298  
FXUS63 KJKL 090917  
AFDJKL  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE JACKSON KY  
517 AM EDT TUE SEP 9 2025  
   
KEY MESSAGES
 
 
 
- BELOW NORMAL TEMPERATURES AND DRY WEATHER WILL PERSIST THROUGH  
TONIGHT.  
 
- TEMPERATURES WILL WARM TO NEAR NORMAL BY WEDNESDAY OR THURSDAY  
AND THEN PERSIST INTO EARLY NEXT WEEK WITH NO MEASURABLE  
RAINFALL EXPECTED.  
 

 
   
SHORT TERM
 
(TODAY THROUGH WEDNESDAY)  
ISSUED AT 517 AM EDT TUE SEP 9 2025  
 
EARLY THIS MORNING, RATHER BROAD UPPER TROUGHING EXTENDED FROM  
EASTERN PORTIONS OF CANADA ACROSS THE GREAT LAKES TO OH VALLEY TO  
SOUTHEAST BETWEEN UPPER RIDGING CENTERED OVER THE ATLANTIC  
NORTHEAST OF BERMUDA AND ANOTHER UPPER RIDGE EXTENDING FROM  
NORTHERN MEXICO AND THE SOUTHWEST CONUS INTO THE SOUTHERN PLAINS  
AND ALSO ACROSS THE ROCKIES TO THE CANADIAN ROCKIES. FURTHER WEST,  
ANOTHER UPPER TROUGH EXTENDS FROM BC SOUTH NEAR THE WEST COAST OF  
THE CONUS. AT THE SURFACE, A RIDGE OF SFC HIGH PRESSURE EXTENDS  
FROM THE NORTHEAST TO THE SOUTHERN APPALACHIANS TO GA WHILE A WEAK  
INVERTED TROUGH FEATURE AHEAD OF THE TROUGH AXIS TO THE WEST  
EXTENDS INTO EASTERN PARTS OF THE COMMONWEALTH FROM THE GULF  
COAST AND THERE ARE SOME LOWER CLOUDS ASSOCIATED WITH IT FROM THE  
SOUTHERN COUNTIES INT PARTS OF MIDDLE AND EASTERN TN. RECENT  
SATELLITE IMAGERY REVEALS VALLEY FOG IS PRESENT ESPECIALLY SOUTH  
OF OF I-64 IN THE RIVERS, FORKS, AND MAIN TRIBUTARIES OF THE KY,  
CUMBERLAND, AND BIG SANDY BASIN. THIS FOG MAY BE DENSE IN A FEW  
SPOTS AT PRESENT. TEMPERATURES RANGED FROM THE MID 40S IN THE  
NORMALLY COLDER VALLEY LOCATIONS TO THE MID 50S ON THE RIDGES.  
 
TODAY AND TONIGHT, A MOISTURE STARVED SHORTWAVE TROUGH IS  
EXPECTED TO MOVE INTO THE LOWER OH VALLEY AS UPPER TROUGHING  
PERSISTS FROM NEAR HUDSON AND JAMES BAY INTO THE GREAT LAKES TO  
EASTERN CONUS BETWEEN THE RIDGING IN THE ATLANTIC CENTERED EAST  
AND NORTHEASTER OF BERMUDA AND UPPER LEVEL RIDGING THAT AXIS OF  
WHICH SHIFTS EAST TO THE SOUTHERN PLAINS TO HIGH PLAINS TO PARTS  
OF THE CENTRAL AND NORTHERN PLAINS. GUIDANCE GENERALLY HAS THE  
AXIS OF THE SFC HIGH PRESSURE RIDGE EXTENDING FROM THE NORTHEAST  
INTO THE SOUTHEAST SHIFTING A BIT TO THE WEST AND NORTHWEST INTO  
EASTERN KY THROUGH TODAY AND TONIGHT WHILE THE INVERTED TROUGH  
SHIFTS WEST AND NORTHWEST OF EASTERN KY. VALLEY FOG SHOULD LIFT  
AND DISSIPATE WITHIN ABOUT 2 TO 3 HOURS AFTER SUNRISE OR THROUGH  
THE 9 AM TO 10 EDT TIMEFRAME THIS MORNING. WITH THE INVERTED  
TROUGH ACROSS THE AREA SOME LOW TO MID LEVEL CLOUDS WILL BE  
POSSIBLE AT TIMES TODAY. OTHERWISE, TEMPERATURES WILL MODERATE  
ABOUT 3 OR SO DEGREES ON AVERAGE COMPARED TO MONDAY. VALLEY FOG IS  
AGAIN FAVORED TONIGHT WITH ANOTHER SMALL TO MODERATE RIDGE/VALLEY  
TEMPERATURE SPLIT. MID TO UPPER 40S ARE ANTICIPATED FOR THE  
VALLEYS FOR LOW WITH 50S ELSEWHERE.  
 
