639
FXAK68 PAFC 191312
AFDAFC
SOUTHCENTRAL AND SOUTHWEST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE ANCHORAGE AK
512 AM AKDT THU MAR 19 2026
.SHORT TERM FORECAST SOUTHCENTRAL ALASKA
(DAYS 1 THROUGH 3)...
A STRONG,COMPACT LOW NEAR HINCHINBROOK ISLAND WILL SWING
NORTHWEST INTO THE SOUND THIS MORNING AND QUICKLY DISSIPATE.
MEANWHILE, A DIGGING, POSITIVELY TILTED TROUGH OVER THE NORTHEAST
GULF WILL HELP GENERATE A NEW LEE-SIDE LOW NEAR SEWARD, WHERE IT
WILL REMAIN THROUGH EARLY FRIDAY MORNING. THIS WILL BRING LIGHT TO
MODERATE SNOW SHOWERS TO COMMUNITIES AROUND THE SOUND, WITH LIGHT
SNOW FOR ANCHORAGE, THE MAT VALLEY AND WESTERN KENAI. AS THE
UPPER LEVEL TROUGH LIFTS NORTH THROUGH THE DAY, MODERATE SNOW
SHOWERS ARE LIKELY TO MOVE OVER GIRDWOOD, WHITTIER, PORTAGE AND
TURNAGAIN PASS, WHERE WINTER WEATHER ADVISORIES ARE IN PLACE.
SHOWERS ARE LIKELY TO TRAIN, WHICH MAY LEAD TO LOCALIZED AREAS OF
HIGHER AND LOWER SNOW TOTALS WITHIN THE ADVISORY AREA AS HIT OR
MISS SHOWERS MOVE OVER LOCALIZED AREAS. THE MAIN UNCERTAINTY
REMAINS THE LOCATION OF THE SURFACE LOW NEAR SEWARD, AS SLIGHT
DEVIATIONS WILL DETERMINE WHERE THE SHOWERS SET UP. THIS FORECAST
REPRESENTS HIGHER END SNOW TOTALS AND ASSUMES THE STORM IS
EFFICIENTLY USING THE INSTABILITY ASSOCIATED WITH COLD AIRMASS
WRAPPING INTO THE AREA.
BY FRIDAY THE FORECAST BEGINS TO GET VERY NOISY WITH A MULTITUDE
OF SURFACE LOWS REVOLVING AROUND THE UPPER LEVEL TROUGH IN THE
SOUTHERN GULF. ANY REMAINING PRECIPITATION RIGHT NOW LOOKS TO BE
CONFINED TO THE EASTERN KENAI PENINSULA COAST. STRONG WINDS ARE
ALSO EXPECTED TO REDEVELOP OVER THOMPSON PASS AND POSSIBLY VALDEZ,
WITH A STRONG MAT WIND POSSIBLE BY SATURDAY DEPENDING ON THE TRACK
OF THE SURFACE AND UPPER LEVEL FEATURES. OTHERWISE, THE WEEKEND
LOOKS TO BE MUCH OF THE SAME, BELOW NORMAL TEMPERATURES, SOME
SUNSHINE, AND WINDS THROUGH MOST OF THE MOUNTAIN GAPS AND PASSES.
-CJ
.SHORT TERM FORECAST SOUTHWEST ALASKA/BERING SEA/ALEUTIANS (DAYS
1 THROUGH 3)...
THE PATTERN REMAINS THE SAME AS IT HAS BEEN, RIDGING IN THE
WESTERN BERING AND TROUGHING OVER SOUTHWEST ALASKA. AN UPPER LEVEL
ARCTIC LOW IS DROPPING THROUGH THE SOUTHWEST MAINLAND, WHICH WILL
ALLOW FOR AN INCREASE IN WIND SPEEDS IN THE EAST BERING, AS WELL
AS SNOW SHOWERS DOWNSTREAM OF AREAS OF OPEN WATER. NORTHERLY GAP
WINDS UP TO GALE FORCE IN STRENGTH WILL CONTINUE TO BLOW THROUGH
GAPS AND PASSES IN THE EASTERN ALEUTIANS AND ALASKA PENINSULA
AREAS THROUGH SATURDAY DUE TO COLD AIR ADVECTION AND TROUGHING
FROM THE NORTH. HEAVY FREEZING SPRAY REMAINS IN MARINE AREAS
WHEREVER WINDS ARE GUSTY IN THE AFOREMENTIONED REGIONS. EXTREME
FREEZING SPRAY IS LIKELY ALONG THE ICE EDGE AND OUT OF BAYS AND
PASSES BY FRIDAY MORNING.
