843  
FXAK68 PAFC 060054  
AFDAFC  
 
SOUTHCENTRAL AND SOUTHWEST ALASKA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE ANCHORAGE AK  
454 PM AKDT SAT JUL 5 2025  
 
.SHORT TERM FORECAST SOUTHCENTRAL ALASKA (DAYS 1 THROUGH 3/TODAY  
THROUGH MONDAY NIGHT)...  
 
UPPER LEVEL RIDGING OVER INTERIOR ALASKA HAS ONCE AGAIN HELPED TO  
CLEAR OUT MORNING CLOUD COVER OVER THE COPPER RIVER BASIN. CLOUD  
COVER HAS BEEN MORE PERSISTENT OVER THE TALKEETNAS AND NORTHERN  
SUSITNA VALLEY AND HAS SUBSEQUENTLY KEPT TEMPERATURES SLIGHTLY  
COOLER. REGARDLESS OF THE CLOUDS, DAYTIME TEMPERATURES HAVE WARMED  
INTO THE UPPER 60S AND LOWER 70S ACROSS MUCH OF THE REGION.  
PRINCE WILLIAM SOUND AND COASTAL AREAS CONTINUE TO BE THE COOL  
LOCALES WITH TEMPERATURES IN THE 50S. FOR THE REST OF THIS  
AFTERNOON, STRONG DAYTIME HEATING AND THE PASSAGE OF ANOTHER  
SHORTWAVE TROUGH WILL CONTRIBUTE TO DESTABILIZATION OF THE  
ATMOSPHERE OVER NORTHERN PORTIONS OF SOUTHCENTRAL. ISOLATED TO  
WIDELY SCATTERED WET THUNDERSTORMS AND CONVECTIVE SHOWERS ARE  
ANTICIPATED OVER THE SUSITNA VALLEY AND COPPER BASIN THROUGH THE  
EVENING HOURS.  
 
MEANWHILE, COASTAL RIDGING DOWNSTREAM OF AN APPROACHING FRONT AND  
WARMER INTERIOR TEMPERATURES WILL SEE A TIGHTENED PRESSURE  
GRADIENT WITH INCREASING GAP WINDS THROUGH SOUTHCENTRAL FOR THE  
REST OF TODAY. THE COPPER RIVER WIND AND KNIK RIVER WIND COULD SEE  
GUSTS AS HIGH AS 35 MPH THIS AFTERNOON AND EVENING WHILE GUSTS  
THROUGH THE TURNAGAIN ARM COULD GUST ANYWHERE FROM 30 TO 40 MPH.  
 
THE DRIEST LOCATION ACROSS SOUTHCENTRAL IS NEAR THE TOK CUTOFF,  
WHERE TEMPERATURES ARE ALREADY IN THE MID TO UPPER 70S WITH RH  
VALUES NEAR OR JUST BELOW 30 PERCENT. INCREASING WINDS GUSTING TO  
15 TO 20 MPH MAY BRIEFLY RESULT IN HOT-DRY-WINDY CONDITIONS LATER  
THIS EVENING, BUT RH VALUES AT OR ABOVE 25 PERCENT WILL QUICKLY  
REBOUND WITH THE LOSS OF DAYTIME HEATING. AS MENTIONED IN THE  
PREVIOUS DISCUSSION, SHOWERS WILL LIKELY KEEP GOING THROUGH THE  
OVERNIGHT HOURS FOR THE TALKEETNA MOUNTAINS AND NORTHERN SUSITNA  
VALLEY WITH THE SLOW DEPARTURE OF THE SHORTWAVE TROUGH TONIGHT.  
FURTHER SOUTH, A TROUGH OVER THE WESTERN GULF WILL STRUGGLE TO  
LIFT NORTHWARD TOWARD SOUTHCENTRAL, KEEPING RAIN CONFINED TO  
KODIAK ISLAND AND THE GULF FOR THE REMAINDER OF TODAY.  
 
