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000
FXAK68 PAFC 241337
AFDAFC

SOUTHCENTRAL AND SOUTHWEST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE ANCHORAGE AK
437 AM AKST MON NOV 24 2014

.ANALYSIS AND UPPER LEVELS...
A 997 MB LOW CURRENTLY 110 MILES SOUTHWEST OF SITKINAK ISLAND IS
SLOWLY MOVING IN THE GENERAL DIRECTION OF THE GULF OF
ALASKA...WEAKENING RAPIDLY AS STRONG HIGH PRESSURE RIDGING
CONTINUES TO MOVE RAPIDLY NORTH AND EAST TOWARD THE MAINLAND FROM
THE CENTRAL BERING SEA. THIS RIDGING IS GETTING AMPLIFIED IN PART
DUE TO A SEASONABLY STRONG AND QUASI-STATIONARY LOW PRESSURE
SYSTEM SITTING APPROXIMATELY HALFWAY BETWEEN ATTU AND THE
KAMCHATKA PENINSULA OF RUSSIA. NUMEROUS VIGOROUS DISTURBANCES ARE
ROTATING AROUND THE BROAD CYCLONIC CIRCULATION WITH A VERY ACTIVE
UPPER LEVEL JET STREAM.

&&

.MODEL DISCUSSION ...
MODELS ARE HANDLING THE LARGE-SCALE SYNOPTIC ENVIRONMENT WELL IN
DEVELOPING SIGNIFICANT UPPER LEVEL RIDGING OVER THE MAINLAND OF
ALASKA TUESDAY THROUGH THURSDAY. MOST OF THE SIGNIFICANT
DISCREPANCIES IN THE NEXT 2 TO 3 DAYS LIES WITH THE ACTIVE JET
STREAK PATTERN THAT WILL CONTINUE TO EVOLVE TO THE SOUTH OF THE
BROAD LOW OVER THE FAR WESTERN BERING AS IT CONTINUES TO SIT AND
SPIN THROUGH THE EARLY TO MID-WEEK PERIOD. MODELS DEPICT A PAIR OF
LOWS MOVING NORTH AND EAST ACROSS THE ALEUTIANS AND INTO THE
BERING SEA TUESDAY INTO THURSDAY BEFORE MERGING INTO THE PARENT
LOW CENTER. THE EUROPEAN MODEL WAS PREFERRED SLIGHTLY OVER THE GFS
AND CANADIAN MODELS FOR THIS FORECAST PACKAGE.

&&

.SHORT TERM FORECAST SOUTHCENTRAL ALASKA (DAYS 1 THROUGH 2)...
THE STAGNANT PATTERN OF THE PAST FEW DAYS WILL BEGIN TO CHANGE
TODAY AS AMPLIFYING UPSTREAM FLOW OVER THE NORTH CENTRAL PACIFIC
AND BERING SEA HELPS KICK THE LOW ALONG THE ALASKA PENINSULA
EASTWARD ACROSS THE GULF. AS A RESULT THE MEAN FLOW IN THE LOW
TO MID LEVELS OVER SOUTHCENTRAL ALASKA WILL GRADUALLY VEER FROM
SOUTH-SOUTHEAST TO SOUTHWEST OVER THE NEXT 12 HOURS. THIS CHANGE
IN FLOW WILL START TO BREAK UP THE PERSISTENT SHOWER ACTIVITY IN
THE PRINCE WILLIAM SOUND REGION.

MEANWHILE THE DEVELOPMENT OF UPSLOPE FLOW ON THE WEST SIDE OF THE
CHUGACH AND TALKEETNA MOUNTAINS COMBINED WITH WEAK VERTICAL MOTION
FROM UPPER LEVEL DISTURBANCES EMBEDDED IN THE FLOW WILL DEEPEN
MOISTURE FROM ANCHORAGE UP TO THE MATANUSKA VALLEY AND EASTERN
SUSITNA VALLEY...PLACES WHICH HAVE REMAINED QUITE DRY UNDER THE
CURRENT FLOW. ASIDE FROM AN INCREASE IN CLOUDS IN THESE
LOCATIONS...THIS WILL SET THE STAGE FOR A POSSIBLE LIGHT SNOW
EVENT TUESDAY/TUESDAY NIGHT AS AN UPPER TROUGH MOVES THROUGH. THE
TROUGH WILL BE WEAKENING DUE TO INCREASED ANTICYCLONIC FLOW WITH
A BUILDING UPSTREAM RIDGE. THERE IS A MODEL CONSENSUS THAT THE
BEST VERTICAL MOTION WILL BE OVER THE NORTHERN TIER OF THE SUSITNA
VALLEY. SINCE NUMERICAL GUIDANCE HAS JUST RECENTLY LOCKED IN TO
THIS FEATURE AND IT IS ON THE WEAK SIDE WILL GENERALLY STICK WITH
CHANCE POPS FOR NOW.

A STRONG RIDGE WILL BUILD IN FROM THE WEST TUESDAY NIGHT BRINGING
IDEAL CONDITIONS FOR RADIATIONAL COOLING...SO HAVE TRENDED
DOWNWARD WITH NIGHT-TIME TEMPERATURES. STABLE CONDITIONS AND
LIGHT WINDS AT THE SURFACE ALSO FAVORS FORMATION OF FOG IN COOK
INLET. THIS ALWAYS MAKES FOR CHALLENGING SKY AND TEMPERATURE
FORECASTS. FARTHER EAST WEAK COLD ADVECTION IN THE WAKE OF THE
UPPER TROUGH COMBINED WITH TIGHTENING PRESSURE GRADIENTS AS A
SURFACE HIGH BUILDS OVER THE INTERIOR WILL LEAD TO WEAK OUTFLOW
WINDS (FOR THIS TIME OF YEAR) ALONG THE NORTH GULF COAST/PRINCE
WILLIAM SOUND.

&&

.SHORT TERM FORECAST SOUTHWEST ALASKA (TONIGHT THROUGH TUESDAY
NIGHT)...
A FEW SNOW SHOWERS WILL CONTINUE TO DEVELOP ACROSS SOUTHWEST
ALASKA ALONG THE BACKSIDE OF LOW PRESSURE SYSTEM AS IT MOVES EAST.
OTHERWISE DRY COOL CONDITIONS PERSIST THROUGH TUESDAY NIGHT. A
WARM FRONT APPROACHES THE WEST COAST ALONG THE KUSKOKWIM DELTA
TUESDAY NIGHT BRINGING A CHANCE FOR SNOW.

&&

.SHORT TERM FORECAST BERING SEA/ALEUTIANS (TONIGHT THROUGH TUESDAY
NIGHT)...
A FRONT HAS PUSHED INTO THE WESTERN ALEUTIANS BRINGING GUSTY GALE
WINDS AND RAIN. THE FRONTAL BOUNDARY PUSHES SLOWLY INTO THE
CENTRAL ALEUTIANS AND NORTHERN BERING TONIGHT. COLD AIR ADVECTION
BEHIND THE FRONT WILL BRING MIXED SHOWERY PRECIPITATION BACK INTO
THE WESTERN ALEUTIANS TONIGHT. GUSTY WINDS WILL BRIEFLY DIMINISH
BEHIND THE FRONT AS THE PARENT LOW STEERS THE NEXT TWO LOW CENTERS
TOWARD THE WESTERN AND EASTERN ALEUTIANS TUESDAY NIGHT.



&&

.LONG TERM FORECAST (DAYS 3 THROUGH 7)...

MODELS ARE IN GOOD AGREEMENT THAT A HIGH AMPLITUDE BLOCKING UPPER
RIDGE WILL DEVELOP BY WED OVER MAINLAND AK AND THE GULF...WITH A
CUT-OFF LOW EMBEDDED IN A TROUGH OVER THE BERING. THE RIDGE WILL
REMAIN IN PLACE INTO FRI WHEN A MAJOR PATTERN CHANGE OCCURS. THE
BERING CUT-OFF LOW CUTS THROUGH THE RIDGE...TRANSFORMING THE HIGH
AMPLITUDE PATTERN INTO ONE WITH SHORTER WAVES MOVING PROGRESSIVELY
ACROSS THE FORECAST AREA. AS IS TYPICAL WITH WAVES MOVING THROUGH
RELATIVELY ZONAL FLOW...TIMING IS THE MAIN ISSUE SAT THROUGH MON.

THERE IS FAIRLY HIGH CONFIDENCE THAT SOUTHCENTRAL WILL REMAIN DRY
BENEATH THE RIDGE INTO THE WEEKEND...ALTHOUGH RAIN AND SNOW MAY
AFFECT THE COAST BY SUN. THE FORECAST FOR THE BERING IS OF LOWER
CONFIDENCE DUE TO TIMING UNCERTAINTY. IT UTILIZES A BLEND OF THE
GFS...EC..AND WPC GUIDANCE...AND HAS THE SURFACE REFLECTION OF THE
UPPER BERING LOW SLOWLY WEAKENING AS IT MOVES THROUGH THE BERING
WED THROUGH FRI. THIS LOW WILL BRING RAIN WITH GALES AND THEN
SMALL CRAFT WINDS TO THE BERING AND ALEUTIANS BEFORE IT CROSSES
THE EASTERN ALEUTIANS AND DISSIPATES IN THE NORTH PACIFIC ON SAT.
A NEW LOW FROM JAPAN WILL APPROACH THE WESTERN ALEUTIANS SAT AND
SUN AND WILL BRING MORE RAIN AND WIND TO THE CHAIN FOR THE
WEEKEND.

&&


.AFC WATCHES/WARNINGS/ADVISORIES...
PUBLIC...NONE.
MARINE...GALES 173 174 175 176 177 178 185.
FIRE WEATHER...NONE.

&&

$$

SYNOPSIS AND MODEL DISCUSSION...CC
SOUTHCENTRAL ALASKA...SEB
SOUTHWEST ALASKA/BERING SEA/ALEUTIANS...KH
LONG TERM...DS




000
FXAK68 PAFC 240723 AAA
AFDAFC

SOUTHCENTRAL AND SOUTHWEST ALASKA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE ANCHORAGE AK
1021 PM AKST SUN NOV 23 2014

UPDATED SOUTHCENTRAL SHORT TERM DISCUSSION

ANALYSIS AND UPPER LEVELS...
A 980S MB LOW SE OF SAND POINT IS STACKED UNDER THE UPPER CENTER
AND IS SLOWLY DRIFTING EAST AND WEAKENING. WAVES EMBEDDED IN THE
BROAD UPPER LEVEL CYCLONIC FLOW PRODUCED RAIN SHOWERS ACROSS THE
GULF AND AK PEN WITH MIXED SHOWERS TO SNOW SHOWERS OVER BRISTOL
BAY AND THE REMAINDER OF SOUTHCENTRAL. AN ELEVATED WARM LAYER AND BELOW
FREEZING SURFACE TEMPS PRODUCED ISOLATED POCKETS OF LIGHT FREEZING
RAIN OVER THE EASTERN BRISTOL BAY ZONE THIS MORNING. THE KING
SALMON NEXRAD SHOWED ANOTHER BATCH OF MOISTURE MOVING NORTH THIS
AFTERNOON...SO THE THREAT OF FREEZING RAIN MAY CONTINUE UNTIL
SURFACE TEMPS RISE ABOVE FREEZING THIS AFTERNOON. GUSTY NORTHWEST
WINDS ON THE BACKSIDE OF LOW SOUTH OF THE AK PEN CONTINUE ALONG
THE WESTERN AK PEN AND EAST ALEUTIANS. GUSTY EAST WINDS CONTINUE
ACROSS THE NORTH GULF WITH NE WINDS OVER THE WESTERN GULF AND
NORTHERLY GAP FLOWS ACROSS THE MATANUSKA VALLEY.

MODEL DISCUSSION ...
THOUGH THERE ARE SOME MODEL DIFFERENCES THROUGH THE SHORT TERM
(TUE AFTERNOON) THE IMPACTS ARE FAIRLY SIMILAR. THE TIMING OF THE
FRONT ACROSS THE BERING SEA WITH ACCOMPANYING GALES AND RAIN ARE
SIMILAR AS WELL AS SHOWERS WITH WAVES MOVING NORTH ACROSS THE GULF
AND SOUTHCENTRAL. SIGNIFICANT DIFFERENCES DEVELOP OUT WEST WITH
THE TIMING OF THE NEXT WAVE WHICH APPROACHES THE EASTERN ALEUTIANS
TUE NIGHT. THE LAST 2 RUNS OF THE EC HAVE COME IN SIGNIFICANTLY
FURTHER SOUTH WITH THIS FEATURE...AND NOW KEEP IT ENTIRELY OUT OF
THE AOR. THE GFS/NAM/GEM ON THE OTHER HAND ARE IN GOOD AGREEMENT
WITH A GALE FORCE LOW APPROACHING THE EASTERN ALEUTIANS BY LATE
TUESDAY NIGHT. THIS FURTHER NORTH SOLUTION WAS PREFERRED FOR THE
AFTERNOON PACKAGE AS IT WAS CLOSER TO THE CURRENT FORECAST. LATER
RUNS WILL HOWEVER NEED TO BE MONITORED...AS AGREEMENT IN
SOUTHERLY SOLUTION WOULD RESULT IN A SIGNIFICANT CHANGE TO THE
FORECAST.

SHORT TERM FORECAST SOUTHCENTRAL ALASKA (DAYS 1 AND 2)...
A WEAK FRONT ALONG THE NORTH GULF COAST WILL KEEP SHOWER ACTIVITY
MOST ACTIVE ACROSS COASTAL LOCATIONS TONIGHT...WITH MUCH MORE
SPORADIC AND LIGHT SHOWER ACTIVITY INLAND. RAIN AND SNOW SHOWERS
WILL BE MOST ACTIVE FROM EASTERN PRINCE WILLIAM SOUND
EASTWARD...WITH ACCUMULATING SNOW ACROSS PORTIONS OF THOMPSON PASS
INTO THE SOUTHERN COPPER RIVER BASIN. EVENTUALLY THE LOW WILL
TRACK EAST TOMORROW...WITH SHOWERS GRADUALLY DIMINISHING THROUGH
TUESDAY NIGHT. MINOR ACCUMULATIONS WILL BE POSSIBLE ACROSS FAVORED
UPSLOPE REGIONS IN THE TALKEETNA MOUNTAINS AND NORTH OF TALKEETNA
THROUGH BROAD PASS INTO MONDAY NIGHT. HIGH PRESSURE BUILDS IN
WEDNESDAY AND THURSDAY...BRINGING DRY WEATHER TO ALL OF
SOUTHCENTRAL.

SHORT TERM FORECAST SOUTHWEST ALASKA (TONIGHT THROUGH WEDNESDAY)...
A WEAK SHORTWAVE ALOFT WILL BRING RAIN FROM THE ALASKA
PENINSULA...BECOMING SNOW MIXED WITH RAIN AS IT STRETCHES INTO
WESTERN BRISTOL BAY. THIS WILL BRING ACCUMULATING SNOW TO WESTERN
BRISTOL BAY THIS EVENING...ESPECIALLY IN THE DILLINGHAM
AREA...WHERE COLD AIR ALOFT STILL EXISTS. THERE IS A SLIGHT CHANCE
THAT ENOUGH WARM AIR ALOFT WILL REACH WESTERN BRISTOL BAY LATE
TONIGHT TO CREATE AREAS OF FREEZING RAIN...HOWEVER THIS SHOULD NOT
BE VERY WIDESPREAD. AREAS FURTHER EAST WILL REMAIN AS RAIN WITH
EASTERLY FLOW ALOFT.

THE ENTIRE AREA WILL THEN BEGIN TO CLEAR OUT ON MONDAY
MORNING AS THE STATIONARY UPPER TROUGH DISSIPATES AND WEAK
RIDGING CURRENTLY OVER THE BERING MOVES IN. THIS WILL KEEP SKIES
GENERALLY WITH PRECIPITATION LIMITED TO A FEW PASSING SHOWERS. A
WEAK FRONT WILL THEN APPROACH THE KUSKOKWIM DELTA ON
TUESDAY...BRINGING A CHANCE OF RAIN TO THE AREAS. RIDGING WILL
HOWEVER REMAIN OVER THE KUSKOKWIM VALLEY AND BRISTOL BAY...KEEPING
THE AREA DRY WITH LIGHT WINDS INTO MID WEEK.

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

AFTER A WEAKENING AREA OF RAIN AND SNOW SHOWERS FROM THE PRIBILOF
ISLANDS INTO THE AKPENN DISSIPATES LATE TONIGHT...THE WEATHER WILL
QUICKLY BECOME DOMINATED BY A FRONTAL SYSTEM CURRENTLY ENTERING
THE WESTERN ALEUTIANS. THIS SYSTEM WILL BECOME A LOW COMPLEX WITH
MULTIPLE CENTERS OVER THE WESTERN BERING BY MONDAY AFTERNOON. WITH
CONSIDERABLE MODEL DISAGREEMENT WITH BOTH THE LOCATION AND
INTENSITY OF THESE LOWS...FORECAST CONFIDENCE QUICKLY DIMINISHES
WITH A DEVELOPING LOW APPROACHING THE EASTERN ALEUTIANS TUESDAY.
IT DOES APPEAR THAT THIS SETUP WILL KEEP WET WEATHER OVER THE
BERING WITH A POTENTIAL FOR GALE FORCE WINDS IN THE EASTERN
ALEUTIANS BY WEDNESDAY.

LONG TERM FORECAST (DAYS 4 THROUGH 7)...
THE OUTCOME OF THE LONG TERM FORECAST REMAINS HIGHLY DEPENDENT
THE TRACK AND STRENGTH OF THE COMPLEX LOW AS IT BEGINS TO
CONSOLIDATE OVER THE BERING SEA WEDNESDAY. GLOBAL MODELS CONTINUE
TO STRUGGLE WITH THE DETAILS OF THIS SYSTEM...KEEPING FORECAST
CONFIDENCE LOW IN THE TIMING AND STRENGTH OF THE ASSOCIATED
FRONTAL SYSTEM AS IT PROGRESSES EASTWARD. THE MORE NORTHERLY GFS
SOLUTION IS SLOWER TO CONSOLIDATE THE LOW OVER THE NORTHERN
BERING...BUT QUICKEST WITH BRINGING FRONTAL WINDS AND
PRECIPITATION TO THE CENTRAL ALEUTIANS WEDNESDAY MORNING AND
EVENTUALLY INTO THE SOUTHWEST COAST THURSDAY MORNING. THE MORE
SOUTHERLY ECMWF SOLUTION CONSOLIDATES THE LOW QUICKER OVER THE
SOUTHERN BERING...BUT IS SLOWER TO BRING THE FRONTAL WINDS AND
PRECIPITATION INTO THE CENTRAL ALEUTIANS WEDNESDAY AFTERNOON AND
EVENTUALLY INTO THE SOUTHWEST COAST THURSDAY AFTERNOON.

GLOBAL GUIDANCE HAS BEEN SIGNALING THAT THIS ACTIVITY OUT WEST
WILL AMPLIFY A RIDGE OF HIGH PRESSURE IN THE GULF WHICH WILL ACT
TO SLOW THE PROGRESSION OF THIS PATTERN...AND WILL KEEP
SOUTHCENTRAL ALASKA DRY THROUGH THE END OF THE WEEK. EXPECT
SLIGHTLY ABOVE NORMAL TEMPERATURES AND LIGHT WINDS FOR THE WEEK.
CONFIDENCE BEGINS TO DIMINISH INTO THE WEEKEND...WHERE THE
LONGEVITY OF THIS PATTERN BECOMES HIGHLY DEPENDENT ON WHICH MODEL
SOLUTION VERIFIES. A MORE SOUTHERLY SOLUTION (ECMWF) REGARDING
THE LOW OUT WEST WOULD FAVOR DRIER CONDITIONS PERSISTING THROUGH
MUCH OF THE WEEKEND....WHEREAS THE MORE NORTHERLY SOLUTION (GFS)
DEAMPLIFIES THE RIDGE QUICKER AND BRINGS A WEAK SHORTWAVE THROUGH
SOUTHCENTRAL ON SUNDAY.

