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000
FXAK69 PAFG 282206
AFDAFG

NORTHERN ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE FAIRBANKS AK
206 PM AKDT THU APR 28 2016

.DISCUSSION...

MODELS IN AGREEMENT WITH WEAK EAST SOUTHEAST FLOW ALOFT WITH
A SERIES OF WEAK SHORTWAVES MOVING ACROSS THE INTERIOR AND
WESTERN INTERIOR THROUGH SATURDAY. THESE SHORT WAVE TROUGHS WILL
PROVIDE SOME UPPER LIFT TO BOOST SHOWER ACTIVITY OVER THE CENTRAL
AND WESTERN INTERIORS.

SURFACE...
BROAD HIGH PRESSURE WILL REMAIN OVER THE ARCTIC THROUGH FRIDAY.
WEAK TROUGHING WILL PERSIST OVER THE ARCTIC COAST AND WESTERN
ARCTIC THROUGH FRI. A 987 MB LOW OVER THE CENTRAL ALEUTIANS WILL
MOVE EAST AND WEAKEN TO 992 MB BY FRIDAY MORNING. AN INVERTED
TROUGH WILL REMAIN OVER THE BERING STRAIT THROUGH FRIDAY. WEAK
LOW PRESSURE WILL PERSIST OVER THE WESTERN AND CENTRAL INTERIORS.

ALONG THE ARCTIC COAST... EAST TO NORTHEAST WINDS MAINLY 10-15
MPH WILL CONTINUE THROUGH FRIDAY ALONG WITH THE LOW STRATIFORM
CLOUD REGIME AND AREAS OF FLURRIES AND FOG.

INTERIOR AND WESTERN INTERIOR...
SCATTERED RAIN SHOWERS ARE EXPECTED OVER MOST AREAS SOUTH OF THE
BROOKS RANGE THIS AFTERNOON THROUGH SATURDAY. THIS AFTERNOON
THROUGH SATURDAY THE MOST ACTIVE CONVECTION WILL BE OVER THE
NORTHERN AND WESTERN INTERIOR WITH SURFACE CAPE TO 150-250 J/KG
AND SURFACE-500 MB LIFTED INDEX AS LOW AS -2.


HYDRO...AN ICE JAM IS LOCATED 10 MILES DOWNRIVER FROM EAGLE AND IS
CAUSING WATER AND ICE TO BACK UP INTO THE COMMUNITY. THE
YUKON RIVER IS BANKFULL AND FLOWING OVERBANK IN SOME LOCATIONS.
RESIDENTS HAVE REPORTED RISING WATER LEVELS AND MINOR FLOODING IN
THE COMMUNITY. THE ROAD BETWEEN EAGLE AND EAGLE VILLAGE IS
INUNDATED AND THERE IS WATER IN YARDS OF HOMES ALONG THE LOWER
RIVER BANKS. WATER LEVELS WILL REMAIN HIGH OR CONTINUE TO SLOWLY
RISE UNTIL THE ICE JAM RELEASES.

FIRE WEATHER...
AFTERNOON HUMIDITIES OVER SOUTHERN INTERIOR AREAS ARE EXPECTED
TO BE A LITTLE HIGHER THIS AFTERNOON DUE TO YESTERDAYS SHOWERS.
SOME DRYING IS EXPECTED IN SOUTHERN INTERIOR AREAS TODAY. IN
ALASKA RANGE PASSES...SOUTH WINDS 15 TO 25 MPH GUSTING TO 35 MPH
THIS AFTERNOON AND EVENING.


&&

.AFG WATCHES/WARNINGS/ADVISORIES...
SMALL CRAFT ADVISORY FOR PKZ210.

BRISK WIND ADVISORY FOR PKZ220-PKZ225.
&&

$$

APR 16





000
FXAK69 PAFG 281206
AFDAFG

NORTHERN ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE FAIRBANKS AK
406 AM AKDT THU APR 28 2016

.DISCUSSION...
THE HIGH PRESSURE CENTER THAT HAS BEEN SO PERSISTENT OVER
OR NORTH OF OUR ARCTIC OFFSHORE WATERS SO FAR THIS YEAR IS
PRESENTLY CENTERED NEAR PRINCE PATRICK ISLAND IN THE CANADIAN
ARCHIPELAGO. THE GFS AND ECMF MODELS KEEP IT NEARLY STATIONARY
FOR THE NEXT COUPLE OF DAYS...AND THEN HAVE IT RETREATING
NORTHWESTWARD AS WEAK SOUTHERLY FLOW ALOFT DEVELOPS OVER THE
SOUTHERN BEAUFORT SEA. IN THE SHORT TERM...A WEAK TROUGH IS
EXPECTED TO PERSIST IN THE VICINITY OF THE ARCTIC COAST FROM
ABOUT CAPE HALKETT EAST...SOMETIMES JUST NORTH OF THE COAST AND
SOMETIMES JUST SOUTH OF IT...AND WINDS ON THE ARCTIC COAST ARE
EXPECTED TO REMAIN LIGHT TO MODERATE IN CONSEQUENCE. FOR
COMPARISON...THEY ARE 20 TO 30 MPH IN OFFSHORE AREA 510.

