697
FXAK68 PAFC 130003
AFDAFC
SOUTHCENTRAL AND SOUTHWEST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE ANCHORAGE AK
403 PM AKDT FRI SEP 12 2025
.SHORT TERM FORECAST SOUTHCENTRAL ALASKA
(DAYS 1 THROUGH 3: TODAY THROUGH MONDAY EVENING)...
THE LOW IN THE GULF NEAR THE KENAI PENINSULA CONTINUES TO SLOWLY
WEAKEN THROUGH TONIGHT AS IT FINALLY DISSIPATES SATURDAY.
SCATTERED SHOWERS WILL CONTINUE ACROSS THE KENAI PENINSULA,
ANCHORAGE, THE MAT-SU VALLEYS, AND PRINCE WILLIAM SOUND THROUGH
SATURDAY MORNING. LINGERING INSTABILITY ACROSS THE NORTHEASTERN
COPPER RIVER BASIN COULD KICK OFF AN ISOLATED THUNDERSTORM OR TWO
THE REST OF THIS AFTERNOON AND AGAIN ON SATURDAY AFTERNOON.
HOWEVER, CONFIDENCE IS LOWER FOR THUNDERSTORM FORMATION. SNOW
LEVELS WILL BE LOWEST IN THE NORTHERN SUSITNA VALLEY TOWARDS THE
NORTHERN END OF BROAD PASS. SOME SNOW AND OR RAIN-SNOW MIX LOOKS
TO FALL TONIGHT INTO EARLY SATURDAY MORNING UP THERE. ACCUMULATION
IS NOT EXPECTED ON THE ROADWAY HOWEVER; MORE OF A LITTLE TASTE OF
WINTER AND A REMINDER THAT WINTER IS NOT TOO FAR AWAY. FORCING
FOR ASCENT BECOMES WEAKER FOR SATURDAY WITH RAIN TAPERING OFF FOR
MOST OF THE AREA AND BECOMING MORE CONFINED TO PRINCE WILLIAM
SOUND AND THE EASTERN KENAI PENINSULA.
THE NEXT BIG WEATHER-MAKER TRACKS TO THE SOUTHERN GULF BY SUNDAY
MORNING AS A STRONG NORTH PACIFIC LOW SENDS ITS FRONT NORTHWARD.
TRENDS TODAY HAVE CONTINUED TOWARDS A SLIGHTLY MORE WESTWARD
SOLUTION WHICH WOULD FAVOR WETTER AND WINDIER CONDITIONS ACROSS
KODIAK ISLAND SUNDAY EVENING AND COASTAL SOUTHCENTRAL FOR MONDAY.
THE LOW ITSELF MOVES INTO THE SOUTHERN GULF MONDAY MORNING AS THE
FRONT MAKES IT TO THE NORTHERN GULF COAST BY THEN. AS THE FRONT
MAKES IT TO THE NORTHERN GULF COAST, WINDS WILL BE ENHANCED WITH A
CORRIDOR OF STORM-FORCE WINDS SOUTH AND WEST OF KAYAK ISLAND
MONDAY MORNING. NORTHEASTERLY GALES WILL ALSO BE LIKELY THROUGH
SOUTHERN COOK INLET, SHELIKOF STRAIT, AND ALONG THE COASTAL WATERS
OF THE EASTERN KENAI PENINSULA.
EXPECT MODERATE TO HEAVY RAIN TO ACCOMPANY THE FRONT AS IT LIFTS
TO THE COAST SUNDAY EVENING THROUGH MONDAY. ANCHORAGE AND MOST OF
THE WESTERN KENAI PENINSULA WILL SEE LIGHT RAIN AT TIMES MONDAY
AFTERNOON AND EVENING WITH STRONG DOWNSLOPING EASTERLY FLOW
PRESENT AT THE 850 MB LEVEL. HOWEVER, FROM NINILCHIK TO HOMER,
STEADIER LIGHT RAIN IS MORE LIKELY WITH BETTER MOISTURE AND LIFT.
MOST RAIN SUNDAY EVENING THROUGH MONDAY LOOKS TO FALL ALONG THE
NORTHERN GULF COAST, PRINCE WILLIAM SOUND, AND KODIAK ISLAND.