AFC WATCHES/WARNINGS/ADVISORIES...
PUBLIC...NONE.
MARINE...NONE.
FIRE WEATHER...NONE.


&&

$$




000
FXAK68 PAFC 240723 AAA
AFDAFC

SOUTHCENTRAL AND SOUTHWEST ALASKA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE ANCHORAGE AK
1021 PM AKST SUN NOV 23 2014

UPDATED SOUTHCENTRAL SHORT TERM DISCUSSION

ANALYSIS AND UPPER LEVELS...
A 980S MB LOW SE OF SAND POINT IS STACKED UNDER THE UPPER CENTER
AND IS SLOWLY DRIFTING EAST AND WEAKENING. WAVES EMBEDDED IN THE
BROAD UPPER LEVEL CYCLONIC FLOW PRODUCED RAIN SHOWERS ACROSS THE
GULF AND AK PEN WITH MIXED SHOWERS TO SNOW SHOWERS OVER BRISTOL
BAY AND THE REMAINDER OF SOUTHCENTRAL. AN ELEVATED WARM LAYER AND BELOW
FREEZING SURFACE TEMPS PRODUCED ISOLATED POCKETS OF LIGHT FREEZING
RAIN OVER THE EASTERN BRISTOL BAY ZONE THIS MORNING. THE KING
SALMON NEXRAD SHOWED ANOTHER BATCH OF MOISTURE MOVING NORTH THIS
AFTERNOON...SO THE THREAT OF FREEZING RAIN MAY CONTINUE UNTIL
SURFACE TEMPS RISE ABOVE FREEZING THIS AFTERNOON. GUSTY NORTHWEST
WINDS ON THE BACKSIDE OF LOW SOUTH OF THE AK PEN CONTINUE ALONG
THE WESTERN AK PEN AND EAST ALEUTIANS. GUSTY EAST WINDS CONTINUE
ACROSS THE NORTH GULF WITH NE WINDS OVER THE WESTERN GULF AND
NORTHERLY GAP FLOWS ACROSS THE MATANUSKA VALLEY.

MODEL DISCUSSION ...
THOUGH THERE ARE SOME MODEL DIFFERENCES THROUGH THE SHORT TERM
(TUE AFTERNOON) THE IMPACTS ARE FAIRLY SIMILAR. THE TIMING OF THE
FRONT ACROSS THE BERING SEA WITH ACCOMPANYING GALES AND RAIN ARE
SIMILAR AS WELL AS SHOWERS WITH WAVES MOVING NORTH ACROSS THE GULF
AND SOUTHCENTRAL. SIGNIFICANT DIFFERENCES DEVELOP OUT WEST WITH
THE TIMING OF THE NEXT WAVE WHICH APPROACHES THE EASTERN ALEUTIANS
TUE NIGHT. THE LAST 2 RUNS OF THE EC HAVE COME IN SIGNIFICANTLY
FURTHER SOUTH WITH THIS FEATURE...AND NOW KEEP IT ENTIRELY OUT OF
THE AOR. THE GFS/NAM/GEM ON THE OTHER HAND ARE IN GOOD AGREEMENT
WITH A GALE FORCE LOW APPROACHING THE EASTERN ALEUTIANS BY LATE
TUESDAY NIGHT. THIS FURTHER NORTH SOLUTION WAS PREFERRED FOR THE
AFTERNOON PACKAGE AS IT WAS CLOSER TO THE CURRENT FORECAST. LATER
RUNS WILL HOWEVER NEED TO BE MONITORED...AS AGREEMENT IN
SOUTHERLY SOLUTION WOULD RESULT IN A SIGNIFICANT CHANGE TO THE
FORECAST.

SHORT TERM FORECAST SOUTHCENTRAL ALASKA (DAYS 1 AND 2)...
A WEAK FRONT ALONG THE NORTH GULF COAST WILL KEEP SHOWER ACTIVITY
MOST ACTIVE ACROSS COASTAL LOCATIONS TONIGHT...WITH MUCH MORE
SPORADIC AND LIGHT SHOWER ACTIVITY INLAND. RAIN AND SNOW SHOWERS
WILL BE MOST ACTIVE FROM EASTERN PRINCE WILLIAM SOUND
EASTWARD...WITH ACCUMULATING SNOW ACROSS PORTIONS OF THOMPSON PASS
INTO THE SOUTHERN COPPER RIVER BASIN. EVENTUALLY THE LOW WILL
TRACK EAST TOMORROW...WITH SHOWERS GRADUALLY DIMINISHING THROUGH
TUESDAY NIGHT. MINOR ACCUMULATIONS WILL BE POSSIBLE ACROSS FAVORED
UPSLOPE REGIONS IN THE TALKEETNA MOUNTAINS AND NORTH OF TALKEETNA
THROUGH BROAD PASS INTO MONDAY NIGHT. HIGH PRESSURE BUILDS IN
WEDNESDAY AND THURSDAY...BRINGING DRY WEATHER TO ALL OF
SOUTHCENTRAL.

SHORT TERM FORECAST SOUTHWEST ALASKA (TONIGHT THROUGH WEDNESDAY)...
A WEAK SHORTWAVE ALOFT WILL BRING RAIN FROM THE ALASKA
PENINSULA...BECOMING SNOW MIXED WITH RAIN AS IT STRETCHES INTO
WESTERN BRISTOL BAY. THIS WILL BRING ACCUMULATING SNOW TO WESTERN
BRISTOL BAY THIS EVENING...ESPECIALLY IN THE DILLINGHAM
AREA...WHERE COLD AIR ALOFT STILL EXISTS. THERE IS A SLIGHT CHANCE
THAT ENOUGH WARM AIR ALOFT WILL REACH WESTERN BRISTOL BAY LATE
TONIGHT TO CREATE AREAS OF FREEZING RAIN...HOWEVER THIS SHOULD NOT
BE VERY WIDESPREAD. AREAS FURTHER EAST WILL REMAIN AS RAIN WITH
EASTERLY FLOW ALOFT.

THE ENTIRE AREA WILL THEN BEGIN TO CLEAR OUT ON MONDAY
MORNING AS THE STATIONARY UPPER TROUGH DISSIPATES AND WEAK
RIDGING CURRENTLY OVER THE BERING MOVES IN. THIS WILL KEEP SKIES
GENERALLY WITH PRECIPITATION LIMITED TO A FEW PASSING SHOWERS. A
WEAK FRONT WILL THEN APPROACH THE KUSKOKWIM DELTA ON
TUESDAY...BRINGING A CHANCE OF RAIN TO THE AREAS. RIDGING WILL
HOWEVER REMAIN OVER THE KUSKOKWIM VALLEY AND BRISTOL BAY...KEEPING
THE AREA DRY WITH LIGHT WINDS INTO MID WEEK.

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

AFTER A WEAKENING AREA OF RAIN AND SNOW SHOWERS FROM THE PRIBILOF
ISLANDS INTO THE AKPENN DISSIPATES LATE TONIGHT...THE WEATHER WILL
QUICKLY BECOME DOMINATED BY A FRONTAL SYSTEM CURRENTLY ENTERING
THE WESTERN ALEUTIANS. THIS SYSTEM WILL BECOME A LOW COMPLEX WITH
MULTIPLE CENTERS OVER THE WESTERN BERING BY MONDAY AFTERNOON. WITH
CONSIDERABLE MODEL DISAGREEMENT WITH BOTH THE LOCATION AND
INTENSITY OF THESE LOWS...FORECAST CONFIDENCE QUICKLY DIMINISHES
WITH A DEVELOPING LOW APPROACHING THE EASTERN ALEUTIANS TUESDAY.
IT DOES APPEAR THAT THIS SETUP WILL KEEP WET WEATHER OVER THE
BERING WITH A POTENTIAL FOR GALE FORCE WINDS IN THE EASTERN
ALEUTIANS BY WEDNESDAY.

LONG TERM FORECAST (DAYS 4 THROUGH 7)...
THE OUTCOME OF THE LONG TERM FORECAST REMAINS HIGHLY DEPENDENT
THE TRACK AND STRENGTH OF THE COMPLEX LOW AS IT BEGINS TO
CONSOLIDATE OVER THE BERING SEA WEDNESDAY. GLOBAL MODELS CONTINUE
TO STRUGGLE WITH THE DETAILS OF THIS SYSTEM...KEEPING FORECAST
CONFIDENCE LOW IN THE TIMING AND STRENGTH OF THE ASSOCIATED
FRONTAL SYSTEM AS IT PROGRESSES EASTWARD. THE MORE NORTHERLY GFS
SOLUTION IS SLOWER TO CONSOLIDATE THE LOW OVER THE NORTHERN
BERING...BUT QUICKEST WITH BRINGING FRONTAL WINDS AND
PRECIPITATION TO THE CENTRAL ALEUTIANS WEDNESDAY MORNING AND
EVENTUALLY INTO THE SOUTHWEST COAST THURSDAY MORNING. THE MORE
SOUTHERLY ECMWF SOLUTION CONSOLIDATES THE LOW QUICKER OVER THE
SOUTHERN BERING...BUT IS SLOWER TO BRING THE FRONTAL WINDS AND
PRECIPITATION INTO THE CENTRAL ALEUTIANS WEDNESDAY AFTERNOON AND
EVENTUALLY INTO THE SOUTHWEST COAST THURSDAY AFTERNOON.

GLOBAL GUIDANCE HAS BEEN SIGNALING THAT THIS ACTIVITY OUT WEST
WILL AMPLIFY A RIDGE OF HIGH PRESSURE IN THE GULF WHICH WILL ACT
TO SLOW THE PROGRESSION OF THIS PATTERN...AND WILL KEEP
SOUTHCENTRAL ALASKA DRY THROUGH THE END OF THE WEEK. EXPECT
SLIGHTLY ABOVE NORMAL TEMPERATURES AND LIGHT WINDS FOR THE WEEK.
CONFIDENCE BEGINS TO DIMINISH INTO THE WEEKEND...WHERE THE
LONGEVITY OF THIS PATTERN BECOMES HIGHLY DEPENDENT ON WHICH MODEL
SOLUTION VERIFIES. A MORE SOUTHERLY SOLUTION (ECMWF) REGARDING
THE LOW OUT WEST WOULD FAVOR DRIER CONDITIONS PERSISTING THROUGH
MUCH OF THE WEEKEND....WHEREAS THE MORE NORTHERLY SOLUTION (GFS)
DEAMPLIFIES THE RIDGE QUICKER AND BRINGS A WEAK SHORTWAVE THROUGH
SOUTHCENTRAL ON SUNDAY.

AFC WATCHES/WARNINGS/ADVISORIES...
PUBLIC...NONE.
MARINE...NONE.
FIRE WEATHER...NONE.


&&

$$





000
FXAK68 PAFC 240721 AAA
AFDAFC

SOUTHCENTRAL AND SOUTHWEST ALASKA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE ANCHORAGE AK
1021 PM AKST SUN NOV 23 2014

UPDATED SOUTHCENTRAL SHORT TERM DISCUSSION

ANALYSIS AND UPPER LEVELS...
A 980S MB LOW SE OF SAND POINT IS STACKED UNDER THE UPPER CENTER
AND IS SLOWLY DRIFTING EAST AND WEAKENING. WAVES EMBEDDED IN THE
BROAD UPPER LEVEL CYCLONIC FLOW PRODUCED RAIN SHOWERS ACROSS THE
GULF AND AK PEN WITH MIXED SHOWERS TO SNOW SHOWERS OVER BRISTOL
BAY AND THE REMAINDER OF SOUTHCENTRAL. AN ELEVATED WARM LAYER AND BELOW
FREEZING SURFACE TEMPS PRODUCED ISOLATED POCKETS OF LIGHT FREEZING
RAIN OVER THE EASTERN BRISTOL BAY ZONE THIS MORNING. THE KING
SALMON NEXRAD SHOWED ANOTHER BATCH OF MOISTURE MOVING NORTH THIS
AFTERNOON...SO THE THREAT OF FREEZING RAIN MAY CONTINUE UNTIL
SURFACE TEMPS RISE ABOVE FREEZING THIS AFTERNOON. GUSTY NORTHWEST
WINDS ON THE BACKSIDE OF LOW SOUTH OF THE AK PEN CONTINUE ALONG
THE WESTERN AK PEN AND EAST ALEUTIANS. GUSTY EAST WINDS CONTINUE
ACROSS THE NORTH GULF WITH NE WINDS OVER THE WESTERN GULF AND
NORTHERLY GAP FLOWS ACROSS THE MATANUSKA VALLEY.

MODEL DISCUSSION ...
THOUGH THERE ARE SOME MODEL DIFFERENCES THROUGH THE SHORT TERM
(TUE AFTERNOON) THE IMPACTS ARE FAIRLY SIMILAR. THE TIMING OF THE
FRONT ACROSS THE BERING SEA WITH ACCOMPANYING GALES AND RAIN ARE
SIMILAR AS WELL AS SHOWERS WITH WAVES MOVING NORTH ACROSS THE GULF
AND SOUTHCENTRAL. SIGNIFICANT DIFFERENCES DEVELOP OUT WEST WITH
THE TIMING OF THE NEXT WAVE WHICH APPROACHES THE EASTERN ALEUTIANS
TUE NIGHT. THE LAST 2 RUNS OF THE EC HAVE COME IN SIGNIFICANTLY
FURTHER SOUTH WITH THIS FEATURE...AND NOW KEEP IT ENTIRELY OUT OF
THE AOR. THE GFS/NAM/GEM ON THE OTHER HAND ARE IN GOOD AGREEMENT
WITH A GALE FORCE LOW APPROACHING THE EASTERN ALEUTIANS BY LATE
TUESDAY NIGHT. THIS FURTHER NORTH SOLUTION WAS PREFERRED FOR THE
AFTERNOON PACKAGE AS IT WAS CLOSER TO THE CURRENT FORECAST. LATER
RUNS WILL HOWEVER NEED TO BE MONITORED...AS AGREEMENT IN
SOUTHERLY SOLUTION WOULD RESULT IN A SIGNIFICANT CHANGE TO THE
FORECAST.

SHORT TERM FORECAST SOUTHCENTRAL ALASKA (DAYS 1 AND 2)...
A WEAK FRONT ALONG THE NORTH GULF COAST WILL KEEP SHOWER ACTIVITY
MOST ACTIVE ACROSS COASTAL LOCATIONS TONIGHT...WITH MUCH MORE
SPORADIC AND LIGHT SHOWER ACTIVITY INLAND. RAIN AND SNOW SHOWERS
WILL BE MOST ACTIVE FROM EASTERN PRINCE WILLIAM SOUND
EASTWARD...WITH ACCUMULATING SNOW ACROSS PORTIONS OF THOMPSON PASS
INTO THE SOUTHERN COPPER RIVER BASIN. EVENTUALLY THE LOW WILL
TRACK EAST TOMORROW...WITH SHOWERS GRADUALLY DIMINISHING THROUGH
TUESDAY NIGHT. MINOR ACCUMULATIONS WILL BE POSSIBLE ACROSS FAVORED
UPSLOPE REGIONS IN THE TALKEETNA MOUNTAINS AND NORTH OF TALKEETNA
THROUGH BROAD PASS INTO MONDAY NIGHT. HIGH PRESSURE BUILDS IN
WEDNESDAY AND THURSDAY...BRINGING DRY WEATHER TO ALL OF
SOUTHCENTRAL.

SHORT TERM FORECAST SOUTHWEST ALASKA (TONIGHT THROUGH WEDNESDAY)...
A WEAK SHORTWAVE ALOFT WILL BRING RAIN FROM THE ALASKA
PENINSULA...BECOMING SNOW MIXED WITH RAIN AS IT STRETCHES INTO
WESTERN BRISTOL BAY. THIS WILL BRING ACCUMULATING SNOW TO WESTERN
BRISTOL BAY THIS EVENING...ESPECIALLY IN THE DILLINGHAM
AREA...WHERE COLD AIR ALOFT STILL EXISTS. THERE IS A SLIGHT CHANCE
THAT ENOUGH WARM AIR ALOFT WILL REACH WESTERN BRISTOL BAY LATE
TONIGHT TO CREATE AREAS OF FREEZING RAIN...HOWEVER THIS SHOULD NOT
BE VERY WIDESPREAD. AREAS FURTHER EAST WILL REMAIN AS RAIN WITH
EASTERLY FLOW ALOFT.

THE ENTIRE AREA WILL THEN BEGIN TO CLEAR OUT ON MONDAY
MORNING AS THE STATIONARY UPPER TROUGH DISSIPATES AND WEAK
RIDGING CURRENTLY OVER THE BERING MOVES IN. THIS WILL KEEP SKIES
GENERALLY WITH PRECIPITATION LIMITED TO A FEW PASSING SHOWERS. A
WEAK FRONT WILL THEN APPROACH THE KUSKOKWIM DELTA ON
TUESDAY...BRINGING A CHANCE OF RAIN TO THE AREAS. RIDGING WILL
HOWEVER REMAIN OVER THE KUSKOKWIM VALLEY AND BRISTOL BAY...KEEPING
THE AREA DRY WITH LIGHT WINDS INTO MID WEEK.

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

AFTER A WEAKENING AREA OF RAIN AND SNOW SHOWERS FROM THE PRIBILOF
ISLANDS INTO THE AKPENN DISSIPATES LATE TONIGHT...THE WEATHER WILL
QUICKLY BECOME DOMINATED BY A FRONTAL SYSTEM CURRENTLY ENTERING
THE WESTERN ALEUTIANS. THIS SYSTEM WILL BECOME A LOW COMPLEX WITH
MULTIPLE CENTERS OVER THE WESTERN BERING BY MONDAY AFTERNOON. WITH
CONSIDERABLE MODEL DISAGREEMENT WITH BOTH THE LOCATION AND
INTENSITY OF THESE LOWS...FORECAST CONFIDENCE QUICKLY DIMINISHES
WITH A DEVELOPING LOW APPROACHING THE EASTERN ALEUTIANS TUESDAY.
IT DOES APPEAR THAT THIS SETUP WILL KEEP WET WEATHER OVER THE
BERING WITH A POTENTIAL FOR GALE FORCE WINDS IN THE EASTERN
ALEUTIANS BY WEDNESDAY.

LONG TERM FORECAST (DAYS 4 THROUGH 7)...
THE OUTCOME OF THE LONG TERM FORECAST REMAINS HIGHLY DEPENDENT
THE TRACK AND STRENGTH OF THE COMPLEX LOW AS IT BEGINS TO
CONSOLIDATE OVER THE BERING SEA WEDNESDAY. GLOBAL MODELS CONTINUE
TO STRUGGLE WITH THE DETAILS OF THIS SYSTEM...KEEPING FORECAST
CONFIDENCE LOW IN THE TIMING AND STRENGTH OF THE ASSOCIATED
FRONTAL SYSTEM AS IT PROGRESSES EASTWARD. THE MORE NORTHERLY GFS
SOLUTION IS SLOWER TO CONSOLIDATE THE LOW OVER THE NORTHERN
BERING...BUT QUICKEST WITH BRINGING FRONTAL WINDS AND
PRECIPITATION TO THE CENTRAL ALEUTIANS WEDNESDAY MORNING AND
EVENTUALLY INTO THE SOUTHWEST COAST THURSDAY MORNING. THE MORE
SOUTHERLY ECMWF SOLUTION CONSOLIDATES THE LOW QUICKER OVER THE
SOUTHERN BERING...BUT IS SLOWER TO BRING THE FRONTAL WINDS AND
PRECIPITATION INTO THE CENTRAL ALEUTIANS WEDNESDAY AFTERNOON AND
EVENTUALLY INTO THE SOUTHWEST COAST THURSDAY AFTERNOON.

