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000
FXAK68 PAFC 270112
AFDAFC

SOUTHCENTRAL AND SOUTHWEST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE ANCHORAGE AK
412 PM AKST MON JAN 26 2015

.ANALYSIS AND UPPER LEVELS...
UPPER LEVELS...
A TROUGH EXTENDED FROM A CLOSED LOW OVER THE ARCTIC OCEAN SOUTH
AND WEST ACROSS THE CENTRAL INTERIOR. A WEAK HIGH PRESSURE RIDGE
WAS EVIDENT ACROSS THE GULF WITH A LOW COMPLEX OVER THE ALEUTIANS
AND EASTERN BERING SEA. WATER VAPOR IMAGERY SHOWED CIRRUS CLOUDS
BEING ENTRAINED IN THE WESTERLY FLOW AND SPREADING ACROSS THE
SOUTHERN MAINLAND.

SURFACE...
HIGH PRESSURE CONTINUED COLD TEMPERATURES ACROSS THE
MAINLAND. COLD AMBIENT TEMPERATURES COMBINED WITH GUSTY WINDS
PRODUCED WIDE SPREAD WIND CHILLS OF 40 TO 50 BELOW ACROSS THE
DELTA. LOCAL WIND CHILLS OF AROUND 40 BELOW WERE OBSERVED WITH
BRISK GAP FLOWS IN THOMPSON PASS.

AN 988 MB LOW CENTER WAS EVIDENT NORTH OF UNALASKA WITH THE
TRAILING OCCLUDED FRONT EXTENDING ACROSS THE AK PEN TO JUST WEST
OF KODIAK ISLAND. SNOW WAS EVIDENT IN ADVANCE OF THE THIS FRONT
OVER BRISTOL BAY AND EXTENDED EAST TO NEAR KODIAK. RAIN SHOWERS
WERE OBSERVED SOUTH OF THE FRONT OVER THE AK PEN. BRISK WINDS IN
ADVANCE OF THE FRONT WILL COMBINE WITH SNOWFALL TO PRODUCE
BLOWING SNOW ACROSS BRISTOL BAY THROUGH TONIGHT.

&&

.MODEL DISCUSSION...
THE 12Z ECMWF/GFS MODEL RUNS ARE IN GOOD AGREEMENT AND REASONABLE.
THE 12Z NAM WAS THE OUTLIER...HOWEVER THE 18Z NAM HAS COME INTO
AGREEMENT WITH THE HEMISPHERIC MODELS.

&&

.SHORT TERM FORECAST SOUTHCENTRAL ALASKA (DAYS 1 AND 2)...

TRICKY LOW TEMPERATURE FORECASTS IN STORE THE NEXT COUPLE OF
NIGHTS/MORNINGS AS HIGH LEVEL CLOUDS AND PATCHY FOG FORMATION WILL
BE THE MAIN DETERMINANTS AS TO HOW COLD IT GETS. FOR NOW...DECIDED
TO GO WITH A SLIGHTLY WARMER TO MIDDLE-OF-THE-ROAD FORECAST FOR
MOST AREAS...BUT ANY BRIEF CLEARING AND/OR DECOUPLING OF WINDS IN
EXPOSED AREAS WILL RESULT IN A RAPID PLUNGE OF SEVERAL DEGREES.

AS FOR PRECIPITATION...FLURRIES WILL BE POSSIBLE WITH FOG
FORMATION AROUND ANCHORAGE AND THE COPPER RIVER BASIN TONIGHT AND
ALSO AGAIN TUESDAY EVENING. A WEAK DISTURBANCE NEAR THE NORTH GULF
COAST WILL BRING SOME LIGHT SNOW SHOWERS TO EASTERN PRINCE WILLIAM
SOUND THROUGH TONIGHT.

KODIAK AND THE SOUTHERN KENAI PENINSULA WILL BEGIN TO EXPERIENCE
INCREASING PROBABILITIES OF PRECIPITATION OVER THE NEXT COUPLE OF
DAYS AS EASTERLY FLOW INCREASES AHEAD OF A WEATHER FRONT THAT WILL
MOVE NORTH TOWARD THE AREA. KODIAK WILL CONTINUE TO SEE PERIODS OF
LIGHT SNOW BUT WILL GRADUALLY MIX WITH AND THEN CHANGE TO RAIN AS
WARMER AIR MOVES NORTH WITH THE APPROACHING WEATHER FRONT.

&&

.SHORT TERM FORECAST SOUTHWEST ALASKA (TONIGHT THROUGH THURSDAY NIGHT)...

WIND CHILLS REMAIN A SIGNIFICANT CONCERN ACROSS THE KUSKOKWIM
DELTA THIS EVENING AS WIND CHILLS HAVE REMAINED IN THE 35 BELOW TO
45 BELOW THRESHOLD THROUGH THE MAJORITY OF THE DAY. HOWEVER...THERE
IS SOME GOOD NEWS AS TEMPERATURES ARE EXPECTED TO GRADUALLY WARM
OVERNIGHT...WHICH SHOULD LEAD TO WIND CHILL VALUES IN THE RANGE OF
15 TO 30 BELOW COME TUESDAY MORNING. OVERNIGHT WIND CHILLS WILL
REMAIN A CONCERN ACROSS THE KUSKOKWIM DELTA AS NORTHEASTERLY WINDS
AT THE SURFACE CONTINUE TO USHER IN THE BITTERLY COLD CONTINENTAL
ARCTIC AIR MASS THAT HAS BUILT OVER THE INTERIOR. THE LOWER KUSKOKWIM
VALLEY WILL ALSO CONTINUE TO SEE SOME BITTERLY COLD WEATHER BUT
LUCKILY HAVE LIGHT WINDS WHICH IS PREVENTING WIND CHILLS FROM
BECOMING AN ISSUE. TEMPERATURES ACROSS THE LOWER KUSKOKWIM VALLEY
WILL GRADUALLY WARM THROUGH THE REMAINDER OF THE WEEK...ALTHOUGH
TEMPERATURES ARE STILL NO EXPECTED TO WARM ABOVE ZERO.

OVER THE BRISTOL BAY AREA...A WINTER WEATHER ADVISORY FOR SNOW AND
BLOWING SNOW HAS BEEN ISSUED AS RADAR REFLECTIVITIES ARE ALREADY
SHOWING DECENT SNOW MOVING FROM SOUTH TO NORTH. AREAS NORTH AND
WEST OF KING SALMON (INCLUDING DILLINGHAM AND KOLIGANEK) WILL SEE
ANYWHERE FROM 5 TO 8 INCHES OF SNOW ACCUMULATION WHILE THE
REMAINDER OF THE ZONE WILL BE ON THE DRY SIDE...LARGELY FROM
DOWNSLOPING AS A WARM FRONT PUSHES NORTH. HOWEVER A FEW ISOLATED
SNOW SHOWERS NEAR KING SALMON CANNOT BE RULED OUT. STRONG WINDS
WILL ACCOMPANY THE SNOWFALL NORTH AND WEST OF KING SALMON WHICH
WILL ALLOW BLOWING SNOW CONDITIONS TO DEVELOP THAT WILL REDUCE
VISIBILITIES TO ONE HALF MILE OR LESS AT TIMES THROUGH TUESDAY
MORNING. AS SNOW TAPERS OFF TUESDAY MORNING...SKIES WILL
GRADUALLY CLEAR THROUGH THE REMAINDER OF THE WEEK WITH A BRIEF
WARM UP OBSERVED TUESDAY AND WEDNESDAY.

&&

.SHORT TERM FORECAST BERING SEA/ALEUTIANS (TONIGHT THROUGH THURSDAY
NIGHT)...

A BROAD COMPLEX LOW WILL CONTINUE TO SKIRT JUST SOUTH OF THE
ALEUTIAN ISLANDS THROUGH WEDNESDAY AFTERNOON BEFORE TAKING A
SOUTHERN TURN INTO THE NORTH PACIFIC AS A STRONG RIDGE OF HIGH
PRESSURE BEGINS TO SITUATE ITSELF ACROSS THE BERING SEA. A WARM
FRONT ASSOCIATED WITH THE COMPLEX LOW HAS MOVED NORTH OF THE
ALEUTIAN ISLANDS AND HAS STALLED JUST SOUTH OF THE PRIBILOF
ISLANDS. THIS IS EVIDENT IN THE SURFACE TEMPERATURE TRENDS OVER
THE PAST 24 HOURS. THE PRIBILOF ISLANDS ARE IN A "SWEET SPOT" AS
THEY CONTINUE TO SEE COLD NORTHEASTERLY FLOW AS PRECIPITATION WITH
THE DECAYING WARM FRONT SHIFTS NORTH. THIS WILL ALLOW THE PERIOD
OF SNOW THAT HAS BEEN OBSERVED THROUGHOUT THE DAY TO CONTINUE.
WITH THE BUILDING HIGH PRESSURE OVER THE WESTERN BERING...A STRONG
PRESSURE GRADIENT HAS DEVELOPED AND CREATED GUSTY WINDS ACROSS THE
PRIBILOF ISLANDS LEADING TO BLOWING SNOW CONDITIONS. THE CORE OF
THE STRONGEST WINDS WILL SHIFT WESTWARD TUESDAY AFTERNOON AND
BRING STRONG WINDS TO THE CENTRAL ALEUTIANS TUESDAY AFTERNOON
THROUGH THE REMAINDER OF THE WEEK.

&&

.LONG TERM FORECAST (DAYS 3 THROUGH 7)...
A WEAKENING FRONT/INVERTED TROUGH WILL BRING PRECIPITATION TO
KODIAK ISLAND AND AREAS ALONG THE NORTH GULF COAST TOWARDS THE
END OF THE WEEK...BUT OTHERWISE MUCH OF THE SOUTHERN MAINLAND WILL
REMAIN IN A DRY OFFSHORE FLOW PATTERN THROUGH FRIDAY AS A STOUT
UPPER RIDGE BUILDS OVER THE WESTERN BERING AND TEMPERATURES SLOWLY
MODERATE TO NEAR NORMAL VALUES.

FORECAST CONFIDENCE BEGINS TO DIMINISH THIS WEEKEND INTO NEXT WEEK
AS THE UPPER RIDGE MIGRATES EASTWARD AND EVOLVES INTO A CLOSED
UPPER HIGH OVER THE EASTERN BERING/WESTERN MAINLAND. WHERE THIS
FEATURE ULTIMATELY SETS UP WILL HAVE A LARGE IMPACT ON THE
NORTHWARD PROGRESSION OF A NORTH PACIFIC LOW MOVING TOWARDS THE
SOUTHERN GULF...AND THUS HAVE A LARGE IMPACT ON PRECIPITATION
CHANCES OVER THE MAINLAND. AT THIS POINT IT APPEARS THAT ANY
PRECIP WILL REMAIN FAR ENOUGH SOUTH TO MAINLY IMPACT AREAS FROM
THE ALASKA PENINSULA TO THE GULF COAST...WITH MUCH OF THE MAINLAND
AND BERING SEA REMAINING DRY AS PERSISTENT OFFSHORE FLOW KEEPS
GUSTY WINDS ALONG THE NORTH GULF COAST.

&&


.AFC WATCHES/WARNINGS/ADVISORIES...
PUBLIC...WIND CHILL ADVISORY 155. SNOW/BLOWING SNOW ADVISORY 161
         BLOWING SNOW ADVISORY 195.
MARINE...GALE WARNING 120 127 130 131 132 138 139 150 155 165 170
            172 173 175 176 177 179 185.
         HEAVY FRZ SPRAY 121 126 127 128 130 139 140 141 185.
FIRE WEATHER...NONE.

&&

$$

SYNOPSIS AND MODEL DISCUSSION...BC
SOUTHCENTRAL ALASKA...CC
SOUTHWEST ALASKA/BERING SEA/ALEUTIANS...MC
LONG TERM...CB




000
FXAK68 PAFC 270112
AFDAFC

SOUTHCENTRAL AND SOUTHWEST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE ANCHORAGE AK
412 PM AKST MON JAN 26 2015

.ANALYSIS AND UPPER LEVELS...
UPPER LEVELS...
A TROUGH EXTENDED FROM A CLOSED LOW OVER THE ARCTIC OCEAN SOUTH
AND WEST ACROSS THE CENTRAL INTERIOR. A WEAK HIGH PRESSURE RIDGE
WAS EVIDENT ACROSS THE GULF WITH A LOW COMPLEX OVER THE ALEUTIANS
AND EASTERN BERING SEA. WATER VAPOR IMAGERY SHOWED CIRRUS CLOUDS
BEING ENTRAINED IN THE WESTERLY FLOW AND SPREADING ACROSS THE
SOUTHERN MAINLAND.

SURFACE...
HIGH PRESSURE CONTINUED COLD TEMPERATURES ACROSS THE
MAINLAND. COLD AMBIENT TEMPERATURES COMBINED WITH GUSTY WINDS
PRODUCED WIDE SPREAD WIND CHILLS OF 40 TO 50 BELOW ACROSS THE
DELTA. LOCAL WIND CHILLS OF AROUND 40 BELOW WERE OBSERVED WITH
BRISK GAP FLOWS IN THOMPSON PASS.

AN 988 MB LOW CENTER WAS EVIDENT NORTH OF UNALASKA WITH THE
TRAILING OCCLUDED FRONT EXTENDING ACROSS THE AK PEN TO JUST WEST
OF KODIAK ISLAND. SNOW WAS EVIDENT IN ADVANCE OF THE THIS FRONT
OVER BRISTOL BAY AND EXTENDED EAST TO NEAR KODIAK. RAIN SHOWERS
WERE OBSERVED SOUTH OF THE FRONT OVER THE AK PEN. BRISK WINDS IN
ADVANCE OF THE FRONT WILL COMBINE WITH SNOWFALL TO PRODUCE
BLOWING SNOW ACROSS BRISTOL BAY THROUGH TONIGHT.

&&

.MODEL DISCUSSION...
THE 12Z ECMWF/GFS MODEL RUNS ARE IN GOOD AGREEMENT AND REASONABLE.
THE 12Z NAM WAS THE OUTLIER...HOWEVER THE 18Z NAM HAS COME INTO
AGREEMENT WITH THE HEMISPHERIC MODELS.

&&

.SHORT TERM FORECAST SOUTHCENTRAL ALASKA (DAYS 1 AND 2)...

