSS THE NORTHERN PANHANDLE. THERE IS ALSO A DECENT
AMOUNT OF COOL AIR ALOFT WITH THIS TROUGH THAT MAY MAKE THE PRECIP
TAKE THE FORM OF SHOWERS OR AT LEAST STRATIFORM RAIN WITH EMBEDDED
CONVECTION. WAS NOT THAT IMPRESSED WITH WITH THE NUMBERS GIVEN FOR
CONVECTION INDEXES WITH THIS SYSTEM SO LEFT OUT ANY THUNDERSTORM
WORDING FOR NOW. IN ANY CASE YAKUTAT IS THE FIRST TO FEEL THE
EFFECTS WITH RAIN STARTING UP THIS EVENING AND CONTINUING THROUGH
THE NIGHT. THE RAIN WILL SPREAD TO THE REST OF THE NORTHERN
PANHANDLE LATE TONIGHT. RAINFALL AMOUNTS ARE NOT EXPECTED TO BE
VERY SIGNIFICANT FOR THIS TIME OF YEAR WITH ONLY A QUARTER TO HALF
AN INCH OF RAIN EXPECTED IN ANY 6 HOUR PERIOD.

THE SURFACE LOW WILL ALSO INCREASE PRESSURE GRADIENTS ACROSS THE
GULF. THE RESULT IS GALE FORCE WINDS IN THE CENTRAL AND NORTH
CENTRAL GULF TONIGHT AND SMALL CRAFT WINDS FOR QUITE A BIT OF THE
REST OF THE GULF. MOST OF THIS WIND WILL NOT MAKE IT TO THE COAST
TONIGHT AS GRADIENTS DO NOT STAY TIGHT ENOUGH AS YOU GET OVER THE
PANHANDLE. WAVES WILL ALSO BE ON THE INCREASE AS THE HIGHER WINDS
IN THE GULF WHIP SEAS UP TO 11 FEET IN THE NORTHERN AND CENTRAL
GULF.

SHORT RANGE MODELS WERE IN VERY GOOD AGREEMENT FOR THE NEXT 24
HOURS. MINOR DIFFERENCES ON STRENGTH OF FEATURES REPRESENTED BUT
THEY WERE OFTEN ONLY OFF BY A MB OR TWO FROM EACH OTHER. ELECTED
TO USE THE ECMWF AND GEM FOR OVERALL GUIDANCE TODAY BUT STEERED
MORE TOWARD GFS FOR GULF WINDS.

.LONG TERM...UPPER LEVEL TROUGH MOVING DOWN FROM THE AK INTERIOR
WILL BRING IN COLD AIR MASS OVER THE PANHANDLE. 850 MB TEMPS IN THE
-2 TO -6 C RANGE WILL EQUATE TO SURFACE LOW TEMPS IN THE LOW 30S.
THE SURFACE LOW FORMED IN THE NORTHERN GULF WILL MOVE QUICKLY TO
THE SOUTHEAST ALONG THE PANHANDLE COAST WEAKENING TO AN OPEN WAVE
TROUGH BY EARLY WEDNESDAY MORNING. SHOWERS FROM THIS SYSTEM WILL
SUBSIDE OVERNIGHT TUESDAY FROM NORTH TO SOUTH. AS WEAK HIGH
PRESSURE BUILDS IN BEHIND THE LOW SKIES WILL BEGIN TO CLEAR WITH
DRY WEATHER FOR THE PANHANDLE MID WEEK. THE COLD OVERNIGHT TEMPS
WILL CONTINUE WEDNESDAY NIGH7 WITH A LARGER DIURNAL RANGE FOR
WEDNESDAY FROM DAY TIME HEATING DUE TO THE CLEARER SKIES. BY THE
END OF THE WEEK ANOTHER STRONG LOW WILL MOVE INTO THE AK GULF
FROM THE PACIFIC WITH INCREASING WINDS WITH UPPER LEVEL SMALL
CRAFT TO GALES DEVELOPING. THIS SYSTEM HAS A MIX OF THE REMNANTS
OF TROPICAL STORM KAMMURI SO WILL HAVE LONG FETCH OF MOISTURE FOR
THE NEXT ROUND OF MODERATE TO HEAVY RAIN. THE SYSTEM WILL ALSO
MOVE IN WARMER AIR MASS FROM THE PACIFIC SO EXPECTING PRECIP TO
FALL AS RAIN. AS THE CLIPPER LOW MOVES SOUTHWARD WINDS ON TUESDAY
WILL BEGIN TO SHIFT FROM SOUTH TO NORTH WITH WINDS INCREASING BY
MID WEEK DUE TO TIGHTENING PRESSURE GRADIENT OVER THE INNER
CHANNELS BETWEEN HIGH OVER THE YUKON AND THE NEXT PACIFIC LOW.