GLOBAL GUIDANCE HAS BEEN SIGNALING THAT THIS ACTIVITY OUT WEST
WILL AMPLIFY A RIDGE OF HIGH PRESSURE IN THE GULF WHICH WILL ACT
TO SLOW THE PROGRESSION OF THIS PATTERN...AND WILL KEEP
SOUTHCENTRAL ALASKA DRY THROUGH THE END OF THE WEEK. EXPECT
SLIGHTLY ABOVE NORMAL TEMPERATURES AND LIGHT WINDS FOR THE WEEK.
CONFIDENCE BEGINS TO DIMINISH INTO THE WEEKEND...WHERE THE
LONGEVITY OF THIS PATTERN BECOMES HIGHLY DEPENDENT ON WHICH MODEL
SOLUTION VERIFIES. A MORE SOUTHERLY SOLUTION (ECMWF) REGARDING
THE LOW OUT WEST WOULD FAVOR DRIER CONDITIONS PERSISTING THROUGH
MUCH OF THE WEEKEND....WHEREAS THE MORE NORTHERLY SOLUTION (GFS)
DEAMPLIFIES THE RIDGE QUICKER AND BRINGS A WEAK SHORTWAVE THROUGH
SOUTHCENTRAL ON SUNDAY.

AFC WATCHES/WARNINGS/ADVISORIES...
PUBLIC...NONE.
MARINE...NONE.
FIRE WEATHER...NONE.


&&

.AFC WATCHES/WARNINGS/ADVISORIES...
PUBLIC...NONE.
MARINE...NONE.
FIRE WEATHER...NONE.

&&

$$

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




000
FXAK68 PAFC 240721 AAA
AFDAFC

SOUTHCENTRAL AND SOUTHWEST ALASKA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE ANCHORAGE AK
1021 PM AKST SUN NOV 23 2014

UPDATED SOUTHCENTRAL SHORT TERM DISCUSSION

ANALYSIS AND UPPER LEVELS...
A 980S MB LOW SE OF SAND POINT IS STACKED UNDER THE UPPER CENTER
AND IS SLOWLY DRIFTING EAST AND WEAKENING. WAVES EMBEDDED IN THE
BROAD UPPER LEVEL CYCLONIC FLOW PRODUCED RAIN SHOWERS ACROSS THE
GULF AND AK PEN WITH MIXED SHOWERS TO SNOW SHOWERS OVER BRISTOL
BAY AND THE REMAINDER OF SOUTHCENTRAL. AN ELEVATED WARM LAYER AND BELOW
FREEZING SURFACE TEMPS PRODUCED ISOLATED POCKETS OF LIGHT FREEZING
RAIN OVER THE EASTERN BRISTOL BAY ZONE THIS MORNING. THE KING
SALMON NEXRAD SHOWED ANOTHER BATCH OF MOISTURE MOVING NORTH THIS
AFTERNOON...SO THE THREAT OF FREEZING RAIN MAY CONTINUE UNTIL
SURFACE TEMPS RISE ABOVE FREEZING THIS AFTERNOON. GUSTY NORTHWEST
WINDS ON THE BACKSIDE OF LOW SOUTH OF THE AK PEN CONTINUE ALONG
THE WESTERN AK PEN AND EAST ALEUTIANS. GUSTY EAST WINDS CONTINUE
ACROSS THE NORTH GULF WITH NE WINDS OVER THE WESTERN GULF AND
NORTHERLY GAP FLOWS ACROSS THE MATANUSKA VALLEY.

MODEL DISCUSSION ...
THOUGH THERE ARE SOME MODEL DIFFERENCES THROUGH THE SHORT TERM
(TUE AFTERNOON) THE IMPACTS ARE FAIRLY SIMILAR. THE TIMING OF THE
FRONT ACROSS THE BERING SEA WITH ACCOMPANYING GALES AND RAIN ARE
SIMILAR AS WELL AS SHOWERS WITH WAVES MOVING NORTH ACROSS THE GULF
AND SOUTHCENTRAL. SIGNIFICANT DIFFERENCES DEVELOP OUT WEST WITH
THE TIMING OF THE NEXT WAVE WHICH APPROACHES THE EASTERN ALEUTIANS
TUE NIGHT. THE LAST 2 RUNS OF THE EC HAVE COME IN SIGNIFICANTLY
FURTHER SOUTH WITH THIS FEATURE...AND NOW KEEP IT ENTIRELY OUT OF
THE AOR. THE GFS/NAM/GEM ON THE OTHER HAND ARE IN GOOD AGREEMENT
WITH A GALE FORCE LOW APPROACHING THE EASTERN ALEUTIANS BY LATE
TUESDAY NIGHT. THIS FURTHER NORTH SOLUTION WAS PREFERRED FOR THE
AFTERNOON PACKAGE AS IT WAS CLOSER TO THE CURRENT FORECAST. LATER
RUNS WILL HOWEVER NEED TO BE MONITORED...AS AGREEMENT IN
SOUTHERLY SOLUTION WOULD RESULT IN A SIGNIFICANT CHANGE TO THE
FORECAST.

SHORT TERM FORECAST SOUTHCENTRAL ALASKA (DAYS 1 AND 2)...
A WEAK FRONT ALONG THE NORTH GULF COAST WILL KEEP SHOWER ACTIVITY
MOST ACTIVE ACROSS COASTAL LOCATIONS TONIGHT...WITH MUCH MORE
SPORADIC AND LIGHT SHOWER ACTIVITY INLAND. RAIN AND SNOW SHOWERS
WILL BE MOST ACTIVE FROM EASTERN PRINCE WILLIAM SOUND
EASTWARD...WITH ACCUMULATING SNOW ACROSS PORTIONS OF THOMPSON PASS
INTO THE SOUTHERN COPPER RIVER BASIN. EVENTUALLY THE LOW WILL
TRACK EAST TOMORROW...WITH SHOWERS GRADUALLY DIMINISHING THROUGH
TUESDAY NIGHT. MINOR ACCUMULATIONS WILL BE POSSIBLE ACROSS FAVORED
UPSLOPE REGIONS IN THE TALKEETNA MOUNTAINS AND NORTH OF TALKEETNA
THROUGH BROAD PASS INTO MONDAY NIGHT. HIGH PRESSURE BUILDS IN
WEDNESDAY AND THURSDAY...BRINGING DRY WEATHER TO ALL OF
SOUTHCENTRAL.

SHORT TERM FORECAST SOUTHWEST ALASKA (TONIGHT THROUGH WEDNESDAY)...
A WEAK SHORTWAVE ALOFT WILL BRING RAIN FROM THE ALASKA
PENINSULA...BECOMING SNOW MIXED WITH RAIN AS IT STRETCHES INTO
WESTERN BRISTOL BAY. THIS WILL BRING ACCUMULATING SNOW TO WESTERN
BRISTOL BAY THIS EVENING...ESPECIALLY IN THE DILLINGHAM
AREA...WHERE COLD AIR ALOFT STILL EXISTS. THERE IS A SLIGHT CHANCE
THAT ENOUGH WARM AIR ALOFT WILL REACH WESTERN BRISTOL BAY LATE
TONIGHT TO CREATE AREAS OF FREEZING RAIN...HOWEVER THIS SHOULD NOT
BE VERY WIDESPREAD. AREAS FURTHER EAST WILL REMAIN AS RAIN WITH
EASTERLY FLOW ALOFT.

THE ENTIRE AREA WILL THEN BEGIN TO CLEAR OUT ON MONDAY
MORNING AS THE STATIONARY UPPER TROUGH DISSIPATES AND WEAK
RIDGING CURRENTLY OVER THE BERING MOVES IN. THIS WILL KEEP SKIES
GENERALLY WITH PRECIPITATION LIMITED TO A FEW PASSING SHOWERS. A
WEAK FRONT WILL THEN APPROACH THE KUSKOKWIM DELTA ON
TUESDAY...BRINGING A CHANCE OF RAIN TO THE AREAS. RIDGING WILL
HOWEVER REMAIN OVER THE KUSKOKWIM VALLEY AND BRISTOL BAY...KEEPING
THE AREA DRY WITH LIGHT WINDS INTO MID WEEK.

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

AFTER A WEAKENING AREA OF RAIN AND SNOW SHOWERS FROM THE PRIBILOF
ISLANDS INTO THE AKPENN DISSIPATES LATE TONIGHT...THE WEATHER WILL
QUICKLY BECOME DOMINATED BY A FRONTAL SYSTEM CURRENTLY ENTERING
THE WESTERN ALEUTIANS. THIS SYSTEM WILL BECOME A LOW COMPLEX WITH
MULTIPLE CENTERS OVER THE WESTERN BERING BY MONDAY AFTERNOON. WITH
CONSIDERABLE MODEL DISAGREEMENT WITH BOTH THE LOCATION AND
INTENSITY OF THESE LOWS...FORECAST CONFIDENCE QUICKLY DIMINISHES
WITH A DEVELOPING LOW APPROACHING THE EASTERN ALEUTIANS TUESDAY.
IT DOES APPEAR THAT THIS SETUP WILL KEEP WET WEATHER OVER THE
BERING WITH A POTENTIAL FOR GALE FORCE WINDS IN THE EASTERN
ALEUTIANS BY WEDNESDAY.

LONG TERM FORECAST (DAYS 4 THROUGH 7)...
THE OUTCOME OF THE LONG TERM FORECAST REMAINS HIGHLY DEPENDENT
THE TRACK AND STRENGTH OF THE COMPLEX LOW AS IT BEGINS TO
CONSOLIDATE OVER THE BERING SEA WEDNESDAY. GLOBAL MODELS CONTINUE
TO STRUGGLE WITH THE DETAILS OF THIS SYSTEM...KEEPING FORECAST
CONFIDENCE LOW IN THE TIMING AND STRENGTH OF THE ASSOCIATED
FRONTAL SYSTEM AS IT PROGRESSES EASTWARD. THE MORE NORTHERLY GFS
SOLUTION IS SLOWER TO CONSOLIDATE THE LOW OVER THE NORTHERN
BERING...BUT QUICKEST WITH BRINGING FRONTAL WINDS AND
PRECIPITATION TO THE CENTRAL ALEUTIANS WEDNESDAY MORNING AND
EVENTUALLY INTO THE SOUTHWEST COAST THURSDAY MORNING. THE MORE
SOUTHERLY ECMWF SOLUTION CONSOLIDATES THE LOW QUICKER OVER THE
SOUTHERN BERING...BUT IS SLOWER TO BRING THE FRONTAL WINDS AND
PRECIPITATION INTO THE CENTRAL ALEUTIANS WEDNESDAY AFTERNOON AND
EVENTUALLY INTO THE SOUTHWEST COAST THURSDAY AFTERNOON.

GLOBAL GUIDANCE HAS BEEN SIGNALING THAT THIS ACTIVITY OUT WEST
WILL AMPLIFY A RIDGE OF HIGH PRESSURE IN THE GULF WHICH WILL ACT
TO SLOW THE PROGRESSION OF THIS PATTERN...AND WILL KEEP
SOUTHCENTRAL ALASKA DRY THROUGH THE END OF THE WEEK. EXPECT
SLIGHTLY ABOVE NORMAL TEMPERATURES AND LIGHT WINDS FOR THE WEEK.
CONFIDENCE BEGINS TO DIMINISH INTO THE WEEKEND...WHERE THE
LONGEVITY OF THIS PATTERN BECOMES HIGHLY DEPENDENT ON WHICH MODEL
SOLUTION VERIFIES. A MORE SOUTHERLY SOLUTION (ECMWF) REGARDING
THE LOW OUT WEST WOULD FAVOR DRIER CONDITIONS PERSISTING THROUGH
MUCH OF THE WEEKEND....WHEREAS THE MORE NORTHERLY SOLUTION (GFS)
DEAMPLIFIES THE RIDGE QUICKER AND BRINGS A WEAK SHORTWAVE THROUGH
SOUTHCENTRAL ON SUNDAY.

AFC WATCHES/WARNINGS/ADVISORIES...
PUBLIC...NONE.
MARINE...NONE.
FIRE WEATHER...NONE.


&&

.AFC WATCHES/WARNINGS/ADVISORIES...
PUBLIC...NONE.
MARINE...NONE.
FIRE WEATHER...NONE.

&&

$$

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





000
FXAK68 PAFC 240131
AFDAFC

SOUTHCENTRAL AND SOUTHWEST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE ANCHORAGE AK
431 PM AKST SUN NOV 23 2014

.ANALYSIS AND UPPER LEVELS...
A 980S MB LOW SE OF SAND POINT IS STACKED UNDER THE UPPER CENTER
AND IS SLOWLY DRIFTING EAST AND WEAKENING. WAVES EMBEDDED IN THE
BROAD UPPER LEVEL CYCLONIC FLOW PRODUCED RAIN SHOWERS ACROSS THE
GULF AND AK PEN WITH MIXED SHOWERS TO SNOW SHOWERS OVER BRISTOL
BAY AND THE REMAINDER OF SOUTHCENTRAL. AN ELEVATED WARM LAYER AND BELOW
FREEZING SURFACE TEMPS PRODUCED ISOLATED POCKETS OF LIGHT FREEZING
RAIN OVER THE EASTERN BRISTOL BAY ZONE THIS MORNING. THE KING
SALMON NEXRAD SHOWED ANOTHER BATCH OF MOISTURE MOVING NORTH THIS
AFTERNOON...SO THE THREAT OF FREEZING RAIN MAY CONTINUE UNTIL
SURFACE TEMPS RISE ABOVE FREEZING THIS AFTERNOON. GUSTY NORTHWEST
WINDS ON THE BACKSIDE OF LOW SOUTH OF THE AK PEN CONTINUE ALONG
THE WESTERN AK PEN AND EAST ALEUTIANS. GUSTY EAST WINDS CONTINUE
ACROSS THE NORTH GULF WITH NE WINDS OVER THE WESTERN GULF AND
NORTHERLY GAP FLOWS ACROSS THE MATANUSKA VALLEY.

&&

.MODEL DISCUSSION ...
THOUGH THERE ARE SOME MODEL DIFFERENCES THROUGH THE SHORT TERM
(TUE AFTERNOON) THE IMPACTS ARE FAIRLY SIMILAR. THE TIMING OF THE
FRONT ACROSS THE BERING SEA WITH ACCOMPANYING GALES AND RAIN ARE
SIMILAR AS WELL AS SHOWERS WITH WAVES MOVING NORTH ACROSS THE GULF
AND SOUTHCENTRAL. SIGNIFICANT DIFFERENCES DEVELOP OUT WEST WITH
THE TIMING OF THE NEXT WAVE WHICH APPROACHES THE EASTERN ALEUTIANS
TUE NIGHT. THE LAST 2 RUNS OF THE EC HAVE COME IN SIGNIFICANTLY
FURTHER SOUTH WITH THIS FEATURE...AND NOW KEEP IT ENTIRELY OUT OF
THE AOR. THE GFS/NAM/GEM ON THE OTHER HAND ARE IN GOOD AGREEMENT
WITH A GALE FORCE LOW APPROACHING THE EASTERN ALEUTIANS BY LATE
TUESDAY NIGHT. THIS FURTHER NORTH SOLUTION WAS PREFERRED FOR THE
AFTERNOON PACKAGE AS IT WAS CLOSER TO THE CURRENT FORECAST. LATER
RUNS WILL HOWEVER NEED TO BE MONITORED...AS AGREEMENT IN
SOUTHERLY SOLUTION WOULD RESULT IN A SIGNIFICANT CHANGE TO THE
FORECAST.

&&

.SHORT TERM FORECAST SOUTHCENTRAL ALASKA (DAYS 1 AND 2)...
A SERIES OF UPPER LEVEL DISTURBANCES MOVING NORTHWARD ACROSS THE
GULF OF ALASKA TO SOUTHCENTRAL CONTINUE TO PROVIDE QUITE THE
CHALLENGE FOR THE PRECIPITATION FORECAST. FOR THE MOST PART SHOWERS
ASSOCIATED WITH THESE DISTURBANCES HAVE BEEN CONFINED TO THE GULF
COASTAL REGION WITH VERY FEW SHOWERS MAKING IT OVER THE COASTAL
MOUNTAINS. THIS IS DUE TO WEAK DOWNSLOPE FLOW AND LOW LEVEL DRY
AIR SUPPORTED BY OFFSHORE FLOW AT THE SURFACE. HOWEVER...THERE
HAVE BEEN A FEW STRONGER UPPER WAVES (ONE OF WHICH IS MOVING
THROUGH THIS MORNING) WHICH TEMPORARILY MODIFY THE LOW LEVEL FLOW
(TO WEAKEN DOWNSLOPING). PINPOINTING THE LOCATION AND AMOUNT OF
PRECIP IS VERY DIFFICULT...ESPECIALLY SINCE NONE OF THE MODELS
HAVE A GREAT HANDLE ON THE PLACEMENT AND TIMING OF INDIVIDUAL
FEATURES. SATELLITE AND RADAR TRENDS ARE THE MOST USEFUL TOOL IN
THIS SITUATION. BECAUSE OF THIS...FORECAST CONFIDENCE IN THE
PRECIP FORECAST BEYOND THE FIRST SIX HOURS IS LOW.

THE AIR MASS ACROSS THE REGION HAS CONTINUED A STEADY COOLING
TREND. THE IMMEDIATE COAST REMAINS ALL RAIN...BUT INTERIOR
PORTIONS OF WESTERN PRINCE WILLIAM SOUND HAVE SEEN SOME PERIODS OF
SNOW OR RAIN AND SNOW MIXED WITH VERY MINOR SNOW ACCUMULATIONS.
AS PER THE ANCHORAGE SOUNDING ANYTHING ON THE LEE SIDE OF THE
COASTAL RANGE WILL FALL AS SNOW.

UPPER LEVEL FLOW WILL SHIFT SUNDAY NIGHT INTO MONDAY AS THE LOW
ALONG THE ALASKA PENINSULA EXITS EASTWARD ACROSS THE GULF AND
UPPER FLOW OVER SOUTHCENTRAL BECOMES WESTERLY. PRECIP WILL THEN
BECOME FAVORED ALONG THE WEST SLOPES OF MOUNTAINS WHILE PRECIP IN
WESTERN PRINCE WILLIAM SOUND WILL DIMINISH.

&&

.SHORT TERM FORECAST SOUTHWEST ALASKA (TONIGHT THROUGH WEDNESDAY)...
A WEAK SHORTWAVE ALOFT WILL BRING RAIN FROM THE ALASKA
PENINSULA...BECOMING SNOW MIXED WITH RAIN AS IT STRETCHES INTO
WESTERN BRISTOL BAY. THIS WILL BRING ACCUMULATING SNOW TO WESTERN
BRISTOL BAY THIS EVENING...ESPECIALLY IN THE DILLINGHAM
AREA...WHERE COLD AIR ALOFT STILL EXISTS. THERE IS A SLIGHT CHANCE
THAT ENOUGH WARM AIR ALOFT WILL REACH WESTERN BRISTOL BAY LATE
TONIGHT TO CREATE AREAS OF FREEZING RAIN...HOWEVER THIS SHOULD NOT
BE VERY WIDESPREAD. AREAS FURTHER EAST WILL REMAIN AS RAIN WITH
EASTERLY FLOW ALOFT.

THE ENTIRE AREA WILL THEN BEGIN TO CLEAR OUT ON MONDAY
MORNING AS THE STATIONARY UPPER TROUGH DISSIPATES AND WEAK
RIDGING CURRENTLY OVER THE BERING MOVES IN. THIS WILL KEEP SKIES
GENERALLY WITH PRECIPITATION LIMITED TO A FEW PASSING SHOWERS. A
WEAK FRONT WILL THEN APPROACH THE KUSKOKWIM DELTA ON
TUESDAY...BRINGING A CHANCE OF RAIN TO THE AREAS. RIDGING WILL
HOWEVER REMAIN OVER THE KUSKOKWIM VALLEY AND BRISTOL BAY...KEEPING
THE AREA DRY WITH LIGHT WINDS INTO MID WEEK.