LIGHT SOUTHEAST TO EAST FLOW ALOFT WILL PERSIST OVER NORTHERN
ALASKA SOUTH OF THE BROOKS RANGE. A SERIES OF SHORT WAVES
MOVING UP FROM THE GULF OF ALASKA WILL TRIGGER MAINLY AFTERNOON
AND EVENING SHOWERS. LOW LEVEL MOISTURE IS LIMITED...AND THE
ATMOSPHERE TENDS TO STABILIZE SOMEWHAT IN BETWEEN THE SHORT
WAVES...SO THERE WILL BE LITTLE SHOWER ACTIVITY THAT IS NOT
TRIGGERED BY THEM. THE SHORT WAVE THAT PROVIDED 221 THROUGH
224 AND THE SOUTHERN HALF OF ZONE 220 WITH THE SHOWERS ON
WEDNESDAY IS MOVING NORTH AND WEST. EXPECT SUMMERY CONVECTIVE
SHOWERS IN ZONES 215...216...218...219...AND NORTHERN/WESTERN
PORTIONS OF ZONES 220 AND 221 TODAY. THUNDERSTORMS IF ANY WILL BE
VERY ISOLATED. NO CONVECTION TODAY IN THE SOUTHEAST INTERIOR
EXCEPT MAYBE NEAR THE NORTHERN BORDER OF 222. SHOWERS POSSIBLE
TODAY IN EASTERN PORTIONS OF ZONES 212...210...AND 217.

THE NEXT SHORT WAVE WILL PROVIDE SOME SHOWERS IN THE SOUTHEAST
INTERIOR ON FRIDAY...WHILE THE FIRST ONE GENERATES SOME ON
THE SEWARD PENINSULA.

&&

.FIRE WEATHER...
THE AIRMASS THAT HAS MOVED IN BEHIND WEDNESDAYS`S CONVECTIVE
ACTION IS SOMEWHAT WARMER AND DRYER. EXPECT MINIMUM RH IN THE
20S TO THE MID 30S IN THE SOUTHEAST INTERIOR TODAY. THE THERMAL
TROUGH WILL REFORM OVER THE TANANA VALLEY...WITH GUSTY SOUTH
WINDS THROUGH ALASKA RANGE PASSES AGAIN TODAY.

&&

.AFG WATCHES/WARNINGS/ADVISORIES...
SMALL CRAFT ADVISORY FOR PKZ210-PKZ220.
&&

$$

DJH APR 16





000
FXAK69 PAFG 272256
AFDAFG

NORTHERN ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE FAIRBANKS AK
256 PM AKDT WED APR 27 2016

.DISCUSSION...


MODELS IN AGREEMENT WITH WEAK EAST SOUTHEAST FLOW ALOFT WITH
A SERIES OF WEAK SHORTWAVES MOVING ACROSS THE INTERIOR AND
WESTERN INTERIOR THROUGH FRIDAY. THESE SHORT WAVE TROUGHS WILL
PROVIDE SOME UPPER LIFT TO BOOST SHOWER ACTIVITY OVER THE
INTERIOR.

SURFACE...
BROAD HIGH PRESSURE WILL REMAIN OVER THE ARCTIC THROUGH FRIDAY.
WEAK TROUGHING WILL PERSIST OVER THE ARCTIC COAST AND WESTERN
ARCTIC THROUGH FRI. A 975 MB LOW NEAR ATKA WILL MOVE EAST
AND WEAKEN TO 992 MB BY THURSDAY EVENING. AN INVERTED TROUGH WILL
REMAIN OVER THE BERING STRAIT THROUGH FRIDAY.

ALONG THE ARCTIC COAST... EAST TO NORTHEAST WINDS MAINLY 10-15
MPH WILL CONTINUE THROUGH FRIDAY ALONG WITH THE LOW STRATIFORM
CLOUD REGIME AND AREAS OF FLURRIES AND FOG. PATCHY FREEZING
DRIZZLE MAY OCCUR AT TIMES IN SOME AREAS.

INTERIOR...
SCATTERED RAIN SHOWERS ARE EXPECTED OVER MOST AREAS SOUTH OF THE
BROOKS RANGE TODAY THROUGH FRIDAY. CONVECTION WILL BE MAINLY
SHALLOW THIS AFTERNOON WITH LOW TOP SHOWERS AND NO THUNDERSTORMS
EXPECTED. ON THURSDAY THE MOST ACTIVE CONVECTION WILL BE OVER THE
NORTHERN AND WESTERN INTERIOR WITH SURFACE CAPE TO 100-200 J/KG
AND SURFACE-500 MB LIFTED INDEX AS LOW AS -2.

WEST COAST...
TODAY...ISOLATED AFTERNOON/EARLY EVENING SHOWERS POSSIBLE OVER
EASTERN INLAND AREAS SOUTH AND EAST OF NORTON SOUND. THURSDAY
AND FRIDAY...ISOLATED TO SCATTERED SHOWERS OVER EASTERN INLAND
AREAS SOUTH AND EAST OF NORTON SOUND...AND ALSO EXTREME EASTERN
INLAND AREAS ON THE SEWARD PENINSULA.

HYDRO...AN ICE JAM IS LOCATED 10 MILES DOWNRIVER FROM EAGLE AND IS
CAUSING WATER AND ICE TO BACK UP INTO THE COMMUNITY. THE
YUKON RIVER IS BANKFULL AND FLOWING OVERBANK IN SOME LOCATIONS.
RESIDENTS HAVE REPORTED RISING WATER LEVELS AND MINOR FLOODING IN
THE COMMUNITY. WATER LEVELS WILL REMAIN HIGH OR CONTINUE TO SLOWLY
RISE UNTIL THE ICE JAM RELEASES.