TRICKY LOW TEMPERATURE FORECASTS IN STORE THE NEXT COUPLE OF
NIGHTS/MORNINGS AS HIGH LEVEL CLOUDS AND PATCHY FOG FORMATION WILL
BE THE MAIN DETERMINANTS AS TO HOW COLD IT GETS. FOR NOW...DECIDED
TO GO WITH A SLIGHTLY WARMER TO MIDDLE-OF-THE-ROAD FORECAST FOR
MOST AREAS...BUT ANY BRIEF CLEARING AND/OR DECOUPLING OF WINDS IN
EXPOSED AREAS WILL RESULT IN A RAPID PLUNGE OF SEVERAL DEGREES.

AS FOR PRECIPITATION...FLURRIES WILL BE POSSIBLE WITH FOG
FORMATION AROUND ANCHORAGE AND THE COPPER RIVER BASIN TONIGHT AND
ALSO AGAIN TUESDAY EVENING. A WEAK DISTURBANCE NEAR THE NORTH GULF
COAST WILL BRING SOME LIGHT SNOW SHOWERS TO EASTERN PRINCE WILLIAM
SOUND THROUGH TONIGHT.

KODIAK AND THE SOUTHERN KENAI PENINSULA WILL BEGIN TO EXPERIENCE
INCREASING PROBABILITIES OF PRECIPITATION OVER THE NEXT COUPLE OF
DAYS AS EASTERLY FLOW INCREASES AHEAD OF A WEATHER FRONT THAT WILL
MOVE NORTH TOWARD THE AREA. KODIAK WILL CONTINUE TO SEE PERIODS OF
LIGHT SNOW BUT WILL GRADUALLY MIX WITH AND THEN CHANGE TO RAIN AS
WARMER AIR MOVES NORTH WITH THE APPROACHING WEATHER FRONT.

&&

.SHORT TERM FORECAST SOUTHWEST ALASKA (TONIGHT THROUGH THURSDAY NIGHT)...

WIND CHILLS REMAIN A SIGNIFICANT CONCERN ACROSS THE KUSKOKWIM
DELTA THIS EVENING AS WIND CHILLS HAVE REMAINED IN THE 35 BELOW TO
45 BELOW THRESHOLD THROUGH THE MAJORITY OF THE DAY. HOWEVER...THERE
IS SOME GOOD NEWS AS TEMPERATURES ARE EXPECTED TO GRADUALLY WARM
OVERNIGHT...WHICH SHOULD LEAD TO WIND CHILL VALUES IN THE RANGE OF
15 TO 30 BELOW COME TUESDAY MORNING. OVERNIGHT WIND CHILLS WILL
REMAIN A CONCERN ACROSS THE KUSKOKWIM DELTA AS NORTHEASTERLY WINDS
AT THE SURFACE CONTINUE TO USHER IN THE BITTERLY COLD CONTINENTAL
ARCTIC AIR MASS THAT HAS BUILT OVER THE INTERIOR. THE LOWER KUSKOKWIM
VALLEY WILL ALSO CONTINUE TO SEE SOME BITTERLY COLD WEATHER BUT
LUCKILY HAVE LIGHT WINDS WHICH IS PREVENTING WIND CHILLS FROM
BECOMING AN ISSUE. TEMPERATURES ACROSS THE LOWER KUSKOKWIM VALLEY
WILL GRADUALLY WARM THROUGH THE REMAINDER OF THE WEEK...ALTHOUGH
TEMPERATURES ARE STILL NO EXPECTED TO WARM ABOVE ZERO.

OVER THE BRISTOL BAY AREA...A WINTER WEATHER ADVISORY FOR SNOW AND
BLOWING SNOW HAS BEEN ISSUED AS RADAR REFLECTIVITIES ARE ALREADY
SHOWING DECENT SNOW MOVING FROM SOUTH TO NORTH. AREAS NORTH AND
WEST OF KING SALMON (INCLUDING DILLINGHAM AND KOLIGANEK) WILL SEE
ANYWHERE FROM 5 TO 8 INCHES OF SNOW ACCUMULATION WHILE THE
REMAINDER OF THE ZONE WILL BE ON THE DRY SIDE...LARGELY FROM
DOWNSLOPING AS A WARM FRONT PUSHES NORTH. HOWEVER A FEW ISOLATED
SNOW SHOWERS NEAR KING SALMON CANNOT BE RULED OUT. STRONG WINDS
WILL ACCOMPANY THE SNOWFALL NORTH AND WEST OF KING SALMON WHICH
WILL ALLOW BLOWING SNOW CONDITIONS TO DEVELOP THAT WILL REDUCE
VISIBILITIES TO ONE HALF MILE OR LESS AT TIMES THROUGH TUESDAY
MORNING. AS SNOW TAPERS OFF TUESDAY MORNING...SKIES WILL
GRADUALLY CLEAR THROUGH THE REMAINDER OF THE WEEK WITH A BRIEF
WARM UP OBSERVED TUESDAY AND WEDNESDAY.

&&

.SHORT TERM FORECAST BERING SEA/ALEUTIANS (TONIGHT THROUGH THURSDAY
NIGHT)...

A BROAD COMPLEX LOW WILL CONTINUE TO SKIRT JUST SOUTH OF THE
ALEUTIAN ISLANDS THROUGH WEDNESDAY AFTERNOON BEFORE TAKING A
SOUTHERN TURN INTO THE NORTH PACIFIC AS A STRONG RIDGE OF HIGH
PRESSURE BEGINS TO SITUATE ITSELF ACROSS THE BERING SEA. A WARM
FRONT ASSOCIATED WITH THE COMPLEX LOW HAS MOVED NORTH OF THE
ALEUTIAN ISLANDS AND HAS STALLED JUST SOUTH OF THE PRIBILOF
ISLANDS. THIS IS EVIDENT IN THE SURFACE TEMPERATURE TRENDS OVER
THE PAST 24 HOURS. THE PRIBILOF ISLANDS ARE IN A "SWEET SPOT" AS
THEY CONTINUE TO SEE COLD NORTHEASTERLY FLOW AS PRECIPITATION WITH
THE DECAYING WARM FRONT SHIFTS NORTH. THIS WILL ALLOW THE PERIOD
OF SNOW THAT HAS BEEN OBSERVED THROUGHOUT THE DAY TO CONTINUE.
WITH THE BUILDING HIGH PRESSURE OVER THE WESTERN BERING...A STRONG
PRESSURE GRADIENT HAS DEVELOPED AND CREATED GUSTY WINDS ACROSS THE
PRIBILOF ISLANDS LEADING TO BLOWING SNOW CONDITIONS. THE CORE OF
THE STRONGEST WINDS WILL SHIFT WESTWARD TUESDAY AFTERNOON AND
BRING STRONG WINDS TO THE CENTRAL ALEUTIANS TUESDAY AFTERNOON
THROUGH THE REMAINDER OF THE WEEK.

&&

.LONG TERM FORECAST (DAYS 3 THROUGH 7)...
A WEAKENING FRONT/INVERTED TROUGH WILL BRING PRECIPITATION TO
KODIAK ISLAND AND AREAS ALONG THE NORTH GULF COAST TOWARDS THE
END OF THE WEEK...BUT OTHERWISE MUCH OF THE SOUTHERN MAINLAND WILL
REMAIN IN A DRY OFFSHORE FLOW PATTERN THROUGH FRIDAY AS A STOUT
UPPER RIDGE BUILDS OVER THE WESTERN BERING AND TEMPERATURES SLOWLY
MODERATE TO NEAR NORMAL VALUES.

FORECAST CONFIDENCE BEGINS TO DIMINISH THIS WEEKEND INTO NEXT WEEK
AS THE UPPER RIDGE MIGRATES EASTWARD AND EVOLVES INTO A CLOSED
UPPER HIGH OVER THE EASTERN BERING/WESTERN MAINLAND. WHERE THIS
FEATURE ULTIMATELY SETS UP WILL HAVE A LARGE IMPACT ON THE
NORTHWARD PROGRESSION OF A NORTH PACIFIC LOW MOVING TOWARDS THE
SOUTHERN GULF...AND THUS HAVE A LARGE IMPACT ON PRECIPITATION
CHANCES OVER THE MAINLAND. AT THIS POINT IT APPEARS THAT ANY
PRECIP WILL REMAIN FAR ENOUGH SOUTH TO MAINLY IMPACT AREAS FROM
THE ALASKA PENINSULA TO THE GULF COAST...WITH MUCH OF THE MAINLAND
AND BERING SEA REMAINING DRY AS PERSISTENT OFFSHORE FLOW KEEPS
GUSTY WINDS ALONG THE NORTH GULF COAST.

&&


.AFC WATCHES/WARNINGS/ADVISORIES...
PUBLIC...WIND CHILL ADVISORY 155. SNOW/BLOWING SNOW ADVISORY 161
         BLOWING SNOW ADVISORY 195.
MARINE...GALE WARNING 120 127 130 131 132 138 139 150 155 165 170
            172 173 175 176 177 179 185.
         HEAVY FRZ SPRAY 121 126 127 128 130 139 140 141 185.
FIRE WEATHER...NONE.

&&

$$

SYNOPSIS AND MODEL DISCUSSION...BC
SOUTHCENTRAL ALASKA...CC
SOUTHWEST ALASKA/BERING SEA/ALEUTIANS...MC
LONG TERM...CB





000
FXAK68 PAFC 261415
AFDAFC

SOUTHCENTRAL AND SOUTHWEST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE ANCHORAGE AK
515 AM AKST MON JAN 26 2015

.ANALYSIS AND UPPER LEVELS...
THE MAIN UPPER LEVEL TROUGH EXTENDS OUT OF AN UPPER LOW OVER THE
ARCTIC AND EXTENDS SOUTHWARD OVER THE COPPER RIVER BASIN AND
PRINCE WILLIAM SOUND THIS AFTERNOON. THERE IS A SECONDARY TROUGH
THAT IS DIGGING ACROSS THE BERING SEA AND WESTERN ALEUTIANS WHICH
IS KEEPING THE JET STREAM SOUTH OF THE AREA AND SERVING AS THE
FOCAL POINT FOR A SURFACE LOW THAT IS SOUTH OF THE ALEUTIANS AND
HEADING EASTWARD. THE FRONT ASSOCIATED WITH THIS SURFACE LOW IS
PUSHING NORTH OF THE ALEUTIANS INTO THE BERING SEA OVERNIGHT
TONIGHT. A WEAK SURFACE LOW DEVELOPED IN EASTERN PRINCE WILLIAM
SOUND EARLY THIS MORNING AND IS MOVING SLOWLY EASTWARD. THIS
FEATURE ENHANCED SNOW SHOWERS OVER THE VALDEZ AND CORDOVA AREAS
TODAY.

&&

.MODEL DISCUSSION...
MODELS INITIALIZE VERY WELL AND ARE SHOWING GOOD CONSISTENCY FOR
THE FIRST TWO DAYS BEFORE A COMPLEX LOW MOVING TOWARD THE AREA
FROM THE SOUTH TUESDAY NIGHT IS SHOWING QUITE A DIFFERENCE BETWEEN
MODEL SOLUTIONS. AS WITH THE COMPLEX LOW FROM LAST WEEK THE MODELS
HAVE MORE OR LESS A COMMON TROUGH AXIS WHERE THEY PLACE THE LOW.
HOWEVER THE MODELS ARE STRUGGLING WITH THE WAY THE LOW SPLITS ITS
DOUBLE CENTERS AND MODEL SOLUTIONS ARE HUNDREDS OF MILES APART.
THE GFS IS SHOWING ITS TYPICAL ERROR OF CONSOLIDATING ITS ENERGY
INTO A SINGLE LOW CENTER WHICH IS NOT LIKELY TO OCCUR.

&&

.SHORT TERM FORECAST SOUTHWEST ALASKA (TODAY THROUGH TUESDAY NIGHT)...
THE WIND CHILL ADVISORY ACROSS THE KUSKOKWIM DELTA IS BEING
VERIFIED THIS MORNING...WITH WIND CHILLS OF 40 BELOW TO 45 BELOW
ZERO BEING REPORTED. THE ADVISORY STILL LOOKS TO BE ON TRACK TO
EXPIRE AT NOON TODAY AS TEMPERATURES WARM...BRINGING WIND CHILLS
UP AS WELL. TEMPERATURES ARE GOING TO BEGIN TO MODERATE SOMEWHAT
OVER THE SOUTHWEST MAINLAND BEGINNING TONIGHT...AS A LOW IN THE
NORTH PACIFIC BRINGS SOME WARMER AIR NORTHWARD. THE BIGGEST
CHANGES WILL BE FELT OVER THE KUSKOKWIM DELTA AND BRISTOL BAY
TONIGHT...THEN FARTHER INLAND OVER THE LOWER KUSKOKWIM VALLEY ON
TUESDAY. HOWEVER...TEMPERATURES WILL STILL BE BELOW NORMAL THROUGH
THIS TIME.

AS THE AFOREMENTIONED LOW APPROACHES THE ALASKA PENINSULA FROM THE
SOUTH...SNOW WILL SPREAD OVER THE COASTAL AREAS OF BRISTOL BAY. WE
ARE STILL EXPECTING 3 TO 6 INCHES TO FALL IN THIS AREA...ALONG
WITH BLOWING SNOW AS GUSTY WINDS CONTINUE. INLAND AREAS OF BRISTOL
BAY SHOULD SEE MINIMAL SNOWFALL AS THE PRECIPITATION IS BLOCKED BY
THE ALEUTIAN RANGE.

&&

.SHORT TERM FORECAST BERING SEA/ALEUTIANS (TODAY THROUGH TUESDAY
NIGHT)...
TEMPERATURES WILL CONTINUE TO WARM ALONG THE EASTERN ALEUTIANS
AND ALASKA PENINSULA AS THE LOW MOVES TOWARD THE AREA TONIGHT AND
TUESDAY. THIS WILL KEEP PRECIPITATION TYPE AS MAINLY RAIN ACROSS
THIS AREA. FARTHER WEST...WINDS WILL INCREASE ON THE BACK SIDE OF
THE LOW FOR THE CENTRAL AND WESTERN ALEUTIANS FOR THE NEXT COUPLE
DAYS. THE PRIBILOFS WILL SEE SNOW CONTINUE TODAY AND
TONIGHT...THEN TRANSITION TO MORE SHOWERY TUESDAY AFTERNOON.

