597  
FXUS63 KJKL 121019  
AFDJKL  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE JACKSON KY  
619 AM EDT FRI SEP 12 2025  
   
KEY MESSAGES
 
 
 
- DRY WEATHER IS EXPECTED TO PERSIST FOR THE NEXT WEEK.  
 
- TEMPERATURES SHOULD WARM ABOVE NORMAL TODAY AND REMAIN NEAR THAT  
LEVEL WELL INTO NEXT WEEK.  
 

 
   
SHORT TERM
 
(TODAY THROUGH SATURDAY)  
ISSUED AT 600 AM EDT FRI SEP 12 2025  
 
EARLY THIS MORNING, THE AXIS OF AN UPPER LEVEL TROUGH EXTENDED  
FROM THE NORTHEAST INTO PORTIONS OF THE SOUTHEAST EAST OF THE  
CREST OF THE APPALACHIANS AND EASTERN KY. TO THE WEST, AN UPPER  
LEVEL RIDGE EXTENDED FROM MEXICO ACROSS THE SOUTHERN PLAINS TOT  
HE UPPER MS VALLEY TO CENTRAL GREAT LAKES. AN UPPER LEVEL TROUGH  
CONTINUES TO GRADUALLY EVOLVE OVER THE WESTERN CONUS WHILE AN  
UPPER LEVEL LOW WAS OVER NORTHERN HUDSON BAY WITH A SHORTWAVE  
TROUGH SOUTH INTO NORTHERN ONTARIO. AT THE SURFACE, A RIDGE OF  
HIGH PRESSURE EXTENDED FROM QUEBEC TO THE OH AND TN VALLEYS.  
MOSTLY CLEAR TO CLEAR SKIES OVERNIGHT AND LIGHT WINDS HAVE LED TO  
THE DEVELOPMENT OF RIVER VALLEY FOG OVER MUCH OF THE BIG SANDY,  
KY, AND CUMBERLAND BASINS WITH PATCHY FOG ALSO EVIDENT IN PORTIONS  
OF THE LIKING RIVER VALLEY AS WELL PER SATELLITE. IN A FEW SPOTS  
THIS FOG IS LIKELY TO HAVE BECOME DENSE. RECENTLY OBSERVED  
TEMPERATURES RANGED FROM THE LOW 50S IN THE DEEPER SHELTERED  
VALLEYS TO THE UPPER 50S TO LOW 60S ON RIDGES.  
 
TODAY AND TONIGHT, A GRADUAL INCREASE IN 500 MB HEIGHTS IS  
ANTICIPATED TODAY WITH NEAR NEUTRAL HEIGHT TENDENCIES TONIGHT  
WITH THIS OCCURRING AS THE UPPER TROUGH CURRENTLY EAST OF EASTERN  
KY MOVES TO NEAR THE EASTERN SEABOARD AND UPPER LEVEL RIDGING  
REMAINS FROM THE SOUTHERN PLAINS TO MS VALLEY REGIONS AND ALSO  
EAST INTO THE SOUTHERN AND CENTRAL APPALACHIANS. FURTHER NORTH,  
THE UPPER LOW INITIALLY OVER HUDSON BAY IS PROGGED TO MOVE INTO  
QUEBEC WITH THE TRAILING SHORTWAVE TROUGH WORKING INTO THE GREAT  
LAKES. THE RIDGE OF SFC HIGH PRESSURE WILL CONTINUE TO REMAIN  
ACROSS THE REGION. VALLEY FOG SHOULD GRADUALLY LIFT AND DISSIPATE  
THROUGH AROUND 10 AM EDT OR ABOUT 2 TO 3 HOURS PAST SUNRISE TODAY  
AND GIVE WAY TO MOSTLY SUNNY TO SUNNY SKIES. TEMPERATURES SHOULD  
CONTINUE THE UPWARD TREND OF THE PAST FEW DAYS TO A COUPLE OF  
DEGREES ABOVE NORMAL WITH LOW TO MID 80S FOR ALL AREAS OUTSIDE OF  
ELEVATIONS ABOVE 2000 FEET. NORMAL HIGHS FOR TODAY 80 AT JACKSON  
AND 81 FOR LONDON. UNDER HIGH PRESSURE TONIGHT, LIGHT WINDS AND  
MOSTLY CLEAR TO CLEAR SKIES WILL AGAIN FAVOR VALLEY FOG  
DEVELOPMENT ALONG THE LARGER CREEKS, AREA RIVERS, AND LAKES.  
ANOTHER MODERATE MAGNITUDE RIDGE/VALLEY TEMPERATURE SPLIT IS  
ANTICIPATED WITH THE NORMALLY COLDER LOCATIONS BOTTOMING OUT  
AROUND 50 WITH UPPER 50S FOR THE COALFIELD RIDGES.  
 