&&

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

AFTER A WEAKENING AREA OF RAIN AND SNOW SHOWERS FROM THE PRIBILOF
ISLANDS INTO THE AKPENN DISSIPATES LATE TONIGHT...THE WEATHER WILL
QUICKLY BECOME DOMINATED BY A FRONTAL SYSTEM CURRENTLY ENTERING
THE WESTERN ALEUTIANS. THIS SYSTEM WILL BECOME A LOW COMPLEX WITH
MULTIPLE CENTERS OVER THE WESTERN BERING BY MONDAY AFTERNOON. WITH
CONSIDERABLE MODEL DISAGREEMENT WITH BOTH THE LOCATION AND
INTENSITY OF THESE LOWS...FORECAST CONFIDENCE QUICKLY DIMINISHES
WITH A DEVELOPING LOW APPROACHING THE EASTERN ALEUTIANS TUESDAY.
IT DOES APPEAR THAT THIS SETUP WILL KEEP WET WEATHER OVER THE
BERING WITH A POTENTIAL FOR GALE FORCE WINDS IN THE EASTERN
ALEUTIANS BY WEDNESDAY.


&&

.LONG TERM FORECAST (DAYS 4 THROUGH 7)...
THE OUTCOME OF THE LONG TERM FORECAST REMAINS HIGHLY DEPENDENT
THE TRACK AND STRENGTH OF THE COMPLEX LOW AS IT BEGINS TO
CONSOLIDATE OVER THE BERING SEA WEDNESDAY. GLOBAL MODELS CONTINUE
TO STRUGGLE WITH THE DETAILS OF THIS SYSTEM...KEEPING FORECAST
CONFIDENCE LOW IN THE TIMING AND STRENGTH OF THE ASSOCIATED
FRONTAL SYSTEM AS IT PROGRESSES EASTWARD. THE MORE NORTHERLY GFS
SOLUTION IS SLOWER TO CONSOLIDATE THE LOW OVER THE NORTHERN
BERING...BUT QUICKEST WITH BRINGING FRONTAL WINDS AND
PRECIPITATION TO THE CENTRAL ALEUTIANS WEDNESDAY MORNING AND
EVENTUALLY INTO THE SOUTHWEST COAST THURSDAY MORNING. THE MORE
SOUTHERLY ECMWF SOLUTION CONSOLIDATES THE LOW QUICKER OVER THE
SOUTHERN BERING...BUT IS SLOWER TO BRING THE FRONTAL WINDS AND
PRECIPITATION INTO THE CENTRAL ALEUTIANS WEDNESDAY AFTERNOON AND
EVENTUALLY INTO THE SOUTHWEST COAST THURSDAY AFTERNOON.

GLOBAL GUIDANCE HAS BEEN SIGNALING THAT THIS ACTIVITY OUT WEST
WILL AMPLIFY A RIDGE OF HIGH PRESSURE IN THE GULF WHICH WILL ACT
TO SLOW THE PROGRESSION OF THIS PATTERN...AND WILL KEEP
SOUTHCENTRAL ALASKA DRY THROUGH THE END OF THE WEEK. EXPECT
SLIGHTLY ABOVE NORMAL TEMPERATURES AND LIGHT WINDS FOR THE WEEK.
CONFIDENCE BEGINS TO DIMINISH INTO THE WEEKEND...WHERE THE
LONGEVITY OF THIS PATTERN BECOMES HIGHLY DEPENDENT ON WHICH MODEL
SOLUTION VERIFIES. A MORE SOUTHERLY SOLUTION (ECMWF) REGARDING
THE LOW OUT WEST WOULD FAVOR DRIER CONDITIONS PERSISTING THROUGH
MUCH OF THE WEEKEND....WHEREAS THE MORE NORTHERLY SOLUTION (GFS)
DEAMPLIFIES THE RIDGE QUICKER AND BRINGS A WEAK SHORTWAVE THROUGH
SOUTHCENTRAL ON SUNDAY.

&&

.AFC WATCHES/WARNINGS/ADVISORIES...
PUBLIC...NONE.
MARINE...NONE.
FIRE WEATHER...NONE.

&&

$$





000
FXAK68 PAFC 240131
AFDAFC

SOUTHCENTRAL AND SOUTHWEST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE ANCHORAGE AK
431 PM AKST SUN NOV 23 2014

.ANALYSIS AND UPPER LEVELS...
A 980S MB LOW SE OF SAND POINT IS STACKED UNDER THE UPPER CENTER
AND IS SLOWLY DRIFTING EAST AND WEAKENING. WAVES EMBEDDED IN THE
BROAD UPPER LEVEL CYCLONIC FLOW PRODUCED RAIN SHOWERS ACROSS THE
GULF AND AK PEN WITH MIXED SHOWERS TO SNOW SHOWERS OVER BRISTOL
BAY AND THE REMAINDER OF SOUTHCENTRAL. AN ELEVATED WARM LAYER AND BELOW
FREEZING SURFACE TEMPS PRODUCED ISOLATED POCKETS OF LIGHT FREEZING
RAIN OVER THE EASTERN BRISTOL BAY ZONE THIS MORNING. THE KING
SALMON NEXRAD SHOWED ANOTHER BATCH OF MOISTURE MOVING NORTH THIS
AFTERNOON...SO THE THREAT OF FREEZING RAIN MAY CONTINUE UNTIL
SURFACE TEMPS RISE ABOVE FREEZING THIS AFTERNOON. GUSTY NORTHWEST
WINDS ON THE BACKSIDE OF LOW SOUTH OF THE AK PEN CONTINUE ALONG
THE WESTERN AK PEN AND EAST ALEUTIANS. GUSTY EAST WINDS CONTINUE
ACROSS THE NORTH GULF WITH NE WINDS OVER THE WESTERN GULF AND
NORTHERLY GAP FLOWS ACROSS THE MATANUSKA VALLEY.

&&

.MODEL DISCUSSION ...
THOUGH THERE ARE SOME MODEL DIFFERENCES THROUGH THE SHORT TERM
(TUE AFTERNOON) THE IMPACTS ARE FAIRLY SIMILAR. THE TIMING OF THE
FRONT ACROSS THE BERING SEA WITH ACCOMPANYING GALES AND RAIN ARE
SIMILAR AS WELL AS SHOWERS WITH WAVES MOVING NORTH ACROSS THE GULF
AND SOUTHCENTRAL. SIGNIFICANT DIFFERENCES DEVELOP OUT WEST WITH
THE TIMING OF THE NEXT WAVE WHICH APPROACHES THE EASTERN ALEUTIANS
TUE NIGHT. THE LAST 2 RUNS OF THE EC HAVE COME IN SIGNIFICANTLY
FURTHER SOUTH WITH THIS FEATURE...AND NOW KEEP IT ENTIRELY OUT OF
THE AOR. THE GFS/NAM/GEM ON THE OTHER HAND ARE IN GOOD AGREEMENT
WITH A GALE FORCE LOW APPROACHING THE EASTERN ALEUTIANS BY LATE
TUESDAY NIGHT. THIS FURTHER NORTH SOLUTION WAS PREFERRED FOR THE
AFTERNOON PACKAGE AS IT WAS CLOSER TO THE CURRENT FORECAST. LATER
RUNS WILL HOWEVER NEED TO BE MONITORED...AS AGREEMENT IN
SOUTHERLY SOLUTION WOULD RESULT IN A SIGNIFICANT CHANGE TO THE
FORECAST.

&&

.SHORT TERM FORECAST SOUTHCENTRAL ALASKA (DAYS 1 AND 2)...
A SERIES OF UPPER LEVEL DISTURBANCES MOVING NORTHWARD ACROSS THE
GULF OF ALASKA TO SOUTHCENTRAL CONTINUE TO PROVIDE QUITE THE
CHALLENGE FOR THE PRECIPITATION FORECAST. FOR THE MOST PART SHOWERS
ASSOCIATED WITH THESE DISTURBANCES HAVE BEEN CONFINED TO THE GULF
COASTAL REGION WITH VERY FEW SHOWERS MAKING IT OVER THE COASTAL
MOUNTAINS. THIS IS DUE TO WEAK DOWNSLOPE FLOW AND LOW LEVEL DRY
AIR SUPPORTED BY OFFSHORE FLOW AT THE SURFACE. HOWEVER...THERE
HAVE BEEN A FEW STRONGER UPPER WAVES (ONE OF WHICH IS MOVING
THROUGH THIS MORNING) WHICH TEMPORARILY MODIFY THE LOW LEVEL FLOW
(TO WEAKEN DOWNSLOPING). PINPOINTING THE LOCATION AND AMOUNT OF
PRECIP IS VERY DIFFICULT...ESPECIALLY SINCE NONE OF THE MODELS
HAVE A GREAT HANDLE ON THE PLACEMENT AND TIMING OF INDIVIDUAL
FEATURES. SATELLITE AND RADAR TRENDS ARE THE MOST USEFUL TOOL IN
THIS SITUATION. BECAUSE OF THIS...FORECAST CONFIDENCE IN THE
PRECIP FORECAST BEYOND THE FIRST SIX HOURS IS LOW.

THE AIR MASS ACROSS THE REGION HAS CONTINUED A STEADY COOLING
TREND. THE IMMEDIATE COAST REMAINS ALL RAIN...BUT INTERIOR
PORTIONS OF WESTERN PRINCE WILLIAM SOUND HAVE SEEN SOME PERIODS OF
SNOW OR RAIN AND SNOW MIXED WITH VERY MINOR SNOW ACCUMULATIONS.
AS PER THE ANCHORAGE SOUNDING ANYTHING ON THE LEE SIDE OF THE
COASTAL RANGE WILL FALL AS SNOW.

UPPER LEVEL FLOW WILL SHIFT SUNDAY NIGHT INTO MONDAY AS THE LOW
ALONG THE ALASKA PENINSULA EXITS EASTWARD ACROSS THE GULF AND
UPPER FLOW OVER SOUTHCENTRAL BECOMES WESTERLY. PRECIP WILL THEN
BECOME FAVORED ALONG THE WEST SLOPES OF MOUNTAINS WHILE PRECIP IN
WESTERN PRINCE WILLIAM SOUND WILL DIMINISH.

&&

.SHORT TERM FORECAST SOUTHWEST ALASKA (TONIGHT THROUGH WEDNESDAY)...
A WEAK SHORTWAVE ALOFT WILL BRING RAIN FROM THE ALASKA
PENINSULA...BECOMING SNOW MIXED WITH RAIN AS IT STRETCHES INTO
WESTERN BRISTOL BAY. THIS WILL BRING ACCUMULATING SNOW TO WESTERN
BRISTOL BAY THIS EVENING...ESPECIALLY IN THE DILLINGHAM
AREA...WHERE COLD AIR ALOFT STILL EXISTS. THERE IS A SLIGHT CHANCE
THAT ENOUGH WARM AIR ALOFT WILL REACH WESTERN BRISTOL BAY LATE
TONIGHT TO CREATE AREAS OF FREEZING RAIN...HOWEVER THIS SHOULD NOT
BE VERY WIDESPREAD. AREAS FURTHER EAST WILL REMAIN AS RAIN WITH
EASTERLY FLOW ALOFT.

THE ENTIRE AREA WILL THEN BEGIN TO CLEAR OUT ON MONDAY
MORNING AS THE STATIONARY UPPER TROUGH DISSIPATES AND WEAK
RIDGING CURRENTLY OVER THE BERING MOVES IN. THIS WILL KEEP SKIES
GENERALLY WITH PRECIPITATION LIMITED TO A FEW PASSING SHOWERS. A
WEAK FRONT WILL THEN APPROACH THE KUSKOKWIM DELTA ON
TUESDAY...BRINGING A CHANCE OF RAIN TO THE AREAS. RIDGING WILL
HOWEVER REMAIN OVER THE KUSKOKWIM VALLEY AND BRISTOL BAY...KEEPING
THE AREA DRY WITH LIGHT WINDS INTO MID WEEK.

&&

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

AFTER A WEAKENING AREA OF RAIN AND SNOW SHOWERS FROM THE PRIBILOF
ISLANDS INTO THE AKPENN DISSIPATES LATE TONIGHT...THE WEATHER WILL
QUICKLY BECOME DOMINATED BY A FRONTAL SYSTEM CURRENTLY ENTERING
THE WESTERN ALEUTIANS. THIS SYSTEM WILL BECOME A LOW COMPLEX WITH
MULTIPLE CENTERS OVER THE WESTERN BERING BY MONDAY AFTERNOON. WITH
CONSIDERABLE MODEL DISAGREEMENT WITH BOTH THE LOCATION AND
INTENSITY OF THESE LOWS...FORECAST CONFIDENCE QUICKLY DIMINISHES
WITH A DEVELOPING LOW APPROACHING THE EASTERN ALEUTIANS TUESDAY.
IT DOES APPEAR THAT THIS SETUP WILL KEEP WET WEATHER OVER THE
BERING WITH A POTENTIAL FOR GALE FORCE WINDS IN THE EASTERN
ALEUTIANS BY WEDNESDAY.


&&

.LONG TERM FORECAST (DAYS 4 THROUGH 7)...
THE OUTCOME OF THE LONG TERM FORECAST REMAINS HIGHLY DEPENDENT
THE TRACK AND STRENGTH OF THE COMPLEX LOW AS IT BEGINS TO
CONSOLIDATE OVER THE BERING SEA WEDNESDAY. GLOBAL MODELS CONTINUE
TO STRUGGLE WITH THE DETAILS OF THIS SYSTEM...KEEPING FORECAST
CONFIDENCE LOW IN THE TIMING AND STRENGTH OF THE ASSOCIATED
FRONTAL SYSTEM AS IT PROGRESSES EASTWARD. THE MORE NORTHERLY GFS
SOLUTION IS SLOWER TO CONSOLIDATE THE LOW OVER THE NORTHERN
BERING...BUT QUICKEST WITH BRINGING FRONTAL WINDS AND
PRECIPITATION TO THE CENTRAL ALEUTIANS WEDNESDAY MORNING AND
EVENTUALLY INTO THE SOUTHWEST COAST THURSDAY MORNING. THE MORE
SOUTHERLY ECMWF SOLUTION CONSOLIDATES THE LOW QUICKER OVER THE
SOUTHERN BERING...BUT IS SLOWER TO BRING THE FRONTAL WINDS AND
PRECIPITATION INTO THE CENTRAL ALEUTIANS WEDNESDAY AFTERNOON AND
EVENTUALLY INTO THE SOUTHWEST COAST THURSDAY AFTERNOON.

GLOBAL GUIDANCE HAS BEEN SIGNALING THAT THIS ACTIVITY OUT WEST
WILL AMPLIFY A RIDGE OF HIGH PRESSURE IN THE GULF WHICH WILL ACT
TO SLOW THE PROGRESSION OF THIS PATTERN...AND WILL KEEP
SOUTHCENTRAL ALASKA DRY THROUGH THE END OF THE WEEK. EXPECT
SLIGHTLY ABOVE NORMAL TEMPERATURES AND LIGHT WINDS FOR THE WEEK.
CONFIDENCE BEGINS TO DIMINISH INTO THE WEEKEND...WHERE THE
LONGEVITY OF THIS PATTERN BECOMES HIGHLY DEPENDENT ON WHICH MODEL
SOLUTION VERIFIES. A MORE SOUTHERLY SOLUTION (ECMWF) REGARDING
THE LOW OUT WEST WOULD FAVOR DRIER CONDITIONS PERSISTING THROUGH
MUCH OF THE WEEKEND....WHEREAS THE MORE NORTHERLY SOLUTION (GFS)
DEAMPLIFIES THE RIDGE QUICKER AND BRINGS A WEAK SHORTWAVE THROUGH
SOUTHCENTRAL ON SUNDAY.

&&

.AFC WATCHES/WARNINGS/ADVISORIES...
PUBLIC...NONE.
MARINE...NONE.
FIRE WEATHER...NONE.

&&

$$




000
FXAK68 PAFC 231324
AFDAFC

SOUTHCENTRAL AND SOUTHWEST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE ANCHORAGE AK
424 AM AKST SUN NOV 23 2014

.ANALYSIS AND UPPER LEVELS...

A LARGE STACKED UPPER LEVEL LOW CONTINUES TO SPIN IN VICINITY OF
THE SHUMAGIN ISLANDS THIS MORNING JUST TO THE SOUTH OF THE ALASKA
PENINSULA. WATER VAPOR AND INFRARED IMAGERY INDICATE A FAIRLY
UNSTABLE REGIME TO THE NORTHEAST THROUGH SOUTH OF THE LOW PRESSURE
CIRCULATION FROM SOUTHCENTRAL THROUGH THE GULF OF ALASKA
GENERATING SCATTERED TO NUMEROUS SNOW SHOWERS.

OUT WEST...A PAIR OF SHORTWAVE RIDGES MAKE UP THE GENERAL
RIDGINESS OVER THE NORTHERN AND WESTERN BERING SEA. A STRONG LOW
PRESSURE SYSTEM NEAR KAMCHATKA IS BEGINNING TO STRENGTHEN AS IT
BEGINS TO SLOWLY MOVE EAST TOWARD THE WESTERN BERING SEA.

&&

.MODEL DISCUSSION...

MODELS ARE IN GENERALLY GOOD AGREEMENT SYNOPTICALLY. THEY ALL TAKE
THE SHUMAGIN ISLANDS OCCLUDED LOW AND DRIFT IT EAST INTO THE
CENTRAL GULF BY LATE MONDAY INTO TUESDAY...MAKING IT BROAD AND
DIFFUSE IN THE PROCESS. MODELS DIFFER SOMEWHAT IN ITS DEPICTION IN
THE GULF BUT WITH NO SIGNIFICANT IMPACT ON THE FORECAST.

OUT IN THE FAR WEST...THE KAMCHATKA LOW CONTINUES TO STRENGTHEN
AND MATURE INTO A STRONG CYCLONE CENTERED NORTH AND WEST OF ATTU
THROUGH MON NIGHT. A LOW PRESSURE SYSTEM WILL STRENGTHEN ALONG ITS
ASSOCIATED FRONT AS IT MOVES INTO THE WESTERN ALEUTIANS LATE
SUNDAY INTO MONDAY...THEN CIRCLE BACK TOWARD BACK TOWARD THE
PARENT LOW AND MERGE WITH IT LATE MONDAY INTO TUESDAY NORTH AND
WEST OF ATTU.

THE IMPACT OF THE STRONG LOW PRESSURE SYSTEM BECOMING STATIONARY
OVER THE FAR WESTERN BERING LATE MONDAY INTO MID-WEEK WILL RESULT
IN HIGH PRESSURE RIDGING STRENGTHENING ALOFT OVER THE MAINLAND
TUESDAY INTO WEDNESDAY.

&&

.SHORT TERM FORECAST SOUTHCENTRAL ALASKA (DAYS 1 AND 2)...
A SERIES OF UPPER LEVEL DISTURBANCES MOVING NORTHWARD ACROSS THE
GULF OF ALASKA TO SOUTHCENTRAL CONTINUE TO PROVIDE QUITE THE
CHALLENGE FOR THE PRECIPITATION FORECAST. FOR THE MOST PART SHOWERS
ASSOCIATED WITH THESE DISTURBANCES HAVE BEEN CONFINED TO THE GULF
COASTAL REGION WITH VERY FEW SHOWERS MAKING IT OVER THE COASTAL
MOUNTAINS. THIS IS DUE TO WEAK DOWNSLOPE FLOW AND LOW LEVEL DRY
AIR SUPPORTED BY OFFSHORE FLOW AT THE SURFACE. HOWEVER...THERE
HAVE BEEN A FEW STRONGER UPPER WAVES (ONE OF WHICH IS MOVING
THROUGH THIS MORNING) WHICH TEMPORARILY MODIFY THE LOW LEVEL FLOW
(TO WEAKEN DOWNSLOPING). PINPOINTING THE LOCATION AND AMOUNT OF
PRECIP IS VERY DIFFICULT...ESPECIALLY SINCE NONE OF THE MODELS
HAVE A GREAT HANDLE ON THE PLACEMENT AND TIMING OF INDIVIDUAL
FEATURES. SATELLITE AND RADAR TRENDS ARE THE MOST USEFUL TOOL IN
THIS SITUATION. BECAUSE OF THIS...FORECAST CONFIDENCE IN THE
PRECIP FORECAST BEYOND THE FIRST SIX HOURS IS LOW.