&&

.LONG TERM FORECAST (DAYS 3 THROUGH 7)...
A SERIES OF UPPER LEVEL WAVES ASSOCIATED WITH A NORTH PACIFIC LOW
SOUTH OF THE ALASKA PENINSULA WILL CONTINUE TO GENERATE SHOWERY
AND GUSTY CONDITIONS ALONG THE GULF COAST AND ALASKA PENINSULA
THROUGH THE END OF THE WEEK. COLDER AIR FILTERING DOWN OVER THE
CENTRAL AND EASTERN BERING/ALEUTIANS ON THE BACKSIDE OF THIS
SYSTEM WILL KEEP SOME GUSTY WINDS AND INSTABILITY SHOWERS OVER THE
AREA THROUGH THURSDAY AFTERNOON. RIDGING WILL THEN BUILD IN OVER
MUCH OF THE BERING FROM WEST TO EAST BY THE END OF THE WEEK...AND
BEGIN TO EXTEND OVER MAINLAND ALASKA DURING THE WEEKEND. THIS WILL
CONTAIN THE MAJORITY OF PRECIPITATION OVER THE NORTH PACIFIC AND
GULF OF ALASKA...AS WELL AS KEEP DRY AND COLD NORTHEASTERLY FLOW
OVER THE SOUTHWEST PART OF THE STATE. HOWEVER MODELS HAVE STARTED
TO KEY IN ON A WEAK FRONTAL SYSTEM TRACKING THROUGH THE NORTHERN
BERING AND INTO THE KUSKOKWIM DELTA COAST FRIDAY...WHICH COULD
BRING A BRIEF ROUND OF PRECIPITATION AND GUSTY WINDS TO THE AREA.
MODELS ARE ALSO INDICATING A WEAK SURFACE LOW TRACKING TOWARD THE
WESTERN ALEUTIANS SATURDAY MORNING...BRINGING SOME PRECIPITATION
TO THE AREA. HOWEVER FROM SATURDAY MORNING THROUGH EARLY NEXT
WEEK...THE MODELS BEGIN TO DIFFER IMMENSELY FROM EACH OTHER
REGARDING THE TRACK AND STRENGTH OF THIS SYSTEM. MODELS ARE ALSO
STRUGGLING WITH THE PLACEMENT OF ANOTHER LOW APPROACHING THE
SOUTHERN GULF OVER THE WEEKEND. THEREFORE WITH THESE DIFFERENCES
IN THE MODEL SOLUTIONS...FORECAST CONFIDENCE BEGINS TO DRASTICALLY
DIMINISH OVER THE WEEKEND.

&&


.AFC WATCHES/WARNINGS/ADVISORIES...
PUBLIC...WIND CHILL ADVISORY 155.
MARINE...GALE WARNING 130 132 138 150 155 160 165 173 175 176 177
          179 180.
         HEAVY FRZ SPRAY 121 127 129 130 139 140 141 160 179 180
          185.
FIRE WEATHER...NONE.

&&

$$

SYNOPSIS AND MODEL DISCUSSION...MTL
SOUTHCENTRAL ALASKA...MTL
SOUTHWEST ALASKA/BERING SEA/ALEUTIANS...MBS
LONG TERM...TP





000
FXAK68 PAFC 261415
AFDAFC

SOUTHCENTRAL AND SOUTHWEST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE ANCHORAGE AK
515 AM AKST MON JAN 26 2015

.ANALYSIS AND UPPER LEVELS...
THE MAIN UPPER LEVEL TROUGH EXTENDS OUT OF AN UPPER LOW OVER THE
ARCTIC AND EXTENDS SOUTHWARD OVER THE COPPER RIVER BASIN AND
PRINCE WILLIAM SOUND THIS AFTERNOON. THERE IS A SECONDARY TROUGH
THAT IS DIGGING ACROSS THE BERING SEA AND WESTERN ALEUTIANS WHICH
IS KEEPING THE JET STREAM SOUTH OF THE AREA AND SERVING AS THE
FOCAL POINT FOR A SURFACE LOW THAT IS SOUTH OF THE ALEUTIANS AND
HEADING EASTWARD. THE FRONT ASSOCIATED WITH THIS SURFACE LOW IS
PUSHING NORTH OF THE ALEUTIANS INTO THE BERING SEA OVERNIGHT
TONIGHT. A WEAK SURFACE LOW DEVELOPED IN EASTERN PRINCE WILLIAM
SOUND EARLY THIS MORNING AND IS MOVING SLOWLY EASTWARD. THIS
FEATURE ENHANCED SNOW SHOWERS OVER THE VALDEZ AND CORDOVA AREAS
TODAY.

&&

.MODEL DISCUSSION...
MODELS INITIALIZE VERY WELL AND ARE SHOWING GOOD CONSISTENCY FOR
THE FIRST TWO DAYS BEFORE A COMPLEX LOW MOVING TOWARD THE AREA
FROM THE SOUTH TUESDAY NIGHT IS SHOWING QUITE A DIFFERENCE BETWEEN
MODEL SOLUTIONS. AS WITH THE COMPLEX LOW FROM LAST WEEK THE MODELS
HAVE MORE OR LESS A COMMON TROUGH AXIS WHERE THEY PLACE THE LOW.
HOWEVER THE MODELS ARE STRUGGLING WITH THE WAY THE LOW SPLITS ITS
DOUBLE CENTERS AND MODEL SOLUTIONS ARE HUNDREDS OF MILES APART.
THE GFS IS SHOWING ITS TYPICAL ERROR OF CONSOLIDATING ITS ENERGY
INTO A SINGLE LOW CENTER WHICH IS NOT LIKELY TO OCCUR.

&&

.SHORT TERM FORECAST SOUTHWEST ALASKA (TODAY THROUGH TUESDAY NIGHT)...
THE WIND CHILL ADVISORY ACROSS THE KUSKOKWIM DELTA IS BEING
VERIFIED THIS MORNING...WITH WIND CHILLS OF 40 BELOW TO 45 BELOW
ZERO BEING REPORTED. THE ADVISORY STILL LOOKS TO BE ON TRACK TO
EXPIRE AT NOON TODAY AS TEMPERATURES WARM...BRINGING WIND CHILLS
UP AS WELL. TEMPERATURES ARE GOING TO BEGIN TO MODERATE SOMEWHAT
OVER THE SOUTHWEST MAINLAND BEGINNING TONIGHT...AS A LOW IN THE
NORTH PACIFIC BRINGS SOME WARMER AIR NORTHWARD. THE BIGGEST
CHANGES WILL BE FELT OVER THE KUSKOKWIM DELTA AND BRISTOL BAY
TONIGHT...THEN FARTHER INLAND OVER THE LOWER KUSKOKWIM VALLEY ON
TUESDAY. HOWEVER...TEMPERATURES WILL STILL BE BELOW NORMAL THROUGH
THIS TIME.

AS THE AFOREMENTIONED LOW APPROACHES THE ALASKA PENINSULA FROM THE
SOUTH...SNOW WILL SPREAD OVER THE COASTAL AREAS OF BRISTOL BAY. WE
ARE STILL EXPECTING 3 TO 6 INCHES TO FALL IN THIS AREA...ALONG
WITH BLOWING SNOW AS GUSTY WINDS CONTINUE. INLAND AREAS OF BRISTOL
BAY SHOULD SEE MINIMAL SNOWFALL AS THE PRECIPITATION IS BLOCKED BY
THE ALEUTIAN RANGE.

&&

.SHORT TERM FORECAST BERING SEA/ALEUTIANS (TODAY THROUGH TUESDAY
NIGHT)...
TEMPERATURES WILL CONTINUE TO WARM ALONG THE EASTERN ALEUTIANS
AND ALASKA PENINSULA AS THE LOW MOVES TOWARD THE AREA TONIGHT AND
TUESDAY. THIS WILL KEEP PRECIPITATION TYPE AS MAINLY RAIN ACROSS
THIS AREA. FARTHER WEST...WINDS WILL INCREASE ON THE BACK SIDE OF
THE LOW FOR THE CENTRAL AND WESTERN ALEUTIANS FOR THE NEXT COUPLE
DAYS. THE PRIBILOFS WILL SEE SNOW CONTINUE TODAY AND
TONIGHT...THEN TRANSITION TO MORE SHOWERY TUESDAY AFTERNOON.

&&

.LONG TERM FORECAST (DAYS 3 THROUGH 7)...
A SERIES OF UPPER LEVEL WAVES ASSOCIATED WITH A NORTH PACIFIC LOW
SOUTH OF THE ALASKA PENINSULA WILL CONTINUE TO GENERATE SHOWERY
AND GUSTY CONDITIONS ALONG THE GULF COAST AND ALASKA PENINSULA
THROUGH THE END OF THE WEEK. COLDER AIR FILTERING DOWN OVER THE
CENTRAL AND EASTERN BERING/ALEUTIANS ON THE BACKSIDE OF THIS
SYSTEM WILL KEEP SOME GUSTY WINDS AND INSTABILITY SHOWERS OVER THE
AREA THROUGH THURSDAY AFTERNOON. RIDGING WILL THEN BUILD IN OVER
MUCH OF THE BERING FROM WEST TO EAST BY THE END OF THE WEEK...AND
BEGIN TO EXTEND OVER MAINLAND ALASKA DURING THE WEEKEND. THIS WILL
CONTAIN THE MAJORITY OF PRECIPITATION OVER THE NORTH PACIFIC AND
GULF OF ALASKA...AS WELL AS KEEP DRY AND COLD NORTHEASTERLY FLOW
OVER THE SOUTHWEST PART OF THE STATE. HOWEVER MODELS HAVE STARTED
TO KEY IN ON A WEAK FRONTAL SYSTEM TRACKING THROUGH THE NORTHERN
BERING AND INTO THE KUSKOKWIM DELTA COAST FRIDAY...WHICH COULD
BRING A BRIEF ROUND OF PRECIPITATION AND GUSTY WINDS TO THE AREA.
MODELS ARE ALSO INDICATING A WEAK SURFACE LOW TRACKING TOWARD THE
WESTERN ALEUTIANS SATURDAY MORNING...BRINGING SOME PRECIPITATION
TO THE AREA. HOWEVER FROM SATURDAY MORNING THROUGH EARLY NEXT
WEEK...THE MODELS BEGIN TO DIFFER IMMENSELY FROM EACH OTHER
REGARDING THE TRACK AND STRENGTH OF THIS SYSTEM. MODELS ARE ALSO
STRUGGLING WITH THE PLACEMENT OF ANOTHER LOW APPROACHING THE
SOUTHERN GULF OVER THE WEEKEND. THEREFORE WITH THESE DIFFERENCES
IN THE MODEL SOLUTIONS...FORECAST CONFIDENCE BEGINS TO DRASTICALLY
DIMINISH OVER THE WEEKEND.

&&


.AFC WATCHES/WARNINGS/ADVISORIES...
PUBLIC...WIND CHILL ADVISORY 155.
MARINE...GALE WARNING 130 132 138 150 155 160 165 173 175 176 177
          179 180.
         HEAVY FRZ SPRAY 121 127 129 130 139 140 141 160 179 180
          185.
FIRE WEATHER...NONE.

&&

$$

SYNOPSIS AND MODEL DISCUSSION...MTL
SOUTHCENTRAL ALASKA...MTL
SOUTHWEST ALASKA/BERING SEA/ALEUTIANS...MBS
LONG TERM...TP




000
FXAK68 PAFC 261415 CCA
AFDAFC

SOUTHCENTRAL AND SOUTHWEST ALASKA FORECAST DISCUSSION...CORRECTED
NATIONAL WEATHER SERVICE ANCHORAGE AK
515 AM AKST MON JAN 26 2015

.ANALYSIS AND UPPER LEVELS...
A CLOSED COLD UPPER LOW PRESSURE OVER THE ARCTIC OCEAN EXTENDS A
TROUGH AXIS SOUTHWARD OVER MUCH OF THE STATE...RESPONSIBLE FOR THE
CURRENT ARCTIC AIR OUTBREAK. OVER THE BERING A REX BLOCK HAS
STALLED THE PATTERN WITH A CLOSED UPPER HIGH OVER THE CHUKCHI
PENINSULA AND A CLOSED UPPER LOW SOUTH OF THE ALEUTIANS. THE
CONFIGURATION IS STALLING OR SLOWING THE PATTERN. A COUPLE
SHORTWAVE TROUGHS ARE VISIBLE ON WATER VAPOR PROPAGATING THROUGH
THE FLOW DOWNSTREAM OF THE UPPER LOW TOWARD THE ALASKA PENINSULA.
THE JET STREAM IS WELL TO THE SOUTH AND THE TROUGH LOOKS RATHER
DISORGANIZED.

AT THE SURFACE...THE COLDEST AIR OF THE SEASON RESIDES ACROSS MUCH
OF THE STATE RESULTING IN OUTFLOW WINDS ACROSS THE NORTH GULF
COAST AND MOSTLY CLOUDLESS SKIES OVER MUCH OF THE
SOUTHCENTRAL...THOUGH SOME PATCHY LOW CLOUDS ARE MANAGING TO
LINGER AROUND KNIK ARM. A FRONTAL BOUNDARY REMAINS DRAPED ACROSS
THE ALEUTIANS BRINGING ROUNDS OF SNOW TO THE CHAIN ALONG WITH GALE
FORCE WINDS.

&&

.MODEL DISCUSSION...
IN THE UPPER LEVELS...GUIDANCE HAS THE SAME GENERAL IDEA WITH THE
MATURE UPPER LOW SOUTH OF THE ALEUTIANS OUTSIDE OF SOME SMALL
DISCREPANCIES ON LOW/TRIPLE POINT CENTERS. THE POSITION OF THE
SURFACE REFLECTION OF THE NEXT STRONG WAVE MOVING TOWARD THE
ALASKA PENINSULA IS IN GREATER QUESTION BUT DIFFERENCES SEEM
NEGLIGIBLE IN TERMS OF IMPACTS TO THE FORECAST.

&&

.SHORT TERM FORECAST SOUTHCENTRAL ALASKA (DAYS 1 AND 2)...
ARCTIC AIR HAS SET UP SHOP OVER THE SOUTHCENTRAL AND WILL CONTINUE
TO BE THE MAIN SENSIBLE WEATHER FOR THE NEXT COUPLE DAYS. HIGH
LEVEL CLOUDS STREAMING OVERHEAD FROM A PACIFIC SYSTEM COULD
INSOLATE A LITTLE BIT BUT TEMPERATURES SHOULD STAY CHILLY. OUTFLOW
WINDS WILL CONTINUE ACROSS THE NORTH GULF COAST AS A WEAK FRONT
APPROACHES THE SOUTHERN GULF TONIGHT.