MODELS STILL IN FAIR AGREEMENT FOR SYNOPTIC PATTERN THROUGH 84
HOURS. THE GEM HAS BEEN MOST CONSISTENT THE PAST FEW DAYS AND WAS
KEPT AS MAIN MODEL WITH A MIX OF SOME GFS. THIS BLEND WAS VERY
CLOSE TO INHERITED FORECAST SO LITTLE CHANGE RESULTED. FOR THE REST
OF THE EXTENDED RANGE FORECAST LEFT THE WPC ENSEMBLE BLEND. IN THESE
LATER PERIODS THE GFS HAS BEEN MORE CONSISTENT WHILE THE ECMWF
SHOWED SOME LARGE CHANGES WITH THE MOST RECENT RUN DROPPING THE
END OF WEEK LOW CENTER DOWN TO 957 MB, A 20 MB DIFFERENCE FROM THE
GFS. FORECAST CONFIDENCE IS ABOVE AVERAGE INITIALLY BUT DROPS
RAPIDLY BY MID WEEK.


&&

.AJK WATCHES/WARNINGS/ADVISORIES...
PUBLIC...NONE.
MARINE...GALE WARNING FOR PKZ052.
         SMALL CRAFT ADVISORY FOR PKZ043-051.
         SMALL CRAFT ADVISORY DUE TO SEAS FOR PKZ041-042.

&&

$$

EAL/PRB

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








000
FXAK67 PAJK 291335
AFDAJK

SOUTHEAST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE JUNEAU AK
535 AM AKDT MON SEP 29 2014

.SHORT TERM...DRIER NIGHT ACROSS THE AREA COMPARED TO 24 HOURS
AGO. THE FRONT THAT BROUGHT ALL THE WET WEATHER YESTERDAY IS NOW
WELL INTO CANADA. ALL THAT WE ARE LEFT WITH IS THE REMAINING
PARENT LOW WHICH IS STILL SPINNING AWAY IN THE SE GULF, AND THE
SHOWERS THAT ARE ROTATING AROUND IT. THE VORTICITY ASSOCIATED
WITH THE LOW AS WELL AS SOME COOLER AIR ALOFT HAS DESTABILIZED THE
ATMOSPHERE OVER THE GULF ENOUGH THAT SOME OF THESE SHOWERS ARE
PRODUCING SOME LIGHTNING THIS MORNING.

FOR TODAY THE LOW OVER THE SE GULF WILL SLOWLY MOVE TOWARD DIXON
ENTRANCE AND FINALLY INTO CANADA THIS AFTERNOON TAKING ITS SHOWERS
WITH IT. SHOWERS WILL CONTINUE TO BE PROBABLE AS THE LOW MOVES
THROUGH WITH THE HIGHEST POPS EXPECTED IN THE SOUTHERN PANHANDLE.
EVEN THOUGH THE LOW IS WEAKENING, ENOUGH COOL AIR AND VORTICITY
ALOFT REMAIN FOR THE POSSIBILITY OF THUNDERSTORMS TO HAPPEN NEAR
THE LOW INTO THE AFTERNOON. AS SUCH STILL HAVE ISOLATED AND SLIGHT
CHANCE WORDING FOR THUNDERSTORMS TODAY ACROSS THE SE GULF AND
SOUTHERN PANHANDLE. NOT MUCH RAINFALL IS EXPECTED AS THE SHOWERS
ARE NOT GROUPED THAT CLOSE TOGETHER. WINDS REMAIN LOW AS PRESSURE
GRADIENTS ARE NEARLY NON EXISTENT.

FOCUS SHIFTS TONIGHT AS A NEW UPPER TROUGH DROPS DOWN FROM THE
ALASKAN INTERIOR INTO THE NORTHERN PANHANDLE. FIRST OFF THIS
TROUGH IS STRONG ENOUGH TO PRODUCE A NEW SURFACE LOW IN THE
NORTHERN GULF THIS EVENING. THIS WILL ONLY HELP IN THE SPREAD OF
MORE RAIN ACROSS THE NORTHERN PANHANDLE. THERE IS ALSO A DECENT
AMOUNT OF COOL AIR ALOFT WITH THIS TROUGH THAT MAY MAKE THE PRECIP
TAKE THE FORM OF SHOWERS OR AT LEAST STRATIFORM RAIN WITH EMBEDDED
CONVECTION. WAS NOT THAT IMPRESSED WITH WITH THE NUMBERS GIVEN FOR
CONVECTION INDEXES WITH THIS SYSTEM SO LEFT OUT ANY THUNDERSTORM
WORDING FOR NOW. IN ANY CASE YAKUTAT IS THE FIRST TO FEEL THE
EFFECTS WITH RAIN STARTING UP THIS EVENING AND CONTINUING THROUGH
THE NIGHT. THE RAIN WILL SPREAD TO THE REST OF THE NORTHERN
PANHANDLE LATE TONIGHT. RAINFALL AMOUNTS ARE NOT EXPECTED TO BE
VERY SIGNIFICANT FOR THIS TIME OF YEAR WITH ONLY A QUARTER TO HALF
AN INCH OF RAIN EXPECTED IN ANY 6 HOUR PERIOD.