THE AIR MASS ACROSS THE REGION HAS CONTINUED A STEADY COOLING
TREND. THE IMMEDIATE COAST REMAINS ALL RAIN...BUT INTERIOR
PORTIONS OF WESTERN PRINCE WILLIAM SOUND HAVE SEEN SOME PERIODS OF
SNOW OR RAIN AND SNOW MIXED WITH VERY MINOR SNOW ACCUMULATIONS.
AS PER THE ANCHORAGE SOUNDING ANYTHING ON THE LEE SIDE OF THE
COASTAL RANGE WILL FALL AS SNOW.

UPPER LEVEL FLOW WILL SHIFT SUNDAY NIGHT INTO MONDAY AS THE LOW
ALONG THE ALASKA PENINSULA EXITS EASTWARD ACROSS THE GULF AND
UPPER FLOW OVER SOUTHCENTRAL BECOMES WESTERLY. PRECIP WILL THEN
BECOME FAVORED ALONG THE WEST SLOPES OF MOUNTAINS WHILE PRECIP IN
WESTERN PRINCE WILLIAM SOUND WILL DIMINISH.

&&

.SHORT TERM FORECAST SOUTHWEST ALASKA (DAYS 1 THROUGH 3)...
ISOLATED TO SCATTERED SNOW SHOWERS WILL CONTINUE TO DEVELOP TODAY ALONG
A WEAK STATIONARY BOUNDARY ACROSS BRISTOL BAY. WITH TEMPERATURES
NEAR FREEZING ALONG THE EASTERN ALASKA PENINSULA AND ALEUTIAN
RANGE AND BELOW FREEZING TEMPERATURES TO THE NORTH...ISOLATED
POCKETS OF FREEZING RAIN ARE POSSIBLE MAINLY SOUTH AND EAST OF
DILLINGHAM. SCATTERED SNOW SHOWERS WILL MAKE IT INTO THE ALASKA
RANGE TODAY AS THE BROAD AREA OF LOW PRESSURE PUSHES A SHORTWAVE
WESTWARD. ISOLATED TO SCATTERED PRECIPITATION DIMINISHES MONDAY
NIGHT AS THE MAIN LOW CENTER SHIFTS EAST. THE NEXT FRONT PUSHES
INTO THE EASTERN BERING ON TUESDAY BRINGING INCREASED RAIN CHANCES
FOR RAIN AND GUSTY WINDS ALONG THE ALASKA PENINSULA AND WESTERN
COAST.

&&

.SHORT TERM FORECAST BERING SEA/ALEUTIANS (DAYS 1 THROUGH 3)...
NORTHERLY FLOW WITH ISOLATED TO SCATTERED SHOWERS CONTINUE ACROSS
THE BERING TODAY. LOW PRESSURE EAST OF THE KAMCHATKA PENINSULA
WILL PUSH A WARM FRONT INTO THE WESTERN ALEUTIANS THIS AFTERNOON
BRINGING STRONG WINDS AND RAIN THROUGH TONIGHT. THE BOUNDARY MOVES
INTO CENTRAL BERING/EASTERN ALEUTIANS BY TUESDAY MORNING AND THEN
REMAINS STATIONARY AS THE LOW FILLS. ANOTHER LOW WILL MOVE UP FROM
THE NORTH PACIFIC WITH ANOTHER ROUND OF PRECIPITATION MID WEEK.


&&

.LONG TERM FORECAST (DAYS 3 THROUGH 7)...
THE EXTENDED FORECAST LOOKS MUCH THE SAME TODAY AND WILL STILL BE
DEPENDENT ON A COMPLEX LOW SETTING UP SHOP IN THE WESTERN/CENTRAL
BERING SEA. A CURRENTLY DEVELOPING KAMCHATKA LOW WILL ANCHOR THE
LONGWAVE PATTERN WHILE SEVERAL COMPACT SHORTWAVE TROUGHS WILL
DEVELOP AND JOIN THE LARGE SCALE CIRCULATION. THE FIRST WILL
STRENGTHEN ALONG THE FRONTAL BOUNDARY PROGRESSING EASTWARD ACROSS
THE CHAIN IN THE VICINITY OF THE CENTRAL/EASTERN ALEUTIANS
BRINGING RAIN AND GALE FORCE WINDS. ANOTHER WAVE QUICKLY FOLLOWS
BY WEDNESDAY REINFORCING THE CIRCULATION AND BRINGING MORE RAIN
AND WIND TO THE CENTRAL ALEUTIANS WHILE SENDING THE FRONT FURTHER
EAST IN THE BERING SEA. GLOBAL GUIDANCE HAS BEEN SIGNALING THAT
THIS ACTIVITY OUT WEST WILL PUMP UP A RIDGE OF HIGH PRESSURE IN
THE GULF WHICH WILL ACT TO SLOW THE PROGRESSION OF THE PATTERN AND
KEEP THE SOUTHCENTRAL DRY FOR THE FORESEEABLE FUTURE. EXPECT
SLIGHTLY ABOVE NORMAL TEMPERATURES AND LIGHT WINDS FOR THE WEEK.

&&


.AFC WATCHES/WARNINGS/ADVISORIES...
PUBLIC...NONE.
MARINE...HEAVY FREEZING SPRAY 181.
         GALE 175 176 177 178 185.
FIRE WEATHER...NONE.

&&

$$

SYNOPSIS AND MODEL DISCUSSION...CC
SOUTHCENTRAL ALASKA...SEB
SOUTHWEST ALASKA/BERING SEA/ALEUTIANS...KH
LONG TERM...MTL




000
FXAK68 PAFC 231324
AFDAFC

SOUTHCENTRAL AND SOUTHWEST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE ANCHORAGE AK
424 AM AKST SUN NOV 23 2014

.ANALYSIS AND UPPER LEVELS...

A LARGE STACKED UPPER LEVEL LOW CONTINUES TO SPIN IN VICINITY OF
THE SHUMAGIN ISLANDS THIS MORNING JUST TO THE SOUTH OF THE ALASKA
PENINSULA. WATER VAPOR AND INFRARED IMAGERY INDICATE A FAIRLY
UNSTABLE REGIME TO THE NORTHEAST THROUGH SOUTH OF THE LOW PRESSURE
CIRCULATION FROM SOUTHCENTRAL THROUGH THE GULF OF ALASKA
GENERATING SCATTERED TO NUMEROUS SNOW SHOWERS.

OUT WEST...A PAIR OF SHORTWAVE RIDGES MAKE UP THE GENERAL
RIDGINESS OVER THE NORTHERN AND WESTERN BERING SEA. A STRONG LOW
PRESSURE SYSTEM NEAR KAMCHATKA IS BEGINNING TO STRENGTHEN AS IT
BEGINS TO SLOWLY MOVE EAST TOWARD THE WESTERN BERING SEA.

&&

.MODEL DISCUSSION...

MODELS ARE IN GENERALLY GOOD AGREEMENT SYNOPTICALLY. THEY ALL TAKE
THE SHUMAGIN ISLANDS OCCLUDED LOW AND DRIFT IT EAST INTO THE
CENTRAL GULF BY LATE MONDAY INTO TUESDAY...MAKING IT BROAD AND
DIFFUSE IN THE PROCESS. MODELS DIFFER SOMEWHAT IN ITS DEPICTION IN
THE GULF BUT WITH NO SIGNIFICANT IMPACT ON THE FORECAST.

OUT IN THE FAR WEST...THE KAMCHATKA LOW CONTINUES TO STRENGTHEN
AND MATURE INTO A STRONG CYCLONE CENTERED NORTH AND WEST OF ATTU
THROUGH MON NIGHT. A LOW PRESSURE SYSTEM WILL STRENGTHEN ALONG ITS
ASSOCIATED FRONT AS IT MOVES INTO THE WESTERN ALEUTIANS LATE
SUNDAY INTO MONDAY...THEN CIRCLE BACK TOWARD BACK TOWARD THE
PARENT LOW AND MERGE WITH IT LATE MONDAY INTO TUESDAY NORTH AND
WEST OF ATTU.

THE IMPACT OF THE STRONG LOW PRESSURE SYSTEM BECOMING STATIONARY
OVER THE FAR WESTERN BERING LATE MONDAY INTO MID-WEEK WILL RESULT
IN HIGH PRESSURE RIDGING STRENGTHENING ALOFT OVER THE MAINLAND
TUESDAY INTO WEDNESDAY.

&&

.SHORT TERM FORECAST SOUTHCENTRAL ALASKA (DAYS 1 AND 2)...
A SERIES OF UPPER LEVEL DISTURBANCES MOVING NORTHWARD ACROSS THE
GULF OF ALASKA TO SOUTHCENTRAL CONTINUE TO PROVIDE QUITE THE
CHALLENGE FOR THE PRECIPITATION FORECAST. FOR THE MOST PART SHOWERS
ASSOCIATED WITH THESE DISTURBANCES HAVE BEEN CONFINED TO THE GULF
COASTAL REGION WITH VERY FEW SHOWERS MAKING IT OVER THE COASTAL
MOUNTAINS. THIS IS DUE TO WEAK DOWNSLOPE FLOW AND LOW LEVEL DRY
AIR SUPPORTED BY OFFSHORE FLOW AT THE SURFACE. HOWEVER...THERE
HAVE BEEN A FEW STRONGER UPPER WAVES (ONE OF WHICH IS MOVING
THROUGH THIS MORNING) WHICH TEMPORARILY MODIFY THE LOW LEVEL FLOW
(TO WEAKEN DOWNSLOPING). PINPOINTING THE LOCATION AND AMOUNT OF
PRECIP IS VERY DIFFICULT...ESPECIALLY SINCE NONE OF THE MODELS
HAVE A GREAT HANDLE ON THE PLACEMENT AND TIMING OF INDIVIDUAL
FEATURES. SATELLITE AND RADAR TRENDS ARE THE MOST USEFUL TOOL IN
THIS SITUATION. BECAUSE OF THIS...FORECAST CONFIDENCE IN THE
PRECIP FORECAST BEYOND THE FIRST SIX HOURS IS LOW.

THE AIR MASS ACROSS THE REGION HAS CONTINUED A STEADY COOLING
TREND. THE IMMEDIATE COAST REMAINS ALL RAIN...BUT INTERIOR
PORTIONS OF WESTERN PRINCE WILLIAM SOUND HAVE SEEN SOME PERIODS OF
SNOW OR RAIN AND SNOW MIXED WITH VERY MINOR SNOW ACCUMULATIONS.
AS PER THE ANCHORAGE SOUNDING ANYTHING ON THE LEE SIDE OF THE
COASTAL RANGE WILL FALL AS SNOW.

UPPER LEVEL FLOW WILL SHIFT SUNDAY NIGHT INTO MONDAY AS THE LOW
ALONG THE ALASKA PENINSULA EXITS EASTWARD ACROSS THE GULF AND
UPPER FLOW OVER SOUTHCENTRAL BECOMES WESTERLY. PRECIP WILL THEN
BECOME FAVORED ALONG THE WEST SLOPES OF MOUNTAINS WHILE PRECIP IN
WESTERN PRINCE WILLIAM SOUND WILL DIMINISH.

&&

.SHORT TERM FORECAST SOUTHWEST ALASKA (DAYS 1 THROUGH 3)...
ISOLATED TO SCATTERED SNOW SHOWERS WILL CONTINUE TO DEVELOP TODAY ALONG
A WEAK STATIONARY BOUNDARY ACROSS BRISTOL BAY. WITH TEMPERATURES
NEAR FREEZING ALONG THE EASTERN ALASKA PENINSULA AND ALEUTIAN
RANGE AND BELOW FREEZING TEMPERATURES TO THE NORTH...ISOLATED
POCKETS OF FREEZING RAIN ARE POSSIBLE MAINLY SOUTH AND EAST OF
DILLINGHAM. SCATTERED SNOW SHOWERS WILL MAKE IT INTO THE ALASKA
RANGE TODAY AS THE BROAD AREA OF LOW PRESSURE PUSHES A SHORTWAVE
WESTWARD. ISOLATED TO SCATTERED PRECIPITATION DIMINISHES MONDAY
NIGHT AS THE MAIN LOW CENTER SHIFTS EAST. THE NEXT FRONT PUSHES
INTO THE EASTERN BERING ON TUESDAY BRINGING INCREASED RAIN CHANCES
FOR RAIN AND GUSTY WINDS ALONG THE ALASKA PENINSULA AND WESTERN
COAST.

&&

.SHORT TERM FORECAST BERING SEA/ALEUTIANS (DAYS 1 THROUGH 3)...
NORTHERLY FLOW WITH ISOLATED TO SCATTERED SHOWERS CONTINUE ACROSS
THE BERING TODAY. LOW PRESSURE EAST OF THE KAMCHATKA PENINSULA
WILL PUSH A WARM FRONT INTO THE WESTERN ALEUTIANS THIS AFTERNOON
BRINGING STRONG WINDS AND RAIN THROUGH TONIGHT. THE BOUNDARY MOVES
INTO CENTRAL BERING/EASTERN ALEUTIANS BY TUESDAY MORNING AND THEN
REMAINS STATIONARY AS THE LOW FILLS. ANOTHER LOW WILL MOVE UP FROM
THE NORTH PACIFIC WITH ANOTHER ROUND OF PRECIPITATION MID WEEK.


&&

.LONG TERM FORECAST (DAYS 3 THROUGH 7)...
THE EXTENDED FORECAST LOOKS MUCH THE SAME TODAY AND WILL STILL BE
DEPENDENT ON A COMPLEX LOW SETTING UP SHOP IN THE WESTERN/CENTRAL
BERING SEA. A CURRENTLY DEVELOPING KAMCHATKA LOW WILL ANCHOR THE
LONGWAVE PATTERN WHILE SEVERAL COMPACT SHORTWAVE TROUGHS WILL
DEVELOP AND JOIN THE LARGE SCALE CIRCULATION. THE FIRST WILL
STRENGTHEN ALONG THE FRONTAL BOUNDARY PROGRESSING EASTWARD ACROSS
THE CHAIN IN THE VICINITY OF THE CENTRAL/EASTERN ALEUTIANS
BRINGING RAIN AND GALE FORCE WINDS. ANOTHER WAVE QUICKLY FOLLOWS
BY WEDNESDAY REINFORCING THE CIRCULATION AND BRINGING MORE RAIN
AND WIND TO THE CENTRAL ALEUTIANS WHILE SENDING THE FRONT FURTHER
EAST IN THE BERING SEA. GLOBAL GUIDANCE HAS BEEN SIGNALING THAT
THIS ACTIVITY OUT WEST WILL PUMP UP A RIDGE OF HIGH PRESSURE IN
THE GULF WHICH WILL ACT TO SLOW THE PROGRESSION OF THE PATTERN AND
KEEP THE SOUTHCENTRAL DRY FOR THE FORESEEABLE FUTURE. EXPECT
SLIGHTLY ABOVE NORMAL TEMPERATURES AND LIGHT WINDS FOR THE WEEK.

&&


.AFC WATCHES/WARNINGS/ADVISORIES...
PUBLIC...NONE.
MARINE...HEAVY FREEZING SPRAY 181.
         GALE 175 176 177 178 185.
FIRE WEATHER...NONE.

&&

$$

SYNOPSIS AND MODEL DISCUSSION...CC
SOUTHCENTRAL ALASKA...SEB
SOUTHWEST ALASKA/BERING SEA/ALEUTIANS...KH
LONG TERM...MTL





000
FXAK68 PAFC 230650
AFDAFC

SOUTHCENTRAL AND SOUTHWEST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE ANCHORAGE AK
950 PM AKST SAT NOV 22 2014

UPDATE (945 PM)...

SATELLITE TRENDS SEEM TO BE CORROBORATING 00Z NAM AND GFS MODEL
TRENDS IN DEPICTING INCREASED POTENTIAL FOR A BRIEF BURST OF SNOW
TO IMPACT THE ANCHORAGE AND NEIGHBORING COMMUNITIES LATER
TONIGHT...MAINLY BETWEEN MIDNIGHT AND 4 AM. DUE TO THE QUICK
MOVEMENT OF THE SYSTEM...SNOW ACCUMULATIONS SHOULD BE NO MORE THAN
AN INCH OR SO AT MOST BUT COULD BE IMPACTFUL FOR THE EARLY SUNDAY
MORNING TRAVEL INTERESTS GIVEN THE SNOW-FREE CONDITIONS CURRENTLY.

&&

.PREV DISCUSSION... /ISSUED 435 PM AKST SAT NOV 22 2014/

ANALYSIS AND UPPER LEVELS...

A STACKED AND WEAKENING 970S LOW CENTER JUST WEST OF SAND POINT
IS SLOWLY DRIFTING ESE AND WEAKENING. RAIN AND SHOWERS ASSOCIATED
WITH THIS FEATURE WERE OBSERVED OVER THE AK PENINSULA. BRISK
NORTHERLY WINDS AND SHOWERS WERE EVIDENT ON THE BACKSIDE OF THE
CENTER OVER THE CENTRAL AND EASTERN ALEUTIANS. AN UPPER LEVEL WAVE
AND WEAK SURFACE REFLECTION JUST SOUTH OF WESTERN PRINCE WILLIAM
SOUND WAS MOVING NORTH AND WEST. RADAR IMAGERY SHOWERS ENHANCED
RETURNS HEADING TOWARD THE EASTERN KENAI PENINSULA WITH RAIN AND
SHOWERS REPORTED AT STATIONS THIS AFTERNOON. TEMPS ALONG THE GULF
COAST...BRISTOL BAY...AND AK PEN/ALEUTIANS CONTINUED FAIRLY MILD.
WEAK COLD ADVECTION WITH OFFSHORE FLOW DROPPED TEMPS OVER THE
DELTA INTO THE TEENS. COLDEST TEMPS ACROSS THE FORECAST AREA WERE
STILL IN THE COPPER RIVER BASIN WITH VALUES FROM -2 TO SINGLE
DIGITS ABOVE IN LOW LYING AREAS.

MODEL DISCUSSION(SHORT TERM)...
MODELS INITIALIZED FAIRLY WELL THIS MORNING. FORECAST TRENDS ARE
IN GOOD AGREEMENT THROUGH THE SHORT TERM. THE GEM REGIONAL WAS
USED IN THE WEST DURING THE EARLY PART OF THE SHORT TERM WITH A
TRANSITION INTO A NAM/EC BLEND FOR THE REMAINDER. IN THE
EAST...THE NAM WILL BE USED EARLY ON FOLLOWED BY A TRANSITION TO A
NAM/EC BLEND.

SHORT TERM FORECAST SOUTHCENTRAL ALASKA (DAYS 1 AND 2)...
A DISSIPATING FRONT ALONG THE NORTH GULF COAST AND A SERIES OF
WEAK DISTURBANCES ROTATING THROUGH THE GULF WILL KEEP SHOWER
ACTIVITY FOCUSED MAINLY ALONG THE COAST THROUGH MONDAY. THE FIRST
OF THESE UPPER WAVES WILL HELP TO SPREAD SNOW SHOWERS OVER INLAND
PORTIONS OF THE AREA TONIGHT AS DOWNSLOPE FLOW WEAKENS...ALTHOUGH
DRY AIR AT THE SURFACE WILL KEEP THESE SHOWERS FAIRLY LIMITED IN
COVERAGE. ANOTHER WAVE WILL THEN MOVE THROUGH LATER SUNDAY AND
PROVIDE ANOTHER SHOT OF ENHANCED SHOWER ACTIVITY. SHOWERS WILL
BEGIN TO DIMINISH ACROSS THE AREA MONDAY NIGHT INTO TUESDAY AS THE
LOW CURRENTLY OVER THE ALASKA PENINSULA WEAKENS INTO AN OPEN
TROUGH AND MOVES EAST OF THE AREA.