WEDNESDAY, A SHORTWAVE TROUGH SHOULD WORK ACROSS THE COMMONWEALTH  
INCLUDING EASTERN KY BUT WILL BE MOISTURE STARVED AND SHOULD  
PRODUCE LITTLE MORE THAN A FEW CLOUDS AT TIMES. A MORE SIGNIFICANT  
BUT ALSO MOISTURE DEPRIVED SHORTWAVE SHOULD MOVE TO THE CENTRAL  
GREAT LAKES TO MID MS VALLEY BY LATE WEDNESDAY. A RIDGE OF SFC  
HIGH PRESSURE SHOULD REMAIN ACROSS THE APPALACHIANS AND OH VALLEY  
FOR WEDNESDAY. TEMPERATURES SHOULD MODERATE ANOTHER COUPLE OF  
DEGREES AND NEAR NORMALS FOR THIS TIME OF YEAR FOR HIGHS.  
   
LONG TERM
 
(WEDNESDAY NIGHT THROUGH MONDAY)  
ISSUED AT 500 AM EDT TUE SEP 9 2025  
 
THE PERIOD IS EXPECTED TO BEGIN WITH AN UPPER LEVEL RIDGE CENTERED  
EAST AND NORTHEAST OF BERMUDA WITH ANOTHER UPPER LEVEL RIDGE  
EXTENDING FROM MEXICO ACROSS PORTIONS OF THE SOUTHERN PLAINS AND  
SOUTHERN ROCKIES INTO THE CENTRAL AND NORTHERN PLAINS TO MANITOBA.  
IN BETWEEN, AN UPPER LEVEL TROUGH IS EXPECTED TO EXTEND SOUTH  
ACROSS THE GREAT LAKES TO LOWER OH VALLEY TO THE SOUTHEAST FROM AN  
UPPER LEVEL LOW IN QUEBEC WHILE AN UPPER LEVEL LOW AND TROUGH IS  
EXPECTED OVER THE WESTERN CONUS. ALSO AT THAT POINT, AN UPPER  
LEVEL LOW AND TROUGH IS EXPECTED TO BE LOCATED WEST AND NORTHWEST  
OF HUDSON BAY WHILE ANOTHER TROUGH IS EXPECTED TO EXTEND FROM THE  
GULF OF AK VICINITY INTO PARTS OF THE EASTERN PACIFIC. AT THE  
SURFACE, A RIDGE OF SFC HIGH PRESSURE IS EXPECTED TO EXTEND FROM  
THE CENTRAL AND SOUTHERN APPALACHIANS TO THE LOWER OH VALLEY AND  
ALSO INTO THE SOUTHEAST AS WELL AS SOUTHERN GREAT LAKES.  
 
WEDNESDAY NIGHT TO THURSDAY NIGHT, THE CONSENSUS OF GUIDANCE IS  
FOR THE UPPER LOW INITIALLY CENTERED OVER QUEBEC TO MOVE TO THE  
MARITIMES WHILE THE TRAILING TROUGH AT 500 MB CROSSES THE EASTERN  
GREAT LAKES AS WELL AND THE LOWER OH VALLEY AND APPALACHIANS AND  
MOVES INTO THE NORTHEAST TO MID ATLANTIC TO SOUTHEAST. MEANWHILE,  
UPPER LEVEL RIDGING SHOULD BUILD INTO THE GREAT LAKES TO MID MS  
VALLEY REGIONS BEHIND THIS TROUGH. FURTHER WEST, AN UPPER  
TROUGH/LOW MEANDERS ACROSS THE WESTERN CONUS AND AN UPPER TROUGH  
MOVES TO THE HUDSON TO JAMES BAY TO NORTHERN ONTARIO AREAS. EVEN  
FURTHER WEST, ANOTHER UPPER TROUGH IS PROGGED TO APPROACH THE BC  
COAST TO PACIFIC NORTHWEST COAST. CLOSER TO HOME, THE UPPER  
TROUGH WILL BE VERY MOISTURE STARVED AS IT WORKS ACROSS EASTERN KY  
WITH A RIDGE OF SFC HIGH PRESSURE REMAINING IN PLACE ACROSS THE  
APPALACHIANS. GUIDANCE HAS LIMITED MOISTURE BETWEEN 850 AND 700 MB  
WITH THIS SYSTEM WITH MOISTURE MORE SCANT THAN THAT BETWEEN 700  
MB AND 500 MB WITH LITTLE OR NO QPF ACROSS EASTERN KY AS IT  
PASSES. SOME NON MEASURABLE SPRINKLES CANNOT BE COMPLETELY RULED  
OUT FROM MID LEVEL CLOUDS LATE WED NIGHT INTO THU AS THIS SYSTEM  
PASSES EASTERN KY, BUT CONFIDENCE IN THAT WAS NOT HIGH ENOUGH TO  
INCLUDE AT THIS JUNCTURE. TEMPERATURES SHOULD MODERATE A COUPLE  
MORE DEGREES TO NEAR NORMAL, PARTICULARLY FOR HIGH TEMPERATURES  
ON THURSDAY.  
 