ON SATURDAY, A SLIGHT DECREASE IN 500 MB IS ANTICIPATED AS THE  
UPPER TROUGH OVER EASTERN CANADA TO THE GREAT LAKES PASSES BY TO  
THE NORTH AND NORTHEAST OF EASTERN KY. AT THE SAME TIME, THE  
UPPER HIGH SHOULD REMAIN FROM NORTHERN MEXICO AND THE SOUTHERN  
PLAINS INTO THE MS VALLEY REGION AND PORTIONS OF THE SOUTHEAST  
ALTHOUGH WEAKEN. THE ASSOCIATED SFC HIGH PRESSURE RIDGE SHOULD  
REMAIN ACROSS THE APPALACHIAN REGION. HIGHS FOR SATURDAY SHOULD  
BE SIMILAR TO TODAY IF NOT A DEGREE OR SO WARMER. WITH THE  
SHORTWAVE PASSING TO THE NORTH AND NORTHEAST SOME HIGH AND MID  
LEVEL CLOUD COVER SHOULD SPREAD INTO THE AREA DURING THE  
AFTERNOON.  
   
LONG TERM
 
(SATURDAY NIGHT THROUGH THURSDAY)  
ISSUED AT 545 AM EDT FRI SEP 12 2025  
 
THE PERIOD IS EXPECTED TO BEGIN WITH THE AXIS OF AN UPPER LEVEL  
RIDGE EXTENDING FROM MEXICO ACROSS THE SOUTHERN PLAINS TO THE MID  
MS VALLEY TO UPPER MS VALLEY TO ONTARIO WITH RIDGING ALSO  
EXTENDING INTO THE LOWER OH VALLEY/APPALACHIANS. A WEAK LINGERING  
TROUGH IS EXPECTED TO EXTEND FROM COAST VA AND THE COAST OF THE  
CAROLINAS TO OFF THE GA COAST TO FL WHILE A MORE POTENT ROUGH  
SHOULD EXTEND FROM QUEBEC TO THE NORTHEAST. FURTHER WEST, AN UPPER  
TROUGH SHOULD EXTEND FROM ALBERTA TO THE ROCKIES/FOUR CORNERS  
REGION WITH ANOTHER SERIES OF SHORTWAVES OVER THE PACIFIC HEADED  
TOWARD BC AND THE PACIFIC NORTHWEST. AT THE SURFACE, A RIDGE OF  
HIGH PRESSURE SHOULD EXTEND FROM THE MID ATLANTIC STATES TO THE  
LOWER MS VALLEY/NORTHERN GULF AS THE PERIOD BEGINS.  
 