SHORT TERM FORECAST SOUTHWEST ALASKA (DAYS 1 THROUGH 3)...
WITH THE EXCEPTION OF SOUTHERN BRISTOL BAY...MOST OF THE SOUTHWEST
MAINLAND WILL REMAIN UNDER PARTLY TO MOSTLY CLOUDY SKIES THROUGH
THE END OF THE WEEKEND. ISOLATED TO SCATTERED RAIN/SNOW SHOWERS
MAY FORM IN THE AREA ON SUNDAY AS A WEAK ELONGATED UPPER LEVEL
TROUGH DEVELOPS...HOWEVER THESE SHOULD LARGELY BE LIMITED TO
SOUTHERN BRISTOL BAY. TEMPERATURES ARE EXPECTED TO FALL INTO THE
SINGLE DIGITS OVER IN NEXT FEW NIGHTS IN THE KUSKOKWIM VALLEY AND
INLAND BRISTOL BAY AS THE LOW NEAR THE AKPENN CONTINUES TO SLOWLY
WEAKEN...AND WEAK RIDGING BEINGS TO DEVELOP. THESE TEMPERATURES
WILL THEN CONTINUE UNDER MOSTLY CLEAR SKIES UNTIL TUESDAY WHEN A
WEAK FRONT SLIDES ONSHORE FROM THE BERING.

SHORT TERM FORECAST BERING SEA/ALEUTIANS (DAYS 1 THROUGH 3)...

THE LOW CENTERED JUST SOUTH OF THE AKPENN WILL CONTINUE TO BRING
SNOW SHOWERS TO THE BERING...BECOMING RAIN SHOWERS TOWARDS THE
ALEUTIAN ISLANDS THROUGH THIS WEEKEND. THE GUSTY NORTHWESTERLY
WINDS ACCOMPANYING THESE SHOWERS WILL SLOWLY DIMINISH THIS
WEEKEND...THEN DISSIPATE ON MONDAY AS RIDING BEGINS TO TAKE OVER.
A FRONTAL SYSTEM ASSOCIATED WITH AN LOW LOCATED OFF THE KAMCHATKA
PENINSULA COAST WILL BEGIN TO IMPACT THE WESTERN ALEUTIANS WITH
RAIN AND GALE FORCE WINDS ON SUNDAY EVENING. THIS SYSTEM WILL THEN
MOVE THROUGH THE BERING AS IT SLOWLY DISSIPATES THROUGH MONDAY.

LONG TERM FORECAST (DAYS 3 THROUGH 7)...
A WEAK LOW OVER THE WESTERN GULF WILL CONTINUE TO WEAKEN AS IT
DRIFTS EASTWARD...KEEPING MOST OF THE SHOWER ACTIVITY CONFINED TO
THE NORTH GULF COAST AND KODIAK ISLAND BEFORE DISSIPATING ON
TUESDAY. UPPER LEVEL RIDGING OVER THE EASTERN ALEUTIANS WILL BEGIN
TO AMPLIFY AND SLIDE EASTWARD OVER THE SOUTHWEST MAINLAND AND
SOUTHCENTRAL ALASKA BY TUESDAY AFTERNOON. THIS WILL BRING IN SOME
DRIER CONDITIONS TO THE INTERIOR SOUTHWEST MAINLAND THROUGH
WEDNESDAY MORNING...AND TO SOUTHCENTRAL ALASKA THROUGH WEDNESDAY
EVENING. EVEN THOUGH CURRENT GUIDANCE IS IN GOOD AGREEMENT WITH
A BLOCKING RIDGE SETTING UP OVER THE EASTERN DOMAIN BY MID
WEEK...THE MODELS CONTINUE TO STRUGGLE WITH THE TIMING AND
STRENGTH OF SMALLER SCALE DISTURBANCES AND LOW POSITIONING OVER
THE WESTERN DOMAIN THROUGH MUCH OF THE LONG TERM. GLOBAL MODELS
AND WPC GUIDANCE ARE GETTING CLOSER TO A COMMON SOLUTION REGARDING
THE TRIPLE POINT LOW DEVELOPING OVER THE NORTH PACIFIC TUESDAY
AFTERNOON...BUT CONTINUE TO QUICKLY DIVERGE FROM THAT SOLUTION BY
TUESDAY NIGHT. MODELS TYPICALLY STRUGGLE WITH THIS TYPE OF
DEVELOPMENT...WHICH HAS CREATED HIGHER UNCERTAINTY WITH REGARDS TO
THE TIMING/STRENGTH OF WINDS AND PRECIPITATION THAT CAN IMPACT THE
ALASKA PENINSULA AND SOUTHWEST MAINLAND STARTING TUESDAY NIGHT.
FURTHER WEST...A DEVELOPING LOW EAST OF THE KAMCHATKA PENINSULA
WILL BEGIN TO PHASE WITH ANOTHER LOW PRESSURE SYSTEM TO THE SOUTH
ON TUESDAY...AND TRACK OVER THE WESTERN ALEUTIANS ON WEDNESDAY.
THE FRONT ASSOCIATED WITH THIS COMPLEX SYSTEM WILL TRACK ACROSS
THE ALEUTIANS FROM WEST TO EAST...BRINGING WET AND GUSTY
CONDITIONS TO MUCH OF THE ALEUTIANS AND BERING THROUGH THURSDAY
EVENING. CONDITIONS WILL BECOME MORE SHOWERY OVER MUCH OF THE
BERING AND ALEUTIAN CHAIN THROUGH FRIDAY NIGHT...AS THE LOW
WEAKENS AND TRACKS EASTWARD.

AFC WATCHES/WARNINGS/ADVISORIES...
PUBLIC...NONE.
MARINE...NONE.
FIRE WEATHER...NONE.


&&

.AFC WATCHES/WARNINGS/ADVISORIES...
PUBLIC...NONE.
MARINE...NONE.
FIRE WEATHER...NONE.

&&

$$

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




000
FXAK68 PAFC 230135
AFDAFC

SOUTHCENTRAL AND SOUTHWEST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE ANCHORAGE AK
435 PM AKST SAT NOV 22 2014

.ANALYSIS AND UPPER LEVELS...

A STACKED AND WEAKENING 970S LOW CENTER JUST WEST OF SAND POINT
IS SLOWLY DRIFTING ESE AND WEAKENING. RAIN AND SHOWERS ASSOCIATED
WITH THIS FEATURE WERE OBSERVED OVER THE AK PENINSULA. BRISK
NORTHERLY WINDS AND SHOWERS WERE EVIDENT ON THE BACKSIDE OF THE
CENTER OVER THE CENTRAL AND EASTERN ALEUTIANS. AN UPPER LEVEL WAVE
AND WEAK SURFACE REFLECTION JUST SOUTH OF WESTERN PRINCE WILLIAM
SOUND WAS MOVING NORTH AND WEST. RADAR IMAGERY SHOWERS ENHANCED
RETURNS HEADING TOWARD THE EASTERN KENAI PENINSULA WITH RAIN AND
SHOWERS REPORTED AT STATIONS THIS AFTERNOON. TEMPS ALONG THE GULF
COAST...BRISTOL BAY...AND AK PEN/ALEUTIANS CONTINUED FAIRLY MILD.
WEAK COLD ADVECTION WITH OFFSHORE FLOW DROPPED TEMPS OVER THE
DELTA INTO THE TEENS. COLDEST TEMPS ACROSS THE FORECAST AREA WERE
STILL IN THE COPPER RIVER BASIN WITH VALUES FROM -2 TO SINGLE
DIGITS ABOVE IN LOW LYING AREAS.

&&

.MODEL DISCUSSION(SHORT TERM)...
MODELS INITIALIZED FAIRLY WELL THIS MORNING. FORECAST TRENDS ARE
IN GOOD AGREEMENT THROUGH THE SHORT TERM. THE GEM REGIONAL WAS
USED IN THE WEST DURING THE EARLY PART OF THE SHORT TERM WITH A
TRANSITION INTO A NAM/EC BLEND FOR THE REMAINDER. IN THE
EAST...THE NAM WILL BE USED EARLY ON FOLLOWED BY A TRANSITION TO A
NAM/EC BLEND.

&&

.SHORT TERM FORECAST SOUTHCENTRAL ALASKA (DAYS 1 AND 2)...
A DISSIPATING FRONT ALONG THE NORTH GULF COAST AND A SERIES OF
WEAK DISTURBANCES ROTATING THROUGH THE GULF WILL KEEP SHOWER
ACTIVITY FOCUSED MAINLY ALONG THE COAST THROUGH MONDAY. THE FIRST
OF THESE UPPER WAVES WILL HELP TO SPREAD SNOW SHOWERS OVER INLAND
PORTIONS OF THE AREA TONIGHT AS DOWNSLOPE FLOW WEAKENS...ALTHOUGH
DRY AIR AT THE SURFACE WILL KEEP THESE SHOWERS FAIRLY LIMITED IN
COVERAGE. ANOTHER WAVE WILL THEN MOVE THROUGH LATER SUNDAY AND
PROVIDE ANOTHER SHOT OF ENHANCED SHOWER ACTIVITY. SHOWERS WILL
BEGIN TO DIMINISH ACROSS THE AREA MONDAY NIGHT INTO TUESDAY AS THE
LOW CURRENTLY OVER THE ALASKA PENINSULA WEAKENS INTO AN OPEN
TROUGH AND MOVES EAST OF THE AREA.

&&

.SHORT TERM FORECAST SOUTHWEST ALASKA (DAYS 1 THROUGH 3)...
WITH THE EXCEPTION OF SOUTHERN BRISTOL BAY...MOST OF THE SOUTHWEST
MAINLAND WILL REMAIN UNDER PARTLY TO MOSTLY CLOUDY SKIES THROUGH
THE END OF THE WEEKEND. ISOLATED TO SCATTERED RAIN/SNOW SHOWERS
MAY FORM IN THE AREA ON SUNDAY AS A WEAK ELONGATED UPPER LEVEL
TROUGH DEVELOPS...HOWEVER THESE SHOULD LARGELY BE LIMITED TO
SOUTHERN BRISTOL BAY. TEMPERATURES ARE EXPECTED TO FALL INTO THE
SINGLE DIGITS OVER IN NEXT FEW NIGHTS IN THE KUSKOKWIM VALLEY AND
INLAND BRISTOL BAY AS THE LOW NEAR THE AKPENN CONTINUES TO SLOWLY
WEAKEN...AND WEAK RIDGING BEINGS TO DEVELOP. THESE TEMPERATURES
WILL THEN CONTINUE UNDER MOSTLY CLEAR SKIES UNTIL TUESDAY WHEN A
WEAK FRONT SLIDES ONSHORE FROM THE BERING.

&&

.SHORT TERM FORECAST BERING SEA/ALEUTIANS (DAYS 1 THROUGH 3)...

THE LOW CENTERED JUST SOUTH OF THE AKPENN WILL CONTINUE TO BRING
SNOW SHOWERS TO THE BERING...BECOMING RAIN SHOWERS TOWARDS THE
ALEUTIAN ISLANDS THROUGH THIS WEEKEND. THE GUSTY NORTHWESTERLY
WINDS ACCOMPANYING THESE SHOWERS WILL SLOWLY DIMINISH THIS
WEEKEND...THEN DISSIPATE ON MONDAY AS RIDING BEGINS TO TAKE OVER.
A FRONTAL SYSTEM ASSOCIATED WITH AN LOW LOCATED OFF THE KAMCHATKA
PENINSULA COAST WILL BEGIN TO IMPACT THE WESTERN ALEUTIANS WITH
RAIN AND GALE FORCE WINDS ON SUNDAY EVENING. THIS SYSTEM WILL THEN
MOVE THROUGH THE BERING AS IT SLOWLY DISSIPATES THROUGH MONDAY.

&&

.LONG TERM FORECAST (DAYS 3 THROUGH 7)...
A WEAK LOW OVER THE WESTERN GULF WILL CONTINUE TO WEAKEN AS IT
DRIFTS EASTWARD...KEEPING MOST OF THE SHOWER ACTIVITY CONFINED TO
THE NORTH GULF COAST AND KODIAK ISLAND BEFORE DISSIPATING ON
TUESDAY. UPPER LEVEL RIDGING OVER THE EASTERN ALEUTIANS WILL BEGIN
TO AMPLIFY AND SLIDE EASTWARD OVER THE SOUTHWEST MAINLAND AND
SOUTHCENTRAL ALASKA BY TUESDAY AFTERNOON. THIS WILL BRING IN SOME
DRIER CONDITIONS TO THE INTERIOR SOUTHWEST MAINLAND THROUGH
WEDNESDAY MORNING...AND TO SOUTHCENTRAL ALASKA THROUGH WEDNESDAY
EVENING. EVEN THOUGH CURRENT GUIDANCE IS IN GOOD AGREEMENT WITH
A BLOCKING RIDGE SETTING UP OVER THE EASTERN DOMAIN BY MID
WEEK...THE MODELS CONTINUE TO STRUGGLE WITH THE TIMING AND
STRENGTH OF SMALLER SCALE DISTURBANCES AND LOW POSITIONING OVER
THE WESTERN DOMAIN THROUGH MUCH OF THE LONG TERM. GLOBAL MODELS
AND WPC GUIDANCE ARE GETTING CLOSER TO A COMMON SOLUTION REGARDING
THE TRIPLE POINT LOW DEVELOPING OVER THE NORTH PACIFIC TUESDAY
AFTERNOON...BUT CONTINUE TO QUICKLY DIVERGE FROM THAT SOLUTION BY
TUESDAY NIGHT. MODELS TYPICALLY STRUGGLE WITH THIS TYPE OF
DEVELOPMENT...WHICH HAS CREATED HIGHER UNCERTAINTY WITH REGARDS TO
THE TIMING/STRENGTH OF WINDS AND PRECIPITATION THAT CAN IMPACT THE
ALASKA PENINSULA AND SOUTHWEST MAINLAND STARTING TUESDAY NIGHT.
FURTHER WEST...A DEVELOPING LOW EAST OF THE KAMCHATKA PENINSULA
WILL BEGIN TO PHASE WITH ANOTHER LOW PRESSURE SYSTEM TO THE SOUTH
ON TUESDAY...AND TRACK OVER THE WESTERN ALEUTIANS ON WEDNESDAY.
THE FRONT ASSOCIATED WITH THIS COMPLEX SYSTEM WILL TRACK ACROSS
THE ALEUTIANS FROM WEST TO EAST...BRINGING WET AND GUSTY
CONDITIONS TO MUCH OF THE ALEUTIANS AND BERING THROUGH THURSDAY
EVENING. CONDITIONS WILL BECOME MORE SHOWERY OVER MUCH OF THE
BERING AND ALEUTIAN CHAIN THROUGH FRIDAY NIGHT...AS THE LOW
WEAKENS AND TRACKS EASTWARD.

&&

.AFC WATCHES/WARNINGS/ADVISORIES...
PUBLIC...NONE.
MARINE...NONE.
FIRE WEATHER...NONE.

&&

$$





000
FXAK68 PAFC 230135
AFDAFC

SOUTHCENTRAL AND SOUTHWEST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE ANCHORAGE AK
435 PM AKST SAT NOV 22 2014

.ANALYSIS AND UPPER LEVELS...

A STACKED AND WEAKENING 970S LOW CENTER JUST WEST OF SAND POINT
IS SLOWLY DRIFTING ESE AND WEAKENING. RAIN AND SHOWERS ASSOCIATED
WITH THIS FEATURE WERE OBSERVED OVER THE AK PENINSULA. BRISK
NORTHERLY WINDS AND SHOWERS WERE EVIDENT ON THE BACKSIDE OF THE
CENTER OVER THE CENTRAL AND EASTERN ALEUTIANS. AN UPPER LEVEL WAVE
AND WEAK SURFACE REFLECTION JUST SOUTH OF WESTERN PRINCE WILLIAM
SOUND WAS MOVING NORTH AND WEST. RADAR IMAGERY SHOWERS ENHANCED
RETURNS HEADING TOWARD THE EASTERN KENAI PENINSULA WITH RAIN AND
SHOWERS REPORTED AT STATIONS THIS AFTERNOON. TEMPS ALONG THE GULF
COAST...BRISTOL BAY...AND AK PEN/ALEUTIANS CONTINUED FAIRLY MILD.
WEAK COLD ADVECTION WITH OFFSHORE FLOW DROPPED TEMPS OVER THE
DELTA INTO THE TEENS. COLDEST TEMPS ACROSS THE FORECAST AREA WERE
STILL IN THE COPPER RIVER BASIN WITH VALUES FROM -2 TO SINGLE
DIGITS ABOVE IN LOW LYING AREAS.

&&

.MODEL DISCUSSION(SHORT TERM)...
MODELS INITIALIZED FAIRLY WELL THIS MORNING. FORECAST TRENDS ARE
IN GOOD AGREEMENT THROUGH THE SHORT TERM. THE GEM REGIONAL WAS
USED IN THE WEST DURING THE EARLY PART OF THE SHORT TERM WITH A
TRANSITION INTO A NAM/EC BLEND FOR THE REMAINDER. IN THE
EAST...THE NAM WILL BE USED EARLY ON FOLLOWED BY A TRANSITION TO A
NAM/EC BLEND.

&&

.SHORT TERM FORECAST SOUTHCENTRAL ALASKA (DAYS 1 AND 2)...
A DISSIPATING FRONT ALONG THE NORTH GULF COAST AND A SERIES OF
WEAK DISTURBANCES ROTATING THROUGH THE GULF WILL KEEP SHOWER
ACTIVITY FOCUSED MAINLY ALONG THE COAST THROUGH MONDAY. THE FIRST
OF THESE UPPER WAVES WILL HELP TO SPREAD SNOW SHOWERS OVER INLAND
PORTIONS OF THE AREA TONIGHT AS DOWNSLOPE FLOW WEAKENS...ALTHOUGH
DRY AIR AT THE SURFACE WILL KEEP THESE SHOWERS FAIRLY LIMITED IN
COVERAGE. ANOTHER WAVE WILL THEN MOVE THROUGH LATER SUNDAY AND
PROVIDE ANOTHER SHOT OF ENHANCED SHOWER ACTIVITY. SHOWERS WILL
BEGIN TO DIMINISH ACROSS THE AREA MONDAY NIGHT INTO TUESDAY AS THE
LOW CURRENTLY OVER THE ALASKA PENINSULA WEAKENS INTO AN OPEN
TROUGH AND MOVES EAST OF THE AREA.

&&

.SHORT TERM FORECAST SOUTHWEST ALASKA (DAYS 1 THROUGH 3)...
WITH THE EXCEPTION OF SOUTHERN BRISTOL BAY...MOST OF THE SOUTHWEST
MAINLAND WILL REMAIN UNDER PARTLY TO MOSTLY CLOUDY SKIES THROUGH
THE END OF THE WEEKEND. ISOLATED TO SCATTERED RAIN/SNOW SHOWERS
MAY FORM IN THE AREA ON SUNDAY AS A WEAK ELONGATED UPPER LEVEL
TROUGH DEVELOPS...HOWEVER THESE SHOULD LARGELY BE LIMITED TO
SOUTHERN BRISTOL BAY. TEMPERATURES ARE EXPECTED TO FALL INTO THE
SINGLE DIGITS OVER IN NEXT FEW NIGHTS IN THE KUSKOKWIM VALLEY AND
INLAND BRISTOL BAY AS THE LOW NEAR THE AKPENN CONTINUES TO SLOWLY
WEAKEN...AND WEAK RIDGING BEINGS TO DEVELOP. THESE TEMPERATURES
WILL THEN CONTINUE UNDER MOSTLY CLEAR SKIES UNTIL TUESDAY WHEN A
WEAK FRONT SLIDES ONSHORE FROM THE BERING.