THE SURFACE LOW WILL ALSO INCREASE PRESSURE GRADIENTS ACROSS THE
GULF. THE RESULT IS GALE FORCE WINDS IN THE CENTRAL AND NORTH
CENTRAL GULF TONIGHT AND SMALL CRAFT WINDS FOR QUITE A BIT OF THE
REST OF THE GULF. MOST OF THIS WIND WILL NOT MAKE IT TO THE COAST
TONIGHT AS GRADIENTS DO NOT STAY TIGHT ENOUGH AS YOU GET OVER THE
PANHANDLE. WAVES WILL ALSO BE ON THE INCREASE AS THE HIGHER WINDS
IN THE GULF WHIP SEAS UP TO 11 FEET IN THE NORTHERN AND CENTRAL
GULF.

SHORT RANGE MODELS WERE IN VERY GOOD AGREEMENT FOR THE NEXT 24
HOURS. MINOR DIFFERENCES ON STRENGTH OF FEATURES REPRESENTED BUT
THEY WERE OFTEN ONLY OFF BY A MB OR TWO FROM EACH OTHER. ELECTED
TO USE THE ECMWF AND GEM FOR OVERALL GUIDANCE TODAY BUT STEERED
MORE TOWARD GFS FOR GULF WINDS.

.LONG TERM...UPPER LEVEL TROUGH MOVING DOWN FROM THE AK INTERIOR
WILL BRING IN COLD AIR MASS OVER THE PANHANDLE. 850 MB TEMPS IN THE
-2 TO -6 C RANGE WILL EQUATE TO SURFACE LOW TEMPS IN THE LOW 30S.
THE SURFACE LOW FORMED IN THE NORTHERN GULF WILL MOVE QUICKLY TO
THE SOUTHEAST ALONG THE PANHANDLE COAST WEAKENING TO AN OPEN WAVE
TROUGH BY EARLY WEDNESDAY MORNING. SHOWERS FROM THIS SYSTEM WILL
SUBSIDE OVERNIGHT TUESDAY FROM NORTH TO SOUTH. AS WEAK HIGH
PRESSURE BUILDS IN BEHIND THE LOW SKIES WILL BEGIN TO CLEAR WITH
DRY WEATHER FOR THE PANHANDLE MID WEEK. THE COLD OVERNIGHT TEMPS
WILL CONTINUE WEDNESDAY NIGH7 WITH A LARGER DIURNAL RANGE FOR
WEDNESDAY FROM DAY TIME HEATING DUE TO THE CLEARER SKIES. BY THE
END OF THE WEEK ANOTHER STRONG LOW WILL MOVE INTO THE AK GULF
FROM THE PACIFIC WITH INCREASING WINDS WITH UPPER LEVEL SMALL
CRAFT TO GALES DEVELOPING. THIS SYSTEM HAS A MIX OF THE REMNANTS
OF TROPICAL STORM KAMMURI SO WILL HAVE LONG FETCH OF MOISTURE FOR
THE NEXT ROUND OF MODERATE TO HEAVY RAIN. THE SYSTEM WILL ALSO
MOVE IN WARMER AIR MASS FROM THE PACIFIC SO EXPECTING PRECIP TO
FALL AS RAIN. AS THE CLIPPER LOW MOVES SOUTHWARD WINDS ON TUESDAY
WILL BEGIN TO SHIFT FROM SOUTH TO NORTH WITH WINDS INCREASING BY
MID WEEK DUE TO TIGHTENING PRESSURE GRADIENT OVER THE INNER
CHANNELS BETWEEN HIGH OVER THE YUKON AND THE NEXT PACIFIC LOW.

MODELS STILL IN FAIR AGREEMENT FOR SYNOPTIC PATTERN THROUGH 84
HOURS. THE GEM HAS BEEN MOST CONSISTENT THE PAST FEW DAYS AND WAS
KEPT AS MAIN MODEL WITH A MIX OF SOME GFS. THIS BLEND WAS VERY
CLOSE TO INHERITED FORECAST SO LITTLE CHANGE RESULTED. FOR THE REST
OF THE EXTENDED RANGE FORECAST LEFT THE WPC ENSEMBLE BLEND. IN THESE
LATER PERIODS THE GFS HAS BEEN MORE CONSISTENT WHILE THE ECMWF
SHOWED SOME LARGE CHANGES WITH THE MOST RECENT RUN DROPPING THE
END OF WEEK LOW CENTER DOWN TO 957 MB, A 20 MB DIFFERENCE FROM THE
GFS. FORECAST CONFIDENCE IS ABOVE AVERAGE INITIALLY BUT DROPS
RAPIDLY BY MID WEEK.


&&

.AJK WATCHES/WARNINGS/ADVISORIES...
PUBLIC...NONE.
MARINE...GALE WARNING FOR PKZ052.
         SMALL CRAFT ADVISORY FOR PKZ043-051.
         SMALL CRAFT ADVISORY DUE TO SEAS FOR PKZ041-042.