&&

.SHORT TERM FORECAST SOUTHWEST ALASKA (TODAY THROUGH TUESDAY NIGHT)...
THE WIND CHILL ADVISORY ACROSS THE KUSKOKWIM DELTA IS BEING
VERIFIED THIS MORNING...WITH WIND CHILLS OF 40 BELOW TO 45 BELOW
ZERO BEING REPORTED. THE ADVISORY STILL LOOKS TO BE ON TRACK TO
EXPIRE AT NOON TODAY AS TEMPERATURES WARM...BRINGING WIND CHILLS
UP AS WELL. TEMPERATURES ARE GOING TO BEGIN TO MODERATE SOMEWHAT
OVER THE SOUTHWEST MAINLAND BEGINNING TONIGHT...AS A LOW IN THE
NORTH PACIFIC BRINGS SOME WARMER AIR NORTHWARD. THE BIGGEST
CHANGES WILL BE FELT OVER THE KUSKOKWIM DELTA AND BRISTOL BAY
TONIGHT...THEN FARTHER INLAND OVER THE LOWER KUSKOKWIM VALLEY ON
TUESDAY. HOWEVER...TEMPERATURES WILL STILL BE BELOW NORMAL THROUGH
THIS TIME.

AS THE AFOREMENTIONED LOW APPROACHES THE ALASKA PENINSULA FROM THE
SOUTH...SNOW WILL SPREAD OVER THE COASTAL AREAS OF BRISTOL BAY. WE
ARE STILL EXPECTING 3 TO 6 INCHES TO FALL IN THIS AREA...ALONG
WITH BLOWING SNOW AS GUSTY WINDS CONTINUE. INLAND AREAS OF BRISTOL
BAY SHOULD SEE MINIMAL SNOWFALL AS THE PRECIPITATION IS BLOCKED BY
THE ALEUTIAN RANGE.

&&

.SHORT TERM FORECAST BERING SEA/ALEUTIANS (TODAY THROUGH TUESDAY
NIGHT)...
TEMPERATURES WILL CONTINUE TO WARM ALONG THE EASTERN ALEUTIANS
AND ALASKA PENINSULA AS THE LOW MOVES TOWARD THE AREA TONIGHT AND
TUESDAY. THIS WILL KEEP PRECIPITATION TYPE AS MAINLY RAIN ACROSS
THIS AREA. FARTHER WEST...WINDS WILL INCREASE ON THE BACK SIDE OF
THE LOW FOR THE CENTRAL AND WESTERN ALEUTIANS FOR THE NEXT COUPLE
DAYS. THE PRIBILOFS WILL SEE SNOW CONTINUE TODAY AND
TONIGHT...THEN TRANSITION TO MORE SHOWERY TUESDAY AFTERNOON.

&&

.LONG TERM FORECAST (DAYS 3 THROUGH 7)...
A SERIES OF UPPER LEVEL WAVES ASSOCIATED WITH A NORTH PACIFIC LOW
SOUTH OF THE ALASKA PENINSULA WILL CONTINUE TO GENERATE SHOWERY
AND GUSTY CONDITIONS ALONG THE GULF COAST AND ALASKA PENINSULA
THROUGH THE END OF THE WEEK. COLDER AIR FILTERING DOWN OVER THE
CENTRAL AND EASTERN BERING/ALEUTIANS ON THE BACKSIDE OF THIS
SYSTEM WILL KEEP SOME GUSTY WINDS AND INSTABILITY SHOWERS OVER THE
AREA THROUGH THURSDAY AFTERNOON. RIDGING WILL THEN BUILD IN OVER
MUCH OF THE BERING FROM WEST TO EAST BY THE END OF THE WEEK...AND
BEGIN TO EXTEND OVER MAINLAND ALASKA DURING THE WEEKEND. THIS WILL
CONTAIN THE MAJORITY OF PRECIPITATION OVER THE NORTH PACIFIC AND
GULF OF ALASKA...AS WELL AS KEEP DRY AND COLD NORTHEASTERLY FLOW
OVER THE SOUTHWEST PART OF THE STATE. HOWEVER MODELS HAVE STARTED
TO KEY IN ON A WEAK FRONTAL SYSTEM TRACKING THROUGH THE NORTHERN
BERING AND INTO THE KUSKOKWIM DELTA COAST FRIDAY...WHICH COULD
BRING A BRIEF ROUND OF PRECIPITATION AND GUSTY WINDS TO THE AREA.
MODELS ARE ALSO INDICATING A WEAK SURFACE LOW TRACKING TOWARD THE
WESTERN ALEUTIANS SATURDAY MORNING...BRINGING SOME PRECIPITATION
TO THE AREA. HOWEVER FROM SATURDAY MORNING THROUGH EARLY NEXT
WEEK...THE MODELS BEGIN TO DIFFER IMMENSELY FROM EACH OTHER
REGARDING THE TRACK AND STRENGTH OF THIS SYSTEM. MODELS ARE ALSO
STRUGGLING WITH THE PLACEMENT OF ANOTHER LOW APPROACHING THE
SOUTHERN GULF OVER THE WEEKEND. THEREFORE WITH THESE DIFFERENCES
IN THE MODEL SOLUTIONS...FORECAST CONFIDENCE BEGINS TO DRASTICALLY
DIMINISH OVER THE WEEKEND.

&&


.AFC WATCHES/WARNINGS/ADVISORIES...
PUBLIC...WIND CHILL ADVISORY 155.
MARINE...GALE WARNING 130 132 138 150 155 160 165 173 175 176 177
          179 180.
         HEAVY FRZ SPRAY 121 127 129 130 139 140 141 160 179 180
          185.
FIRE WEATHER...NONE.

&&

$$

SYNOPSIS AND MODEL DISCUSSION...MTL
SOUTHCENTRAL ALASKA...MTL
SOUTHWEST ALASKA/BERING SEA/ALEUTIANS...MBS
LONG TERM...TP




000
FXAK68 PAFC 260038
AFDAFC

SOUTHCENTRAL AND SOUTHWEST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE ANCHORAGE AK
338 PM AKST SUN JAN 25 2015

.ANALYSIS AND UPPER LEVELS...

THE MAIN UPPER LEVEL TROUGH EXTENDS OUT OF AN UPPER LOW OVER THE
ARCTIC AND EXTENDS SOUTHWARD OVER THE COPPER RIVER BASIN AND
PRINCE WILLIAM SOUND THIS AFTERNOON. THERE IS A SECONDARY TROUGH
THAT IS DIGGING ACROSS THE BERING SEA AND WESTERN ALEUTIANS WHICH
IS KEEPING THE JET STREAM SOUTH OF THE AREA AND SERVING AS THE
FOCAL POINT FOR A SURFACE LOW THAT IS SOUTH OF THE ALEUTIANS AND
HEADING EASTWARD. THE FRONT ASSOCIATED WITH THIS SURFACE LOW IS
PUSHING NORTH OF THE ALEUTIANS INTO THE BERING SEA OVERNIGHT
TONIGHT.
A WEAK SURFACE LOW DEVELOPED IN EASTERN PRINCE WILLIAM SOUND EARLY
THIS MORNING AND IS MOVING SLOWLY EASTWARD. THIS FEATURE ENHANCED
SNOW SHOWERS OVER THE VALDEZ AND CORDOVA AREAS TODAY.

&&

.MODEL DISCUSSION...
MODELS INITIALIZE VERY WELL AND ARE SHOWING GOOD CONSISTENCY FOR
THE FIRST TWO DAYS BEFORE A COMPLEX LOW MOVING TOWARD THE AREA
FROM THE SOUTH TUESDAY NIGHT IS SHOWING QUITE A DIFFERENCE BETWEEN
MODEL SOLUTIONS. AS WITH THE COMPLEX LOW FROM LAST WEEK THE MODELS
HAVE MORE OR LESS A COMMON TROUGH AXIS WHERE THEY PLACE THE LOW.
HOWEVER THE MODELS ARE STRUGGLING WITH THE WAY THE LOW SPLITS ITS
DOUBLE CENTERS AND MODEL SOLUTIONS ARE HUNDREDS OF MILES APART.
THE GFS IS SHOWING ITS TYPICAL ERROR OF CONSOLIDATING ITS ENERGY
INTO A SINGLE LOW CENTER WHICH IS NOT LIKELY TO OCCUR.

&&

.SHORT TERM FORECAST SOUTHCENTRAL ALASKA (DAYS 1 AND 2)...

BITTER COLD CONTINUES TO SETTLE OVER SOUTHCENTRAL TONIGHT INTO
TUESDAY. TONIGHT`S LOWS WILL BE COLDEST OF THE SEASON OVER
ANCHORAGE...AND SHOULD EASILY BREAK THE LONG STREAK OF
CONSECUTIVE DAYS ZERO OR ABOVE FOR TED STEVENS INTERNATIONAL
AIRPORT. THE COLD WILL REMAIN IN PLACE AT LEAST THROUGH TUESDAY
NIGHT...WITH MODEST IMPROVEMENTS TOWARD MIDWEEK.

WITH SUCH A DEEP POCKET OF COLD AIR OVER THE SOUTHERN
INTERIOR...GUSTY OUTFLOW GAP WINDS CAN BE EXPECTED TO CONTINUE THE
NEXT FEW DAYS...BUT GENERALLY BELOW STRONG WIND CRITERIA WITH A
LACK OF UPPER LEVEL SUPPORT TO ENHANCE THESE WINDS.

PRECIPITATION SHOULD REMAIN CONFINED TO COLD ADVECTION SNOW SHOWERS
ALONG LOWER COOK INLET...THE NORTHERN GULF...SHELIKOF STRAIT...PRINCE
WILLIAM SOUND...AND MAINLY SOUTHERN PARTS OF KODIAK ISLAND...WITH
THE MORE SUSTAINED SHOWERS FOCUSED NEAR A CONVERGENCE BOUNDARY
ALONG THE NORTHERN GULF LATE TONIGHT THROUGH TUESDAY NIGHT.

&&

.SHORT TERM FORECAST SOUTHWEST ALASKA (TODAY AND MONDAY)...
NOW THAT THE ARCTIC AIR MASS HAS SET UP OVER THE INTERIOR
SOUTHWEST TEMPERATURES WILL STRUGGLE TO RECOVER MUCH TODAY WITH
LITTLE CHANGE IN WIND OR CLOUD COVER EXPECTED. THIS WILL CHANGE
TONIGHT AS A WAVE DEVELOPS IN THE BERING...INCREASING THE OFFSHORE
WINDS THROUGHOUT THE KUSKOKWIM DELTA AND BRISTOL BAY. THIS WILL
CREATE DANGEROUSLY LOW WIND CHILLS LATE TONIGHT AND TOMORROW
MORNING...ESPECIALLY FOR THE KUSKOKWIM DELTA WHERE A WIND CHILL
ADVISORY HAS BEEN ISSUED FOR WIND CHILLS AS LOW AS 45 BELOW ZERO.
TEMPERATURES WILL THEN SLOWLY RISE ON MONDAY AS WINDS AND CLOUDS
INCREASE. THIS INCREASING CLOUD COVER WILL MOVE IN AS A RESULT AS
A SHORTWAVE MOVING IN FROM THE AKPEN. THIS WILL BRING
ACCUMULATING SNOW TO THE WESTERN BRISTOL BAY FROM LATE MONDAY INTO
TUESDAY. THIS WAVE HAS TO POTENTIAL TO BRING SIGNIFICANT
ACCUMULATIONS TO THE DILLINGHAM AREA BY TUESDAY MORNING...HOWEVER
DUE TO SOME DISAGREEMENT IN HOW FAR EAST THE SNOW WILL REACH AND
STRENGTH OF THE UPPER LEVEL WAVE...ITS TOO SOON TO SAY EXACTLY HOW
MUCH SNOW COULD FALL.

&&

.SHORT TERM FORECAST BERING SEA/ALEUTIANS (TODAY AND MONDAY)...
THE FRONT ASSOCIATED WITH THE LOW CURRENTLY JUST SOUTH WILL
CONTINUE TO BRING RAIN AND SNOW FROM THE CENTRAL ALEUTIANS...BECOMING
SNOW AS IT SPREADS INTO THE EASTERN ALEUTIANS AND AKPEN BY THIS
LATE THIS AFTERNOON. THIS SYSTEM WILL THEN SPREAD INTO THE BERING
AND TOWARDS THE PRIBILOFS THIS EVENING...HOWEVER THE MODELS HAVE
TRENDED FURTHER SOUTH AND MUCH LIGHTER WITH THE SNOWFALL AS IT
APPROACHES THE ISLANDS BY MONDAY MORNING. IT IS FOR THIS
REASON...AND BECAUSE OF THE LACK OF CURRENT TRANSPORTABLE SNOW AND
UNSEASONABLY WARM WATERS IN THE BERING THAT THE BLIZZARD WATCH
THERE WAS CANCELLED THIS MORNING. THERE STILL WILL BE AREAS OF
BLOWING SNOW AS STRONG WINDS KICK UP WHATEVER DOES FALL...HOWEVER
AT THIS POINT IT DOES NOT APPEAR THIS WILL BE ENOUGH TO CREATE
BLIZZARD CONDITIONS.

&&

.LONG TERM FORECAST (DAYS 3 THROUGH 7)...
RIDGING WILL BUILD IN OVER THE BERING AND EXTEND OVER MAINLAND
ALASKA BY THE END OF THE WEEK. THIS WILL KEEP THE MAJORITY OF THE
PRECIPITATION OVER THE NORTH PACIFIC AND GULF OF ALASKA.
ADDITIONALLY...THE RIDGING WILL KEEP DRY AND COLD NORTHEASTERLY
FLOW OVER THE SOUTHWEST PART OF THE STATE. THIS PATTERN WILL
CONTINUE INTO THE WEEKEND UNTIL A LOW FROM NORTHEASTERN RUSSIA
MOVES INTO MAINLAND ALASKA.

&&


.AFC WATCHES/WARNINGS/ADVISORIES...
PUBLIC...WIND CHILL ADVISORY 155.
MARINE...GALE WARNING 130 160 165 170 175 176 177 178 179 180.
         HEAVY FRZ SPRAY 121 125 126 127 128 129 130 139 140 141
           160 165 179 180 185.
FIRE WEATHER...NONE.