SUNDAY WILL BE A TRANSITION DAY AS THE RIDGE WEAKENS TO THE NORTH  
AND THE UPPER LOW SHIFTS INTO THE GULF, WITH SHORT-WAVES ROTATING  
NORTHWARD TOWARD SOUTHCENTRAL. INCREASED CLOUD COVER WILL LEAD TO  
SOMEWHAT MORE STABLE CONDITIONS INLAND, WITH MUCH LESS CONVECTION  
EXPECTED. STEADY RAIN WILL SETTLE IN ALONG THE NORTH GULF COAST  
AND PRINCE WILLIAM SOUND. SHORT-WAVES WILL THEN ROTATE NORTHWARD  
INTO SOUTHCENTRAL SUNDAY NIGHT THROUGH MONDAY, THOUGH MODEL  
GUIDANCE VARIES ON THE EXACT TRACK OF SHORT-WAVES. RAIN IS LIKELY  
AHEAD OF THE SHORT-WAVES, ESPECIALLY FROM PRINCE WILLIAM SOUND TO  
THE COPPER RIVER BASIN. THE BIG QUESTION IS HOW FAR WEST RAIN WILL  
MAKE IT, AS THE UPPER LOW IN THE GULF WILL CONTINUE EASTWARD  
TOWARD SOUTHEAST ALASKA, CAUSING FLOW OVER SOUTHCENTRAL TO SHIFT  
TOWARD NORTHERLY AND CHANGE THE DIRECTION OF FLOW (AND MOVEMENT OF  
SHORT-WAVES). STAY TUNED, AS THERE IS POTENTIAL FOR WIDESPREAD  
WETTING RAINS TO START THE WORK WEEK.  
 
FORECAST CONFIDENCE CONTINUES TO FALL MONDAY NIGHT INTO TUESDAY  
AS AN ARCTIC TROUGH DIGS SOUTHWARD ACROSS MAINLAND ALASKA. MODEL  
GUIDANCE CONTINUES TO STRUGGLE WITH THE ULTIMATE TRACK AND  
AMPLITUDE OF THE ARCTIC TROUGH, WITH INDIVIDUAL SHORT-WAVES  
LEADING TO WILDLY DIFFERENT SOLUTIONS AMONG THE GUIDANCE. THE  
LIKELY BET IS THAT UNSETTLED WEATHER WILL PERSIST AS WE CONTINUE  
THROUGH THE WORK WEEK.  
 
-SEB/BL  
 
 
 
.SHORT TERM FORECAST SOUTHWEST ALASKA/BERING SEA/ALEUTIANS (DAYS  
1 THROUGH 3: TODAY THROUGH WEDNESDAY)...  
 
CURRENTLY, THERE IS A LARGE LOW OVER THE EAST ALEUTIANS/ALASKA  
PENINSULA REGION. THIS IS BRINGING RAINFALL AND GUSTY WINDS TO  
BRISTOL BAY AND THE ALASKA PENINSULA. ATTENTION SHIFTS THE  
KUSKOKWIM DELTA AND THE LOWER KUSKOKWIM VALLEY OVER THE EVENING AS  
A WAVE PASSES THROUGH AND KICKS OFF CHANCES FOR THUNDERSTORMS. THE  
LOWER KUSKOKWIM VALLEY WILL HAVE THE BEST CHANCES FOR  
THUNDERSTORMS WITH THIS WAVE. IN THE KUSKOKWIM VALLEY,  
THUNDERSTORMS WILL BE MOST LIKELY NORTH OF ANIAK AND BETHEL.  
THE BETHEL AND ANIAK COMMUNITIES WILL LIKELY STAY IN A STRATIFORM  
RAINFALL REGION. THERE IS UNCERTAINTY IN EXACTLY WHERE AND IF THE  
THUNDERSTORMS WILL FORM WITH SOME MODELS BRINGING THEM FURTHER  
SOUTH OR NORTH. RAIN CHANCES WILL CONTINUE IN THE AFOREMENTIONED  
REGIONS THOUGH SUNDAY EVENING. THE SOUTHWEST MAINLAND DRIES OUT  
ON MONDAY AS SLACK FLOW BUILDS IN. WINDS BECOME LIGHT AND  
PRECIPITATION CHANCES DIMINISH, LASTING THROUGH WEDNESDAY.  
HOWEVER, CHANCES FOR THUNDERSTORMS REMAIN IN THE LOWER KUSKOKWIM  
DELTA, PARTICULARLY CLOSER TO THE ALASKA RANGE.  
 
THE BERING WILL BE FAIRLY ACTIVE. A FRONT FROM A LOW IN THE NORTH  
PACIFIC WILL ENTER THE WESTERN ALEUTIANS ON SUNDAY. RAINFALL AND  
GUSTY WINDS WILL ACCOMPANY THE LOW AS IT TRACKS EASTWARD. THE LOW  
WILL STRENGTHEN AS IT MOVES EAST, EVENTUALLY REACHING THE EASTERN  
ALEUTIANS BY WEDNESDAY. ANOTHER BOUT OF RAINFALL AND GUSTY WINDS  
WILL IMPACT THE EASTERN ALEUTIANS AND ALASKA PENINSULA REGION  
ONCE THE LOW ARRIVES. THERE IS DECENT MODEL AGREEMENT ON THIS  
SCENARIO, SO CONFIDENCE IS INCREASED.  
 