&&

$$

EAL/PRB

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








000
FXAK68 PAFC 291326 AAA
AFDAFC

SOUTHCENTRAL AND SOUTHWEST ALASKA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE ANCHORAGE AK
526 AM AKDT MON SEP 29 2014

.ANALYSIS AND UPPER LEVELS...LARGE SCALE SPLIT FLOW PERSISTS OVER
THE ALASKA REGION. A VERTICALLY STACKED LOW SOUTH OF THE CENTRAL
ALEUTIANS IS THE SHORT-TERM FEATURE IN THE SOUTHERN
STREAM...PRODUCING SCATTERED SHOWERS AND GUSTY WINDS OVER THE
CENTRAL ALEUTIANS AS IT CONTINUES TO TRACK SOUTHEASTWARD. THE MAIN
FOCUS FOR THE SHORT-TERM FORECAST IS THE NORTHERN STREAM TROUGH
CURRENTLY MOVING THROUGH WESTERN ALASKA. CURRENT WATER VAPOR
IMAGERY SHOWS THIS STRONG TROUGH RAPIDLY DIGGING THROUGH THE
WESTERN MAINLAND AND EDGING INTO THE WESTERN PORTION OF
SOUTHCENTRAL...BEING THE MAIN WEATHER PRODUCER OVER THE NEXT 36
HOURS FOR SOUTHCENTRAL ALASKA.

&&

.MODEL DISCUSSION...MODELS REMAIN IN GOOD SYNOPTIC AGREEMENT AND
FORECAST CONFIDENCE IS GENERALLY HIGH. THERE ARE SOME MINOR
DIFFERENCES IN THE POSITIONING AND PROGRESSION OF THE UPPER LOW
FORMING OVER THE NORTHERN GULF TONIGHT...WITH THE NAM BEING A
SLIGHT OUTLIER WITH A FASTER EASTWARD MOVEMENT OF THE AMPLIFYING
UPPER TROUGH. CONFIDENCE CONTINUES TO INCREASE THAT THE NEW
SURFACE LOW WILL DEVELOP NEAR CAPE SUCKLING THIS AFTERNOON AND
QUICKLY FOLLOW THE UPPER LOW OFF TO THE EAST. PRESSURE GRADIENTS
WILL QUICKLY TIGHTEN ALONG THE NORTH GULF COAST AS THIS LOW
DEVELOPS...COINCIDING WITH THE ARRIVAL OF COLD DENSE AIR FROM
INTERIOR ALASKA.

MEANWHILE...THE REMNANTS OF A TROPICAL SYSTEM CURRENTLY EAST OF
JAPAN ARE STILL EXPECTED TO GET ABSORBED BY THE LARGE VERTICALLY
STACKED LOW SOUTH OF THE ALEUTIANS BY TUESDAY NIGHT. NOT
SURPRISINGLY THE MODELS CONTINUE TO STRUGGLE WITH THE EXACT
DETAILS OF THIS INFUSION OF MOISTURE AND ENERGY...BUT FORTUNATELY
THE ENTIRE COMPLEX WILL REMAIN LARGELY SOUTH OF THE FORECAST AREA.
A BROAD-BRUSHED SOLUTION OF THE GFS AND ECMWF GLOBAL SOLUTIONS IS
PREFERRED.

&&

.SHORT TERM FORECAST...

SOUTHCENTRAL ALASKA...WINDS WILL BEGIN TO PICK UP OVER MUCH OF
SOUTHCENTRAL TODAY AS THE ARCTIC TROUGH DROPS SOUTHEASTWARD
THROUGH THE AREA...WITH THE HIGHEST WINDS THROUGH AND NEAR
MOUNTAIN GAPS. AS IS TYPICALLY THE CASE THE STRONGEST WINDS BY FAR
WILL BE ALONG PRINCE WILLIAM SOUND AND THE NORTH GULF COAST. WHILE
WINDS WILL BE VERY STRONG FOR THIS EARLY IN THE
SEASON...CONDITIONS ARE STILL EXPECTED TO REMAIN BELOW WARNING
LEVELS.

CLOUDS WILL DEVELOP LATER THIS MORNING AS STRONG DYNAMIC LIFT
ASSOCIATED WITH THE TROUGH ENTERS THE AREA...BUT BEST CHANCES FOR
PRECIPITATION TO ACTUALLY REACH THE GROUND REMAIN LARGELY FROM THE
MATANUSKA VALLEY NORTHWARD. FURTHER EAST...AS THE SURFACE LOW
BEGINS TO FORM AND PUMP MOISTURE OVER THE COASTAL MOUNTAINS...MORE
WIDESPREAD PRECIPITATION WILL DEVELOP THIS AFTERNOON. PRECIP WILL
NOT LAST OVERLY LONG AS THE BEST LIFT QUICKLY RACES EASTWARD
TONIGHT. HOWEVER...WHAT DOES FALL WILL BE IN THE FORM OF SNOW AT
HIGHER ELEVATIONS OVER THE EASTERN COPPER RIVER BASIN WITH SOME
ACCUMULATIONS LIKELY. AS THE UPPER LEVEL TROUGH EXITS TO THE EAST
TOMORROW AFTERNOON...WINDS WILL BEGIN TO DIMINISH AS THE PRESSURE
GRADIENT QUICKLY LOOSENS UP OVER THE AREA. HIGH PRESSURE WILL THEN
BEGIN TO BUILD IN FROM THE WEST...BRINGING CLEAR AND DRY
CONDITIONS BACK TO THE REGION BY MIDWEEK.