&&

$$

SYNOPSIS AND MODEL DISCUSSION...EZ
SOUTHCENTRAL ALASKA...CC
SOUTHWEST ALASKA/BERING SEA/ALEUTIANS...MC
LONG TERM...DK




000
FXAK68 PAFC 260038
AFDAFC

SOUTHCENTRAL AND SOUTHWEST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE ANCHORAGE AK
338 PM AKST SUN JAN 25 2015

.ANALYSIS AND UPPER LEVELS...

THE MAIN UPPER LEVEL TROUGH EXTENDS OUT OF AN UPPER LOW OVER THE
ARCTIC AND EXTENDS SOUTHWARD OVER THE COPPER RIVER BASIN AND
PRINCE WILLIAM SOUND THIS AFTERNOON. THERE IS A SECONDARY TROUGH
THAT IS DIGGING ACROSS THE BERING SEA AND WESTERN ALEUTIANS WHICH
IS KEEPING THE JET STREAM SOUTH OF THE AREA AND SERVING AS THE
FOCAL POINT FOR A SURFACE LOW THAT IS SOUTH OF THE ALEUTIANS AND
HEADING EASTWARD. THE FRONT ASSOCIATED WITH THIS SURFACE LOW IS
PUSHING NORTH OF THE ALEUTIANS INTO THE BERING SEA OVERNIGHT
TONIGHT.
A WEAK SURFACE LOW DEVELOPED IN EASTERN PRINCE WILLIAM SOUND EARLY
THIS MORNING AND IS MOVING SLOWLY EASTWARD. THIS FEATURE ENHANCED
SNOW SHOWERS OVER THE VALDEZ AND CORDOVA AREAS TODAY.

&&

.MODEL DISCUSSION...
MODELS INITIALIZE VERY WELL AND ARE SHOWING GOOD CONSISTENCY FOR
THE FIRST TWO DAYS BEFORE A COMPLEX LOW MOVING TOWARD THE AREA
FROM THE SOUTH TUESDAY NIGHT IS SHOWING QUITE A DIFFERENCE BETWEEN
MODEL SOLUTIONS. AS WITH THE COMPLEX LOW FROM LAST WEEK THE MODELS
HAVE MORE OR LESS A COMMON TROUGH AXIS WHERE THEY PLACE THE LOW.
HOWEVER THE MODELS ARE STRUGGLING WITH THE WAY THE LOW SPLITS ITS
DOUBLE CENTERS AND MODEL SOLUTIONS ARE HUNDREDS OF MILES APART.
THE GFS IS SHOWING ITS TYPICAL ERROR OF CONSOLIDATING ITS ENERGY
INTO A SINGLE LOW CENTER WHICH IS NOT LIKELY TO OCCUR.

&&

.SHORT TERM FORECAST SOUTHCENTRAL ALASKA (DAYS 1 AND 2)...

BITTER COLD CONTINUES TO SETTLE OVER SOUTHCENTRAL TONIGHT INTO
TUESDAY. TONIGHT`S LOWS WILL BE COLDEST OF THE SEASON OVER
ANCHORAGE...AND SHOULD EASILY BREAK THE LONG STREAK OF
CONSECUTIVE DAYS ZERO OR ABOVE FOR TED STEVENS INTERNATIONAL
AIRPORT. THE COLD WILL REMAIN IN PLACE AT LEAST THROUGH TUESDAY
NIGHT...WITH MODEST IMPROVEMENTS TOWARD MIDWEEK.

WITH SUCH A DEEP POCKET OF COLD AIR OVER THE SOUTHERN
INTERIOR...GUSTY OUTFLOW GAP WINDS CAN BE EXPECTED TO CONTINUE THE
NEXT FEW DAYS...BUT GENERALLY BELOW STRONG WIND CRITERIA WITH A
LACK OF UPPER LEVEL SUPPORT TO ENHANCE THESE WINDS.

PRECIPITATION SHOULD REMAIN CONFINED TO COLD ADVECTION SNOW SHOWERS
ALONG LOWER COOK INLET...THE NORTHERN GULF...SHELIKOF STRAIT...PRINCE
WILLIAM SOUND...AND MAINLY SOUTHERN PARTS OF KODIAK ISLAND...WITH
THE MORE SUSTAINED SHOWERS FOCUSED NEAR A CONVERGENCE BOUNDARY
ALONG THE NORTHERN GULF LATE TONIGHT THROUGH TUESDAY NIGHT.

&&

.SHORT TERM FORECAST SOUTHWEST ALASKA (TODAY AND MONDAY)...
NOW THAT THE ARCTIC AIR MASS HAS SET UP OVER THE INTERIOR
SOUTHWEST TEMPERATURES WILL STRUGGLE TO RECOVER MUCH TODAY WITH
LITTLE CHANGE IN WIND OR CLOUD COVER EXPECTED. THIS WILL CHANGE
TONIGHT AS A WAVE DEVELOPS IN THE BERING...INCREASING THE OFFSHORE
WINDS THROUGHOUT THE KUSKOKWIM DELTA AND BRISTOL BAY. THIS WILL
CREATE DANGEROUSLY LOW WIND CHILLS LATE TONIGHT AND TOMORROW
MORNING...ESPECIALLY FOR THE KUSKOKWIM DELTA WHERE A WIND CHILL
ADVISORY HAS BEEN ISSUED FOR WIND CHILLS AS LOW AS 45 BELOW ZERO.
TEMPERATURES WILL THEN SLOWLY RISE ON MONDAY AS WINDS AND CLOUDS
INCREASE. THIS INCREASING CLOUD COVER WILL MOVE IN AS A RESULT AS
A SHORTWAVE MOVING IN FROM THE AKPEN. THIS WILL BRING
ACCUMULATING SNOW TO THE WESTERN BRISTOL BAY FROM LATE MONDAY INTO
TUESDAY. THIS WAVE HAS TO POTENTIAL TO BRING SIGNIFICANT
ACCUMULATIONS TO THE DILLINGHAM AREA BY TUESDAY MORNING...HOWEVER
DUE TO SOME DISAGREEMENT IN HOW FAR EAST THE SNOW WILL REACH AND
STRENGTH OF THE UPPER LEVEL WAVE...ITS TOO SOON TO SAY EXACTLY HOW
MUCH SNOW COULD FALL.

&&

.SHORT TERM FORECAST BERING SEA/ALEUTIANS (TODAY AND MONDAY)...
THE FRONT ASSOCIATED WITH THE LOW CURRENTLY JUST SOUTH WILL
CONTINUE TO BRING RAIN AND SNOW FROM THE CENTRAL ALEUTIANS...BECOMING
SNOW AS IT SPREADS INTO THE EASTERN ALEUTIANS AND AKPEN BY THIS
LATE THIS AFTERNOON. THIS SYSTEM WILL THEN SPREAD INTO THE BERING
AND TOWARDS THE PRIBILOFS THIS EVENING...HOWEVER THE MODELS HAVE
TRENDED FURTHER SOUTH AND MUCH LIGHTER WITH THE SNOWFALL AS IT
APPROACHES THE ISLANDS BY MONDAY MORNING. IT IS FOR THIS
REASON...AND BECAUSE OF THE LACK OF CURRENT TRANSPORTABLE SNOW AND
UNSEASONABLY WARM WATERS IN THE BERING THAT THE BLIZZARD WATCH
THERE WAS CANCELLED THIS MORNING. THERE STILL WILL BE AREAS OF
BLOWING SNOW AS STRONG WINDS KICK UP WHATEVER DOES FALL...HOWEVER
AT THIS POINT IT DOES NOT APPEAR THIS WILL BE ENOUGH TO CREATE
BLIZZARD CONDITIONS.

&&

.LONG TERM FORECAST (DAYS 3 THROUGH 7)...
RIDGING WILL BUILD IN OVER THE BERING AND EXTEND OVER MAINLAND
ALASKA BY THE END OF THE WEEK. THIS WILL KEEP THE MAJORITY OF THE
PRECIPITATION OVER THE NORTH PACIFIC AND GULF OF ALASKA.
ADDITIONALLY...THE RIDGING WILL KEEP DRY AND COLD NORTHEASTERLY
FLOW OVER THE SOUTHWEST PART OF THE STATE. THIS PATTERN WILL
CONTINUE INTO THE WEEKEND UNTIL A LOW FROM NORTHEASTERN RUSSIA
MOVES INTO MAINLAND ALASKA.

&&


.AFC WATCHES/WARNINGS/ADVISORIES...
PUBLIC...WIND CHILL ADVISORY 155.
MARINE...GALE WARNING 130 160 165 170 175 176 177 178 179 180.
         HEAVY FRZ SPRAY 121 125 126 127 128 129 130 139 140 141
           160 165 179 180 185.
FIRE WEATHER...NONE.

&&

$$

SYNOPSIS AND MODEL DISCUSSION...EZ
SOUTHCENTRAL ALASKA...CC
SOUTHWEST ALASKA/BERING SEA/ALEUTIANS...MC
LONG TERM...DK





000
FXAK68 PAFC 251434
AFDAFC

SOUTHCENTRAL AND SOUTHWEST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE ANCHORAGE AK
534 AM AKST SUN JAN 25 2015

.ANALYSIS AND UPPER LEVELS...
THE LONGWAVE TROUGH RESPONSIBLE FOR THE ARCTIC AIR INTRUSION OVER
THE SOUTHERN MAINLAND HAS BEEN DIVIDED INTO A COUPLE DIFFERENT
TROUGH AXIS. THE FIRST IS PROPAGATING OVER THE COPPER RIVER BASIN
AND REPRESENTS MOST OF THE ENERGY OF THIS LONGWAVE. BEHIND THE
WAVE...DRYING IS OCCURRING OVER THE COOK INLET REGION WITH SOME
LOW/MID CLOUDS BANKING UP AGAINST THE CHUGACH. OUTFLOW WINDS ARE
CRANKING IN WHITTIER AND SEWARD AS ARCTIC AIR FLOWS THROUGH THE
CHUGACH. SOME OF THE COLDEST TEMPERATURES OF THE SEASON ARE
SETTLING IN OVER COOK INLET...EXAGGERATED WHERE CLEARING HAS
ALLOWED FOR EFFICIENT RADIATIONAL COOLING. HOW FAR TEMPERATURES
FALL BEFORE SUNRISE WILL BE DEPENDENT ON AMOUNT OF CLEARING OVER
THE AREA.

FURTHER OUT WEST...A LARGE MATURE LOW SPINS SOUTH OF THE ALEUTIAN
ISLANDS WITH A FRONT DRAPED OVER THE CHAIN. THIS SYSTEM IS NOT
MAKING MUCH NORTHWARD PROGRESS AS RIDGING TO ITS NORTH IS MAKING A
NEAR REX BLOCK OVER THE BERING SEA. OUTFLOW WINDS AND BELOW NORMAL
TEMPERATURES CONTINUE FOR THE SOUTHWEST MAINLAND.

&&

.MODEL DISCUSSION...
IN THE UPPER LEVELS GUIDANCE IS IN GREAT AGREEMENT WITH THE HEIGHT
FIELD THROUGH MID-WEEK. SLIGHT DIFFERENCES IN LOW CENTER POSITIONS
STILL EXIST AS WELL AS TRIPLE POINT LOW FORMATION DIFFERENCES BUT
FOR THE MOST PART GUIDANCE SHOWING THE SAME GENERAL SOLUTION. THE
BIGGEST DIFFERENCES ARE IN FRONTAL POSITION OVER THE BERING SEA
AND HOW MUCH PRECIPITATION FALLS OVER THE PRIBILOF ISLANDS THEN
EVENTUALLY THE SOUTHWESTERN MAINLAND.

&&

.SHORT TERM FORECAST SOUTHCENTRAL ALASKA (DAYS 1 AND 2)...
LINGERING CLOUDS OVER THE MATANUSKA AND SUSITNA VALLEY WILL
DIMINISH TODAY LEADING TO CONTINUED COLDER CONDITIONS. OUTFLOW
WINDS WILL CONTINUE ACROSS THE NORTH GULF COAST AS THE PRESSURE
GRADIENT REMAINS FAVORABLE AND ARCTIC AIR IS ENTRENCHED OVER THE
MAINLAND. THE COPPER RIVER BASIN WILL HAVE LOW AND MID LEVEL
CLOUDS LINGER THE LONGEST TODAY BUT SHOULD CLEAR OUT BY THE
NIGHTTIME HOURS WHEN TEMPERATURE WILL PLUMMET UNDER LIGHT WINDS.
DRY...CLEAR...AND COLD CONDITIONS WILL CONTINUE FOR THE NEXT
COUPLE DAYS. A FRONT WILL ENTER THE GULF LATE MONDAY.

&&

.SHORT TERM FORECAST SOUTHWEST ALASKA (DAYS 1 AND 2)...
NOW THAT THE ARCTIC AIRMASS HAS SET UP OVER THE INTERIOR
SOUTHWEST TEMPERATURES WILL STRUGGLE TO RECOVER MUCH TODAY WITH
LITTLE CHANGE IN WIND OR CLOUDCOVER EXPECTED. THIS WILL CHANGE
TONIGHT AS A WAVE DEVELOPS IN THE BERING...INCREASING THE OFFSHORE
WINDS THROUGHOUT THE KUSKOKWIM DELTA AND BRISTOL BAY. THIS WILL
CREATE DANGEROUSLY LOW WIND CHILLS LATE TONIGHT AND TOMORROW
MORNING...ESPECIALLY FOR THE KUSKOKWIM DELTA WHERE A WIND CHILL
ADVISORY HAS BEEN ISSUED FOR WIND CHILLS AS LOW AS 45 BELOW ZERO.
TEMPERATURES WILL THEN SLOWLY RISE ON MONDAY AS WINDS AND CLOUDS
INCREASE. THIS INCREASING CLOUDCOVER WILL MOVE IN AS A RESULT AS A
SHORTWAVE MOVING IN FROM THE AKPEN. THIS WILL BRING ACCUMULATING
SNOW TO THE WESTERN BRISTOL BAY FROM LATE MONDAY INTO TUESDAY.
THIS WAVE HAS TO POTENTIAL TO BRING SIGNIFICANT ACCUMULATIONS TO
THE DILLINGHAM AREA BY TUESDAY MORNING...HOWEVER DUE TO SOME
DISAGREEMENT IN HOW FAR EAST THE SNOW WILL REACH AND STRENGTH OF
THE UPPER LEVEL WAVE...ITS TOO SOON TO SAY EXACTLY HOW MUCH SNOW
COULD FALL.

