685
FXAK68 PAFC 241341
AFDAFC
SOUTHCENTRAL AND SOUTHWEST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE ANCHORAGE AK
541 AM AKDT FRI APR 24 2026
.SHORT TERM FORECAST SOUTHCENTRAL ALASKA (DAYS 1 THROUGH
3/TODAY THROUGH SUNDAY EVENING)...
KEY POINTS:
* CONTINUED UNSEASONABLY WET AND WINDY WEATHER THROUGH LATE
TONIGHT.
* THE WETTEST WEATHER WILL BE THE EASTERN KENAI PENINSULA, PRINCE
WILLIAM SOUND, AND SUSITNA VALLEY.
* ADDITIONAL RAINFALL THROUGH SATURDAY MORNING: 1 TO 3.5" ALONG
THE GULF AND PRINCE WILLIAM SOUND COASTLINES (INCLUDING SEWARD,
WHITTIER, VALDEZ AND CORDOVA) 0.50 TO 1" OVER EASTERN INTERIOR
KENAI PENINSULA; 0.5 TO 1.5" IN THE WESTERN SUSITNA VALLEY; AND
LIGHTER AMOUNTS ELSEWHERE.
* A FLOOD WATCH REMAINS IN EFFECT FOR THE SUSITNA VALLEY FROM 9PM
THIS EVENING THROUGH SATURDAY MORNING. RAIN AND SNOWMELT
COMBINED WITH STILL FROZEN SURFACES COULD MAKE IT HARD FOR ALL
OF THE WATER TO FIND A PLACE TO PROPERLY DRAIN. AS A RESULT,
THERE COULD BE MINOR FLOODING OF LOW-LYING ROADS AND PROPERTIES.
* STRONG AND GUSTY SOUTHEASTERLY GAP WINDS WILL PERSIST THROUGH AT
LEAST THIS AFTERNOON. LOCATIONS THAT WILL SEE SOME OF THE
STRONGEST WINDS INCLUDE TURNAGAIN ARM, ANCHORAGE HILLSIDE, SOUTH
TO WEST ANCHORAGE, PALMER AND THE KNIK RIVER VALLEY, AND
GLENNALLEN AND THE COPPER RIVER.
A HIGH AMPLITUDE UPPER-LEVEL WEATHER PATTERN REMAINS FIRMLY
ENTRENCHED OVER ALASKA, WITH A TROUGH IN THE BERING SEA/NORTH
PACIFIC AND A RIDGE EXTENDING FROM THE NORTHEAST PACIFIC TO THE
TO THE ALASKA PANHANDLE AND YUKON TERRITORY. DEEP AND MOIST
SOUTHERLY FLOW IS NOTED IN WATER VAPOR WITH A MOISTURE PLUME
STREAMING NORTHWARD FROM AROUND 40N LATITUDE UP TO THE NORTHERN
GULF. A SERIES OF VIGOROUS SHORTWAVES CAN ALSO BE SEEN IN
SATELLITE IMAGERY, WITH THE STRONGEST MOVING NORTH OVER COOK INLET
THIS MORNING. AT THE SURFACE, AN AREA OF LOW PRESSURE IS MOVING
OVER AUGUSTINE ISLAND, WITH ITS WARM FRONT MOVING TOWARD PRINCE
WILLIAM SOUND AND ITS TRAILING COLD FRONT DRAPED JUST WEST OF
KODIAK ISLAND. AS THESE FEATURES MOVE NORTHWARD THIS MORNING,
STRONG SOUTHEASTERLY GAP WINDS AND STEADY RAIN WILL CONTINUE
ACROSS SOUTHCENTRAL ALASKA.
THE HEAVIEST PRECIPITATION WILL BE ACROSS THE SOUTHEASTERN KENAI
PENINSULA AND NORTHERN TO WESTERN SUSITNA VALLEY THROUGH LATE
FRIDAY MORNING. SOUTHEASTERLY WINDS HAVE INCREASED OVERNIGHT AND
WILL CONTINUE TO RAMP UP THROUGH LATE MORNING BEFORE SLOWLY
DIMINISHING IN INTENSITY AS THE SURFACE LOW MOVES NORTH OVER THE
WESTERN ALASKA RANGE AND QUICKLY WEAKENS. THE STRONGEST WINDS
WILL OCCUR ALONG TURNAGAIN ARM AND AFFECTING THE ANCHORAGE
HILLSIDE, WITH A FEW GUSTS OF 35 TO 45 MPH FOR WEST ANCHORAGE;
PALMER; AND GLENNALLEN; AND GUSTS OF 60 MPH OR HIGHER LIKELY FOR
UPPER POTTER MARCH AND THE UPPER HILLSIDE OF ANCHORAGE. WITH THE
GROUND STILL LARGELY FROZEN AND TREES YET TO LEAF OUT, DO NOT
EXPECT ANY SIGNIFICANT IMPACTS DUE TO THESE WINDS.