SOUTHWEST ALASKA...A FEW SHOWERS ALONG THE BASE OF THE UPPER LEVEL
TROUGH ARE EXPECTED TO LAST THROUGHOUT THE DAY AND TAPER OFF
TONIGHT...AS THE UPPER TROUGH TRACKS FURTHER EAST. HIGH PRESSURE
WILL RAPIDLY BUILD IN BEHIND THIS TROUGH MONDAY AND PROVIDE DRY
AND SEASONABLY COOL TEMPERATURES THROUGH MUCH OF THE WEEK.

BERING SEA/ALEUTIANS...RAIN AND WIND WILL HOLD ON ALONG THE
CENTRAL ALEUTIANS UNTIL THE LOW TO THE SOUTH FINALLY DROPS
FURTHER INTO THE PACIFIC LATER TONIGHT. OTHERWISE HIGH PRESSURE
WILL BUILD OVER THE CENTRAL BERING SEA AND CONTINUE TO STRENGTHEN
THROUGH MID WEEK...SETTING UP A BLOCKING PATTERN AND PROVIDING
VERY QUIET CONDITIONS FOR MOST OF THE REGION. THE ONE EXCEPTION
WILL BE THE WESTERN ALEUTIANS ON THE UPSTREAM SIDE OF THE RIDGE
WHICH WILL SEE IMPACTS FROM A SYSTEM PASSING TO THE WEST MID WEEK.

&&

.LONG TERM FORECAST (THU OCT 2ND - SUN OCT 5)...

ON THURSDAY...A CLOSED BLOCKING HIGH OVER THE BERING WITH A RIDGE
AXIS EXTENDING INTO EASTERN SIBERIA WILL FORCE A CROSS POLAR FLOW
PATTERN TO DEVELOP...WITH A STRENGTHENING ARCTIC TROUGH DEVELOPING
OVER THE MAINLAND. DISTURBANCES IN NORTH TO NORTHWEST FLOW WILL
TRACK INTO THE AREA...WITH PROGRESSIVELY COLDER AIR PUSHING INTO
THE REGION. 850 HPA TEMPERATURES (APPROXIMATELY 5000 FEET) WILL
BE APPROACHING -4 TO -8 CELSIUS BY SUNDAY...WHICH WILL EVENTUALLY
BRING THE COLDEST TEMPERATURES OF THE YEAR TO SOUTHERN ALASKA.
SOME UNCERTAINTY DEVELOPS LATE FRIDAY AND SATURDAY WITH THE
DEVELOPMENT OF A COLD UPPER LEVEL VORTEX OVER SOUTHERN ALASKA AND
THE NORTHERN GULF...WITH THE ECMWF AND CANADIAN GDPS MUCH MORE
BULLISH WITH THE SCENARIO THAN THE PROGRESSIVE GFS. SUCH A
SOLUTION WOULD INCREASE SNOW CHANCES...ESPECIALLY ACROSS THE
COPPER BASIN. THE FORECAST WILL TAKE A MIDDLE GROUND APPROACH AND
WILL CONTINUE TO MENTION SNOW CHANCES ACROSS PORTIONS OF
SOUTHCENTRAL BY THE WEEKEND.


&&

.AFC WATCHES/WARNINGS/ADVISORIES...
PUBLIC...NONE.
MARINE...GALE WARNING...119 121 127 129 130 131 174 176 177.
FIRE WEATHER...NONE.

&&

$$

TP SEP 14



000
FXAK68 PAFC 291326 AAA
AFDAFC

SOUTHCENTRAL AND SOUTHWEST ALASKA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE ANCHORAGE AK
526 AM AKDT MON SEP 29 2014

.ANALYSIS AND UPPER LEVELS...LARGE SCALE SPLIT FLOW PERSISTS OVER
THE ALASKA REGION. A VERTICALLY STACKED LOW SOUTH OF THE CENTRAL
ALEUTIANS IS THE SHORT-TERM FEATURE IN THE SOUTHERN
STREAM...PRODUCING SCATTERED SHOWERS AND GUSTY WINDS OVER THE
CENTRAL ALEUTIANS AS IT CONTINUES TO TRACK SOUTHEASTWARD. THE MAIN
FOCUS FOR THE SHORT-TERM FORECAST IS THE NORTHERN STREAM TROUGH
CURRENTLY MOVING THROUGH WESTERN ALASKA. CURRENT WATER VAPOR
IMAGERY SHOWS THIS STRONG TROUGH RAPIDLY DIGGING THROUGH THE
WESTERN MAINLAND AND EDGING INTO THE WESTERN PORTION OF
SOUTHCENTRAL...BEING THE MAIN WEATHER PRODUCER OVER THE NEXT 36
HOURS FOR SOUTHCENTRAL ALASKA.