&&

.SHORT TERM FORECAST BERING SEA/ALEUTIANS (DAYS 1 AND 2)...
THE FRONT ASSOCIATED WITH THE LOW CURRENTLY JUST SOUTH WILL
CONTINUE TO BRING RAIN AND SNOW FROM THE CENTRAL
ALEUTIANS...BECOMING SNOW AS IT SPREADS INTO THE EASTERN ALEUTIANS
AND AKPEN BY THIS LATE THIS AFTERNOON. THIS SYSTEM WILL THEN
SPREAD INTO THE BERING AND TOWARDS THE PRIBILOFS THIS
EVENING...HOWEVER THE MODELS HAVE TRENDED FURTHER SOUTH AND MUCH
LIGHTER WITH THE SNOWFALL AS IT APPROACHES THE ISLANDS BY MONDAY
MORNING. IT IS FOR THIS REASON...AND BECAUSE OF THE LACK OF
CURRENT TRANSPORTABLE SNOW AND UNSEASONABLY WARM WATERS IN THE
BERING THAT THE BLIZZARD WATCH THERE WAS CANCELLED THIS MORNING.
THERE STILL WILL BE AREAS OF BLOWING SNOW AS STRONG WINDS KICK UP
WHATEVER DOES FALL...HOWEVER AT THIS POINT IT DOES NOT APPEAR THIS
WILL BE ENOUGH TO CREATE BLIZZARD CONDITIONS.

&&

.LONG TERM FORECAST (DAYS 3 THROUGH 7)...
AN UPPER LEVEL RIDGE BEGINS TO AMPLIFY OVER SOUTHCENTRAL
TUESDAY...THEN PUSH EAST OVER SOUTHEASTERN ALASKA AS A COMPLEX
LOW OVER THE NORTH PACIFIC TRACKS FURTHER EAST BY THE END OF THE
WEEK. MULTIPLE WAVES ASSOCIATED WITH THIS COMPLEX SYSTEM OVER THE
NORTH PACIFIC WILL TRACK INTO PARTS OF THE SOUTHERN MAINLAND
THROUGH THE END OF THE WEEK...BRINGING PRECIPITATION AND LOCALLY
GUSTY WINDS TO THE AREA. FURTHER WEST...THERE IS AN UPPER LEVEL
BLOCKING PATTERN SETTING UP WITH AN AMPLIFIED POSITIVE TILTED
RIDGE BUILDING INTO THE WESTERN ALEUTIANS/BERING SEA BY TUESDAY.
THIS RIDGE WILL EXTEND THROUGH THE WESTERN ALEUTIANS NORTHWARD
INTO THE EASTERN SIBERIAN REGION. TO THE EAST OF THE HIGH PRESSURE
SET UP OVER THE WESTERN BERING...COLDER AIR WILL FILTER DOWN OVER
THE BERING AND CENTRAL/WESTERN ALEUTIANS WEDNESDAY AND TRACK
EASTWARD OVER THE EASTERN ALEUTIANS BY FRIDAY MORNING. ANOTHER
FRONTAL SYSTEM WILL TRACK OVER THE WESTERN ALEUTIANS
FRIDAY...BRINGING IN SOME GUSTY SOUTHERLY WINDS AND MIXED
PRECIPITATION OVER THE AREA AND PERSISTING INTO THE WEEKEND.

&&


.AFC WATCHES/WARNINGS/ADVISORIES...
PUBLIC...WIND CHILL ADVISORY 155.
MARINE....GALE WARNING 129 130 131 160 165 170 175 177 179 180
          HEAVY FRZ SPRAY 121 127 129 130 131 138 139 140 141
            160 165 179 180 185
FIRE WEATHER...NONE.

&&

$$

SYNOPSIS AND MODEL DISCUSSION...MTL
SOUTHCENTRAL ALASKA...MTL
SOUTHWEST ALASKA/BERING SEA/ALEUTIANS...DEK
LONG TERM...TP




000
FXAK68 PAFC 250010
AFDAFC

SOUTHCENTRAL AND SOUTHWEST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE ANCHORAGE AK
310 PM AKST SAT JAN 24 2015

.ANALYSIS AND UPPER LEVELS...
A HIGH AMPLITUDE TROUGH IS PROGRESSING SLOWLY EASTWARD FROM SOUTHWEST
ALASKA INTO THE WESTERN GULF AND WESTERN PORTION OF SOUTHCENTRAL
ALASKA. THE TROUGH IS JUST BEGINNING TO SHOW SIGNS OF DEVELOPING A
NEGATIVE TILT...AS RISING HEIGHTS DOWNSTREAM OVER WESTERN CANADA
AND A STRENGTHENING UPPER JET BETWEEN THE TROUGH AND RIDGE CAUSE
THE TROUGH TO BEGIN TO LIFT NORTHEASTWARD. MOST OF THE ACCUMULATING
SNOW HAS ENDED FROM THE WESTERN KENAI TO ANCHORAGE AND MAT-SU.
RADAR DOES SHOW SOME WEAK RETURNS AS COLD AIR ADVECTION WITH THE
UPPER TROUGH MAINTAINS SOME VERY LOW LEVEL LIFT...RESULTING IN
VERY LIGHT SNOW OR FLURRIES. STRONG GAP WINDS HAVE DEVELOPED OVER
THE WESTERN GULF AND KODIAK ISLAND WITH THE ONSET OF COLD AIR
ADVECTION.

STRONG LIFT OUT AHEAD OF THE TROUGH COMBINED WITH UPSLOPE FLOW IS
PRODUCING MODERATE TO HEAVY PRECIPITATION OVER MUCH OF THE PRINCE
WILLIAM SOUND REGION...WITH MARGINALLY LIGHTER PRECIP OVER THE
COPPER RIVER BASIN. OF SPECIAL NOTE...PRECIPITATION STARTED THE
MORNING WITH ABOVE FREEZING TEMPERATURES AND RAIN AND SNOW. THE
INTENSITY OF THE PRECIPITATION HAS HELPED COOL THE COLUMN AND
CHANGE PRECIP TO ALL SNOW. THEREFORE...NOW EXPECT VALDEZ TO SEE A
GOOD DUMP OF SNOW OUT OF THIS STORM.

BEHIND THE TROUGH SOUTHWEST ALASKA HAS SETTLED INTO A TRUE ARCTIC
ARM MASS FOR THE FIRST TIME THIS WINTER. THE COLD SPOTTY THIS
MORNING APPEARS TO BE ANIAK WITH A TEMPERATURE OF 29 DEGREES BELOW
ZERO. UPSTREAM OF THIS AN UPPER LEVEL SHORTWAVE IS CROSSING THE
BERING SEA BRINGING SOME LIGHT SNOW TO THE REGION. MEANWHILE A
MATURE LOW OVER THE NORTHWEST PACIFIC IS TRACKING EASTWARD PUSHING
AN OCCLUDED FRONT NORTHWARD TOWARD THE ALEUTIANS. THE AIR MASS IN
PLACE RIGHT NOW IS COLD ENOUGH TO SUPPORT ALL SNOW AS
PRECIPITATION ARRIVES.

&&

.MODEL DISCUSSION...
AFTER A FEW DAYS OF DEALING WITH KEY DIFFERENCES IN MODEL GUIDANCE
THE LATEST SOLUTIONS ARE IN VERY GOOD AGREEMENT AS THINGS WIND
DOWN OVER SOUTHCENTRAL ALASKA TONIGHT INTO SUNDAY. ATTENTION
SHIFTS TO THE NORTH PACIFIC WHERE MINOR DIFFERENCES ARISE AS A
TROUGH PUSHES NORTHWARD INTO THE CENTRAL TO EASTERN BERING SEA
SUNDAY NIGHT AND MONDAY. THE BULK OF PRECIP WILL INITIALLY BE
FOCUSED OUT AHEAD OF A WARM OCCLUSION. AS THIS FRONT WEAKENS A
SERIES OF UPPER LEVEL WAVES MOVING THROUGH THE TROUGH WILL HELP
FOCUS PRECIPITATION...AND MODELS DO NOT AGREE ON STRENGTH OR
PLACEMENT OF THESE WAVES. WITH A DEEP ARCTIC AIR MASS IN PLACE
OUT AHEAD OF THE FRONT THERE WILL BE A THREAT FOR SEVERELY
REDUCED VISIBILITIES IN BLOWING SNOW FROM BRISTOL BAY TO THE
PRIBILOF ISLANDS...DEPENDING ON THE EXTENT AND INTENSITY OF THE
PRECIPITATION. FORECAST CONFIDENCE IS GENERALLY HIGH...THOUGH IT
DROPS SIGNIFICANTLY WITH DETAILS OUT WEST AS WE HEAD INTO EARLY
NEXT WEEK.

&&

.SHORT TERM FORECAST SOUTHCENTRAL ALASKA (DAYS 1 AND 2)...
AS THE UPPER TROUGH BEGINS TO LIFT NORTHEASTWARD THIS AFTERNOON
AND EVENING MODERATE TO HEAVY PRECIPITATION WILL CONTINUE FROM
EASTERN PRINCE WILLIAM SOUND TO THE PORTIONS OF THE COPPER RIVER
BASIN. THE PRIMARY SHORT-WAVE TROUGH WILL EXIT TO THE NORTHEAST
ON SUNDAY...BUT CYCLONIC FLOW WILL PERSIST ON THE SOUTH SIDE OF
AN UPPER LOW WHICH FORMS OVER INTERIOR ALASKA. THIS COMBINED WITH
COLD AIR ADVECTION WILL CAUSE SNOW SHOWERS TO LINGER IN THESE SAME
AREAS. MEANWHILE...COLD ADVECTION BEHIND THE TROUGH COMBINED WITH
UPPER LEVEL SUBSIDENCE WILL PRODUCE STRONG OUTFLOW WINDS ACROSS
THE REGION. WILL INCREASE WINDS IN THE SEWARD/RESURRECTION BAY AND
WHITTIER/PASSAGE CANAL AREAS WITH GOOD UPPER LEVEL SUPPORT AND THE
COLDEST AIR MASS OF THE ENTIRE WINTER MOVING IN.

TEMPERATURES WILL PLUMMET OVER THE NEXT 36 HOURS AS THE ARCTIC AIR
MASS SETTLES IN. WITH COLD ADVECTION CONTINUING THROUGH THE DAY
SUNDAY EXPECT TEMPERATURES TO HOLD STEADY OR CONTINUE TO FALL
DURING THE DAYTIME HOURS. THE COLD ADVECTION WILL LARGELY COME
TO AN END BY SUNDAY NIGHT ALLOWING WINDS TO DIE DOWN. THIS WILL
LIKELY BE THE COLDEST NIGHT FOR MUCH OF THE REGION. OF NOTE...WEST
ANCHORAGE (WHERE THE OFFICIAL CLIMATE STATION IS LOCATED) IS
EXPECTED TO OBSERVE THE FIRST SUB- ZERO TEMPERATURES SINCE
DECEMBER 2013.

&&

.SHORT TERM FORECAST SOUTHWEST ALASKA (DAYS 1 AND 2)...
IN THE WAKE OF THE UPPER TROUGH COLD ADVECTION WILL COME TO END
TONIGHT AND LOW LEVEL WINDS WILL CONTINUE TO SLACKEN. THUS...TONIGHT
WILL BE COLDER THAN FRIDAY NIGHT. A VERY GRADUAL MODERATION WILL
THEN BEGIN SUNDAY INTO MONDAY AS THE TROUGH OVER THE NORTH PACIFIC
LIFTS NORTHEASTWARD TOWARD SOUTHWEST ALASKA. THERE IS A TREND IN
THE GUIDANCE TOWARD MOVING PRECIP INTO BRISTOL BAY FASTER WITH
ARRIVAL SOMETIME ON MONDAY. PRESSURE GRADIENTS WILL TIGHTEN OUT
AHEAD OF A SURFACE OCCLUDED FRONT...SO WHENEVER SNOW DOES MOVE IN
THERE COULD BE SOME ISSUES WITH REDUCED VISIBILITIES IN BLOWING SNOW.

&&

.SHORT TERM FORECAST BERING SEA/ALEUTIANS (DAYS 1 AND 2)...
THE SHORT-WAVE BRINGING SNOW TO THE CENTRAL BERING WILL FLATTEN
OUT THIS AFTERNOON AND EVENING AS HEIGHTS RISE AHEAD OF THE PACIFIC
TROUGH. THUS...DON`T EXPECT ANY CLOUDS OR PRECIP TO SURVIVE BEYOND
THE EASTERN BERING SEA. THE PACIFIC TROUGH AND SURFACE STORM
SYSTEM WILL GRADUALLY PUSH PRECIP AND WARMER AIR NORTHWARD ACROSS
THE ALEUTIANS AND SOUTHERN ALASKA PENINSULA INTO THE SOUTHERN
BERING SEA. THE PRIBILOF ISLANDS WILL REMAIN SOLIDLY ON THE COLD
SIDE OF THE SURFACE OCCLUDED FRONT. THEREFORE...IF AND WHEN STEADY
SNOW REACHES THE PRIBILOFS BLIZZARD CONDITIONS ARE LIKELY. WILL
ISSUE A BLIZZARD WATCH BEGINNING MONDAY WHEN MOST MODELS INDICATE
A HIGHER POTENTIAL FOR STEADY SNOWFALL.

&&

.LONG TERM FORECAST (DAYS 3 THROUGH 7)...
THERE IS AN UPPER LEVEL BLOCKING PATTERN SETTING UP WITH AN
AMPLIFIED POSITIVE TILTED RIDGE BUILDING INTO THE WESTERN
ALEUTIANS/BERING SEA BY TUESDAY. THIS RIDGE WILL EXTEND THROUGH
THE WESTERN ALEUTIANS NORTHWARD INTO THE EASTERN SIBERIAN REGION.
IN THE SOUTHEAST ALASKA AREA...THERE IS ANOTHER AMPLIFIED RIDGE
BUILDING ALONG THE SOUTHEAST ALASKA COASTLINE. THIS RIDGE IS
EXTENDING INTO THE SOUTHCENTRAL AREA AND INTO THE BRISTOL BAY
REGION. THERE IS AN UPPER LEVEL CLOSED LOW BETWEEN THESE TWO
RIDGES LOCATED SOUTH OF THE CENTRAL/EASTERN ALEUTIANS IN THE NORTH
PACIFIC OCEAN. THE SOUTHWEST ALASKA AREA WILL HAVE OFFSHORE FLOW
WITH THE NORTHEASTERLY WINDS SETTING UP BY WEDNESDAY. THERE WILL
BE SCATTERED RAIN/SNOW SHOWERS ALONG THE SOUTHERN MAINLAND ALONG
THE EASTERN KENAI PENINSULA EXTENDING INTO KODIAK ISLAND. THE
SHORTWAVES WILL ROTATE AROUND THE COMPLEX LOW IN THE NORTH PACIFIC
AND PUSH THROUGH THE EASTERN ALEUTIANS. THE TEMPERATURES ALONG THE
CENTRAL TO EASTERN ALEUTIANS EXTENDING TO THE WESTERN GULF AND THE
COASTLINES WILL SEE A WARMING TREND. THIS WILL COINCIDE WITH THE
COMPLEX NORTH PACIFIC LOW AS IT GRADUALLY MOVES NORTH TOWARDS
KODIAK ISLAND BY WEDNESDAY WITH CONTINUED SOUTHERLY FLOW IN THE
GULF HEADING INTO THE WEEKEND.

