389
FXAK68 PAFC 010054
AFDAFC
SOUTHCENTRAL AND SOUTHWEST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE ANCHORAGE AK
454 PM AKDT MON MAR 31 2025
.SHORT TERM FORECAST SOUTHCENTRAL ALASKA (DAYS 1 THROUGH 3:
TONIGHT THROUGH THURSDAY)...
A STRONG UPPER LEVEL RIDGE CURRENTLY CENTERED OVER THE NORTH
PACIFIC AND BERING SEA WILL OVERWHELMINGLY ACT AS THE MAIN
INFLUENCE ON CONDITIONS ACROSS SOUTHCENTRAL, AT LEAST UNTIL WE
LURCH SLOWLY TOWARDS A MORE NOTABLE PATTERN SHIFT NEAR THE END OF
THE WEEK. FOR THE TIME BEING, STRONG NORTH TO NORTHWESTERLY FLOW
ON THE DOWNSTREAM SIDE OF THE RIDGE CONTINUES TO STREAM DOWN INTO
THE REGION. THIS STRONG OFFSHORE WIND IS KEEPING THINGS FAIRLY
CLEAR, ASIDE FROM OCCASIONAL BANDS OF UPPER CIRRUS SPILLING OVER
THE TOP OF THE RIDGE AND ACROSS THE ALASKA RANGE. THE BRISK
NORTHWESTERLY FLOW IS SUPPORTING A LEE SURFACE TROUGH ACROSS THE
FAR NORTHERN GULF, GIVING A BOOST TO THE OFFSHORE PRESSURE
GRADIENT ALONG WITH GUSTY GAP WINDS ONGOING OUT OF RESURRECTION
BAY, PASSAGE CANAL AND THOMPSON PASS.
ONLY SUBTLE CHANGE TO THE PATTERN IS EXPECTED FOR THE NEXT COUPLE
DAYS AS THE MAIN RIDGE AXIS SLOWLY SHIFTS FROM THE BERING SEA INTO
THE GULF, ALLOWING FLOW TO TURN MORE WEST/SOUTHWESTERLY WITH TIME
THROUGH WEDNESDAY. MULTIPLE SUBTLE, WEAK SHORTWAVES WILL RIDE OVER
THE RIDGE INTO SOUTHCENTRAL IN THE MEANTIME, RESULTING IN PERIODS
OF INCREASED CLOUD COVER WITH INTERMITTENT STRETCHES OF CLEAR
SKIES AND SUNSHINE. ANY PRECIPITATION AHEAD OF THESE WAVES WILL
BE FOCUSED OVER MAINLY HIGHER ELEVATIONS ALONG THE ALASKA RANGE
AND TALKEETNAS THROUGH MIDWEEK. THE RIDGE AXIS WILL CONTINUE TO
SHIFT EVEN FARTHER EAST TOWARDS THE ALASKA PANHANDLE AS FLOW
BECOMES ONSHORE AND SOUTHEASTERLY AHEAD OF A LARGE LOW DRIFTING
ACROSS THE NORTH PACIFIC. EXPECT MUCH HIGHER CHANCES FOR
WIDESPREAD RAIN AND HIGH ELEVATION SNOW BY THE END OF THE WEEK
(PARTICULARLY ALONG THE COAST) AS THIS SYSTEM APPROACHES.
-AS
.SHORT TERM FORECAST SOUTHWEST ALASKA/BERING SEA/ALEUTIANS (DAYS
1 THROUGH 3: TODAY THROUGH WEDNESDAY)...
A STRONG RIDGE OF HIGH PRESSURE REMAINS CENTERED NEAR THE CENTRAL
ALEUTIANS, BRINGING AN EXPANSIVE AREA OF STRATUS ACROSS THE
BERING SEA AND INTO PORTIONS OF SOUTHWEST ALASKA. A FRONT
STRETCHING FROM NOME TO SHEMYA HAS ENTERED THE WESTERN ALEUTIANS.
GAP WINDS TO WEAKEN BUT WILL LINGER ALONG AND SOUTH OF THE ALASKA
PENINSULA THROUGH TONIGHT. CONDITIONS REMAIN FAVORABLE FOR DRIZZLE
FOR AREAS OF SOUTHWEST NORTH OF THE KILBUCK MOUNTAINS STILL
COVERED BY A STRATUS DECK. TEMPERATURES TODAY FOR AREAS WITH CLEAR
SKIES HAVE INCREASED SIGNIFICANTLY IN COMPARISON TO OTHER
PORTIONS OF SOUTHWEST. AREAS OF ANY LINGERING LIGHT PRECIPITATION
MAY BEGIN AS RAIN OR DRIZZLE, BUT WILL LIKELY TRANSITION TO LIGHT
SNOW OR FREEZING DRIZZLE THROUGH THE NIGHT. ACROSS MUCH OF THE
BERING SEA/ALEUTIANS AND COASTAL SOUTHWEST ALASKA, FOG IS EXPECTED
TO EXPAND AND POTENTIALLY INTENSIFY AS MOISTURE BUILDS UP IN THE
MARINE LAYER UNDER THE WARMER AIR ALOFT. KUSKOKWIM REGION WILL SEE
SOME SLIGHTLY INCREASED CHANCES FOR PRECIPITATION TONIGHT THROUGH
TUESDAY MORNING.