FROM SATURDAY NIGHT TO SUNDAY NIGHT, GUIDANCE GENERALLY LINGERS  
AN UPPER LEVEL TROUGH FROM THE VA COAST TO FL WHILE TRACKING THE  
UPPER TROUGH INITIALLY FROM QUEBEC TO THE GREAT LAKES THE EASTERN  
GREAT LAKES AND ST LAWRENCE VALLEY TO THE MARITIMES AND ACROSS  
SECTIONS OF THE NORTHEAST. MEANWHILE, THE UPPER RIDGE CENTERED  
OVER NORTHERN MEXICO TO THE SOUTHERN PLAINS BUILDS INTO THE GREAT  
LAKES TO MS VALLEY. ACROSS EASTERN KY THIS UPPER PATTERN ALONG  
WITH SFC HIGH PRESSURE REMAINING ACROSS THE APPALACHIANS WILL  
SUPPORT MILD/ABOVE NORMAL TEMPERATURES, ESPECIALLY FOR HIGHS ON  
SUNDAY WITH VALLEY FOG AND A MODERATE MAGNITUDE RIDGE/VALLEY  
TEMPERATURE SPLIT FAVORED BOTH SATURDAY AND SUNDAY NIGHTS.  
 
MONDAY TO TUESDAY NIGHT, GUIDANCE BEGINS TO DIVERGE EARLY NEXT  
WEEK DOWNSTREAM OF AN UPPER LEVEL RIDGE EXTENDING FROM THE  
SOUTHERN PLAINS INTO THE MID MS VALLEY AND GREAT LAKES AS FAR AS  
HOW LINGERING TROUGHING NEAR THE EASTERN SEABOARD EVOLVES. RECENT  
GFS RUNS KEEP MORE OF AN OPEN WAVE/500 MB TROUGH AXIS NEAR THE  
EASTERN SEABOARD WHILE ECMWF RUNS TEND TO CLOSE OFF AN UPPER LOW  
OVER SC AND GA AND TRACK THIS SYSTEM TO NEAR THE GA AND AL BORDER  
AS MID WEEK APPROACHES. AS IS THE CASE AT MIDWEEK TO THE END OF  
THE PERIOD, THE GFS WOULD BE A WARMER, SUNNIER, AND ENTIRELY DRY  
SOLUTION WITH UPPER LEVEL AND SFC RIDGING DOMINATING. MEANWHILE,  
THE ECMWF BRING AND INCREASE IN MOISTURE INTO THE SOUTHERN TO  
CENTRAL APPALACHIANS INCLUDING EASTERN KY BY LATE TUESDAY NIGHT  
THOUGH PRECIPITATION IS GENERALLY CONFINED TO NEAR THE CREST OF  
THE APPALACHIANS/BLUE RIDGE EAST AND SOUTHEAST. POPS FROM NBM  
PPI/POP OF LESS THAN 10 PERCENT WERE MAINTAINED DURING THIS  
TIMEFRAME WITH THE NBM GENERALLY MIDDLE OF OF THE ROAD  
TEMPERATURES BY THE TUESDAY TO TUESDAY NIGHT TIMEFRAME MAINTAINED.  
IF THE GFS SOLUTION WERE TO VERIFY, TEMPERATURES WOULD BE ON THE  
ORDER OF 5 OR MORE DEGREES ABOVE NORMAL VERSUS THE CURRENTLY  
FORECAST COUPLE OF DEGREE ABOVE NORMAL HIGH TEMPERATURES FOR  
TUESDAY.  
 