&&


.AFC WATCHES/WARNINGS/ADVISORIES...
PUBLIC...BLIZZARD WATCH 195. SNOW ADVISORY 141.
MARINE...GALE WARNING 129 130 131 170 179.
         HEAVY FRZ SPRAY 121 126 127 128 129 130 131 138
            139 140 141 150 160 165 180 185.
FIRE WEATHER...NONE.

&&

$$

SYNOPSIS AND MODEL DISCUSSION...SB
SOUTHCENTRAL ALASKA...SB
SOUTHWEST ALASKA/BERING SEA/ALEUTIANS...SB
LONG TERM...PD




000
FXAK68 PAFC 250010
AFDAFC

SOUTHCENTRAL AND SOUTHWEST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE ANCHORAGE AK
310 PM AKST SAT JAN 24 2015

.ANALYSIS AND UPPER LEVELS...
A HIGH AMPLITUDE TROUGH IS PROGRESSING SLOWLY EASTWARD FROM SOUTHWEST
ALASKA INTO THE WESTERN GULF AND WESTERN PORTION OF SOUTHCENTRAL
ALASKA. THE TROUGH IS JUST BEGINNING TO SHOW SIGNS OF DEVELOPING A
NEGATIVE TILT...AS RISING HEIGHTS DOWNSTREAM OVER WESTERN CANADA
AND A STRENGTHENING UPPER JET BETWEEN THE TROUGH AND RIDGE CAUSE
THE TROUGH TO BEGIN TO LIFT NORTHEASTWARD. MOST OF THE ACCUMULATING
SNOW HAS ENDED FROM THE WESTERN KENAI TO ANCHORAGE AND MAT-SU.
RADAR DOES SHOW SOME WEAK RETURNS AS COLD AIR ADVECTION WITH THE
UPPER TROUGH MAINTAINS SOME VERY LOW LEVEL LIFT...RESULTING IN
VERY LIGHT SNOW OR FLURRIES. STRONG GAP WINDS HAVE DEVELOPED OVER
THE WESTERN GULF AND KODIAK ISLAND WITH THE ONSET OF COLD AIR
ADVECTION.

STRONG LIFT OUT AHEAD OF THE TROUGH COMBINED WITH UPSLOPE FLOW IS
PRODUCING MODERATE TO HEAVY PRECIPITATION OVER MUCH OF THE PRINCE
WILLIAM SOUND REGION...WITH MARGINALLY LIGHTER PRECIP OVER THE
COPPER RIVER BASIN. OF SPECIAL NOTE...PRECIPITATION STARTED THE
MORNING WITH ABOVE FREEZING TEMPERATURES AND RAIN AND SNOW. THE
INTENSITY OF THE PRECIPITATION HAS HELPED COOL THE COLUMN AND
CHANGE PRECIP TO ALL SNOW. THEREFORE...NOW EXPECT VALDEZ TO SEE A
GOOD DUMP OF SNOW OUT OF THIS STORM.

BEHIND THE TROUGH SOUTHWEST ALASKA HAS SETTLED INTO A TRUE ARCTIC
ARM MASS FOR THE FIRST TIME THIS WINTER. THE COLD SPOTTY THIS
MORNING APPEARS TO BE ANIAK WITH A TEMPERATURE OF 29 DEGREES BELOW
ZERO. UPSTREAM OF THIS AN UPPER LEVEL SHORTWAVE IS CROSSING THE
BERING SEA BRINGING SOME LIGHT SNOW TO THE REGION. MEANWHILE A
MATURE LOW OVER THE NORTHWEST PACIFIC IS TRACKING EASTWARD PUSHING
AN OCCLUDED FRONT NORTHWARD TOWARD THE ALEUTIANS. THE AIR MASS IN
PLACE RIGHT NOW IS COLD ENOUGH TO SUPPORT ALL SNOW AS
PRECIPITATION ARRIVES.

&&

.MODEL DISCUSSION...
AFTER A FEW DAYS OF DEALING WITH KEY DIFFERENCES IN MODEL GUIDANCE
THE LATEST SOLUTIONS ARE IN VERY GOOD AGREEMENT AS THINGS WIND
DOWN OVER SOUTHCENTRAL ALASKA TONIGHT INTO SUNDAY. ATTENTION
SHIFTS TO THE NORTH PACIFIC WHERE MINOR DIFFERENCES ARISE AS A
TROUGH PUSHES NORTHWARD INTO THE CENTRAL TO EASTERN BERING SEA
SUNDAY NIGHT AND MONDAY. THE BULK OF PRECIP WILL INITIALLY BE
FOCUSED OUT AHEAD OF A WARM OCCLUSION. AS THIS FRONT WEAKENS A
SERIES OF UPPER LEVEL WAVES MOVING THROUGH THE TROUGH WILL HELP
FOCUS PRECIPITATION...AND MODELS DO NOT AGREE ON STRENGTH OR
PLACEMENT OF THESE WAVES. WITH A DEEP ARCTIC AIR MASS IN PLACE
OUT AHEAD OF THE FRONT THERE WILL BE A THREAT FOR SEVERELY
REDUCED VISIBILITIES IN BLOWING SNOW FROM BRISTOL BAY TO THE
PRIBILOF ISLANDS...DEPENDING ON THE EXTENT AND INTENSITY OF THE
PRECIPITATION. FORECAST CONFIDENCE IS GENERALLY HIGH...THOUGH IT
DROPS SIGNIFICANTLY WITH DETAILS OUT WEST AS WE HEAD INTO EARLY
NEXT WEEK.

&&

.SHORT TERM FORECAST SOUTHCENTRAL ALASKA (DAYS 1 AND 2)...
AS THE UPPER TROUGH BEGINS TO LIFT NORTHEASTWARD THIS AFTERNOON
AND EVENING MODERATE TO HEAVY PRECIPITATION WILL CONTINUE FROM
EASTERN PRINCE WILLIAM SOUND TO THE PORTIONS OF THE COPPER RIVER
BASIN. THE PRIMARY SHORT-WAVE TROUGH WILL EXIT TO THE NORTHEAST
ON SUNDAY...BUT CYCLONIC FLOW WILL PERSIST ON THE SOUTH SIDE OF
AN UPPER LOW WHICH FORMS OVER INTERIOR ALASKA. THIS COMBINED WITH
COLD AIR ADVECTION WILL CAUSE SNOW SHOWERS TO LINGER IN THESE SAME
AREAS. MEANWHILE...COLD ADVECTION BEHIND THE TROUGH COMBINED WITH
UPPER LEVEL SUBSIDENCE WILL PRODUCE STRONG OUTFLOW WINDS ACROSS
THE REGION. WILL INCREASE WINDS IN THE SEWARD/RESURRECTION BAY AND
WHITTIER/PASSAGE CANAL AREAS WITH GOOD UPPER LEVEL SUPPORT AND THE
COLDEST AIR MASS OF THE ENTIRE WINTER MOVING IN.

TEMPERATURES WILL PLUMMET OVER THE NEXT 36 HOURS AS THE ARCTIC AIR
MASS SETTLES IN. WITH COLD ADVECTION CONTINUING THROUGH THE DAY
SUNDAY EXPECT TEMPERATURES TO HOLD STEADY OR CONTINUE TO FALL
DURING THE DAYTIME HOURS. THE COLD ADVECTION WILL LARGELY COME
TO AN END BY SUNDAY NIGHT ALLOWING WINDS TO DIE DOWN. THIS WILL
LIKELY BE THE COLDEST NIGHT FOR MUCH OF THE REGION. OF NOTE...WEST
ANCHORAGE (WHERE THE OFFICIAL CLIMATE STATION IS LOCATED) IS
EXPECTED TO OBSERVE THE FIRST SUB- ZERO TEMPERATURES SINCE
DECEMBER 2013.

&&

.SHORT TERM FORECAST SOUTHWEST ALASKA (DAYS 1 AND 2)...
IN THE WAKE OF THE UPPER TROUGH COLD ADVECTION WILL COME TO END
TONIGHT AND LOW LEVEL WINDS WILL CONTINUE TO SLACKEN. THUS...TONIGHT
WILL BE COLDER THAN FRIDAY NIGHT. A VERY GRADUAL MODERATION WILL
THEN BEGIN SUNDAY INTO MONDAY AS THE TROUGH OVER THE NORTH PACIFIC
LIFTS NORTHEASTWARD TOWARD SOUTHWEST ALASKA. THERE IS A TREND IN
THE GUIDANCE TOWARD MOVING PRECIP INTO BRISTOL BAY FASTER WITH
ARRIVAL SOMETIME ON MONDAY. PRESSURE GRADIENTS WILL TIGHTEN OUT
AHEAD OF A SURFACE OCCLUDED FRONT...SO WHENEVER SNOW DOES MOVE IN
THERE COULD BE SOME ISSUES WITH REDUCED VISIBILITIES IN BLOWING SNOW.

&&

.SHORT TERM FORECAST BERING SEA/ALEUTIANS (DAYS 1 AND 2)...
THE SHORT-WAVE BRINGING SNOW TO THE CENTRAL BERING WILL FLATTEN
OUT THIS AFTERNOON AND EVENING AS HEIGHTS RISE AHEAD OF THE PACIFIC
TROUGH. THUS...DON`T EXPECT ANY CLOUDS OR PRECIP TO SURVIVE BEYOND
THE EASTERN BERING SEA. THE PACIFIC TROUGH AND SURFACE STORM
SYSTEM WILL GRADUALLY PUSH PRECIP AND WARMER AIR NORTHWARD ACROSS
THE ALEUTIANS AND SOUTHERN ALASKA PENINSULA INTO THE SOUTHERN
BERING SEA. THE PRIBILOF ISLANDS WILL REMAIN SOLIDLY ON THE COLD
SIDE OF THE SURFACE OCCLUDED FRONT. THEREFORE...IF AND WHEN STEADY
SNOW REACHES THE PRIBILOFS BLIZZARD CONDITIONS ARE LIKELY. WILL
ISSUE A BLIZZARD WATCH BEGINNING MONDAY WHEN MOST MODELS INDICATE
A HIGHER POTENTIAL FOR STEADY SNOWFALL.

&&

.LONG TERM FORECAST (DAYS 3 THROUGH 7)...
THERE IS AN UPPER LEVEL BLOCKING PATTERN SETTING UP WITH AN
AMPLIFIED POSITIVE TILTED RIDGE BUILDING INTO THE WESTERN
ALEUTIANS/BERING SEA BY TUESDAY. THIS RIDGE WILL EXTEND THROUGH
THE WESTERN ALEUTIANS NORTHWARD INTO THE EASTERN SIBERIAN REGION.
IN THE SOUTHEAST ALASKA AREA...THERE IS ANOTHER AMPLIFIED RIDGE
BUILDING ALONG THE SOUTHEAST ALASKA COASTLINE. THIS RIDGE IS
EXTENDING INTO THE SOUTHCENTRAL AREA AND INTO THE BRISTOL BAY
REGION. THERE IS AN UPPER LEVEL CLOSED LOW BETWEEN THESE TWO
RIDGES LOCATED SOUTH OF THE CENTRAL/EASTERN ALEUTIANS IN THE NORTH
PACIFIC OCEAN. THE SOUTHWEST ALASKA AREA WILL HAVE OFFSHORE FLOW
WITH THE NORTHEASTERLY WINDS SETTING UP BY WEDNESDAY. THERE WILL
BE SCATTERED RAIN/SNOW SHOWERS ALONG THE SOUTHERN MAINLAND ALONG
THE EASTERN KENAI PENINSULA EXTENDING INTO KODIAK ISLAND. THE
SHORTWAVES WILL ROTATE AROUND THE COMPLEX LOW IN THE NORTH PACIFIC
AND PUSH THROUGH THE EASTERN ALEUTIANS. THE TEMPERATURES ALONG THE
CENTRAL TO EASTERN ALEUTIANS EXTENDING TO THE WESTERN GULF AND THE
COASTLINES WILL SEE A WARMING TREND. THIS WILL COINCIDE WITH THE
COMPLEX NORTH PACIFIC LOW AS IT GRADUALLY MOVES NORTH TOWARDS
KODIAK ISLAND BY WEDNESDAY WITH CONTINUED SOUTHERLY FLOW IN THE
GULF HEADING INTO THE WEEKEND.

&&


.AFC WATCHES/WARNINGS/ADVISORIES...
PUBLIC...BLIZZARD WATCH 195. SNOW ADVISORY 141.
MARINE...GALE WARNING 129 130 131 170 179.
         HEAVY FRZ SPRAY 121 126 127 128 129 130 131 138
            139 140 141 150 160 165 180 185.
FIRE WEATHER...NONE.

&&

$$

SYNOPSIS AND MODEL DISCUSSION...SB
SOUTHCENTRAL ALASKA...SB
SOUTHWEST ALASKA/BERING SEA/ALEUTIANS...SB
LONG TERM...PD





000
FXAK68 PAFC 241417
AFDAFC

SOUTHCENTRAL AND SOUTHWEST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE ANCHORAGE AK
517 AM AKST SAT JAN 24 2015

.ANALYSIS AND UPPER LEVELS...
A BROAD TROUGH EXTENDS SOUTHWARD FROM NORTHERN ALASKA SOUTHWARD
THROUGH THE ALASKA RANGE WHERE DRY AIR IS CURRENTLY PUSHING
EASTWARD OVER COOK INLET. AHEAD OF THE TROUGH SOUTHWESTERLY FLOW
STREAMS FROM THE GULF THROUGH THE COPPER RIVER BASIN.  DEEP LAYER
MOISTURE IS QUICKLY MOVING TO THE EAST AS DRY AIR FILTERS IN FROM
THE WEST.