COLDER AIR WILL DIVE INTO THE SOUTHWEST MAINLAND THROUGH FRIDAY
DUE TO THE INFLUENCE OF THE ARCTIC LOW. LOW TEMPERATURES WILL ONCE
AGAIN PLUMMET INTO THE NEGATIVE TEENS FOR MUCH OF THE MAINLAND
AND POTENTIALLY THE NEGATIVE 20S FOR THE KUSKOKWIM DELTA AND LOWER
KUSKOKWIM VALLEY. GUSTY WINDS WILL ALLOW FOR VERY COLD WIND
CHILLS NEAR -40F IN THE KUSKOKWIM DELTA AND WESTERN CAPES. AS
SUCH, COLD WEATHER ADVISORIES HAVE BEEN ISSUED FOR THESE AREAS.
TEMPERATURES WILL BEGIN TO WARM BY SATURDAY AS THE UPPER LOW
EXITS. BY THIS AFTERNOON, A PERIOD OF SNOW SHOWERS IS LIKELY FROM
UNIMAK ISLAND TO NIKOLSKI. THESE SHOWERS COINCIDING WITH A PUSH
OF GUSTY NORTHERLY WINDS MAY PROMOTE BLOWING SNOW CONDITIONS FOR
THIS LATTER HALF OF THE WORK WEEK. REDUCTIONS IN VISIBILITY FROM
THIS BLOWING SNOW POTENTIAL WILL DEPEND ON LOCAL SNOWFALL RATES
AND WIND SPEEDS; WE WILL CONTINUE TO MONITOR THIS SYSTEM SO STAY
TUNED FOR UPDATES.
-JAR/CL
LONG TERM FORECAST (DAYS 4 THROUGH 7: SUNDAY THROUGH WEDNESDAY)
AN AREA OF HIGH PRESSURE PERSISTS ACROSS THE BERING SEA,
ALEUTIANS AND PRIBILOF ISLANDS FOR THE LONG-TERM. ACROSS THE FAR
WEST, RAIN/SNOW AND WINDS UP TO 40 MPH FROM FRONTAL PASSAGES WILL
MOVE AS FAR EAST AS ADAK AND ATKA. ACROSS SOUTHWEST MAINLAND, THE
EASTERN BERING SEA AND THE ALASKA PENINSULA, EXPECT NORTHERLY
FLOW TO PERSIST WITH SHORTWAVES TROUGHS THAT COULD BRING PERIODS
OF LIGHT SNOW SHOWERS. THESE SHOWERS WILL BE MORE PROBABLE NEAR
AND OFF THE ICE EDGE IN THE BERING, HIGHER ELEVATIONS, AND NEAR
COASTLINES. MODELS DIFFER WITH THE EAST/WEST EXTENT OF THIS FLOW
REGIME AND IT IS POSSIBLE (THOUGH LOW PROBABILITY) THAT SHOWERS
COULD MOVE AS FAR WEST AS THE PRIBILOF ISLANDS AT TIMES, THIS
WEEKEND, AND THE EASTERN ALEUTIANS NEAR UNALASKA/NIKOLSKI. WINDS
THROUGH THE EASTERN BERING SEA/BRISTOL BAY AND THROUGH THE TERRAIN
GAPS ALONG THE ALASKA PENINSULA WILL LIKELY CONTINUE TO REMAIN
GUSTY WITH THE COLD AIR ADVECTING ACROSS THE AREA.
OUT EAST TOWARDS MAINLAND SOUTHCENTRAL, LOW PRESSURE WILL REMAIN
IN THE GULF OF ALASKA THROUGH THE LONG-TERM PERIOD. THIS WILL
SUSTAIN COLD, DRY, NORTHERLY FLOW WITH ENHANCED GAP WINDS THROUGH
THE FAVORED TERRAIN AND PASSES. ANY SNOWFALL SHOULD REMAIN LIGHT
AND CONFINED PRIMARILY TO ALONG THE COAST AND COASTAL MOUNTAIN
RANGES. TEMPERATURES MAY START TO MODERATE A LITTLE BIT THIS
WEEKEND FOR SOUTHCENTRAL, BUT WILL STILL BE BELOW NORMAL FOR THIS
TIME OF YEAR.
AVIATION
PANC...MVFR CONDITIONS AND PERIODS OF LIGHT SNOW WILL PERSIST
THROUGH MUCH OF THE DAY THURSDAY AS A WEAKENING SURFACE LOW MOVES
INTO PRINCE WILLIAM SOUND. A SECONDARY AREA OF LOW PRESSURE
IMMEDIATELY SOUTH OF RESURRECTION BAY LATER THIS AFTERNOON WILL
KEEP VICINITY SNOW IN THE AREA INTO TONIGHT.
BL
CLICK HERE TO GO TO PREVIOUS BULLETINS.
Main Text Page