BY TUESDAY AFTERNOON/EVENING, THE BERING FRONT PUSHES EAST TO THE
KUSKOKWIM DELTA AND PRIBILOF ISLANDS BRINGING PRECIPITATION. THIS
MAY BEGIN AS RAIN, BUT TRANSITIONS TO SNOW BEFORE PRECIPITATION
ENDS AS MUCH COLDER AIR MOVES IN ALOFT WITH THE FRONT ON TUESDAY
NIGHT. THE FRONT WEAKENS AS IT PUSHES INTO BRISTOL BAY AND THE
LOWER KUSKOKWIM VALLEY ON WEDNESDAY, BRINGING ONLY SOME SCATTERED
SHOWERS, WHILE MORE STEADY RAIN IS SEEN ALONG THE ALEUTIAN ISLANDS
AND KUSKOKWIM DELTA.
ALSO BEGINNING WEDNESDAY, A STRONG LOW PRESSURE SYSTEM BUILDING IN
THE NORTHERN PACIFIC WILL BEGIN TO APPROACH THE CENTRAL ALEUTIANS.
WITH COLDER AIR IN PLACE COURTESY OF THE COLD FRONT THAT MOVES
THROUGH MONDAY/TUESDAY, CONDITIONS MAY BE RIPE FOR A PERIOD OF
SUSTAINED SNOWFALL ALONG THE EASTERN ALEUTIANS AND ALASKA
PENINSULA. WHILE THE LOW CENTER IS NOT EXPECTED TO ARRIVE UNTIL
LATE THIS WORK WEEK, IT IS EXPECTED TO MAINTAIN A BAND OF SHOWERS
OVER THE CENTRAL ALEUTIANS FROM WEDNESDAY THROUGH LATE THURSDAY.
STRONG NORTHERLY WINDS WILL BUILD ACROSS THE SOUTHERN BERING
CONTINUING TO INTENSIFY INTO THE WEEKEND. LOOKING AHEAD INTO
FRIDAY THIS SYSTEM WILL MAKE ITS APPROACH TO THE COASTLINE,
BRINGING A STRONG SHOT OF MOISTURE TO MUCH OF THE ALASKA
PENINSULA, SOUTHWEST ALASKA, AND THE EASTERN ALEUTIANS. CONFIDENCE
WITH REGARDS TO THE PRESENCE OF COLD AIR LINGERING IN THE AREA
PRODUCING SNOWFALL VERSUS RAINFALL IS STILL UNDER INVESTIGATION
BUT AT THIS TIME THERE IS THE POTENTIAL FOR STEADY SNOW
ACCUMULATION AT SEA LEVEL. STAY TUNED TO THE FORECAST AS REFINE
THE EXPECTED DETAILS ON THIS UPCOMING SYSTEM.
-CL
LONG TERM FORECAST (DAYS 4 THROUGH 7: FRIDAY TO MONDAY)
AN UPPER LEVEL TROUGH OVER CENTRAL BERING ELONGATES SOUTHWARD ACROSS
THE ALEUTIANS THURSDAY INTO FRIDAY. THIS IS FOLLOWED BY A STRONG
LOW PRESSURE SYSTEM THAT LIFTS FROM THE NORTH PACIFIC TOWARD THE
ALASKA PENINSULA FRIDAY AFTERNOON. WIDESPREAD GALES ARE EXPECTED
ACROSS THE ALEUTIAN CHAIN AND NORTHERN GULF COAST. THE MOST
INTENSE WINDS ARE EXPECTED TO ARRIVE FRIDAY AFTERNOON ACROSS THE
ALASKA PENINSULA. SOUTHERLY FLOW WILL BRING ABOVE AVERAGE
TEMPERATURES AND MOSTLY RAIN FOR AREAS EAST OF THE ALASKA
PENINSULA. NORTHERLY FLOW TO THE WEST WILL BRING SNOW TO UNALASKA,
WITH RECORD APRIL SNOWFALL AMOUNTS POSSIBLE (8 INCHES OR GREATER)
THROUGH SATURDAY MORNING, AND LIGHTER RATES CONTINUING THROUGH
SUNDAY AFTERNOON. SEVERAL INCHES OF RAIN ARE EXPECTED FOR KODIAK,
THE EASTERN KENAI PENINSULA, AND NORTHERN GULF COAST WHILE THE LOW
TRACKS SLOWLY EASTWARD, SOUTH OF KODIAK ISLAND AND THE WESTERN
GULF THROUGH MONDAY.
.AVIATION...
PANC...VFR CONDITIONS AND LIGHT WINDS WILL PERSIST.
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