-JAR  
 
 
   
LONG TERM FORECAST (DAYS 4 THROUGH 7: WEDNESDAY THROUGH SATURDAY)  
 
THE LONG-TERM PERIOD BEGINS WITH A SHORTWAVE RIDGE OVER  
SOUTHCENTRAL ALASKA, WEAK FLOW ACROSS SOUTHWEST ALASKA, AND A  
NORTH PACIFIC LOW SOUTH OF THE EASTERN ALEUTIANS AND SOUTHERN  
ALASKA PENINSULA (AKPEN). THE RIDGE OVER SOUTHCENTRAL WEDNESDAY  
LOOKS TO MOVE NORTHWARD AND REORIENT WITH A MORE EAST TO WEST AXIS  
ACROSS THE CENTRAL INTERIOR BY THURSDAY. THIS WILL OPEN THE DOOR  
FOR THE NORTH PACIFIC LOW TO MOVE INTO THE GULF OF ALASKA BY  
THURSDAY. WETTEST LOCATIONS LOOK TO BE ACROSS KODIAK ISLAND, THE  
EASTERN KENAI PENINSULA, AND PRINCE WILLIAM SOUND WITH SCATTERED  
SHOWERS FOR SOUTHWEST AND INTERIOR SOUTHCENTRAL. STEADY RAINS  
ACROSS THE SOUTHCENTRAL COAST TAPER OFF TO A MORE SHOWERY REGIME  
FRIDAY AND SATURDAY VERY MUCH LIKE INLAND LOCATIONS AS THE LOW  
WEAKENS AND ENERGY GOES TO SOUTHEAST ALASKA.  
 
FURTHER TO THE WEST, AN UPPER LEVEL SHORTWAVE LOOKS TO DIG  
SOUTHWARD FROM NORTHERN KAMCHATKA INTO THE CENTRAL BERING BY  
THURSDAY. RAIN LOOKS TO BE MOSTLY CONFINED TO THE BERING BUT MAY  
MAKE IT AS FAR SOUTH AS THE PRIBILOF ISLANDS AND AS FAR EAST AS  
NUNIVAK ISLAND. ELSEWHERE, A RIDGE ACROSS THE WESTERN BERING WILL  
WEAKEN INTO THURSDAY AND ALLOW FOR A FEW WEAK SYSTEMS TRACKING  
SOUTHEASTWARD FROM SOUTHERN KAMCHATKA TO MOVE OVER THE WESTERN  
ALEUTIANS AND BERING BY FRIDAY. RAIN WITH THESE SYSTEMS WILL BE  
LIGHT. THE RIDGE LOOKS TO BUILD BACK ACROSS THE WESTERN BERING BY  
SATURDAY. CONFIDENCE REMAINS LOW AND UNCERTAINTY REMAINS HIGH  
REGARDING THE TRACK OF A NORTH PACIFIC LOW THURSDAY THROUGH  
SATURDAY. SOME GUIDANCE KEEPS THE LOW SOUTH OF THE ALEUTIAN CHAIN  
(CANADIAN AND SOMEWHAT THE ECMWF) WHILE SOME GUIDANCE WANTS TO  
CLIP THE CENTRAL/EASTERN ALEUTIANS AND SOUTHERN AKPEN WITH THE  
FRONT BRINGING ANOTHER ROUND OF LIGHT RAIN TO THOSE AREAS.  
 
.AVIATION...  
 
PANC...VFR CONDITIONS WILL PERSIST. THERE IS HIGH CONFIDENCE IN  
STRONG GUSTY SOUTHEASTERLY WINDS DEVELOPING LATER THIS AFTERNOON  
THROUGH THE TURNAGAIN ARM AND BENDING INTO THE TERMINAL AT  
TIMES. GUSTS OF 30 TO 35 KTS ARE POSSIBLE THROUGH ABOUT 09-10Z  
SUNDAY THEN ARE EXPECTED TO QUICKLY SHUT OFF AS WINDS TURN DOWN  
INLET. ISOLATED TO SCATTERED SHOWERS ARE POSSIBLE THROUGH THE  
PERIOD ALONG THE CHUGACH MOUNTAINS AND POSSIBLY WORKING INTO THE  
VICINITY OF THE TERMINAL.  
 
 
 
 
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