908
FXAK69 PAFG 091054
AFDAFG
NORTHERN ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE FAIRBANKS AK
254 AM AKDT TUE SEP 9 2025
SYNOPSIS
BROAD TROUGHING CONTINUES OVER THE WESTERN PORTION OF THE STATE
WITH A SHORTWAVE FEATURE DEVELOPING INTO A CLOSED LOW OVER THE
WESTERN NORTH SLOPE. THIS WILL RESULT IN SOME DRIER, COOLER
WEATHER ALONG THE WESTERN PORTION OF THE STATE. A MUCH MORE WET
AND ACTIVE PATTERN IS EXPECTED OVER THE BROOKS RANGE WITH A WINTRY
MIX LIKELY ALONG THE HIGH ELEVATIONS OF THE EASTERN BROOKS RANGE
AND DECENT SNOWFALL ACCUMULATIONS ALONG THE WESTERN NORTH SLOPE.
LATE SEASON ISOLATED THUNDERSTORM HAVE A CHANCE TO RETURN FOR THE
UPPER TANANA ON THURSDAY WITH SOME INSTABILITY MOVING OVER THE
ALASKA RANGE WITH FROM THE REMNANTS OF A LOW PRESSURE SYSTEM FROM
THE GULF.
KEY WEATHER MESSAGES
CENTRAL AND EASTERN INTERIOR...
- SCATTERED SHOWERS WILL PICK UP AGAIN TONIGHT THROUGH WEDNESDAY
ALONG A LINE BETWEEN BETTLES AND MCGRATH WHERE TOTAL RAINFALL
AMOUNTS RANGE FROM 0.25 TO 0.75" THROUGH THURSDAY.
- ISOLATED RAIN SHOWERS ARE FORECAST ACROSS THE EASTERN INTERIOR
WITH AROUND 0.1" ACROSS THE HIGHER ELEVATIONS THROUGH WEDNESDAY
WITH LOCALLY HIGHER AMOUNTS IN HEAVIER SHOWERS OR EMBEDDED
THUNDERSTORMS.
- MORE NUMEROUS RAIN SHOWERS AND COOLER TEMPERATURES ARE EXPECTED
ALONG AND BEHIND A FRONTAL BOUNDARY PUSHING FARTHER EAST
THURSDAY THROUGH SATURDAY.
- STEADY RAIN CHANCES ALONG THE SOUTHERN SLOPES OF THE ALASKA
RANGE LATE TUESDAY THROUGH LATE THIS WEEK. HIGHER ELEVATIONS
ALONG THE PARKS HIGHWAY MAY RECEIVE ACCUMULATING SNOW THURSDAY
NIGHT INTO FRIDAY.
WEST COAST AND WESTERN INTERIOR...
- COOL AND DRY CONDITIONS OVER THE WEST COAST WILL SPREAD INTO THE
WESTERN INTERIOR THROUGHOUT TODAY. DECREASING CLOUD COVER WITH
PATCHES OF CLEAR SKIES THROUGH WEDNESDAY NIGHT FOR PORTIONS OF
THE WEST COAST.
- NORTHERLY WINDS INCREASING TO 20-30 MPH ALONG THE WEST COAST
TUESDAY INTO WEDNESDAY
NORTH SLOPE AND BROOKS RANGE..
- LIGHT RAIN DIMINISHES ACROSS THE NORTH SLOPE THROUGH THE DAY
WITH ADDITIONAL RAIN TOTALS GENERALLY LESS THAN 0.33", BUT
LOCALLY HIGHER AMOUNTS AROUND 0.5" ARE POSSIBLE BETWEEN
DEADHORSE AND ATIGUN PASS.
- HIGHER ELEVATIONS INCLUDING ATIGUN PASS ARE FORECAST TO GET 4-7
INCHES OF SNOWFALL BETWEEN TUESDAY NIGHT AND THURSDAY NIGHT.
- ACCUMULATING WET SNOW COMBINED WITH BLUSTERY NORTHEAST WINDS
ARE INCREASINGLY LIKELY ACROSS MOST OF THE NORTH SLOPE WEDNESDAY
NIGHT INTO THURSDAY. SNOW CHANCES DIMINISH THURSDAY NIGHT INTO
FRIDAY.
- 2-5 INCHES OF SNOWFALL ARE EXPECTED ACROSS MUCH OF THE NORTH
SLOPE THROUGH THURSDAY NIGHT, EXCEPT FOR COASTAL PORTIONS OF THE
EASTERN SLOPE WHERE WARMER TEMPS MAY RESULT IN PREDOMINANTLY
RAIN.