FIRE WEATHER...
AFTERNOON HUMIDITIES OVER SOUTHERN INTERIOR AREAS ARE EXPECTED
TO BE A LITTLE HIGHER THIS AFTERNOON DUE TO MORE WIDESPREAD CLOUD
COVER AND SHOWER ACTIVITY WHICH SHOULD TRIM DOWN SURFACE
TEMPERATURES BY A FEW DEGREES. SOME DRYING IS EXPECTED IN SOUTHERN
INTERIOR AREAS ON THURSDAY. GUSTY WINDS AROUND SHOWERS THIS
AFTERNOON IN ZONE 223. IN ALASKA RANGE PASSES...SOUTH WINDS 15 TO
25 MPH GUSTING TO 35 MPH THIS AFTERNOON AND EVENING.

AFG WATCHES/WARNINGS/ADVISORIES...
SMALL CRAFT ADVISORY FOR PKZ210-PKZ220.

BRISK WIND ADVISORY FOR PKZ245.

$$


&&

.AFG WATCHES/WARNINGS/ADVISORIES...
SMALL CRAFT ADVISORY FOR PKZ210-PKZ220.
&&

$$

JK APR 16





000
FXAK69 PAFG 271341
AFDAFG

NORTHERN ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE FAIRBANKS AK
541 AM AKDT WED APR 27 2016

.DISCUSSION...

UPPER AIR...
A LIGHT MAINLY EAST TO SOUTHEAST WIND FLOW PATTERN ALOFT WILL
CONTINUE OVER NORTHERN ALASKA THROUGH SATURDAY. A WEAK SHORT WAVE
TROUGH NOW MOVING ACROSS THE NORTHEASTERN INTERIOR WILL DAMPEN OUT
OVER THE CENTRAL AND EASTERN BROOKS RANGE THIS AFTERNOON. ANOTHER
WEAK SHORT WAVE TROUGH WILL MOVE ONSHORE ALONG THE NORTH GULF
COAST THIS EVENING...THEN SWING NORTHWESTWARD TO THE ALASKA WEST
AND BROOKS RANGE BY FRIDAY MORNING. A THIRD WEAK SHORT WAVE TROUGH
WILL MOVE ONSHORE ALONG THE NORTH GULF COAST FRIDAY AFTERNOON AND
MOVE SLOWLY NORTHWARD INTO THE INTERIOR FRIDAY NIGHT INTO
SATURDAY. THESE SHORT WAVE TROUGHS WILL PROVIDE SOME UPPER LIFT
TO BOOST SHOWER ACTIVITY OVER THE INTERIOR.

SURFACE...
A 1034 MB HIGH CENTERED 600 MILES NORTH OF THE MACKENZIE RIVER
DELTA WILL MOVE TO NEAR MELVILLE AND PRINCE PATRICK ISLANDS BY
FRIDAY AFTERNOON. A THERMAL TROUGH EXTENDING FROM ANVIK TO NEAR
FAIRBANKS TO NEAR NORTHWAY WILL REMAIN NEARLY STATIONARY TODAY
AND DRIFT SLOWLY NORTHWARD WHILE GRADUALLY WEAKENING TONIGHT.
A THERMAL TROUGH WILL REDEVELOP ALONG THE ALASKA RANGE THURSDAY
NIGHT AND MOVE NORTHWARD TO A LINE ST MARYS-GALENA-FAIRBANKS-50
MILES SOUTH OF EAGLE BY FRIDAY MORNING.

ALONG THE ARCTIC COAST... EAST TO NORTHEAST WINDS MAINLY 10-15
MPH WILL CONTINUE THROUGH FRIDAY ALONG WITH THE LOW STRATIFORM
CLOUD REGIME AND AREAS OF FLURRIES AND FOG. PATCHY FREEZING
DRIZZLE MAY OCCUR AT TIMES IN SOME AREAS.

INTERIOR...
ISOLATED TO SCATTERED SHOWERS ARE EXPECTED OVER MOST AREAS SOUTH
OF THE BROOKS RANGE TODAY THROUGH FRIDAY. CONVECTION WILL BE
MAINLY SHALLOW TODAY WITH LOW TOP SHOWERS AND NO THUNDERSTORMS
EXPECTED. ON THURSDAY THE MOST ACTIVE CONVECTION WILL BE OVER THE
NORTHERN AND WESTERN INTERIOR WITH SURFACE CAPE TO 100-200 J/KG
AND SURFACE-500 MB LIFTED INDEX AS LOW AS -2. ISOLATED THUNDERSTORMS
ARE EXPECTED IN THIS AREA OF GREATER INSTABILITY. ON FRIDAY...
ISOLATED THUNDERSTORMS POSSIBLE IN THE NORTHERN PARTS OF THE
WESTERN INTERIOR AND NORTHEAST INTERIOR WITH POCKETS OF 100+ J/KG
OF SURFACE CAPE AND SURFACE-500 MB LIFTED INDEX TO -2.

WEST COAST...
TODAY...ISOLATED AFTERNOON/EARLY EVENING SHOWERS POSSIBLE OVER
EASTERN INLAND AREAS SOUTH AND EAST OF NORTON SOUND. THURSDAY
AND FRIDAY...ISOLATED TO SCATTERED SHOWERS OVER EASTERN INLAND
AREAS SOUTH AND EAST OF NORTON SOUND...AND ALSO EXTREME EASTERN
INLAND AREAS ON THE SEWARD PENINSULA.