WEDNESDAY TO THURSDAY, AS THE PERIOD ENDS, THE RECENT GUIDANCE  
VARIES SEVERAL DM WITH 500 HEIGHTS ACROSS THE APPALACHIANS AND  
EASTERN KY AREAS. THE PAST COUPLE OF GFS OPERATIONAL RUNS ARE  
GENERALLY FURTHER EAST AND CLOSER TO OR EAST OF THE SOUTHEAST US  
COAST WITH AN UPPER TROUGH/BROAD UPPER LEVEL LOW WITH EASTERN KY  
NEARER TO THE AXIS OF UPPER LEVEL RIDGING AT MIDWEEK. MEANWHILE,  
THE RECENT ECMWF OPERATIONAL RUNS HAVE AN UPPER LOW CENTERED OVER  
THE SOUTHEAST VICINITY OF ATL AND EXTENDING INTO THE SOUTHERN  
APPALACHIANS NEAR DAWN ON WEDNESDAY. THE RECENT GFS RUNS KEEP  
HIGHER HEIGHTS/UPPER RIDGING THE DOMINANT INFLUENCE ON THE WEATHER  
OVER EASTERN KY TO END THE PERIOD WHILE RECENT ECMWF RUNS HAVE  
THE UPPER LOW/OPEN WAVE OVER THE SOUTHEAST IF NOT TRACKING IT INTO  
THE APPALACHIANS AS IS THE CASE WITH THE 00Z ECMWF OPERATIONAL  
RUN WITH THE 00Z ENS MEAN SIMILAR. AT THE VERY LEAST, THIS LEADS  
TO UNCERTAINTY IN TEMPERATURES AND CLOUD COVER, WHILE THE 00Z  
ECMWF AND ENS MEANS SUGGEST SOME SHOWERS ARE NOT COMPLETELY OUT  
OF THE QUESTION NEAR THE END OF THE PERIOD.  
 
FOR NOW HAVE KEPT THE FORECAST DRY PER THE NBM PPI AND POP WITH  
NO MORE THAN 10 PERCENT TO END THE PERIOD, WHILE HIGHER PPI AND  
POPS SOUTH OF THE AREA NEARER TO THE CREST OF THE APPALACHIANS.  
THE NBM TEMPERATURES WERE GENERALLY MIDDLE OF THE ROAD AMONG THE  
GUIDANCE SO NO CHANGES WERE MADE TO HIGH TEMPERATURES. A BIT OF A  
RIDGE/VALLEY SPLIT WAS INCLUDED FOR WEDNESDAY NIGHT LOWS, THOUGH  
IF A SOLUTION NEARER TO THE ECMWF OR ENS MEAN WERE TO VERIFY CLOUD  
COVER WOULD LIKELY PRECLUDE SUCH A SPLIT OVER MOST OF IF NOT ALL  
OF EASTERN KY.  
 

 
   
AVIATION
 
(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)  
ISSUED AT 214 AM EDT FRI SEP 12 2025  
 
VFR WAS OBSERVED AT THE TAF SITES AT ISSUANCE TIME WITH VALLEY FOG  
EVIDENT IN PORTIONS OF THE KY, BIG SANDY, AND CUMBERLAND BASIN  
PER SATELLITE IMAGERY. SOME MVFR VIS REDUCTIONS WERE REPORTED AT  
NON TAF LOCATIONS, KI35 AND KBYL WITH LOW STRATUS LEADING TO VLIFR  
AT KI35 AND BASED ON KY MESONET CAMERAS MVFR OR LOWER IS OCCURRING  
IN SEVERAL VALLEY LOCATIONS. WITH SOME LIGHT RAIN HAVING FALLEN  
NEAR THE KLOZ AREA AND GUIDANCE CONTINUING TO FORECAST REDUCTIONS  
TO MVFR AT KSME AS WELL, OPTED TO CONTINUE WITH A TEMPO FOR BOTH  
KLOZ AND KSME NEARER TO 12Z. HOWEVER, BASED ON THE GUIDANCE  
TRENDS, OPTED TO GO WITH MVFR REDUCTIONS VERSUS IFR WITHIN THE  
TEMPO. OTHERWISE, VALLEY FOG SHOULD LIFT AND DISSIPATE DURING THE  
12Z TO 14Z TIMEFRAME, GIVING WAY TO VFR FOR THE REST OF THE  
PERIOD, ALTHOUGH REDUCTIONS TO FOG IN VALLEY AREAS ARE ANTICIPATED  
AGAIN AFTER ABOUT 03Z TO END THE PERIOD. WITH SURFACE AND UPPER  
LEVEL HIGH PRESSURE DOMINATING, WINDS WILL REMAIN LIGHT AND  
VARIABLE.  
 

 
   
JKL WATCHES/WARNINGS/ADVISORIES
 
 
NONE.  
 

 
 

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