FRIDAY TO SATURDAY NIGHT, THE UPPER LEVEL RIDGE IS PROGGED TO  
BUILD INTO THE OH VALLEY TO SOUTHERN APPALACHIANS TO LOWER MS  
VALLEY REGION FROM THE SOUTHERN PLAINS/ARKLATEX REGION. FURTHER  
NORTH THE UPPER LOW SHOULD WORK FROM THE HUDSON/JAMES BAY TO  
NORTHERN ONTARIO AREA INTO QUEBEC TO THE NORTHERN TO EASTERN GREAT  
LAKES. ACROSS THE WESTERN CONUS, THE INITIAL UPPER TROUGH/LOW  
SHOULD MOVE TO THE ALBERTA/NORTHERN ROCKIES TO CENTRAL AND  
NORTHERN PLAINS AS THE NEXT SHORTWAVE NEARS THE WEST COAST OF THE  
CONUS. GRADUAL HEIGHT RISES AT 500 MB SHOULD ENSUE FOR FRIDAY  
INTO SATURDAY ACROSS EASTERN KY. THE 00Z ECMWF OPERATIONAL RUN IS  
MORE SIMILAR TO THE RECENT GFS OPERATIONAL RUNS WITH THE UPPER  
LEVEL PATTERN FROM EASTERN CANADA TO THE GREAT LAKES INTO THE  
EASTERN CONUS COMPARED TO THE 12Z/8TH ECMWF OPERATIONAL RUN AND  
SOME PREVIOUS ECMWF OPERATIONAL RUNS. THIS LEADS TO LESS THAN  
AVERAGE CONFIDENCE IN THE EVOLUTION OF THE UPPER PATTERN BY LATE  
SATURDAY AND CONTINUING SUNDAY AND EARLY NEXT WEEK. NEAR NORMAL  
TEMPERATURES ARE FORECAST TO BEGIN THE WEEKEND ALONG WITH RAIN  
FREE WEATHER.  
 
SUNDAY TO MONDAY, EVEN THOUGH THE MOST RECENT OPERATIONAL ECMWF  
RUN IS GENERALLY MORE SIMILAR TO RECENT GFS RUNS WITH THE UPPER  
PATTERN OVER THE EASTERN CONUS TO END THE WEEKEND INTO EARLY NEXT  
WEEK COMPARED TO SOME OF THE PREVIOUS ECMWF RUNS, CONFIDENCE IS  
LOWER THAN AVERAGE TO END THE PERIOD. THESE DIFFERENCES LEAD TO  
CONSIDERABLE DIFFERENCES IN FORECAST CLOUD COVER AND TEMPERATURES  
AND PERHAPS LOW CHANCES FOR CONVECTION. THE NBM TEMPERATURE  
FORECASTS GENERALLY SPLIT THE DIFFERENCE BETWEEN SOLUTIONS TO END  
THE WEEKEND AND BEGIN NEXT WEEK. HOWEVER, IF THE RECENT GFS  
RUNS WERE TO VERIFY WITH 500 MB HEIGHTS NEAR 590 DM FOR MONDAY  
COMPARED TO AROUND 585 DM 500 MB HEIGHTS OF THE ECMWF,  
TEMPERATURES FOR HIGHS BY MONDAY WOULD BE SEVERAL DEGREES ABOVE  
NORMAL AS COMPARED TO THE CURRENT NEAR NORMAL FORECAST. OVERALL,  
DRY WEATHER SHOULD CONTINUE.  
 

 
   
AVIATION
 
(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)  
ISSUED AT 227 AM EDT TUE SEP 9 2025  
 
VFR WAS REPORTED AT THE TAF SITES AT ISSUANCE TIME WITH VFR FOR  
MOST AWOS AND ASOS SITES ACROSS THE REGION. SATELLITE IMAGERY  
REVEALS VALLEY FOG PRESENT IN PARTS OF THE KY, CUMBERLAND, AND BIG  
SANDY RIVER BASIN NOT AFFECTING THE TAF SITES. PER WEBCAM IMAGERY  
REDUCTIONS ARE LIKELY IFR IF NOT LIFR AND VLIFR IN SOME LOCATIONS.  
THIS FOG MAY INCREASE IN COVERAGE OVERNIGHT, BEFORE LIFT AND  
DISSIPATING IN ALL AREAS BY THE 13Z TO 14Z TIMEFRAME. AT THIS  
POINT, OPTED FOR PERSISTENCE OF THIS NOT AFFECTING THE 5 TAF  
SITES. A BREIF PERIOD OF REDUCTIONS AFFECTING KSME CANNOT BE  
COMPLETELY RULED OUT AS GFS LAMP THERE CONTINUES TO CARRY SOME  
REDUCTIONS TO MVFR AND IFR OVERNIGHT THOUGH IS LIKELY OVERDONE.  
OTHERWISE, VFR CONDITIONS SHOULD RETURN TO ALL AREAS BY AROUND 14Z  
AND REMAIN THROUGH ABOUT 04Z WHEN FOG MAY BEGIN TO DEVELOP IN  
VALLEYS ONCE AGAIN. WINDS LESS THAN 10 KTS ARE FORECAST THROUGH  
THE PERIOD.  
 

 
   
JKL WATCHES/WARNINGS/ADVISORIES
 
 
NONE.  
 

 
 

 
 
SHORT TERM...JP  
LONG TERM...JP  
AVIATION...JP  
 
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