OUTLOOK SATURDAY THROUGH MONDAY...
WARM PATTERN IS EXPECTED TO CONTINUE WITH ABOVE NORMAL
TEMPERATURES OVER THE NORTHERN ALASKA MAINLAND. GFS LIFTED
INDEX/CAPE PROGS INDICATE GOOD POTENTIAL FOR A SHOWERY REGIME
OVER MOST OF THE INTERIOR AND IN INLAND WEST COAST AREAS...WITH
THE MOST ACTIVE AREAS BEING IN THE NORTHERN AND WESTERN INTERIOR
WHERE ISOLATED THUNDERSTORMS WILL BE POSSIBLE IN ADDITION TO THE
SHOWERS.

THE CURRENT NCEP ENSEMBLE MEAN TEMPERATURE ANOMALY FORECAST FOR
WEEKS 1 AND 2 INDICATES TEMPERATURES AVERAGING 3 TO 6 DEGREES
CELSIUS ABOVE NORMAL OVER MUCH OF THE NORTHERN ALASKA MAINLAND.

&&

.FIRE WEATHER...
AFTERNOON HUMIDITIES OVER SOUTHERN INTERIOR AREAS ARE EXPECTED
TO BE A LITTLE HIGHER THAN YESTERDAY DUE TO MORE WIDESPREAD CLOUD
COVER AND SHOWER ACTIVITY WHICH SHOULD TRIM DOWN SURFACE
TEMPERATURES BY A FEW DEGREES. SOME DRYING IS EXPECTED IN
SOUTHERN INTERIOR AREAS THURSDAY AND FRIDAY. MINIMUM RH TODAY
MAINLY 28-43 PERCENT IN MOST SOUTHERN INTERIOR AREAS...LOWERING TO
AROUND 22-37 PERCENT THURSDAY AND FRIDAY. IN ALASKA RANGE
PASSES...SOUTH WINDS 15-25 MPH WITH LOCAL GUSTS TO 35 MPH EXPECTED
TODAY AND TONIGHT DIMINISHING THURSDAY BUT REDEVELOPING LATE
THURSDAY NIGHT. SEE MAIN DISCUSSION FOR SHOWERS/THUNDERSTORMS.

&&

.AFG WATCHES/WARNINGS/ADVISORIES...
SMALL CRAFT ADVISORY FOR PKZ210-PKZ220.

BRISK WIND ADVISORY FOR PKZ245.
&&

$$

RF APR 16





000
FXAK69 PAFG 262057
AFDAFG

NORTHERN ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE FAIRBANKS AK
1257 PM AKDT TUE APR 26 2016

.DISCUSSION...

MODELS...VERY GOOD AGREEMENT IN THE FIRST 72 HOURS AND MAINTAINS
REASONABLE AGREEMENT THROUGH 144 HOURS. JUST NOT SEEING A LOT OF
CHANGES AT THE SURFACE AS MODELS MAINTAIN THE CYCLONIC FLOW OVER
THE STATE WITH LEESIDE TROUGHING NORTH OF THE ALASKA RANGE AND
OVER THE ARCTIC COAST. THERMAL LOW ENHANCES THE LEESIDE TROUGH
DURING THE DAY AND WEAKENS OVERNIGHT. WILL USE AN EQUAL BLEND FOR
THE SHORT TERM FORECASTS...BUT MAKE ONLY MINOR ADJUSTMENTS TO THE
TEMPERATURE FORECASTS THAT HAVE BEEN ADJUSTED TO BE A FEW DEGREES
ABOVE NORMAL ALREADY. AS FAR AS PRECIPITATION THE GFS AND ECMWF
ARE WAY OVERDOING THE COVERAGE...SO WILL USE MAINLY THE AKNAMDNG5
WITH SOME MINOR POST EDITING TO ADD A LITTLE MORE COVERAGE. NOT
MUCH SHOWING UP FOR CONVECTIVE POTENTIAL UNTIL AT LEAST FRIDAY.
THERE ARE INDICATIONS OF POTENTIAL FOR SHOWERY ACTIVITY THOUGH.

ALOFT...AT 500 HPA...RIDGING OVER THE BROOKS RANGE IS SLOWLY
SLIDING NORTH AND WILL BE OVER THE ARCTIC COAST EARLY THURSDAY
MORNING. AN ELONGATED LOW PRESSURE SYSTEM WITH SEVERAL LOW REMAINS
OVER THE ALEUTIANS AND SOUTH OF THE GULF OF ALASKA. A 521 DAM LOW
400 NM SOUTH OF HOMER AND A 518 DAM LOW OVER COLD BAY WILL WEAKEN
AND BE ABSORBED INTO THE 508 DAM LOW THAT WILL BE 200 NM SOUTH OF
ATKA EARLY WEDNESDAY MORNING WITH A TROUGH EXTENDING FROM THE
SOUTHCENTRAL BERING SEA EAST OVER KODIAK ISLAND THEN SOUTHEAST.
THE LOW WILL CONTINUE SLOWLY EAST TO BE 50 NM SOUTH OF NIKOLSKI BY
WEDNESDAY EVENING WITH THE TROUGH MOVING NORTH TO LIE FROM THE
PRIBILOFS TO ANCHORAGE TO WATSON LAKE YUKON...THEN BY THURSDAY
MORNING THE LOW WILL BE 100 NM SOUTH OF DUTCH HARBOR WITH THE
TROUGH LYING FROM CAPE NEWENHAM TO FAIRBANKS TO FORT MCPHERSON
YUKON BY THURSDAY MORNING AS IT CONTINUE TO ROTATE TO THE
NORTHWEST PUSHING THE RIDGING JUST OFFSHORE. AT 850 HPA...SLIGHT
COOLING ACROSS THE INTERIOR THROUGH WEDNESDAY WILL BRING THE
TEMPERATURES BELOW ZERO CELSIUS...THEN THEY WARM BACK UP TO AROUND
THE ZERO MARK FOR THE REMAINDER OF THE WEEK.