BETWEEN SUNDAY AFTERNOON AND MONDAY EVENING, PORTIONS OF KODIAK
ISLAND, INCLUDING KODIAK CITY, HAVE THE POTENTIAL TO 2 TO 2.5
INCHES OF RAIN IN AROUND A 24-HOUR PERIOD. STAY TUNED TO THE
FORECAST AS FURTHER FINE-TUNING AND UPDATES ARE EXPECTED TO BE
MADE WITH THIS WET AND WINDY SYSTEM FOR THE END OF THE WEEKEND AND
INTO THE NEW WORK WEEK.
.SHORT TERM FORECAST SOUTHWEST ALASKA/BERING SEA/ALEUTIANS (DAYS
1 THROUGH 3: TONIGHT THROUGH MONDAY)...
A BROAD LONGWAVE TROUGH EXTENDS ACROSS THE REGION WITH SEVERAL
WEAK SURFACE LOWS DRIFTING SLOWLY SOUTHEASTWARD THROUGH WEAK FLOW
IN THE BERING SEA THIS AFTERNOON. AN AREA OF LIGHT RAIN SHOWERS IS
ASSOCIATED WITH TWO OF THE MORE PROMINENT FEATURES. THE FIRST IS A
BROAD LOW LOCATED IN THE CENTRAL/WESTERN BERING SEA, PUSHING A
DISORGANIZED BAND OF LIGHT SHOWERS THROUGH THE CENTRAL
BERING/ALEUTIANS, WHILE A SECOND, MORE COMPACT LOW IN THE NORTHERN
BERING SEA IS PRODUCING SHOWERS IN THE VICINITY OF NUNIVAK ISLAND
AND OFFSHORE OF THE SOUTHWEST ALASKA COASTLINE. THESE FEATURES
DRIFT SLOWLY SOUTHEASTWARD IN THE WEAK FLOW AND DISSIPATE BY
SATURDAY NIGHT. ONLY A WEAK TROUGH AND ISOLATED SHOWERS MARK THE
REMNANTS OF THE FEATURE AS A BUILDING RIDGE IN THE WESTERN
ALEUTIANS PUSHES IT ACROSS THE EASTERN ALEUTIANS INTO THE NORTH
PACIFIC. FOR SOUTHWEST ALASKA, SOME SLIGHT INSTABILITY WITH COLD
AIR ALOFT HAS ALLOWED SHALLOW CUMULUS TO FORM TODAY AS THE NEAR
SURFACE LAYER WARMED UP WITH DAYTIME HEATING. TONIGHT, CLEAR SKIES
RETURN AS LOWER LEVELS STABILIZE AND TEMPERATURES DROP BACK TO
NEAR FREEZING FOR MANY LOCATIONS IN SOUTHWEST ALASKA. INCREASINGLY
CLEAR SKIES ARE FORECAST FOR THE KUSKOKWIM DELTA REGION, WHICH
REMAINED CLOUD-COVERED LAST NIGHT, WHICH PREVIOUSLY KEPT THE AREA
FROM DROPPING BELOW THE UPPER 30S. FOR THE NEXT SEVERAL NIGHTS,
FORECAST LOWS ARE NEAR FREEZING. IN BRISTOL BAY, HOWEVER, HIGH
LEVEL CLOUDS MOVING IN FROM THE GULF OF ALASKA WILL INCREASINGLY
BE ABLE TO LIMIT RADIATIONAL COOLING OVERNIGHT, SO FORECAST LOWS
TREND UP TOWARD 40 DEGREES BY SUNDAY NIGHT.
THESE CLOUDS WILL BE BROUGHT ALONG BY AN INTENSIFYING LOW TRACKING
INTO THE SOUTHERN GULF OF ALASKA FOR SUNDAY. THERE IS STILL SOME
UNCERTAINTY ON HOW FAR WEST THIS LOW'S FRONT SETS UP. THERE IS
SOME POTENTIAL THAT THE MAIN CORRIDOR OF GALE FORCE WINDS ALONG
THE FRONT REMAIN LARGELY EAST OF KODIAK, KEEPING WATERS TO THE
SOUTHWEST BELOW GALE FORCE. HOWEVER, THERE IS ALSO SUPPORT FOR THE
FRONT TO PUSH FURTHER WEST, BRINGING GALES SOLIDLY SOUTH OF THE
ALASKA PENINSULA. THE EASTERN SOLUTION WOULD ADDITIONALLY LIMIT
PRECIPITATION ALONG THE NORTHERN ALASKA PENINSULA, WHILE THE
WESTERN SOLUTION YIELDS MORE RAINFALL. SIMILAR UNCERTAINTY AFFECTS
A LOW IN THE NORTH PACIFIC THAT PUSHES A FRONT INTO/NEAR THE
WESTERN ALEUTIANS THIS WEEKEND. SOME MODEL SOLUTIONS PUSH THE
FRONT INTO THE WESTERN BERING SEA, WHILE OTHERS KEEP IT SOUTH OF
THE ISLAND CHAIN. REGARDLESS OF SOLUTION, HOWEVER, LIGHT TO
MODERATE RAINFALL LOOKS TO MOVE INTO THE WESTERN ALEUTIANS BY
MONDAY.