&&

.MODEL DISCUSSION...MODELS REMAIN IN GOOD SYNOPTIC AGREEMENT AND
FORECAST CONFIDENCE IS GENERALLY HIGH. THERE ARE SOME MINOR
DIFFERENCES IN THE POSITIONING AND PROGRESSION OF THE UPPER LOW
FORMING OVER THE NORTHERN GULF TONIGHT...WITH THE NAM BEING A
SLIGHT OUTLIER WITH A FASTER EASTWARD MOVEMENT OF THE AMPLIFYING
UPPER TROUGH. CONFIDENCE CONTINUES TO INCREASE THAT THE NEW
SURFACE LOW WILL DEVELOP NEAR CAPE SUCKLING THIS AFTERNOON AND
QUICKLY FOLLOW THE UPPER LOW OFF TO THE EAST. PRESSURE GRADIENTS
WILL QUICKLY TIGHTEN ALONG THE NORTH GULF COAST AS THIS LOW
DEVELOPS...COINCIDING WITH THE ARRIVAL OF COLD DENSE AIR FROM
INTERIOR ALASKA.

MEANWHILE...THE REMNANTS OF A TROPICAL SYSTEM CURRENTLY EAST OF
JAPAN ARE STILL EXPECTED TO GET ABSORBED BY THE LARGE VERTICALLY
STACKED LOW SOUTH OF THE ALEUTIANS BY TUESDAY NIGHT. NOT
SURPRISINGLY THE MODELS CONTINUE TO STRUGGLE WITH THE EXACT
DETAILS OF THIS INFUSION OF MOISTURE AND ENERGY...BUT FORTUNATELY
THE ENTIRE COMPLEX WILL REMAIN LARGELY SOUTH OF THE FORECAST AREA.
A BROAD-BRUSHED SOLUTION OF THE GFS AND ECMWF GLOBAL SOLUTIONS IS
PREFERRED.

&&

.SHORT TERM FORECAST...

SOUTHCENTRAL ALASKA...WINDS WILL BEGIN TO PICK UP OVER MUCH OF
SOUTHCENTRAL TODAY AS THE ARCTIC TROUGH DROPS SOUTHEASTWARD
THROUGH THE AREA...WITH THE HIGHEST WINDS THROUGH AND NEAR
MOUNTAIN GAPS. AS IS TYPICALLY THE CASE THE STRONGEST WINDS BY FAR
WILL BE ALONG PRINCE WILLIAM SOUND AND THE NORTH GULF COAST. WHILE
WINDS WILL BE VERY STRONG FOR THIS EARLY IN THE
SEASON...CONDITIONS ARE STILL EXPECTED TO REMAIN BELOW WARNING
LEVELS.

CLOUDS WILL DEVELOP LATER THIS MORNING AS STRONG DYNAMIC LIFT
ASSOCIATED WITH THE TROUGH ENTERS THE AREA...BUT BEST CHANCES FOR
PRECIPITATION TO ACTUALLY REACH THE GROUND REMAIN LARGELY FROM THE
MATANUSKA VALLEY NORTHWARD. FURTHER EAST...AS THE SURFACE LOW
BEGINS TO FORM AND PUMP MOISTURE OVER THE COASTAL MOUNTAINS...MORE
WIDESPREAD PRECIPITATION WILL DEVELOP THIS AFTERNOON. PRECIP WILL
NOT LAST OVERLY LONG AS THE BEST LIFT QUICKLY RACES EASTWARD
TONIGHT. HOWEVER...WHAT DOES FALL WILL BE IN THE FORM OF SNOW AT
HIGHER ELEVATIONS OVER THE EASTERN COPPER RIVER BASIN WITH SOME
ACCUMULATIONS LIKELY. AS THE UPPER LEVEL TROUGH EXITS TO THE EAST
TOMORROW AFTERNOON...WINDS WILL BEGIN TO DIMINISH AS THE PRESSURE
GRADIENT QUICKLY LOOSENS UP OVER THE AREA. HIGH PRESSURE WILL THEN
BEGIN TO BUILD IN FROM THE WEST...BRINGING CLEAR AND DRY
CONDITIONS BACK TO THE REGION BY MIDWEEK.

SOUTHWEST ALASKA...A FEW SHOWERS ALONG THE BASE OF THE UPPER LEVEL
TROUGH ARE EXPECTED TO LAST THROUGHOUT THE DAY AND TAPER OFF
TONIGHT...AS THE UPPER TROUGH TRACKS FURTHER EAST. HIGH PRESSURE
WILL RAPIDLY BUILD IN BEHIND THIS TROUGH MONDAY AND PROVIDE DRY
AND SEASONABLY COOL TEMPERATURES THROUGH MUCH OF THE WEEK.