SURFACE...SAME GENERAL PATTERN OF THE PAST COUPLE WEEKS HOLDS
THROUGH THIS WEEK WITH WEAK CYCLONIC FLOW OVER THE STATE AND
LEESIDE...THERMAL TROUGH NORTH OF THE ALASKA RANGE AND WEAK
TROUGHING OVER THE ARCTIC COAST...AS WELL AS AN INVERTED TROUGH
OVER THE WEST COAST. DECAYING FRONTS MOVING NORTH OUT OF THE GULF
WILL ENHANCE THE CHANCE FOR SHOWERS THROUGH THE WEEK...BUT NOT
SEEING ANYTHING SIGNIFICANT UNTIL THE WEEKEND WHEN WE COULD SEE
SOME THUNDERSTORM ACTIVITY.

ARCTIC COAST AND BROOKS RANGE...JUST NOT SEEING ANYTHING TO CHANGE
FROM CONTINUITY. STRATUS ON THE 26/1601Z SPORT NPP VIIRS
NIGHTTIME MICROPHYSICS IMAGE APPEARS TO BE PRETTY MUCH IN THE SAME
PLACE IT WAS ON MONDAY AND NO REASON FOR IT TO CHANGE IN THE SHORT
TERM. NORTHEAST TO EAST FLOW CONTINUES ALONG THE COAST WITH WINDS
10 TO 20 MPH FOR MOST AREAS. WINDS IN THE BROOKS RANGE AND OVER
THE FLATS ARE LIGHTER. EXPECT A FEW FLURRIES WITH THE
STRATUS...BUT NO SIGNIFICANT ACCUMULATION. CLEAR TO PARTLY CLOUDY
CONDITIONS WILL CONTINUE IN THE BROOKS RANGE.

WEST COAST AND WESTERN INTERIOR...INVERTED TROUGH REMAINS OVER THE
COAST...THIS DOES PROVIDE FOR A CHANCE OF SHOWERS OVER THE
AREA...BUT THEY WILL BE LIGHT. THE DECAYING FRONT MOVING OVER THE
LOWER YUKON DELTA WILL ALSO PROVIDE A CHANCE OF SCATTERED LIGHT
RAINSHOWERS. WILL BE MIXED WITH SNOW DURING THE OVERNIGHT HOURS AS
TEMPERATURES WILL CONTINUE TO COOL BELOW FREEZING OVERNIGHT IN
MANY AREAS. WINDS MAINLY NORTHEAST AT 5 TO 15 MPH...THE EXCEPTION
OF COURSE IS ST LAWRENCE ISLAND AND THE BERING STRAIT COAST WHICH
WILL HAVE WINDS IN THE 30 TO 40 MPH RANGE AS RIDGING OVER CHUKOTKA
TIGHTENS THE GRADIENT UP OVER THE AREA.

CENTRAL AND EASTERN INTERIOR...JUST A SLIGHT CHANCE OF ISOLATED
SHOWERS AROUND FAIRBANKS THIS AFTERNOON...MAINLY OVER THE HILLS.
FOR THE REMAINDER OF THE AREA SLIGHT CHANCE OVER THE FORTYMILE
COUNTRY AS WELL AS SOUTH OF FORT YUKON AND IN THE WHITE MOUNTAINS.
ALSO A SLIGHT CHANCE OF THUNDERSTORMS IN THE WHITE MOUNTAINS AND
FORTYMILE COUNTRY. CHANCE OF SHOWERS IN THE SAME AREAS
WEDNESDAY...THEN MOST OF THE SHOWER ACTIVITY WILL SHIFT TO THE
NORTH WITH THE UPPER LEVEL TROUGH ON THURSDAY. SLIGHTLY COOLER
TEMPERATURES THE NEXT COUPLE DAYS...BUT STILL AT OR ABOVE NORMAL.
SOME PATCHY FOG IN THE EARLY MORNING HOURS AROUND AREAS WHERE THE
WATER IS OPENING UP. NORTHEAST TO EAST WINDS WILL CONTINUE FOR
MOST AREAS AT 5 TO 15 MPH...EXCEPT IN THE ALASKA RANGE WHERE WINDS
WILL BE SOUTH IN THE AFTERNOONS GUSTING TO AROUND 25 MPH AS THE
THERMAL LOW STRENGTHENS.