QUESADA
LONG TERM FORECAST (TUESDAY THROUGH FRIDAY)
ONLY MINOR CHANGES FROM PREVIOUS DISCUSSION... THE ACTIVE PATTERN
CONTINUES IN THE LONG TERM WITH THE MAIN STORY BEING A PAIR OF
LOWS BRINGING WIND AND RAIN FROM THE ALEUTIANS TO MUCH OF THE
MAINLAND. MODELS ARE IN FAIRLY GOOD AGREEMENT WITH THE MAIN
FEATURE TO BEGIN THE PERIOD AS A LARGE 980-990 MB SURFACE LOW
CONTINUES TO LIFT NORTH INTO THE GULF EARLY IN THE WEEK. THIS
SYSTEM LOOKS LIKELY TO PEAK IN INTENSITY TUESDAY MORNING AS IT
ENTERS THE SOUTHWESTERN GULF. HEAVY RAIN IS EXPECTED ALONG THE
EASTERN KENAI PENINSULA AND NORTHERN GULF COAST INTO TUESDAY AS
THE FRONTAL SYSTEM REACHES THE COAST. GUSTY NORTHERLY WINDS ACROSS
THE ALASKA PENINSULA ENHANCED BY COLD AIR ADVECTION ON THE
BACKSIDE OF THE LOW AS WELL AS THE POTENTIAL DEVELOPMENT OF A
GALE-FORCE BARRIER JET OUTSIDE OF PRINCE WILLIAM SOUND AHEAD OF
THE FRONT REMAIN POSSIBLE FROM THE BEGINNING OF THE PERIOD THROUGH
TUESDAY AFTERNOON.
FURTHER WEST, A SERIES OF SHORTWAVES EMERGING FROM THE KAMCHATKA
REGION AND NORTH PACIFIC LOOK TO MERGE AS THEY ENTER THE WESTERN
BERING, SHIFTING THE AXIS OF THE LONGWAVE TROUGH TO A MORE
POSITIVE TILT OVER THE BERING. THIS BECOMES THE DOMINANT FEATURE
IN THE LATTER HALF OF THE LONG TERM AS THE DECAYING SYSTEM IN THE
GULF GETS ABSORBED, FORMING A LARGE UPPER LEVEL LOW LIFTING FROM
THE NORTH PACIFIC TOWARDS BRISTOL BAY. THIS SYSTEM REACHES THE
WESTERN ALEUTIANS BY EARLY TUESDAY AND TRACKS ALONG AND JUST TO
THE SOUTH OF THE ALEUTIAN CHAIN AND ALASKA PENINSULA, SPREADING
RAINFALL AND ELEVATED WINDS WEST TO EAST ACROSS THE ALEUTIANS AND
AKPEN FROM TUESDAY THROUGH WEDNESDAY. MODEL SPREAD AND UNCERTAINTY
IN THE EASTWARD EXTENT OF THE TRACK REMAINS HIGH AT THIS TIME,
BUT EXPECT RAIN TO SPREAD INTO SOUTHWEST ALASKA AS THE LOW LIFTS
TOWARDS BRISTOL BAY AS THE FRONT SHIFTS EAST AND BRINGS ANOTHER
ROUND OF RAIN TO THE GULF LATE NEXT WEEK.
AVIATION
PANC...LIGHT AND VARIABLE WINDS ARE EXPECTED TO PERSIST ALONG
WITH NEARLY CONTINUOUS RAIN AS A SURFACE LOW LINGERS SOUTH OF THE
KENAI PENINSULA. CEILINGS AND VISIBILITY WILL LIKELY REMAIN
BETWEEN MVFR AND IFR THROUGH MUCH OF THE FORECAST PERIOD,
ALTHOUGH A PERIOD OF VFR CEILINGS IS POSSIBLE THIS AFTERNOON
THROUGH EARLY EVENING. CONDITIONS WILL LIKELY BEGIN TO IMPROVE BY
NOON SATURDAY AS THE LOW FINALLY DISSIPATES.
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