BERING SEA/ALEUTIANS...RAIN AND WIND WILL HOLD ON ALONG THE
CENTRAL ALEUTIANS UNTIL THE LOW TO THE SOUTH FINALLY DROPS
FURTHER INTO THE PACIFIC LATER TONIGHT. OTHERWISE HIGH PRESSURE
WILL BUILD OVER THE CENTRAL BERING SEA AND CONTINUE TO STRENGTHEN
THROUGH MID WEEK...SETTING UP A BLOCKING PATTERN AND PROVIDING
VERY QUIET CONDITIONS FOR MOST OF THE REGION. THE ONE EXCEPTION
WILL BE THE WESTERN ALEUTIANS ON THE UPSTREAM SIDE OF THE RIDGE
WHICH WILL SEE IMPACTS FROM A SYSTEM PASSING TO THE WEST MID WEEK.

&&

.LONG TERM FORECAST (THU OCT 2ND - SUN OCT 5)...

ON THURSDAY...A CLOSED BLOCKING HIGH OVER THE BERING WITH A RIDGE
AXIS EXTENDING INTO EASTERN SIBERIA WILL FORCE A CROSS POLAR FLOW
PATTERN TO DEVELOP...WITH A STRENGTHENING ARCTIC TROUGH DEVELOPING
OVER THE MAINLAND. DISTURBANCES IN NORTH TO NORTHWEST FLOW WILL
TRACK INTO THE AREA...WITH PROGRESSIVELY COLDER AIR PUSHING INTO
THE REGION. 850 HPA TEMPERATURES (APPROXIMATELY 5000 FEET) WILL
BE APPROACHING -4 TO -8 CELSIUS BY SUNDAY...WHICH WILL EVENTUALLY
BRING THE COLDEST TEMPERATURES OF THE YEAR TO SOUTHERN ALASKA.
SOME UNCERTAINTY DEVELOPS LATE FRIDAY AND SATURDAY WITH THE
DEVELOPMENT OF A COLD UPPER LEVEL VORTEX OVER SOUTHERN ALASKA AND
THE NORTHERN GULF...WITH THE ECMWF AND CANADIAN GDPS MUCH MORE
BULLISH WITH THE SCENARIO THAN THE PROGRESSIVE GFS. SUCH A
SOLUTION WOULD INCREASE SNOW CHANCES...ESPECIALLY ACROSS THE
COPPER BASIN. THE FORECAST WILL TAKE A MIDDLE GROUND APPROACH AND
WILL CONTINUE TO MENTION SNOW CHANCES ACROSS PORTIONS OF
SOUTHCENTRAL BY THE WEEKEND.


&&

.AFC WATCHES/WARNINGS/ADVISORIES...
PUBLIC...NONE.
MARINE...GALE WARNING...119 121 127 129 130 131 174 176 177.
FIRE WEATHER...NONE.

&&

$$

TP SEP 14




000
FXAK69 PAFG 291011
AFDAFG

NORTHERN ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE FAIRBANKS AK
211 AM AKDT MON SEP 29 2014

.DISCUSSION...
MODELS IN DECENT AGREEMENT THROUGH 48 HOURS. LONG WAVE TROUGH
PATTERN HAS ESTABLISHED OVER NORTHERN ALASKA AND WILL BE THE MAIN
FEATURE THROUGH TUE. UPPER LEVEL RIDGING BUILDS IN OVER
SOUTHWESTERN ALASKA AND THE BERING SEA ON TUE AND THEN CONTINUES
THROUGH WED NIGHT.

UPPER LEVEL RIDGING OVER THE BERING SEA WILL BECOMING A BLOCKING
RIDGE THROUGH LATE FRI. MEANWHILE A REINFORCING SHOT FROM ANOTHER
UPPER LOW IN THE HIGH ARCTIC WILL CRUSH THE RIDGE DOWN AND
ESTABLISH A DEEP TROUGH FROM THE POLE DOWN TO BELOW 45 DEGREES
NORTH BY THU.

IN THE SHORT TERM...UPPER LEVEL TROUGH THROUGH NORTHERN ALASKA.
THE COLD AIR BEHIND THIS FEATURE IS MORE OF AN UPPER LEVEL COLD
FRONT THAN A SURFACE COLD FRONT AT THIS TIME. IT IS ALSO
CAMOUFLAGED VERY WELL IN THE TEMPERATURE FIELD ALSO BECAUSE OF
THE CLOUD COVER ASSOCIATED WITH THE TROUGH. THIS CLOUD COVER IS
HOLDING THE SURFACE TEMPERATURES UP A BIT WHILE POINTS TO THE EAST
MAY BE COLDER BUT LACK OF CLOUD COVER IS THE CAUSE FOR THE
DISPARITY.

THE UPPER LEVEL LOW ABOUT 150 NM N OF POINT LAY WILL ADVANCE ITS
AGENDA THROUGH THE STATE AS ITS FRONT MOVES TO THE EAST. ITS
AGENDA APPEARS TO BE THAT OF COOLER TEMPERATURES ALOFT INITIALLY
BUT EVENTUALLY MIXING DOWN TO THE SURFACE LEVEL OVER THE NEXT 24
TO 36 HOURS AS WELL AS PROVIDING AMPLE OPPORTUNITY FOR RAIN AND
SNOW SHOWERS OVER NORTHERN ALASKA THROUGH THE WEEK.