ANOTHER SHORT-WAVE WILL CROSS NEARLY THE SAME AREA LATER THIS
AFTERNOON AND EVENING. MODEL GUIDANCE CONTINUES TO ADVERTISE A
WEAKER, LESS AMPLIFIED SHORT-WAVE. AS A RESULT, GAP WINDS AND
PRECIPITATION RATES WITH THIS SHORT-WAVE LOOK LESS IMPRESSIVE; THE
LATEST FORECAST PACKAGE CONTINUES TO REFLECT THIS.
THE UPPER LEVEL FLOW WILL SHIFT BEHIND THIS SHORT-WAVE ON SATURDAY
AS A NEW STORM SYSTEM MOVES INTO THE BERING SEA, BRINGING AN END
(TEMPORARILY) TO THE DEEP SOUTHERLY FLOW AND MOISTURE TRANSPORT.
ONE FINAL SHORT-WAVE WILL CROSS THROUGH SOUTHCENTRAL DURING THE
DAY SATURDAY, BUT PRECIPITATION WITH IT WILL BE QUITE LIGHT. A
SHORT-WAVE RIDGE WILL THEN BRIEFLY MOVE THROUGH SATURDAY NIGHT
INTO SUNDAY MORNING, WITH THE FRONTAL SYSTEM FROM THE BERING STORM
FOLLOWING CLOSELY BEHIND. THE UPPER LEVEL FLOW ON SUNDAY WILL
LOOK VERY SIMILAR TO WHAT IS IN PLACE TODAY. THUS, UNSEASONABLY
WET AND WINDY WEATHER WILL RETURN LATE IN THE WEEKEND AND INTO
THE NEW WORK WEEK.
-SEB/TM
.SHORT TERM FORECAST SOUTHWEST ALASKA/BERING SEA/ALEUTIANS (DAYS
1 THROUGH 3: TODAY THROUGH SUNDAY)...
KEY MESSAGES:
- A LOW OVER THE NORTHERN BERING SEA WILL STEADILY WEAKEN THROUGH
TONIGHT.
- AN UNSEASONABLY STRONG LOW WILL RAPIDLY DEEPEN AS IT APPROACHES
THE CENTRAL PORTIONS OF THE ALEUTIANS ON SATURDAY.
- HIGH WIND WATCHES ARE NOW IN EFFECT FOR ADAK, ATKA, NIKOLSKI,
AND UNALASKA FROM SATURDAY AFTERNOON THROUGH SUNDAY AFTERNOON AS
GUSTS AS HIGH AS 70-80 MPH ARE POSSIBLE. WIDESPREAD GALE TO
STORM FORCE WINDS, WITH HURRICANE FORCE GUSTS, COULD IMPACT
MUCH OF THE MARINE OUTLOOK AREA THIS WEEKEND.
DISCUSSION:
THROUGH TONIGHT, LITTLE CHANGE IN THE GENERAL PATTERN IS EXPECTED
AS THE LOW MOVING OVER THE NORTHERN BERING SEA STEADILY WEAKENS
AND AS MULTIPLE SHORTWAVE TROUGHS CONTINUE TO MOVE NORTHEAST ALONG
THE AKPEN AND OVER SOUTHWEST. MULTIPLE ROUNDS OF MOSTLY RAIN WILL
CONTINUE TO AFFECT MUCH OF THE AKPEN, BRISTOL BAY AND KUSKOKWIM
DELTA AS THESE UPPER WAVES MOVE ACROSS. GENERALLY CALM CONDITIONS
WILL CONTINUE ACROSS THE PRIBILOFS AND ALEUTIANS, BUT THIS WILL
CHANGE RATHER ABRUPTLY OVER THE UPCOMING WEEKEND.