&&

.FIRE WEATHER...JUST SLIGHT CHANCES OF THUNDERSTORM ACTIVITY UNTIL
THE WEEKEND. MODELS HAVE NOT BEEN VERY GOOD WITH THE EARLY SEASON
CONVECTIVE NUMBERS SO NOT PUTTING A LOT OF WEIGHT IN THEM.
SLIGHTLY COOLER AND THERE IS A BETTER CHANCE OF SOME SCATTERED
SHOWERS WITH THE DECAYING FRONT AND UPPER LEVEL SHORTWAVE MOVING
THROUGH THE AREA. TEMPERATURES A LITTLE COOLER AND DEWPOINTS RISE
A BIT THE NEXT COUPLE DAYS. GREENUP IN THE TANANA VALLEY WAS
RECORDED BY THE FAIRBANKS OFFICE TODAY.

&&

.AFG WATCHES/WARNINGS/ADVISORIES...

GALE WARNING FOR ZONES PKZ210-PKZ220.

BRISK WIND ADVISORY FOR PKZ240-PKZ245.

&&

$$

SDB APR 16





000
FXAK69 PAFG 262057
AFDAFG

NORTHERN ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE FAIRBANKS AK
1257 PM AKDT TUE APR 26 2016

.DISCUSSION...

MODELS...VERY GOOD AGREEMENT IN THE FIRST 72 HOURS AND MAINTAINS
REASONABLE AGREEMENT THROUGH 144 HOURS. JUST NOT SEEING A LOT OF
CHANGES AT THE SURFACE AS MODELS MAINTAIN THE CYCLONIC FLOW OVER
THE STATE WITH LEESIDE TROUGHING NORTH OF THE ALASKA RANGE AND
OVER THE ARCTIC COAST. THERMAL LOW ENHANCES THE LEESIDE TROUGH
DURING THE DAY AND WEAKENS OVERNIGHT. WILL USE AN EQUAL BLEND FOR
THE SHORT TERM FORECASTS...BUT MAKE ONLY MINOR ADJUSTMENTS TO THE
TEMPERATURE FORECASTS THAT HAVE BEEN ADJUSTED TO BE A FEW DEGREES
ABOVE NORMAL ALREADY. AS FAR AS PRECIPITATION THE GFS AND ECMWF
ARE WAY OVERDOING THE COVERAGE...SO WILL USE MAINLY THE AKNAMDNG5
WITH SOME MINOR POST EDITING TO ADD A LITTLE MORE COVERAGE. NOT
MUCH SHOWING UP FOR CONVECTIVE POTENTIAL UNTIL AT LEAST FRIDAY.
THERE ARE INDICATIONS OF POTENTIAL FOR SHOWERY ACTIVITY THOUGH.

ALOFT...AT 500 HPA...RIDGING OVER THE BROOKS RANGE IS SLOWLY
SLIDING NORTH AND WILL BE OVER THE ARCTIC COAST EARLY THURSDAY
MORNING. AN ELONGATED LOW PRESSURE SYSTEM WITH SEVERAL LOW REMAINS
OVER THE ALEUTIANS AND SOUTH OF THE GULF OF ALASKA. A 521 DAM LOW
400 NM SOUTH OF HOMER AND A 518 DAM LOW OVER COLD BAY WILL WEAKEN
AND BE ABSORBED INTO THE 508 DAM LOW THAT WILL BE 200 NM SOUTH OF
ATKA EARLY WEDNESDAY MORNING WITH A TROUGH EXTENDING FROM THE
SOUTHCENTRAL BERING SEA EAST OVER KODIAK ISLAND THEN SOUTHEAST.
THE LOW WILL CONTINUE SLOWLY EAST TO BE 50 NM SOUTH OF NIKOLSKI BY
WEDNESDAY EVENING WITH THE TROUGH MOVING NORTH TO LIE FROM THE
PRIBILOFS TO ANCHORAGE TO WATSON LAKE YUKON...THEN BY THURSDAY
MORNING THE LOW WILL BE 100 NM SOUTH OF DUTCH HARBOR WITH THE
TROUGH LYING FROM CAPE NEWENHAM TO FAIRBANKS TO FORT MCPHERSON
YUKON BY THURSDAY MORNING AS IT CONTINUE TO ROTATE TO THE
NORTHWEST PUSHING THE RIDGING JUST OFFSHORE. AT 850 HPA...SLIGHT
COOLING ACROSS THE INTERIOR THROUGH WEDNESDAY WILL BRING THE
TEMPERATURES BELOW ZERO CELSIUS...THEN THEY WARM BACK UP TO AROUND
THE ZERO MARK FOR THE REMAINDER OF THE WEEK.

SURFACE...SAME GENERAL PATTERN OF THE PAST COUPLE WEEKS HOLDS
THROUGH THIS WEEK WITH WEAK CYCLONIC FLOW OVER THE STATE AND
LEESIDE...THERMAL TROUGH NORTH OF THE ALASKA RANGE AND WEAK
TROUGHING OVER THE ARCTIC COAST...AS WELL AS AN INVERTED TROUGH
OVER THE WEST COAST. DECAYING FRONTS MOVING NORTH OUT OF THE GULF
WILL ENHANCE THE CHANCE FOR SHOWERS THROUGH THE WEEK...BUT NOT
SEEING ANYTHING SIGNIFICANT UNTIL THE WEEKEND WHEN WE COULD SEE
SOME THUNDERSTORM ACTIVITY.