&&

.MODEL DISCUSSION...
GUIDANCE HAS SHOWN THE FULL ENVELOPE OF SOLUTIONS FOR THE LAST
COUPLE DAYS RANGING FROM SNOW AMOUNTS OF EPIC PROPORTIONS TO VERY
MINOR ACCUMULATIONS. THE RECENT TREND HAS BEEN WHISKING THE DEEP
LAYER MOISTURE TO THE EAST DESPITE MOST OF THE COOK INLET AREA
REMAINING UNDER FAVORABLE DYNAMICS...WITH THE UPPER TROUGH STILL
TO THE WEST THROUGH THE AFTERNOON. OTHERWISE GUIDANCE IN GOOD
AGREEMENT WITH THE REMAINDER OF THIS SYSTEM THROUGH THE WEEKEND.
CONSENSUS SAYS A PIECE OF ENERGY WILL MIGRATE FROM THE NORTH TO
THE GULF AND JOIN WITH THE EXISTING TROUGH...MAINLY AFFECTING THE
PRINCE WILLIAM SOUND AREA AS WELL AS COPPER RIVER BASIN.

&&

.SHORT TERM FORECAST SOUTHCENTRAL ALASKA (DAY 1 AND DAY 2)...
THE THREAT FOR SNOW TODAY WILL MAINLY BE ALONG THE
CHUGACH/TALKEETNA MOUNTAINS AS A DISTURBANCE MOVES SOME MOISTURE
INTO PRINCE WILLIAM SOUND. TEMPERATURES WILL HOLD STEADY OR FALL
THROUGHOUT THE DAY AS COLD AIR CONTINUES TO INFILTRATE THROUGH THE
ALASKA RANGE. MOST OF THE ACTION TODAY WILL BE ALONG THE NORTH
GULF COAST GULF COAST WITH CONTINUED ONSHORE FLOW AS WELL AS THE
COPPER BASIN WHICH WILL GET BOTH THE INCOMING DISTURBANCE AND THE
CURRENT TROUGH OVERHEAD. SUNDAY TRANSITIONS INTO A COLD OUTFLOW
PATTERN FOR MUCH OF THE SOUTHCENTRAL WITH SOME OF THE COLDEST
TEMPERATURES OF THE SEASON IN MOST AREAS AND GUSTY WINDS ALONG THE
GULF COAST.

&&

.SHORT TERM FORECAST SOUTHWEST ALASKA (DAY 1 AND DAY 2)...
CLEAR SKIES THROUGHOUT THE SOUTHWEST MAINLAND WILL ALLOW FOR SOME
OF THE COLDEST OVERNIGHT LOWS OF THE SEASON TO OCCUR OVER THE NEXT
TWO NIGHTS. SOME GUSTY NORTHERLY WINDS WILL ALSO CONTINUE ALONG
THE KUSKOKWIM DELTA COAST INTO THE WESTERN CAPES...CREATING VERY
COLD WIND CHILLS DURING THE OVERNIGHT HOURS...BUT NOT QUITE TO
ADVISORY CRITERIA. THIS COLD TEMPERATURES AND GUSTY WINDS ALONG
THE COAST WILL CONTINUE THROUGH THE WEEKEND BEFORE BEGINNING TO
WARM ON SUNDAY NIGHT AS AN ALEUTIAN FRONT APPROACHES THE ALASKA
PENINSULA.

&&

.SHORT TERM FORECAST BERING SEA/ALEUTIANS (DAY 1 AND DAY 2)...
AN UPPER LEVEL SHORTWAVE TRAVERSING THROUGH THE CENTRAL BERING
WILL BRING SNOW SHOWERS FROM THE PRIBILOFS INTO THE EASTERN
ALEUTIANS TODAY...WITH LIGHT ACCUMULATIONS EXPECTED. A NORTH
PACIFIC LOW WILL THEN BEGIN MOVING INTO THE WESTERN ALEUTIANS BY
THIS EVENING...BRINGING RAIN/SNOW AND GALE FORCE WINDS THAT WILL
SPREAD INTO THE CENTRAL ALEUTIANS FOR SUNDAY.

&&

.LONG TERM FORECAST (DAYS 3 THROUGH 7)...
A BROAD UPPER LEVEL RIDGE WILL BEGIN TO SET UP OVER THE SOUTHERN
MAINLAND MONDAY MORNING...AND CONTINUE TO AMPLIFY AND PUSH
EASTWARD (OVER SOUTHCENTRAL MAINLAND) THROUGH THE END OF THE WEEK
AS IT INTERACTS WITH A COMPLEX LOW IN THE NORTH PACIFIC. MULTIPLE
WAVES ASSOCIATED WITH THIS COMPLEX SYSTEM WILL TRACK THROUGH THE
SOUTHWEST MAINLAND AND GULF COAST THROUGH THE END OF THE
WEEK...BRINGING WAVE AFTER WAVE OF PRECIPITATION AND LOCALLY GUSTY
WINDS TO THE AREA. OVER THE BERING...A SPLIT PATTERN ALOFT SHIFTS
SLOWLY EAST WITH A RIDGE OVER THE BERING STRAIT AND A CLOSED LOW
SOUTH OF THE ALEUTIANS. THE UPPER RIDGE DRIVES A COLDER AIR MASS
SOUTH ACROSS THE BERING THROUGH MID WEEK. SCATTERED SNOW SHOWERS
ACROSS THE BERING WILL MIX WITH WITH RAIN ALONG THE ALEUTIANS AS
THESE TO SYSTEMS INTERACT WITH EACH OTHER. AS THE SYSTEM OVER THE
NORTH PACIFIC TRACKS EASTWARD...COLDER NORTHERLY FLOW WILL BEGIN
TO FILTER DOWN ON THE BACKSIDE OF THE LOW AND OVER THE WESTERN
ALEUTIANS. SCATTERED SNOW SHOWERS ARE POSSIBLE OVER THE BERING AND
ALEUTIANS DURING THIS TIME...AS THE COLDER AIR MOVING OVER THE
WARMER SEA SURFACE CAN PRODUCE CONVECTIVE SHOWERS. THIS COLDER AIR
AND SHOWERY CONDITIONS WILL TRACK THROUGH THE CENTRAL AND EASTERN
ALEUTIANS BY THE END OF THE WEEK...JUST IN TIME FOR ANOTHER
FRONTAL SYSTEM TO TRACK INTO THE WESTERN ALEUTIANS.

&&


.AFC WATCHES/WARNINGS/ADVISORIES...
PUBLIC...WINTER WEATHER ADVISORY 111 141.
MARINE...GALES 130 131 150
         HEAVY FREEZING SPRAY 121 129 130 131 138 150 160 180 185
FIRE WEATHER...NONE.

&&

$$

SYNOPSIS AND MODEL DISCUSSION...MTL
SOUTHCENTRAL ALASKA...MTL
SOUTHWEST ALASKA/BERING SEA/ALEUTIANS...DEK
LONG TERM...TP





000
FXAK68 PAFC 241417
AFDAFC

SOUTHCENTRAL AND SOUTHWEST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE ANCHORAGE AK
517 AM AKST SAT JAN 24 2015

.ANALYSIS AND UPPER LEVELS...
A BROAD TROUGH EXTENDS SOUTHWARD FROM NORTHERN ALASKA SOUTHWARD
THROUGH THE ALASKA RANGE WHERE DRY AIR IS CURRENTLY PUSHING
EASTWARD OVER COOK INLET. AHEAD OF THE TROUGH SOUTHWESTERLY FLOW
STREAMS FROM THE GULF THROUGH THE COPPER RIVER BASIN.  DEEP LAYER
MOISTURE IS QUICKLY MOVING TO THE EAST AS DRY AIR FILTERS IN FROM
THE WEST.

&&

.MODEL DISCUSSION...
GUIDANCE HAS SHOWN THE FULL ENVELOPE OF SOLUTIONS FOR THE LAST
COUPLE DAYS RANGING FROM SNOW AMOUNTS OF EPIC PROPORTIONS TO VERY
MINOR ACCUMULATIONS. THE RECENT TREND HAS BEEN WHISKING THE DEEP
LAYER MOISTURE TO THE EAST DESPITE MOST OF THE COOK INLET AREA
REMAINING UNDER FAVORABLE DYNAMICS...WITH THE UPPER TROUGH STILL
TO THE WEST THROUGH THE AFTERNOON. OTHERWISE GUIDANCE IN GOOD
AGREEMENT WITH THE REMAINDER OF THIS SYSTEM THROUGH THE WEEKEND.
CONSENSUS SAYS A PIECE OF ENERGY WILL MIGRATE FROM THE NORTH TO
THE GULF AND JOIN WITH THE EXISTING TROUGH...MAINLY AFFECTING THE
PRINCE WILLIAM SOUND AREA AS WELL AS COPPER RIVER BASIN.

&&

.SHORT TERM FORECAST SOUTHCENTRAL ALASKA (DAY 1 AND DAY 2)...
THE THREAT FOR SNOW TODAY WILL MAINLY BE ALONG THE
CHUGACH/TALKEETNA MOUNTAINS AS A DISTURBANCE MOVES SOME MOISTURE
INTO PRINCE WILLIAM SOUND. TEMPERATURES WILL HOLD STEADY OR FALL
THROUGHOUT THE DAY AS COLD AIR CONTINUES TO INFILTRATE THROUGH THE
ALASKA RANGE. MOST OF THE ACTION TODAY WILL BE ALONG THE NORTH
GULF COAST GULF COAST WITH CONTINUED ONSHORE FLOW AS WELL AS THE
COPPER BASIN WHICH WILL GET BOTH THE INCOMING DISTURBANCE AND THE
CURRENT TROUGH OVERHEAD. SUNDAY TRANSITIONS INTO A COLD OUTFLOW
PATTERN FOR MUCH OF THE SOUTHCENTRAL WITH SOME OF THE COLDEST
TEMPERATURES OF THE SEASON IN MOST AREAS AND GUSTY WINDS ALONG THE
GULF COAST.

&&

.SHORT TERM FORECAST SOUTHWEST ALASKA (DAY 1 AND DAY 2)...
CLEAR SKIES THROUGHOUT THE SOUTHWEST MAINLAND WILL ALLOW FOR SOME
OF THE COLDEST OVERNIGHT LOWS OF THE SEASON TO OCCUR OVER THE NEXT
TWO NIGHTS. SOME GUSTY NORTHERLY WINDS WILL ALSO CONTINUE ALONG
THE KUSKOKWIM DELTA COAST INTO THE WESTERN CAPES...CREATING VERY
COLD WIND CHILLS DURING THE OVERNIGHT HOURS...BUT NOT QUITE TO
ADVISORY CRITERIA. THIS COLD TEMPERATURES AND GUSTY WINDS ALONG
THE COAST WILL CONTINUE THROUGH THE WEEKEND BEFORE BEGINNING TO
WARM ON SUNDAY NIGHT AS AN ALEUTIAN FRONT APPROACHES THE ALASKA
PENINSULA.

&&

.SHORT TERM FORECAST BERING SEA/ALEUTIANS (DAY 1 AND DAY 2)...
AN UPPER LEVEL SHORTWAVE TRAVERSING THROUGH THE CENTRAL BERING
WILL BRING SNOW SHOWERS FROM THE PRIBILOFS INTO THE EASTERN
ALEUTIANS TODAY...WITH LIGHT ACCUMULATIONS EXPECTED. A NORTH
PACIFIC LOW WILL THEN BEGIN MOVING INTO THE WESTERN ALEUTIANS BY
THIS EVENING...BRINGING RAIN/SNOW AND GALE FORCE WINDS THAT WILL
SPREAD INTO THE CENTRAL ALEUTIANS FOR SUNDAY.

&&

.LONG TERM FORECAST (DAYS 3 THROUGH 7)...
A BROAD UPPER LEVEL RIDGE WILL BEGIN TO SET UP OVER THE SOUTHERN
MAINLAND MONDAY MORNING...AND CONTINUE TO AMPLIFY AND PUSH
EASTWARD (OVER SOUTHCENTRAL MAINLAND) THROUGH THE END OF THE WEEK
AS IT INTERACTS WITH A COMPLEX LOW IN THE NORTH PACIFIC. MULTIPLE
WAVES ASSOCIATED WITH THIS COMPLEX SYSTEM WILL TRACK THROUGH THE
SOUTHWEST MAINLAND AND GULF COAST THROUGH THE END OF THE
WEEK...BRINGING WAVE AFTER WAVE OF PRECIPITATION AND LOCALLY GUSTY
WINDS TO THE AREA. OVER THE BERING...A SPLIT PATTERN ALOFT SHIFTS
SLOWLY EAST WITH A RIDGE OVER THE BERING STRAIT AND A CLOSED LOW
SOUTH OF THE ALEUTIANS. THE UPPER RIDGE DRIVES A COLDER AIR MASS
SOUTH ACROSS THE BERING THROUGH MID WEEK. SCATTERED SNOW SHOWERS
ACROSS THE BERING WILL MIX WITH WITH RAIN ALONG THE ALEUTIANS AS
THESE TO SYSTEMS INTERACT WITH EACH OTHER. AS THE SYSTEM OVER THE
NORTH PACIFIC TRACKS EASTWARD...COLDER NORTHERLY FLOW WILL BEGIN
TO FILTER DOWN ON THE BACKSIDE OF THE LOW AND OVER THE WESTERN
ALEUTIANS. SCATTERED SNOW SHOWERS ARE POSSIBLE OVER THE BERING AND
ALEUTIANS DURING THIS TIME...AS THE COLDER AIR MOVING OVER THE
WARMER SEA SURFACE CAN PRODUCE CONVECTIVE SHOWERS. THIS COLDER AIR
AND SHOWERY CONDITIONS WILL TRACK THROUGH THE CENTRAL AND EASTERN
ALEUTIANS BY THE END OF THE WEEK...JUST IN TIME FOR ANOTHER
FRONTAL SYSTEM TO TRACK INTO THE WESTERN ALEUTIANS.

&&


.AFC WATCHES/WARNINGS/ADVISORIES...
PUBLIC...WINTER WEATHER ADVISORY 111 141.
MARINE...GALES 130 131 150
         HEAVY FREEZING SPRAY 121 129 130 131 138 150 160 180 185
FIRE WEATHER...NONE.

&&

$$

SYNOPSIS AND MODEL DISCUSSION...MTL
SOUTHCENTRAL ALASKA...MTL
SOUTHWEST ALASKA/BERING SEA/ALEUTIANS...DEK
LONG TERM...TP




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