FORECAST ANALYSIS AND DISCUSSION
THE OVERALL FORECAST PATTERN REMAINS ON TRACK. THE 980MB LOW
CONTINUES TO BE TRACKING NE ALONG THE ALEUTIANS. AT THE SAME TIME,
A SHORTWAVE MOVES DOWN FROM THE NW, INGESTING SOME OF THE ENERGY
FROM THE LOW IN GULF. THIS SHORTWAVE IS LOOKING TO BECOME A CLOSED
OFF LOW BY WEDNESDAY AFTERNOON. THESE FEATURES WILL END UP
FORMING A DEFORMATION BAND FROM THE UPPER KUSKOKWIM TO THE NE
ARCTIC COAST. A DECENT BIT OF WARM AIR ADVECTION WILL BE MOVING
ACROSS THE NE ARCTIC AS THE CLOSED LOW FORMS OVER THE WESTERN
NORTH SLOPE. THIS WILL RESULT IN A RAIN/SNOW MIX AT HIGHER
ELEVATIONS ALONG PORTIONS OF THE EASTERN BROOKS RANGE BEGINNING
LATE TUESDAY NIGHT. THERE IS SOME SLIGHT CONFIDENCE FOR SOME AREAS
OF WINTRY PRECIP, WHICH INCLUDES FREEZING RAIN, FOR AREAS SE OF
KAKTOVIK. NOTHING MORE THAN A LIGHT GLAZE WOULD OCCUR. THE
FORMATION OF THE LOW OVER THE WESTERN NORTH SLOPE WILL DRAG SOME
OF THE MOISTURE OVER THAT AREA, RESULTING IN GOOD CHANCES FOR SNOW
BEGINNING LATE WEDNESDAY NIGHT. SNOWFALL ACCUMULATIONS OF 2 TO 5
INCHES CAN BE EXPECTED FOR THE CENTRAL-WESTERN NORTH SLOPE THROUGH
THURSDAY NIGHT. THE HEAVIEST SNOWFALL WILL BE FROM POINT LAY TO
BARROW, WHERE THE COLDER AIR WILL BE MORE PROMINENT. THE BOUNDARY
BETWEEN THE SNOW AND RAIN/SNOW MIX WILL SET UP JUST SE OF THE
CENTRAL BROOKS RANGE, WHICH WILL RESULT IN CONSTANT SNOWFALL ALONG
ANAKTUVUK PASS WITH ACCUMULATIONS OF 4 TO 7 INCHES POSSIBLE.
LOOKING FARTHER SE, THE UPPER TANANA WILL BE UNDER CHINOOKING
CONDITIONS THROUGH WEDNESDAY NIGHT, BEFORE BECOMING MORE SOUTHERLY
AS THE LOW MOVING NE ALONG THE ALEUTIANS FILLS IN. THIS WILL
BECOME MORE OF A SHORTWAVE FEATURE WITH THE SOUTHERLY FLOW BY
WEDNESDAY. IT WILL CONTINUE TO LIFT NORTH THROUGH THE WEEK,
DEVELOPING A NEGATIVE TILT, AS MORE BITS OF ENERGY MOVE OVER THE
RANGE INTO THE UPPER TANANA. THIS WILL RESULT IN SOME SLIGHT
CHANCES FOR STORMS ON THURSDAY ALONG THE ALCAN BOARDER.
FIRE WEATHER
CONDITIONS STAY GENERALLY STATUS QUO FOR THE UPPER TANANA VALLEY
WITH GENERALLY SOUTHERLY CHINOOK FLOW PREVAILING THOUGH
INCREASING CLOUDS AND RAIN CHANCES SHOULD ALLOW FOR A GRADUAL
COOLING TREND LATE THIS WEEK. ANOTHER ROUND OF ISOLATED
THUNDERSTORMS ARE POSSIBLE ALONG THE ALCAN THURSDAY AND FRIDAY
AFTERNOON WITH THE REMNANTS OF A LOW MOVING OVER THE RANGE.
MODELS ARE HINTING AT THE POSSIBILITY OF SOME BRIEF CLEARING IN
THE AFTERNOON WHICH WILL AID IN THE STORM DEVELOPMENT.
HYDROLOGY...NO UPDATE
SEE PREVIOUS VERSION
FLOOD WATERS ARE RECEDING AND ADDITIONAL RAINFALL IS NOT EXPECTED TO
BE HEAVY ENOUGH TO RENEW FLOOD CONCERNS. AS A RESULT, THE REMAINING
FLOOD WATCH AND ADVISORY WERE ALLOWED TO EXPIRE AT NOON ON MONDAY.