&&

.SHORT TERM FORECAST BERING SEA/ALEUTIANS (DAYS 1 THROUGH 3)...

THE LOW CENTERED JUST SOUTH OF THE AKPENN WILL CONTINUE TO BRING
SNOW SHOWERS TO THE BERING...BECOMING RAIN SHOWERS TOWARDS THE
ALEUTIAN ISLANDS THROUGH THIS WEEKEND. THE GUSTY NORTHWESTERLY
WINDS ACCOMPANYING THESE SHOWERS WILL SLOWLY DIMINISH THIS
WEEKEND...THEN DISSIPATE ON MONDAY AS RIDING BEGINS TO TAKE OVER.
A FRONTAL SYSTEM ASSOCIATED WITH AN LOW LOCATED OFF THE KAMCHATKA
PENINSULA COAST WILL BEGIN TO IMPACT THE WESTERN ALEUTIANS WITH
RAIN AND GALE FORCE WINDS ON SUNDAY EVENING. THIS SYSTEM WILL THEN
MOVE THROUGH THE BERING AS IT SLOWLY DISSIPATES THROUGH MONDAY.

&&

.LONG TERM FORECAST (DAYS 3 THROUGH 7)...
A WEAK LOW OVER THE WESTERN GULF WILL CONTINUE TO WEAKEN AS IT
DRIFTS EASTWARD...KEEPING MOST OF THE SHOWER ACTIVITY CONFINED TO
THE NORTH GULF COAST AND KODIAK ISLAND BEFORE DISSIPATING ON
TUESDAY. UPPER LEVEL RIDGING OVER THE EASTERN ALEUTIANS WILL BEGIN
TO AMPLIFY AND SLIDE EASTWARD OVER THE SOUTHWEST MAINLAND AND
SOUTHCENTRAL ALASKA BY TUESDAY AFTERNOON. THIS WILL BRING IN SOME
DRIER CONDITIONS TO THE INTERIOR SOUTHWEST MAINLAND THROUGH
WEDNESDAY MORNING...AND TO SOUTHCENTRAL ALASKA THROUGH WEDNESDAY
EVENING. EVEN THOUGH CURRENT GUIDANCE IS IN GOOD AGREEMENT WITH
A BLOCKING RIDGE SETTING UP OVER THE EASTERN DOMAIN BY MID
WEEK...THE MODELS CONTINUE TO STRUGGLE WITH THE TIMING AND
STRENGTH OF SMALLER SCALE DISTURBANCES AND LOW POSITIONING OVER
THE WESTERN DOMAIN THROUGH MUCH OF THE LONG TERM. GLOBAL MODELS
AND WPC GUIDANCE ARE GETTING CLOSER TO A COMMON SOLUTION REGARDING
THE TRIPLE POINT LOW DEVELOPING OVER THE NORTH PACIFIC TUESDAY
AFTERNOON...BUT CONTINUE TO QUICKLY DIVERGE FROM THAT SOLUTION BY
TUESDAY NIGHT. MODELS TYPICALLY STRUGGLE WITH THIS TYPE OF
DEVELOPMENT...WHICH HAS CREATED HIGHER UNCERTAINTY WITH REGARDS TO
THE TIMING/STRENGTH OF WINDS AND PRECIPITATION THAT CAN IMPACT THE
ALASKA PENINSULA AND SOUTHWEST MAINLAND STARTING TUESDAY NIGHT.
FURTHER WEST...A DEVELOPING LOW EAST OF THE KAMCHATKA PENINSULA
WILL BEGIN TO PHASE WITH ANOTHER LOW PRESSURE SYSTEM TO THE SOUTH
ON TUESDAY...AND TRACK OVER THE WESTERN ALEUTIANS ON WEDNESDAY.
THE FRONT ASSOCIATED WITH THIS COMPLEX SYSTEM WILL TRACK ACROSS
THE ALEUTIANS FROM WEST TO EAST...BRINGING WET AND GUSTY
CONDITIONS TO MUCH OF THE ALEUTIANS AND BERING THROUGH THURSDAY
EVENING. CONDITIONS WILL BECOME MORE SHOWERY OVER MUCH OF THE
BERING AND ALEUTIAN CHAIN THROUGH FRIDAY NIGHT...AS THE LOW
WEAKENS AND TRACKS EASTWARD.

&&

.AFC WATCHES/WARNINGS/ADVISORIES...
PUBLIC...NONE.
MARINE...NONE.
FIRE WEATHER...NONE.

&&

$$




000
FXAK68 PAFC 221319
AFDAFC

SOUTHCENTRAL AND SOUTHWEST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE ANCHORAGE AK
419 AM AKST SAT NOV 22 2014

.ANALYSIS AND UPPER LEVELS...
A BROAD LOW IS CENTERED OVER THE ALASKA PENINSULA EARLY THIS
MORNING AND IS THE MAIN INFLUENCE ACROSS THE SOUTHERN MAINLAND
AND SURROUNDING WATERS. A SHORTWAVE MOVING AHEAD OF THE MAIN LOW
CENTER CAN BE SEEN ON WV/IR SATELLITE IMAGERY MOVING NORTH INTO
THE CENTRAL GULF OF ALASKA. RAIN IS DEVELOPING ALONG THIS WAVE
WITH SCATTERED SHOWERS CONTINUING ALONG THE NORTHERN GULF ALONG A
DIMINISHING BOUNDARY. A FEW SHOWERS ARE MAKING IT INLAND ALONG THE
GULF COAST AND ACROSS THE KENAI...OTHERWISE DRY CONDITIONS
CONTINUE ACROSS THE SOUTHERN MAINLAND. A COLDER AIR MASS FILTERED
IN FROM THE YUKON AND HAS SETTLED ACROSS THE CENTRAL INTERIOR AND
INTO THE COPPER RIVER BASIN. TO THE WEST ACROSS THE BERING AND
ALEUTIANS...NORTHERLY FLOW HAS SET UP ON THE BACKSIDE OF THE LOW
WITH SHOWERY CONDITIONS CONTINUING ALONG WEAKER SHORTWAVES BEHIND
THE LOW PRESSURE SYSTEM.

&&

.MODEL DISCUSSION(SHORT TERM)...
MODELS CONTINUE TO BE IN GOOD AGREEMENT WITH THE SYNOPTIC PATTERN
THROUGH THE WEEKEND WITH ONLY MINOR CHANGES NEEDED FOR THE CURRENT
FORECAST PACKAGE. THE UPPER LOW CENTERED OVER THE ALASKA
PENINSULA REMAINS NEARLY STATIONARY UNTIL SUNDAY AFTERNOON AND
THEN BEGINS TO SHIFT EAST. THE HIGHER RESOLUTION MODELS OF THE NAM
AND CANADIAN REGIONAL WERE USED FOR HANDLING THE SHORTWAVES MOVING
AROUND THE LOW CENTER. THE MAIN FOCUS FOR PRECIPITATION OVER THE
WEEKEND IS ALONG SEVERAL SHORTWAVES MOVING NORTH THROUGH THE GULF
OF ALASKA AND THE NEXT FRONT APPROACHING THE WESTERN ALEUTIANS
ON SUNDAY.

&&

.SHORT TERM FORECAST SOUTHCENTRAL ALASKA (DAYS 1 AND 2)...
THE FORECAST CHALLENGE THROUGH THE END OF THE WEEKEND WILL BE TIMING
AND PLACEMENT OF UPPER LEVEL DISTURBANCES AS THEY MAKE THE JOURNEY
AROUND THE PERIPHERY OF A NEARLY STATIONARY LOW ALONG THE ALASKA
PENINSULA. ASIDE FROM ONE STRONGER AND WELL-DEFINED DISTURBANCE
OVER THE GULF THIS MORNING...MODELS INDICATE A PLETHORA OF WEAK
WAVES EMBEDDED IN THE FLOW. BECAUSE OF THE DIFFICULTY IN TRYING
TO TIME THESE MORE THAN 6 HOURS OUT...FORECAST CONFIDENCE IS LOW
IN THE DETAILS OF WHEN AND WHERE PRECIP WILL FALL.

GENERALLY SPEAKING THE BULK OF PRECIP WITH THESE DISTURBANCES WILL
FALL ALONG THE GULF COAST/KODIAK ISLAND. HOWEVER...WEAK FLOW ACROSS
THE COASTAL MOUNTAINS COMBINED WITH WIDESPREAD MID LEVEL INSTABILITY
WILL ALLOW SOME SHOWERS TO MOVE INLAND DIRECTLY OUT AHEAD OF EACH
DISTURBANCE. PERSISTENT OFFSHORE FLOW AT THE SURFACE IS MAINTAINING
DRY AIR IN THE COOK INLET TO SUSITNA VALLEY CORRIDOR...SO ONLY THE
HEAVIER SHOWERS WILL REACH THE GROUND.

&&

.SHORT TERM FORECAST SOUTHWEST ALASKA (DAYS 1 THROUGH 3)...

AN AREA OF LOW PRESSURE CENTERED BETWEEN COLD BAY AND SAND POINT
CONTINUES TO REMAIN QUASISTATIONARY...WITH VERY LITTLE EASTWARD
PROPAGATION OBSERVED OVER THE PAST 12 TO 24 HOURS. WITH THE LOW
NOT EXPECTED TO MOVE MUCH OVER THE NEXT 36 TO 48 HOURS...RAIN WILL
CONTINUE ACROSS THE ALASKA PENINSULA AND UPSLOPE LOCATIONS ALONG
THE ALASKA RANGE. RAIN WILL BEGIN TO TAPER OFF TO SHOWERS BY
SUNDAY AFTERNOON AS THE LOW BEGINS TO PUSH TOWARD THE GULF OF
ALASKA. FOR THE KUSKOKWIM DELTA AND LOWER KUSKOKWIM VALLEY...TEMPERATURES
WILL DROP CLOSER TO NORMAL VALUES OVERNIGHT TONIGHT AND AGAIN ON
SUNDAY NIGHT. TEMPERATURES WILL ONCE AGAIN BE ON A WARMING TREND
BY THE BEGINNING OF NEXT WEEK AS WINDS SHIFT BACK TOWARD THE SOUTH
AND CLOUD COVER INCREASES OVER THE REGION.

&&

.SHORT TERM FORECAST BERING SEA/ALEUTIANS (DAYS 1 THROUGH 3)...

THE LOW OVER THE ALASKA PENINSULA WILL ALLOW RAIN TO PERSIST ACROSS
THE EASTERN ALEUTIANS DURING THE DAY TODAY BEFORE TAPERING OFF TO
SHOWERS BY EARLY SUNDAY. MUCH OF THE BERING SEA AND ALEUTIANS WILL
CONTINUE TO SEE SCATTERED RAIN (MIXED WITH SNOW FOR THE WESTERN
HALF OF THE BERING SEA) THROUGH MUCH OF THE FORECAST WITH BROAD
CYCLONIC FLOW ASSOCIATED WITH THE LOW OVER THE ALASKA PENINSULA
COUPLED WITH COLDER AIR FILTERING OUT OF RUSSIA. THIS SETS UP A
FAVORABLE ENVIRONMENT FOR COLD AIR ADVECTION SHOWERS WITH TEMPERATURES
ALOFT COOLER THAN THE PRESENT SEA SURFACE TEMPERATURES.

AN AREA OF LOW PRESSURE PUSHING OFF OF KAMCHATKA WILL DRIVE A
FRONT ACROSS THE WESTERN BERING SEA ON SUNDAY. A SECOND AREA OF
LOW PRESSURE FROM THE NORTH PACIFIC IS EXPECTED TO DEVELOP ALONG
THE FRONT AND PUSH NORTHWARD TOWARD THE ALEUTIAN ISLANDS BY LATE
MONDAY OR EARLY TUESDAY. THIS WILL BRING YET ANOTHER ROUND OF RAIN
TO THE BERING SEA AND ALEUTIAN ISLANDS WITH THE WESTERN HALF OF
THE BERING SEA EXPERIENCING GALE FORCE WINDS EARLY NEXT WEEK.

&&

.LONG TERM FORECAST (DAYS 3 THROUGH 7)...
SYNOPTICALLY SPEAKING THE PATTERN LOOKS GENERALLY THE SAME FOR THE
INTO NEXT WEEK BUT SOME SMALLER SCALE DIFFERENCE HAVE ARISEN. THE
CURRENT LOW NEAR THE ALASKA PENINSULA/WESTERN GULF WILL CONTINUE
TO WEAKEN AS IT DRIFTS EASTWARD KEEPING MOST OF THE SHOWER
ACTIVITY CONFINED TO THE NORTH GULF COAST AND KODIAK ISLAND BEFORE
DISSIPATING ON TUESDAY. INLAND...THE CHANCE FOR SHOWERS IS
GREATLY REDUCED...EXPECT MOSTLY CLOUDY CONDITIONS WITH LIGHT NORTH
WINDS FOR MOST AREAS. A ROUND OF CLEAR CONDITIONS WILL SET UP MID-
WEEK BEFORE HIGHER CLOUDS BEGIN TO STREAM IN FROM THE WEST LATE
WEEK. FURTHER OUT WEST...THE FORECAST WILL CONTINUE TO BE
DOMINATED BY A DEVELOPING KAMCHATKA LOW PRESSURE AND ATTENDANT
FRONT SWINGING ACROSS THE ALEUTIANS FROM WEST TO EAST. THE BIGGEST
DIFFERENCE TODAY IS SLOWER PROGRESSION OF THE FRONT AND
DEVELOPMENT OF A NEW COMPACT SYSTEM ALONG THE FRONT ON
TUESDAY...WHICH WILL BRING A STRONG SYSTEM INTO THE CENTRAL BERING
SEA. A COMPLEX LOW PATTERN WILL SET UP THROUGH THE WEEK WITH
DETAILS STILL UNRESOLVED. THE SOUTHWESTERN MAINLAND COULD SEE
SOME PRECIPITATION WITH THE FRONT BY WEDNESDAY. COLD ARCTIC AIR
REMAINS NOWHERE OVER ALASKA AT THIS TIME WITH NO MAJOR SYSTEMS ON
THE HORIZON.

&&


.AFC WATCHES/WARNINGS/ADVISORIES...
PUBLIC...NONE.
MARINE...HEAVY FREEZING SPRAY 181.
FIRE WEATHER...NONE.

&&

$$

SYNOPSIS AND MODEL DISCUSSION...KH
SOUTHCENTRAL ALASKA...SEB
SOUTHWEST ALASKA/BERING SEA/ALEUTIANS...CLAY
LONG TERM...MTL




000
FXAK68 PAFC 221319
AFDAFC

SOUTHCENTRAL AND SOUTHWEST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE ANCHORAGE AK
419 AM AKST SAT NOV 22 2014

.ANALYSIS AND UPPER LEVELS...
A BROAD LOW IS CENTERED OVER THE ALASKA PENINSULA EARLY THIS
MORNING AND IS THE MAIN INFLUENCE ACROSS THE SOUTHERN MAINLAND
AND SURROUNDING WATERS. A SHORTWAVE MOVING AHEAD OF THE MAIN LOW
CENTER CAN BE SEEN ON WV/IR SATELLITE IMAGERY MOVING NORTH INTO
THE CENTRAL GULF OF ALASKA. RAIN IS DEVELOPING ALONG THIS WAVE
WITH SCATTERED SHOWERS CONTINUING ALONG THE NORTHERN GULF ALONG A
DIMINISHING BOUNDARY. A FEW SHOWERS ARE MAKING IT INLAND ALONG THE
GULF COAST AND ACROSS THE KENAI...OTHERWISE DRY CONDITIONS
CONTINUE ACROSS THE SOUTHERN MAINLAND. A COLDER AIR MASS FILTERED
IN FROM THE YUKON AND HAS SETTLED ACROSS THE CENTRAL INTERIOR AND
INTO THE COPPER RIVER BASIN. TO THE WEST ACROSS THE BERING AND
ALEUTIANS...NORTHERLY FLOW HAS SET UP ON THE BACKSIDE OF THE LOW
WITH SHOWERY CONDITIONS CONTINUING ALONG WEAKER SHORTWAVES BEHIND
THE LOW PRESSURE SYSTEM.

&&

.MODEL DISCUSSION(SHORT TERM)...
MODELS CONTINUE TO BE IN GOOD AGREEMENT WITH THE SYNOPTIC PATTERN
THROUGH THE WEEKEND WITH ONLY MINOR CHANGES NEEDED FOR THE CURRENT
FORECAST PACKAGE. THE UPPER LOW CENTERED OVER THE ALASKA
PENINSULA REMAINS NEARLY STATIONARY UNTIL SUNDAY AFTERNOON AND
THEN BEGINS TO SHIFT EAST. THE HIGHER RESOLUTION MODELS OF THE NAM
AND CANADIAN REGIONAL WERE USED FOR HANDLING THE SHORTWAVES MOVING
AROUND THE LOW CENTER. THE MAIN FOCUS FOR PRECIPITATION OVER THE
WEEKEND IS ALONG SEVERAL SHORTWAVES MOVING NORTH THROUGH THE GULF
OF ALASKA AND THE NEXT FRONT APPROACHING THE WESTERN ALEUTIANS
ON SUNDAY.

&&

.SHORT TERM FORECAST SOUTHCENTRAL ALASKA (DAYS 1 AND 2)...
THE FORECAST CHALLENGE THROUGH THE END OF THE WEEKEND WILL BE TIMING
AND PLACEMENT OF UPPER LEVEL DISTURBANCES AS THEY MAKE THE JOURNEY
AROUND THE PERIPHERY OF A NEARLY STATIONARY LOW ALONG THE ALASKA
PENINSULA. ASIDE FROM ONE STRONGER AND WELL-DEFINED DISTURBANCE
OVER THE GULF THIS MORNING...MODELS INDICATE A PLETHORA OF WEAK
WAVES EMBEDDED IN THE FLOW. BECAUSE OF THE DIFFICULTY IN TRYING
TO TIME THESE MORE THAN 6 HOURS OUT...FORECAST CONFIDENCE IS LOW
IN THE DETAILS OF WHEN AND WHERE PRECIP WILL FALL.

GENERALLY SPEAKING THE BULK OF PRECIP WITH THESE DISTURBANCES WILL
FALL ALONG THE GULF COAST/KODIAK ISLAND. HOWEVER...WEAK FLOW ACROSS
THE COASTAL MOUNTAINS COMBINED WITH WIDESPREAD MID LEVEL INSTABILITY
WILL ALLOW SOME SHOWERS TO MOVE INLAND DIRECTLY OUT AHEAD OF EACH
DISTURBANCE. PERSISTENT OFFSHORE FLOW AT THE SURFACE IS MAINTAINING
DRY AIR IN THE COOK INLET TO SUSITNA VALLEY CORRIDOR...SO ONLY THE
HEAVIER SHOWERS WILL REACH THE GROUND.

&&

.SHORT TERM FORECAST SOUTHWEST ALASKA (DAYS 1 THROUGH 3)...

AN AREA OF LOW PRESSURE CENTERED BETWEEN COLD BAY AND SAND POINT
CONTINUES TO REMAIN QUASISTATIONARY...WITH VERY LITTLE EASTWARD
PROPAGATION OBSERVED OVER THE PAST 12 TO 24 HOURS. WITH THE LOW
NOT EXPECTED TO MOVE MUCH OVER THE NEXT 36 TO 48 HOURS...RAIN WILL
CONTINUE ACROSS THE ALASKA PENINSULA AND UPSLOPE LOCATIONS ALONG
THE ALASKA RANGE. RAIN WILL BEGIN TO TAPER OFF TO SHOWERS BY
SUNDAY AFTERNOON AS THE LOW BEGINS TO PUSH TOWARD THE GULF OF
ALASKA. FOR THE KUSKOKWIM DELTA AND LOWER KUSKOKWIM VALLEY...TEMPERATURES
WILL DROP CLOSER TO NORMAL VALUES OVERNIGHT TONIGHT AND AGAIN ON
SUNDAY NIGHT. TEMPERATURES WILL ONCE AGAIN BE ON A WARMING TREND
BY THE BEGINNING OF NEXT WEEK AS WINDS SHIFT BACK TOWARD THE SOUTH
AND CLOUD COVER INCREASES OVER THE REGION.