BY EARLY TOMORROW MORNING, A NORTH PACIFIC LOW WILL PHASE
STRONGLY WITH A POTENT TROUGH APPROACHING FROM THE WEST AND
RAPIDLY DEEPEN INTO A 950-960 MB HURRICANE FORCE LOW AS IT
APPROACHES ADAK AND ATKA BY SATURDAY AFTERNOON. MODEL AGREEMENT
FOR THIS SYSTEM CONTINUES TO IMPROVE, AND IT NOW LOOKS LIKELY THAT
THE LOW CENTER WILL CROSS OVER INTO THE SOUTHERN BERING SEA NEAR
OR JUST WEST OF ADAK BY SATURDAY EVENING. A STING JET OF INTENSE
WINDS WILL DEVELOP TO THE SOUTH OF THE LOW CENTER, AND THIS
CORRIDOR OF STRONG WINDS WILL PROGRESS NORTH INTO THE
CENTRAL/EASTERN PARTS OF THE ALEUTIAN CHAIN BY EARLY SUNDAY
MORNING. EVEN THOUGH THE LOW WILL REACH PEAK INTENSITY PRIOR TO
MOVING INTO THE BERING SEA, THIS CORRIDOR OF WINDS WILL STILL BE
QUITE INTENSE. STORM FORCE SUSTAINED WINDS WITH HURRICANE FORCE
GUSTS WILL OVERSPREAD MUCH OF THE MARINE WATERS SURROUNDING THE
EASTERN HALF OF THE ALEUTIANS, WITH POTENTIAL FOR WIND GUSTS OF 60
TO 70 MPH OR STRONGER TO IMPACT ADAK, ATKA, NIKOLSKI AND UNALASKA
AS THE LOW SHIFTS NORTH LATE SATURDAY NIGHT INTO SUNDAY. HOW
HIGH GUSTS WILL BE IN THESE LOCATIONS WILL ULTIMATELY DEPEND ON
THE TRACK OF THE LOW. MODELS ARE GENERALLY SHOWING A WESTWARD
SHIFT IN THE TRACK, WHICH MAY MEAN A DECREASING THREAT OF HIGH
WINDS FOR UNALASKA. STILL, WE'LL BE CLOSELY MONITORING HIGH WIND
POTENTIAL AS MODELS TEND TO STRUGGLE WITH THE TRACK OF RAPIDLY
INTENSIFYING LOWS. OTHERWISE, SEAS AS HIGH AS 40 FT WILL MOVE IN
TANDEM WITH THE CORRIDOR OF STRONGEST WINDS SOUTH OF THE ALEUTIANS
BETWEEN ADAK AND NIKOLSKI SATURDAY NIGHT INTO SUNDAY MORNING.
FARTHER NORTH, THE LOW'S LEADING FRONT WILL PUSH ACROSS THE
PRIBILOFS ON SATURDAY NIGHT, SPREADING PRECIPITATION INITIALLY IN
THE FORM OF SNOW ACROSS THE ISLANDS ALONG WITH SOUTHEAST WINDS
GUSTING TO AROUND 60 MPH. TEMPERATURES WILL LIKELY BE HOVERING AT
OR JUST ABOVE FREEZING BY THIS POINT, SO THIS WILL LIMIT POTENTIAL
FOR BLOWING SNOW. SNOW WILL TRANSITION TO RAIN AS TEMPERATURES
CONTINUE TO WARM ON SUNDAY MORNING, WHILE GUSTY WINDS TO THE EAST
OF THE LOW CENTER PERSIST. THE FRONT WILL REACH THE SOUTHWEST
COAST SUNDAY MORNING, WITH A SIMILAR PROGRESSION FROM WET SNOW TO
RAIN EXPECTED THROUGH THE DAY ON SUNDAY AS GUSTY SOUTHEAST WINDS
ALSO SPREAD ACROSS SOUTHWEST ALONG AND AHEAD OF THE INCOMING
FRONT. STAY TUNED FOR MORE DETAILS AS WE CONTINUE TO MONITOR THIS
UNSEASONABLY STRONG STORM SYSTEM THROUGH THIS WEEKEND.
-AS/KC
.LONG TERM FORECAST (DAYS 4 THROUGH 7: MONDAY THROUGH
THURSDAY)...