WINDS ALONG THE WEST COAST WILL APPROACH GALE FROM KOTZEBUE
NORTHWARD TO POINT LAY THROUGH THIS EVENING BEFORE DIMINISHING AS
THE INITIAL COLD ADVECTION QUICKLY TURNS TO WARM ADVECTION MON
EVENING AND OVERNIGHT ON THE WEST COAST.

HIGH SURF OUT FOR ZONES 201 AND 207 SEEM LEGITIMATE AT THIS POINT
HOWEVER ZONE 202 HAS BECOME MORE UNLIKELY BUT WILL CONTINUE TO
MONITOR IT.

COASTAL HAZARD POTENTIAL DAYS 3 AND 4...NONE

&&

.HYDROLOGY...NONE.


&&

.AFG WATCHES/WARNINGS/ADVISORIES...
HIGH SURF ADVISORY FOR AKZ201-AKZ202-AKZ207.

SMALL CRAFT ADVISORY FOR PKZ210-PKZ215-PKZ230.

GALE WARNING FOR PKZ220-PKZ225-PKZ230.
&&

$$

CF SEP 14




000
FXAK69 PAFG 291011
AFDAFG

NORTHERN ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE FAIRBANKS AK
211 AM AKDT MON SEP 29 2014

.DISCUSSION...
MODELS IN DECENT AGREEMENT THROUGH 48 HOURS. LONG WAVE TROUGH
PATTERN HAS ESTABLISHED OVER NORTHERN ALASKA AND WILL BE THE MAIN
FEATURE THROUGH TUE. UPPER LEVEL RIDGING BUILDS IN OVER
SOUTHWESTERN ALASKA AND THE BERING SEA ON TUE AND THEN CONTINUES
THROUGH WED NIGHT.

UPPER LEVEL RIDGING OVER THE BERING SEA WILL BECOMING A BLOCKING
RIDGE THROUGH LATE FRI. MEANWHILE A REINFORCING SHOT FROM ANOTHER
UPPER LOW IN THE HIGH ARCTIC WILL CRUSH THE RIDGE DOWN AND
ESTABLISH A DEEP TROUGH FROM THE POLE DOWN TO BELOW 45 DEGREES
NORTH BY THU.

IN THE SHORT TERM...UPPER LEVEL TROUGH THROUGH NORTHERN ALASKA.
THE COLD AIR BEHIND THIS FEATURE IS MORE OF AN UPPER LEVEL COLD
FRONT THAN A SURFACE COLD FRONT AT THIS TIME. IT IS ALSO
CAMOUFLAGED VERY WELL IN THE TEMPERATURE FIELD ALSO BECAUSE OF
THE CLOUD COVER ASSOCIATED WITH THE TROUGH. THIS CLOUD COVER IS
HOLDING THE SURFACE TEMPERATURES UP A BIT WHILE POINTS TO THE EAST
MAY BE COLDER BUT LACK OF CLOUD COVER IS THE CAUSE FOR THE
DISPARITY.

THE UPPER LEVEL LOW ABOUT 150 NM N OF POINT LAY WILL ADVANCE ITS
AGENDA THROUGH THE STATE AS ITS FRONT MOVES TO THE EAST. ITS
AGENDA APPEARS TO BE THAT OF COOLER TEMPERATURES ALOFT INITIALLY
BUT EVENTUALLY MIXING DOWN TO THE SURFACE LEVEL OVER THE NEXT 24
TO 36 HOURS AS WELL AS PROVIDING AMPLE OPPORTUNITY FOR RAIN AND
SNOW SHOWERS OVER NORTHERN ALASKA THROUGH THE WEEK.

WINDS ALONG THE WEST COAST WILL APPROACH GALE FROM KOTZEBUE
NORTHWARD TO POINT LAY THROUGH THIS EVENING BEFORE DIMINISHING AS
THE INITIAL COLD ADVECTION QUICKLY TURNS TO WARM ADVECTION MON
EVENING AND OVERNIGHT ON THE WEST COAST.

HIGH SURF OUT FOR ZONES 201 AND 207 SEEM LEGITIMATE AT THIS POINT
HOWEVER ZONE 202 HAS BECOME MORE UNLIKELY BUT WILL CONTINUE TO
MONITOR IT.

COASTAL HAZARD POTENTIAL DAYS 3 AND 4...NONE

&&

.HYDROLOGY...NONE.


&&

.AFG WATCHES/WARNINGS/ADVISORIES...
HIGH SURF ADVISORY FOR AKZ201-AKZ202-AKZ207.

SMALL CRAFT ADVISORY FOR PKZ210-PKZ215-PKZ230.

GALE WARNING FOR PKZ220-PKZ225-PKZ230.
&&

$$

CF SEP 14



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