&&

.SHORT TERM FORECAST BERING SEA/ALEUTIANS (DAYS 1 THROUGH 3)...

THE LOW OVER THE ALASKA PENINSULA WILL ALLOW RAIN TO PERSIST ACROSS
THE EASTERN ALEUTIANS DURING THE DAY TODAY BEFORE TAPERING OFF TO
SHOWERS BY EARLY SUNDAY. MUCH OF THE BERING SEA AND ALEUTIANS WILL
CONTINUE TO SEE SCATTERED RAIN (MIXED WITH SNOW FOR THE WESTERN
HALF OF THE BERING SEA) THROUGH MUCH OF THE FORECAST WITH BROAD
CYCLONIC FLOW ASSOCIATED WITH THE LOW OVER THE ALASKA PENINSULA
COUPLED WITH COLDER AIR FILTERING OUT OF RUSSIA. THIS SETS UP A
FAVORABLE ENVIRONMENT FOR COLD AIR ADVECTION SHOWERS WITH TEMPERATURES
ALOFT COOLER THAN THE PRESENT SEA SURFACE TEMPERATURES.

AN AREA OF LOW PRESSURE PUSHING OFF OF KAMCHATKA WILL DRIVE A
FRONT ACROSS THE WESTERN BERING SEA ON SUNDAY. A SECOND AREA OF
LOW PRESSURE FROM THE NORTH PACIFIC IS EXPECTED TO DEVELOP ALONG
THE FRONT AND PUSH NORTHWARD TOWARD THE ALEUTIAN ISLANDS BY LATE
MONDAY OR EARLY TUESDAY. THIS WILL BRING YET ANOTHER ROUND OF RAIN
TO THE BERING SEA AND ALEUTIAN ISLANDS WITH THE WESTERN HALF OF
THE BERING SEA EXPERIENCING GALE FORCE WINDS EARLY NEXT WEEK.

&&

.LONG TERM FORECAST (DAYS 3 THROUGH 7)...
SYNOPTICALLY SPEAKING THE PATTERN LOOKS GENERALLY THE SAME FOR THE
INTO NEXT WEEK BUT SOME SMALLER SCALE DIFFERENCE HAVE ARISEN. THE
CURRENT LOW NEAR THE ALASKA PENINSULA/WESTERN GULF WILL CONTINUE
TO WEAKEN AS IT DRIFTS EASTWARD KEEPING MOST OF THE SHOWER
ACTIVITY CONFINED TO THE NORTH GULF COAST AND KODIAK ISLAND BEFORE
DISSIPATING ON TUESDAY. INLAND...THE CHANCE FOR SHOWERS IS
GREATLY REDUCED...EXPECT MOSTLY CLOUDY CONDITIONS WITH LIGHT NORTH
WINDS FOR MOST AREAS. A ROUND OF CLEAR CONDITIONS WILL SET UP MID-
WEEK BEFORE HIGHER CLOUDS BEGIN TO STREAM IN FROM THE WEST LATE
WEEK. FURTHER OUT WEST...THE FORECAST WILL CONTINUE TO BE
DOMINATED BY A DEVELOPING KAMCHATKA LOW PRESSURE AND ATTENDANT
FRONT SWINGING ACROSS THE ALEUTIANS FROM WEST TO EAST. THE BIGGEST
DIFFERENCE TODAY IS SLOWER PROGRESSION OF THE FRONT AND
DEVELOPMENT OF A NEW COMPACT SYSTEM ALONG THE FRONT ON
TUESDAY...WHICH WILL BRING A STRONG SYSTEM INTO THE CENTRAL BERING
SEA. A COMPLEX LOW PATTERN WILL SET UP THROUGH THE WEEK WITH
DETAILS STILL UNRESOLVED. THE SOUTHWESTERN MAINLAND COULD SEE
SOME PRECIPITATION WITH THE FRONT BY WEDNESDAY. COLD ARCTIC AIR
REMAINS NOWHERE OVER ALASKA AT THIS TIME WITH NO MAJOR SYSTEMS ON
THE HORIZON.

&&


.AFC WATCHES/WARNINGS/ADVISORIES...
PUBLIC...NONE.
MARINE...HEAVY FREEZING SPRAY 181.
FIRE WEATHER...NONE.

&&

$$

SYNOPSIS AND MODEL DISCUSSION...KH
SOUTHCENTRAL ALASKA...SEB
SOUTHWEST ALASKA/BERING SEA/ALEUTIANS...CLAY
LONG TERM...MTL





000
FXAK68 PAFC 220436
AFDAFC

SOUTHCENTRAL AND SOUTHWEST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE ANCHORAGE AK
736 PM AKST FRI NOV 21 2014

.ANALYSIS AND UPPER LEVELS...
A FULLY OCCLUDED LOWER 960S SURFACE LOW WITH ACCOMPANYING UPPER
CENTER IS LOCATED OVER THE CENTRAL ALASKA PENINSULA. THE
ASSOCIATED FRONTAL SYSTEM EXTENDS NW TOWARD THE PRIBILOF ISLANDS THEN
EAST TO THE NORTHERN GULF OF ALASKA. EASTERLY GALES WERE EVIDENT
ACROSS THE THE NORTHERN GULF WITH NE GALES OVER THE WESTERN GULF
AND BARREN ISLANDS. BRISK NORTHWEST WINDS WERE ALSO OBSERVED ON
THE BACKSIDE OF THE SURFACE LOW OVER THE ALEUTIANS. LOCALLY BRISK
GAP WINDS WERE ALSO EVIDENT ACROSS BRISTOL BAY AND THE DELTA.
RAIN WAS MAINLY CONFINED TO THE NORTHERN GULF AND IN THE PROXIMITY
OF THE LOW OVER THE AK PEN. TEMPERATURES CONTINUED MILD OVER
ACROSS THE GULF...SOUTHCENTRAL...SW ALASKA...WITH AFTERNOON VALUES
IN THE 30S TO MID 40S. TEMPERATURES OVER THE COPPER RIVER BASIN
THOUGH LINGERED IN THE SINGLE DIGITS TO TEENS.

&&

.MODEL DISCUSSION(SHORT TERM)...
MODELS CONTINUE IN OVERALL GOOD AGREEMENT THROUGH THE WEEKEND WITH
THE STACKED LOW CONTINUING NEAR THE ALASKA PENINSULA. THE 12Z NAM
WILL BE USED IN GENERAL IN THE EAST AND THE NAM/GEM REGIONAL IN
THE WEST.

&&

.SHORT TERM FORECAST SOUTHCENTRAL ALASKA (DAYS 1 AND 2)...
SHOWERS WILL CONTINUE THROUGH THE WEEKEND ALONG THE GULF COAST AS
A FRONT OVER THE NORTHERN GULF MOVES INLAND TONIGHT AND GRADUALLY
WEAKENS. PRECIPITATION LOOKS TO REMAIN MAINLY IN THE FORM OF RAIN
ALONG THE COAST BUT WILL CONTINUE TO MIX WITH SNOW AT TIMES FARTHER
INLAND WITH MINOR ACCUMULATIONS POSSIBLE...ESPECIALLY FOR LOCATIONS
AT HIGHER ELEVATIONS SUCH AS TURNAGAIN AND THOMPSON PASS. LIMITED
SHOWER ACTIVITY WILL ALSO BEGIN TO SPREAD INLAND ACROSS THE
MOUNTAINS TONIGHT INTO SATURDAY AS A WEAK UPPER DISTURBANCE MOVES
NORTHWARD THROUGH THE GULF AND CROSS BARRIER FLOW BEGINS TO WEAKEN
AS THE FRONT DISSIPATES.

&&

.SHORT TERM FORECAST SOUTHWEST ALASKA (DAYS 1 AND 2)...
GUSTY WINDS CONTINUE TO DIMINISH OVER MUCH THE BRISTOL BAY
AREA...AS THE FULLY OCCLUDED LOW WEAKENS AND LINGERS AROUND THE
WESTERN PORTION OF THE ALASKA PENINSULA THROUGH TOMORROW EVENING.
SCATTERED RAIN SHOWERS ALONG THE ALASKA PENINSULA ARE EXPECTED TO
PERSIST THROUGH MUCH OF THE WEEKEND...AS WEAK DISTURBANCES
CONTINUE TO ROTATE AROUND THE WEAKENING LOW. STRONG SOUTHEASTERLY
FLOW AT MOUNTAIN TOP LEVEL WILL HELP KEEP DOWNSLOPING CONDITIONS
OVER THE REMAINDER OF THE BRISTOL BAY AREA...EXCEPT FOR SOME
ISOLATED RAIN SHOWER ACTIVITY CAUSED BY UPSLOPING ALONG THE AHKLUN
MOUNTAINS TONIGHT. DRIER NORTHEASTERLY FLOW ACROSS THE KUSKOKWIM
DELTA AND LOWER KUSKOKWIM VALLEY WILL BEGIN TO USHER IN COOLER
TEMPERATURES TOMORROW...BRINGING SURFACE TEMPERATURES CLOSER TO
THEIR SEASONAL NORMALS THROUGH THE WEEKEND.

&&

.SHORT TERM FORECAST BERING SEA/ALEUTIANS (DAYS 1 AND 2)...
RAIN AND RAIN SHOWERS WILL PERSIST THROUGH THE WEEKEND FOR MUCH OF
THE BERING AND ALEUTIAN CHAIN...AS THE FULLY OCCLUDED LOW LINGERS
AROUND THE WESTERN ALASKA PENINSULA AND SLOWLY WEAKENS THROUGH
THE WEEKEND. OPERATIONAL MODELS ARE IN GOOD AGREEMENT KEEPING
CYCLONIC FLOW OVER MUCH OF THE AREA...AND BRINGING IN AN AREA OF
WEAK COLD AIR ADVECTION OVER THE WESTERN AND CENTRAL
ALEUTIANS/BERING SEA THROUGH SUNDAY MORNING. THIS HAS INCREASED
FORECAST CONFIDENCE IN INSTABILITY SHOWERS FORMING OVER WESTERN
AND CENTRAL ALEUTIANS/BERING SEA THROUGH SUNDAY MORNING. A FRONTAL
SYSTEM WILL THEN TRACK INTO THE WESTERN ALEUTIANS DURING THE DAY
SUNDAY...BRINGING MORE STRATIFORM RAINFALL AND SLIGHTLY WARMER
TEMPERATURES TO THE AREA.

&&

.LONG TERM FORECAST (DAYS 3 THROUGH 7)...
THE DIMINISHING LOW NEAR KODIAK WILL SLOWLY TRACK NORTHEAST AND
BRING MORE RAIN TO THE NORTHERN GULF COAST INTO TUESDAY.
HOWEVER...NOT MUCH OF THAT PRECIPITATION IS EXPECTED TO MAKE IT
THROUGH THE COASTAL MOUNTAINS. THE NEXT LOW WILL MAKE IT INTO THE
WESTERN BERING BY MONDAY AND THE MODELS ARE HAVING A MORE
DIFFICULT TIME WITH THIS SYSTEM. FOR THE MOST PART THEY ARE
BRINGING UP A SECONDARY LOW THAT MOVES TO THE SOUTH OF THE
ALEUTIANS SOMETIME ON TUESDAY NIGHT AND THEN ABSORBS THE WEAKENING
WEST BERING LOW. THAT IMPLIES A FURTHER SOUTH TRACK OF THE SYSTEM
AS IT PUSHES EAST THAT SHOULD STAY TO THE SOUTH OF THE ALEUTIANS.
THE OPERATIONAL EC THEN PUSHES THE LOW SOUTH INTO THE NORTH
PACIFIC LATE ON THURSDAY WHILE THE GFS...GFS ENSEMBLE AND EC
ENSEMBLE BRING THE LOW CLOSER TO KODIAK. THE TRACK TOWARD KODIAK
WAS CHOSEN WHICH WOULD BRING MORE PRECIPITATION TO THE
SOUTHCENTRAL FRIDAY.

&&

.AFC WATCHES/WARNINGS/ADVISORIES...
PUBLIC...NONE.
MARINE...NONE.
FIRE WEATHER...NONE.

&&

$$




000
FXAK68 PAFC 220436
AFDAFC

SOUTHCENTRAL AND SOUTHWEST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE ANCHORAGE AK
736 PM AKST FRI NOV 21 2014

.ANALYSIS AND UPPER LEVELS...
A FULLY OCCLUDED LOWER 960S SURFACE LOW WITH ACCOMPANYING UPPER
CENTER IS LOCATED OVER THE CENTRAL ALASKA PENINSULA. THE
ASSOCIATED FRONTAL SYSTEM EXTENDS NW TOWARD THE PRIBILOF ISLANDS THEN
EAST TO THE NORTHERN GULF OF ALASKA. EASTERLY GALES WERE EVIDENT
ACROSS THE THE NORTHERN GULF WITH NE GALES OVER THE WESTERN GULF
AND BARREN ISLANDS. BRISK NORTHWEST WINDS WERE ALSO OBSERVED ON
THE BACKSIDE OF THE SURFACE LOW OVER THE ALEUTIANS. LOCALLY BRISK
GAP WINDS WERE ALSO EVIDENT ACROSS BRISTOL BAY AND THE DELTA.
RAIN WAS MAINLY CONFINED TO THE NORTHERN GULF AND IN THE PROXIMITY
OF THE LOW OVER THE AK PEN. TEMPERATURES CONTINUED MILD OVER
ACROSS THE GULF...SOUTHCENTRAL...SW ALASKA...WITH AFTERNOON VALUES
IN THE 30S TO MID 40S. TEMPERATURES OVER THE COPPER RIVER BASIN
THOUGH LINGERED IN THE SINGLE DIGITS TO TEENS.

&&

.MODEL DISCUSSION(SHORT TERM)...
MODELS CONTINUE IN OVERALL GOOD AGREEMENT THROUGH THE WEEKEND WITH
THE STACKED LOW CONTINUING NEAR THE ALASKA PENINSULA. THE 12Z NAM
WILL BE USED IN GENERAL IN THE EAST AND THE NAM/GEM REGIONAL IN
THE WEST.

&&

.SHORT TERM FORECAST SOUTHCENTRAL ALASKA (DAYS 1 AND 2)...
SHOWERS WILL CONTINUE THROUGH THE WEEKEND ALONG THE GULF COAST AS
A FRONT OVER THE NORTHERN GULF MOVES INLAND TONIGHT AND GRADUALLY
WEAKENS. PRECIPITATION LOOKS TO REMAIN MAINLY IN THE FORM OF RAIN
ALONG THE COAST BUT WILL CONTINUE TO MIX WITH SNOW AT TIMES FARTHER
INLAND WITH MINOR ACCUMULATIONS POSSIBLE...ESPECIALLY FOR LOCATIONS
AT HIGHER ELEVATIONS SUCH AS TURNAGAIN AND THOMPSON PASS. LIMITED
SHOWER ACTIVITY WILL ALSO BEGIN TO SPREAD INLAND ACROSS THE
MOUNTAINS TONIGHT INTO SATURDAY AS A WEAK UPPER DISTURBANCE MOVES
NORTHWARD THROUGH THE GULF AND CROSS BARRIER FLOW BEGINS TO WEAKEN
AS THE FRONT DISSIPATES.

&&

.SHORT TERM FORECAST SOUTHWEST ALASKA (DAYS 1 AND 2)...
GUSTY WINDS CONTINUE TO DIMINISH OVER MUCH THE BRISTOL BAY
AREA...AS THE FULLY OCCLUDED LOW WEAKENS AND LINGERS AROUND THE
WESTERN PORTION OF THE ALASKA PENINSULA THROUGH TOMORROW EVENING.
SCATTERED RAIN SHOWERS ALONG THE ALASKA PENINSULA ARE EXPECTED TO
PERSIST THROUGH MUCH OF THE WEEKEND...AS WEAK DISTURBANCES
CONTINUE TO ROTATE AROUND THE WEAKENING LOW. STRONG SOUTHEASTERLY
FLOW AT MOUNTAIN TOP LEVEL WILL HELP KEEP DOWNSLOPING CONDITIONS
OVER THE REMAINDER OF THE BRISTOL BAY AREA...EXCEPT FOR SOME
ISOLATED RAIN SHOWER ACTIVITY CAUSED BY UPSLOPING ALONG THE AHKLUN
MOUNTAINS TONIGHT. DRIER NORTHEASTERLY FLOW ACROSS THE KUSKOKWIM
DELTA AND LOWER KUSKOKWIM VALLEY WILL BEGIN TO USHER IN COOLER
TEMPERATURES TOMORROW...BRINGING SURFACE TEMPERATURES CLOSER TO
THEIR SEASONAL NORMALS THROUGH THE WEEKEND.

&&

.SHORT TERM FORECAST BERING SEA/ALEUTIANS (DAYS 1 AND 2)...
RAIN AND RAIN SHOWERS WILL PERSIST THROUGH THE WEEKEND FOR MUCH OF
THE BERING AND ALEUTIAN CHAIN...AS THE FULLY OCCLUDED LOW LINGERS
AROUND THE WESTERN ALASKA PENINSULA AND SLOWLY WEAKENS THROUGH
THE WEEKEND. OPERATIONAL MODELS ARE IN GOOD AGREEMENT KEEPING
CYCLONIC FLOW OVER MUCH OF THE AREA...AND BRINGING IN AN AREA OF
WEAK COLD AIR ADVECTION OVER THE WESTERN AND CENTRAL
ALEUTIANS/BERING SEA THROUGH SUNDAY MORNING. THIS HAS INCREASED
FORECAST CONFIDENCE IN INSTABILITY SHOWERS FORMING OVER WESTERN
AND CENTRAL ALEUTIANS/BERING SEA THROUGH SUNDAY MORNING. A FRONTAL
SYSTEM WILL THEN TRACK INTO THE WESTERN ALEUTIANS DURING THE DAY
SUNDAY...BRINGING MORE STRATIFORM RAINFALL AND SLIGHTLY WARMER
TEMPERATURES TO THE AREA.

&&

.LONG TERM FORECAST (DAYS 3 THROUGH 7)...
THE DIMINISHING LOW NEAR KODIAK WILL SLOWLY TRACK NORTHEAST AND
BRING MORE RAIN TO THE NORTHERN GULF COAST INTO TUESDAY.
HOWEVER...NOT MUCH OF THAT PRECIPITATION IS EXPECTED TO MAKE IT
THROUGH THE COASTAL MOUNTAINS. THE NEXT LOW WILL MAKE IT INTO THE
WESTERN BERING BY MONDAY AND THE MODELS ARE HAVING A MORE
DIFFICULT TIME WITH THIS SYSTEM. FOR THE MOST PART THEY ARE
BRINGING UP A SECONDARY LOW THAT MOVES TO THE SOUTH OF THE
ALEUTIANS SOMETIME ON TUESDAY NIGHT AND THEN ABSORBS THE WEAKENING
WEST BERING LOW. THAT IMPLIES A FURTHER SOUTH TRACK OF THE SYSTEM
AS IT PUSHES EAST THAT SHOULD STAY TO THE SOUTH OF THE ALEUTIANS.
THE OPERATIONAL EC THEN PUSHES THE LOW SOUTH INTO THE NORTH
PACIFIC LATE ON THURSDAY WHILE THE GFS...GFS ENSEMBLE AND EC
ENSEMBLE BRING THE LOW CLOSER TO KODIAK. THE TRACK TOWARD KODIAK
WAS CHOSEN WHICH WOULD BRING MORE PRECIPITATION TO THE
SOUTHCENTRAL FRIDAY.

&&

.AFC WATCHES/WARNINGS/ADVISORIES...
PUBLIC...NONE.
MARINE...NONE.
FIRE WEATHER...NONE.

&&

$$





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