FOR THE MOST UP TO DATE FORECASTS VISIT: WEATHER.GOV/AFG AND
WEATHER.GOV/APRFC
EXTENDED FORECAST DAYS 4-7
A BROAD, MESSY TROUGH STRETCHES ACROSS THE STATE CENTERED ON A
CLOSED 534 DECAMETER UPPER LEVEL LOW OVER THE LISBURNE PENINSULA
FRIDAY. A 542 DECAMETER LOW IN THE GULF OF ALASKA WEAKENS INTO A
LARGE SHORTWAVE FEATURE THAT MOVES NORTH INTO THE ALASKA RANGE
FRIDAY. THIS FEATURE IS EXPECTED TO BRING ADDITIONAL MOISTURE INTO
THE ALASKA RANGE THROUGH SATURDAY. COOLER ARCTIC AIR ROTATES
AROUND THE STRONGER LOW AS IT SLOWLY MOVES NORTH BRINGING COOL
TEMPERATURES TO MUCH OF THE STATE FROM THE NORTHWEST. THIS WILL
ALLOW A GRADUAL CHANGEOVER FROM RAIN TO A RAIN/SNOW MIX TO JUST
SNOW IN SOME AREAS OF THE WESTERN ALASKA RANGE INCLUDING THE PARKS
HIGHWAY FROM DENALI PARK TO CANTWELL THURSDAY NIGHT THROUGH
SATURDAY.
CONFIDENCE IS STILL LOW FOR EXACTLY HOW THIS POTENTIAL SNOW EVENT
WILL PLAY OUT FOR THE PARKS HIGHWAY WITH A VERY LARGE RANGE OF
POSSIBLE SOLUTIONS. SOLUTIONS RANGE FROM ONLY RAIN, TO A SLUSHY
RAIN/SNOW MIX, TO SEVERAL INCHES OF SNOW, TO POSSIBLE LIGHT FREEZING
PRECIPITATION. CURRENTLY THE EUROPEAN MODELS ARE THE MOST AGGRESSIVE
WITH THIS WINTRY FORECAST, BUT GIVEN THE SETUP SOME WINTRY MIX IS
QUITE POSSIBLE. WE ARE CURRENTLY LEANING TOWARDS A SLUSHY WINTRY MIX
SOLUTION FOR THIS FORECAST, BUT CONFIDENCE IS STILL QUITE LOW.
ELSEWHERE, COOL CONDITIONS EXPECTED WITH SOME LIGHT SHOWERS POSSIBLE
ACROSS THE INTERIOR WITH DRIER WEATHER EXPECTED EARLY NEXT WEEK.
MODELS ARE SHOWING A GOOD LIKELIHOOD FOR ANOTHER TRIPLE-POINT LOW
FORMING IN THE N. PACIFIC BY SOMETIME SUNDAY. THE GFS PROGRESSES
THE SYSTEM, EAST, ACROSS THE GULF. THE EC MOVES THE SYSTEM NORTH,
DIRECTLY OVER THE KODIAK ISLANDS WITH IT FILLING IN BY MID-WEEK.
THE 00Z RUN OF THE CANADIAN IS ACTING AS A SORT OF "BLEND" WITH
THE OTHER GLOBAL MODELS, PROGRESSING IT ALONG THE COAST NEAR
ANCHORAGE. EACH OF THESE SOLUTIONS WILL BRING VARIOUS WIND AND
PRECIP PATTERNS AND WILL CONTINUED TO BE MONITORED.
COASTAL HAZARD POTENTIAL DAYS 3 AND 4...NONE
AFG WATCHES/WARNINGS/ADVISORIES
AK...NONE.
PK...SMALL CRAFT ADVISORY FOR PKZ801.
SMALL CRAFT ADVISORY FOR PKZ802>804-852.
SMALL CRAFT ADVISORY FOR PKZ805.
SMALL CRAFT ADVISORY FOR PKZ806.
SMALL CRAFT ADVISORY FOR PKZ816-817-851.
SMALL CRAFT ADVISORY FOR PKZ850.
SMALL CRAFT ADVISORY FOR PKZ853.
SMALL CRAFT ADVISORY FOR PKZ854.
SMALL CRAFT ADVISORY FOR PKZ856.
TWOMBLY
EXTENDED - STOKES
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