ARCTIC COAST AND BROOKS RANGE...JUST NOT SEEING ANYTHING TO CHANGE
FROM CONTINUITY. STRATUS ON THE 26/1601Z SPORT NPP VIIRS
NIGHTTIME MICROPHYSICS IMAGE APPEARS TO BE PRETTY MUCH IN THE SAME
PLACE IT WAS ON MONDAY AND NO REASON FOR IT TO CHANGE IN THE SHORT
TERM. NORTHEAST TO EAST FLOW CONTINUES ALONG THE COAST WITH WINDS
10 TO 20 MPH FOR MOST AREAS. WINDS IN THE BROOKS RANGE AND OVER
THE FLATS ARE LIGHTER. EXPECT A FEW FLURRIES WITH THE
STRATUS...BUT NO SIGNIFICANT ACCUMULATION. CLEAR TO PARTLY CLOUDY
CONDITIONS WILL CONTINUE IN THE BROOKS RANGE.

WEST COAST AND WESTERN INTERIOR...INVERTED TROUGH REMAINS OVER THE
COAST...THIS DOES PROVIDE FOR A CHANCE OF SHOWERS OVER THE
AREA...BUT THEY WILL BE LIGHT. THE DECAYING FRONT MOVING OVER THE
LOWER YUKON DELTA WILL ALSO PROVIDE A CHANCE OF SCATTERED LIGHT
RAINSHOWERS. WILL BE MIXED WITH SNOW DURING THE OVERNIGHT HOURS AS
TEMPERATURES WILL CONTINUE TO COOL BELOW FREEZING OVERNIGHT IN
MANY AREAS. WINDS MAINLY NORTHEAST AT 5 TO 15 MPH...THE EXCEPTION
OF COURSE IS ST LAWRENCE ISLAND AND THE BERING STRAIT COAST WHICH
WILL HAVE WINDS IN THE 30 TO 40 MPH RANGE AS RIDGING OVER CHUKOTKA
TIGHTENS THE GRADIENT UP OVER THE AREA.

CENTRAL AND EASTERN INTERIOR...JUST A SLIGHT CHANCE OF ISOLATED
SHOWERS AROUND FAIRBANKS THIS AFTERNOON...MAINLY OVER THE HILLS.
FOR THE REMAINDER OF THE AREA SLIGHT CHANCE OVER THE FORTYMILE
COUNTRY AS WELL AS SOUTH OF FORT YUKON AND IN THE WHITE MOUNTAINS.
ALSO A SLIGHT CHANCE OF THUNDERSTORMS IN THE WHITE MOUNTAINS AND
FORTYMILE COUNTRY. CHANCE OF SHOWERS IN THE SAME AREAS
WEDNESDAY...THEN MOST OF THE SHOWER ACTIVITY WILL SHIFT TO THE
NORTH WITH THE UPPER LEVEL TROUGH ON THURSDAY. SLIGHTLY COOLER
TEMPERATURES THE NEXT COUPLE DAYS...BUT STILL AT OR ABOVE NORMAL.
SOME PATCHY FOG IN THE EARLY MORNING HOURS AROUND AREAS WHERE THE
WATER IS OPENING UP. NORTHEAST TO EAST WINDS WILL CONTINUE FOR
MOST AREAS AT 5 TO 15 MPH...EXCEPT IN THE ALASKA RANGE WHERE WINDS
WILL BE SOUTH IN THE AFTERNOONS GUSTING TO AROUND 25 MPH AS THE
THERMAL LOW STRENGTHENS.

&&

.FIRE WEATHER...JUST SLIGHT CHANCES OF THUNDERSTORM ACTIVITY UNTIL
THE WEEKEND. MODELS HAVE NOT BEEN VERY GOOD WITH THE EARLY SEASON
CONVECTIVE NUMBERS SO NOT PUTTING A LOT OF WEIGHT IN THEM.
SLIGHTLY COOLER AND THERE IS A BETTER CHANCE OF SOME SCATTERED
SHOWERS WITH THE DECAYING FRONT AND UPPER LEVEL SHORTWAVE MOVING
THROUGH THE AREA. TEMPERATURES A LITTLE COOLER AND DEWPOINTS RISE
A BIT THE NEXT COUPLE DAYS. GREENUP IN THE TANANA VALLEY WAS
RECORDED BY THE FAIRBANKS OFFICE TODAY.

&&

.AFG WATCHES/WARNINGS/ADVISORIES...

GALE WARNING FOR ZONES PKZ210-PKZ220.

BRISK WIND ADVISORY FOR PKZ240-PKZ245.

&&

$$

SDB APR 16





000
FXAK69 PAFG 261317
AFDAFG

NORTHERN ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE FAIRBANKS AK
517 AM AKDT TUE APR 26 2016

.DISCUSSION...

UPPER AIR...
A WEAK UPPER LEVEL RIDGE CURRENTLY EXTENDS FROM THE BERING
STRAIT TO OLD CROW AND SOUTHEASTWARD. THE RIDGE WILL SHIFT SLOWLY
NORTHEASTWARD THROUGH WEDNESDAY NIGHT. RIDGE AXIS LATE WEDNESDAY
NIGHT WILL EXTEND FROM THE EASTERN BEAUFORT SEA TO THE MACKENZIE
RIVER DELTA AND SOUTHWESTWARD. OVER THE INTERIOR AND SOUTHERN
WEST COAST AREAS...AN EASTERLY FLOW PATTERN WILL BECOME MAINLY
SOUTHEASTERLY BY THURSDAY NIGHT. SEVERAL VERY WEAK RIPPLES WILL
MOVE NORTHWESTWARD ACROSS THE INTERIOR THROUGH WEDNESDAY. A
SOMEWHAT STRONGER SHORT WAVE WILL MOVE NORTHWARD TO THE GULF
COAST BY WEDNESDAY AFTERNOON...THEN SWING NORTHWESTWARD TO THE
WEST COAST BY FRIDAY MORNING. CURRENT MODEL RUNS ARE IN GENERALLY
GOOD AGREEMENT THROUGH FRIDAY.