UNSETTLED WEATHER IS EXPECTED TO PERSIST ACROSS MUCH OF ALASKA
INTO EARLY NEXT WEEK AS A NORTH PACIFIC LOW MOVES INTO THE
SOUTHERN BERING. THE LOW WILL THEN TRACK NORTHWARD, PASSING
NORTHWEST OF THE PRIBILOF ISLANDS BY MONDAY WHILE GRADUALLY
WEAKENING AND OCCLUDING. STORM FORCE WINDS ARE POSSIBLE ACROSS
PORTIONS OF THE CENTRAL ALEUTIANS SUNDAY INTO MONDAY, WITH
WIDESPREAD GALE-FORCE WINDS OTHERWISE EXPECTED ACROSS THE
ALEUTIANS, MUCH OF THE BERING AND BRISTOL BAY THROUGH TUESDAY.
COASTAL IMPACTS REMAIN LIMITED AT THIS TIME DUE TO THE PRESENCE OF
SHOREFAST ICE AND AN EXTENSIVE ICE PACK OVER THE EASTERN BERING.
A FRONTAL SYSTEM ASSOCIATED WITH THIS LOW WILL MOVE INTO THE
ALASKA PENINSULA AND SOUTHWEST ALASKA SUNDAY MORNING, REACHING THE
WESTERN GULF AND KODIAK ISLAND BY SUNDAY AFTERNOON AND THEN
PROGRESSING INTO SOUTHCENTRAL ALASKA SUNDAY NIGHT. THIS SYSTEM
WILL BRING A STEADY STREAM OF MOISTURE INTO SOUTHERN ALASKA,
RESULTING IN WIDESPREAD PRECIPITATION AS THE FRONT ADVANCES. THE
HEAVIEST PRECIPITATION IS EXPECTED ACROSS KODIAK ISLAND, ALONG THE
NORTHERN GULF COAST, AND ACROSS HIGHER ELEVATIONS OF THE ALASKA
RANGE DUE TO UPSLOPE ENHANCEMENT FROM SOUTHEASTERLY FLOW. IN
CONTRAST, DOWNSLOPING EFFECTS ARE LIKELY TO LIMIT PRECIPITATION
ACROSS PORTIONS OF THE WESTERN CHUGACH AND KENAI MOUNTAINS, AS
WELL AS ALONG THE BERING SIDE OF THE ALASKA PENINSULA.
AS THE PRIMARY LOW WEAKENS AND OCCLUDES OVER THE NORTHERN BERING,
ADDITIONAL SHORTWAVE DISTURBANCES ARE EXPECTED TO ROTATE AROUND
THE PARENT LOW AND MOVE NORTHWARD INTO ALASKA. MODEL GUIDANCE IS
IN GENERAL AGREEMENT ON A SHORTWAVE MOVING INTO SOUTHCENTRAL
ALASKA MONDAY NIGHT INTO TUESDAY, WHICH WILL SUPPORT ANOTHER
PERIOD OF ENHANCED PRECIPITATION, PARTICULARLY ALONG THE NORTHERN
GULF COAST AND KODIAK ISLAND WHERE SOUTHEASTERLY FLOW PERSISTS.
BEYOND TUESDAY, MODEL SOLUTIONS BEGIN TO DIVERGE WITH RESPECT TO
THE TIMING AND PLACEMENT OF ADDITIONAL SHORTWAVES. SOME GUIDANCE
BRINGS ADDITIONAL ENERGY INTO SOUTHWEST ALASKA TUESDAY INTO
WEDNESDAY, WHILE OTHER SOLUTIONS DELAY IMPACTS INTO SOUTHCENTRAL
ALASKA UNTIL MIDWEEK. CONFIDENCE IN THE DETAILS DECREASES DURING
THIS PERIOD; HOWEVER, THE OVERALL PATTERN CONTINUES TO SUPPORT A
PERSISTENT FEED OF MOISTURE INTO SOUTHERN ALASKA, ESPECIALLY
ACROSS SOUTHCENTRAL.
LM
AVIATION
PANC... SOUTHEASTERLY TURNAGAIN ARM WINDS WILL CONTINUE THROUGH
THE DAY, BRINGING INTERMITTENT GUSTS OF 20 TO 30 KTS. TURNAGAIN
ARM WINDS WILL GRADUALLY DECREASE IN THE AFTERNOON. LLWS MAY BE
ENCOUNTERED BETWEEN FIRE ISLAND AND THE TERMINAL FOR AIRCRAFT
APPROACHING FROM THE WEST. VFR CONDITIONS ARE EXPECTED TO PERSIST,
THOUGH ANY PASSING SHOWERS MAY DROP CEILINGS BELOW 5,000 FT AGL.
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