SURFACE...
THE THERMAL TROUGH THAT WAS NORTH OF THE ALASKA RANGE YESTERDAY
HAS WEAKENED CONSIDERABLY...BUT IS EXPECTED TO BEGIN TO STRENGTHEN
AGAIN THIS EVENING...THEN WEAKEN SOME WEDNESDAY. THIS SHOULD
RESULT IN GUSTY SOUTH WINDS REDEVELOPING IN ALASKA RANGE PASSES
THIS EVENING AND CONTINUING OVERNIGHT BEFORE WEAKENING SOME
WEDNESDAY. WIND GUSTS ARE EXPECTED TO REMAIN BELOW ADVISORY
LEVELS. A WEAK THERMAL IS EXPECTED TO PERSIST NORTH OF THE ALASKA
RANGE THROUGH FRIDAY NIGHT AND THIS SHOULD ALLOW A CONTINUATION OF
SOUTHERLY WINDS THROUGH ALASKA RANGE PASSES. OVER THE ARCTIC
REGION...A 1037 MB HIGH CENTERED ABOUT 600 MILES NORTH OF THE
MACKENZIE RIVER DELTA WILL REMAIN NEARLY STATIONARY AND WEAKEN TO
1032 MB BY LATE WEDNESDAY NIGHT. EAST TO NORTHEAST WINDS WILL
CONTINUE ALONG THE ARCTIC COAST...WITH LOW STRATIFORM CLOUD COVER
AND AREAS OF FLURRIES AND FOG PERSISTING.

CONVECTIVE ACTIVITY...

THIS AFTERNOON AND EVENING...ISOLATED TO SCATTERED SHOWERS
EXPECTED OVER THE SOUTHERN INTERIOR AND ALSO INTERIOR WEST COAST
AREAS SOUTH AND EAST OF NORTON SOUND. THERE IS A REMOTE
POSSIBILITY OF THUNDERSTORMS IN SOUTHERN ZONE 215...BUT NOT
WORTH MENTION IN THE FORECAST.

WEDNESDAY AFTERNOON AND EVENING...ISOLATED TO SCATTERED SHOWERS
ARE EXPECTED OVER MOST INTERIOR AREAS SOUTH OF THE BROOKS RANGE.
SHOWERS WILL ALSO BE POSSIBLE OVER THE EASTERN INLAND AREAS OF
ZONES 212 AND 214. THE GREATEST INSTABILITY IS EXPECTED TO BE OVER
NORTHERN ZONE 220 AND EASTERN ZONE 226...WITH SURFACE-500 MB
LIFTED INDEXES TO -2 AND SURFACE CAPES OF AROUND 200 J/KG.
ISOLATED THUNDERSTORMS ARE EXPECTED IN THAT AREAS OF INSTABILITY.

THURSDAY AFTERNOON AND EVENING...
ISOLATED TO SCATTERED SHOWERS ARE EXPECTED OVER MOST INTERIOR
AREAS NORTH AND WEST OF THE ALASKA RANGE. ISOLATED THUNDERSTORMS
EXPECTED IN ZONES 216 AND 219 WITH SURFACE-500 MB LIFTED INDEXES
TO -2 AND SURFACE CAPES TO AROUND 200 J/KG.

MEDIUM RANGE OUTLOOK...
A MAINLY SOUTH TO SOUTHEAST FLOW PATTERN ALOFT WITH ABOVE NORMAL
SURFACE TEMPERATURES IS EXPECTED TO CONTINUE IN DAYS 4-7. AN
UNSTABLE AIR MASS AND A SHOWERY REGIME WILL PERSIST OVER MUCH OF
THE INTERIOR AND IN INLAND WEST COAST AREAS SOUTH AND EAST OF
NORTON SOUND. ISOLATED THUNDERSTORMS WILL BE POSSIBLE OVER MUCH OF
THE NORTHERN AND WESTERN INTERIOR FRIDAY THROUGH SUNDAY...AND OVER
MUCH`OF THE WESTERN INTERIOR MONDAY. THE LATEST RUN OF THE NCEP
COUPLED FORECAST SYSTEM MODEL INDICATES ENSEMBLE MEAN TEMPERATURE
ANOMALIES OF +3 TO +6 DEGREES CELSIUS OVER ALMOST OF NORTHERN
ALASKA FOR WEEKS 1 AND 2.

&&

.FIRE WEATHER...
MINIMUM RH OF 25-40 PERCENT EXPECTED IN MOST OF THE SOUTHERN
INTERIOR ZONES TODAY...AND 28-43 PERCENT WEDNESDAY. SOUTH WINDS
15-25 MPH ARE EXPECTED IN ALASKA RANGE PASSES TONIGHT THROUGH
WEDNESDAY NIGHT...WITH LOCAL GUSTS TO 40 MPH IN ZONE 225 PASSES.
SEE MAIN DISCUSSION FOR THUNDERSTORMS.

&&

.AFG WATCHES/WARNINGS/ADVISORIES...
BRISK WIND ADVISORY FOR PKZ210-PKZ220-PKZ245.
&&

$$

RF APR 16





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