813  
FXUS63 KJKL 112331  
AFDJKL  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE JACKSON KY  
731 PM EDT MON MAY 11 2026  
   
KEY MESSAGES  
 
- ISOLATED INSTANCES OF FROST ARE POSSIBLE LATE TONIGHT INTO  
TUESDAY MORNING IN DEEPER RURAL VALLEYS AND HOLLOWS - MAINLY  
AWAY FROM MAINSTEM RIVERS.  
 
- THERE IS A GREATER CONCERN FOR FROST FORMATION LATE THURSDAY  
NIGHT INTO FRIDAY MORNING, ESPECIALLY IN SHELTERED RURAL VALLEYS  
AND HOLLOWS AWAY FROM MAINSTEM RIVERS.  
 
- A COLD FRONT IS EXPECTED TO BRING CHANCES FOR SHOWERS AND  
PERHAPS A FEW THUNDERSTORMS FOR WEDNESDAY.  
 
- ADDITIONAL SHOWER AND THUNDERSTORM CHANCES ARRIVE THIS WEEKEND  
ACCOMPANIED BY A TREND OF INCREASINGLY WARMER TEMPERATURES INTO  
EARLY NEXT WEEK.  
 
 
 
   
UPDATE  
 
ISSUED AT 731 PM EDT MON MAY 11 2026  
 
ADDED THE LATEST SURFACE OBSERVATIONS AND INTERPOLATED THROUGH THE  
REST OF THE EVENING. GRIDS HAVE BEEN SAVED AND SENT.  
 
 
   
SHORT TERM  
(THIS EVENING THROUGH TUESDAY NIGHT)  
ISSUED AT 228 PM EDT MON MAY 11 2026  
 
AN UPPER DISTURBANCE THAT BROUGHT WIDESPREAD RAIN TO SOUTHEASTERN  
KENTUCKY THIS MORNING WILL TRACK EAST OF THE AREA BY THIS EVENING,  
WITH NORTHWESTERLY CYCLONIC FLOW GRADUALLY BECOMING NEUTRAL BY  
TUESDAY MORNING, WEAKLY ANTICYCLONIC DURING THE DAY TUESDAY WITH  
PASSING SHORTWAVE RIDGING, AND THEN INCREASINGLY CYCLONIC AGAIN AS A  
DISTURBANCE AND SURFACE COLD FRONT APPROACH THE AREA FROM THE  
NORTHWEST TUESDAY NIGHT INTO WEDNESDAY MORNING.  
 
BELOW NORMAL LOW TEMPERATURES ARE EXPECTED TONIGHT UNDER CLEAR TO  
MOSTLY CLEAR SKIES AND LIGHT WINDS. GIVEN THIS MORNING'S RAINFALL  
COMBINED WITH GOOD RADIATIONAL COOLING CONDITIONS, EXPECT WIDESPREAD  
LOWS IN THE UPPER 30S TO MID 40S, WITH FOG IN MOST IF NOT ALL RIVER  
VALLEYS, WITH JUST THE SLIGHTEST CHANCE OF FROST IN SOME OF THE  
OUTLYING VALLEYS AND HOLLOWS.  
 
WITH SHORTWAVE RIDGING AND JUST A BIT OF LOW-LEVEL WARM ADVECTION  
TUESDAY, HIGHS WILL CLIMB TO NEAR NORMAL FOR THIS TIME OF THE  
YEAR IN THE MID- 70S UNDER MOSTLY CLEAR SKIES.  
 
WARM ADVECTION SLOWLY INCREASES THROUGH THE TUESDAY NIGHT PERIOD,  
AND CHANCE POPS ARE INTRODUCED FROM THE NORTHWEST TOWARD MORNING AS  
A COLD FRONT MOVES TOWARD THE AREA. GIVEN VERY LIMITED INSTABILITY  
INDICATED IN THE MODELS, ANY ACTIVITY ARRIVING BEFORE 12Z WEDNESDAY  
WOULD BE IN THE FORM OF SHOWERS. BEFORE THE ARRIVAL OF CLOUDS AND  
POTENTIAL SHOWERS, GOOD RADIATIONAL COOLING DURING THE FIRST HALF OF  
THE OVERNIGHT, DESPITE INCREASING WARM ADVECTION, WOULD SUPPORT A  
FAIRLY ROBUST RIDGE-VALLEY SPLITS IN TEMPERATURES AS WELL AS THE  
LIKELY FORMATION OF FOG IN THE MORE PROTECTED RIVER VALLEYS.  
   
LONG TERM  
(WEDNESDAY THROUGH MONDAY)  
ISSUED AT 339 PM EDT MON MAY 11 2026  
 
THE LONG-TERM PERIOD BEGINS DAYBREAK WEDNESDAY WITH THE NEXT ROUND OF  
UNSETTLED WEATHER DEVELOPING FROM THE NORTHWEST WITH AN APPROACHING  
COLD FRONT. ALOFT, A POTENT HIGH AMPLITUDE 500 HPA TROUGH AXIS WILL  
EXTEND FROM NORTHERN ONTARIO SOUTHWARD ACROSS THE OHIO AND TENNESSEE  
VALLEYS. MEANWHILE, A SIMILARLY HIGH AMPLITUDE RIDGE EXTENDS FROM NEW  
MEXICO NNW ALONG THE ROCKY MOUNTAINS ALL THE WAY TO OVER THE BROOKS  
RANGE OF ALASKA. IN BETWEEN THIS UNUSUALLY STRONG UPPER LEVEL  
RIDGE AND TROUGH, SURFACE HIGH PRESSURE RESIDES FROM THE PLAINS  
NORTH AND WESTWARD INTO THE CANADIAN ARCTIC.  
 
THE AFOREMENTIONED COLD FRONT SEEMS TO BE MOVING THROUGH MORE QUICKLY  
IN RECENT GUIDANCE AND SHOULD INITIALLY BE ON OUR NORTHWESTERN  
DOORSTEP MID-MORNING ON WEDNESDAY BEFORE QUICKLY MARCHING SOUTHEAST  
ACROSS THE FORECAST AREA AND DEPARTING INTO SOUTHWESTERN VIRGINIA BY  
EARLY TO MID-AFTERNOON. THE EARLY TIMING OF THE FRONTAL PASSAGE WILL  
LIMIT DESTABILIZATION AND OVERALL THUNDERSTORM POTENTIAL, ESPECIALLY  
ACROSS THE NORTHWESTERN HALF OF THE CWA. OVER THE SOUTHEASTERN HALF  
OF THE CWA, THE LATE MORNING AND EARLY AFTERNOON FRONTAL ARRIVAL MAY  
GIVE SUFFICIENT TIME FOR MORE SUBSTANTIAL DESTABILIZATION (MLCAPE  
MIGHT REACH 500 TO 1000 J/KG). IF SUFFICIENT DESTABILIZATION OCCURS,  
EFFECTIVE SHEAR SHOULD BE GREATER THAN 30 KTS AND COULD FAVOR  
SOME ORGANIZATION OF THE CELLS. HOWEVER, THE RECENT FORECAST  
TRENDS FOR A QUICKER FRONTAL PASSAGE LEAVE SOME DOUBT ON THIS  
POTENTIAL. OVERALL POPS FOR THE FRONTAL PASSAGE ARE HIGHEST OVER  
THE BIG SANDY BASIN WHERE 80 TO 90 PERCENT PROBABILITIES OF  
MEASURABLE RAINFALL ARE COMMON, BUT THOSE QUICKLY DECREASE WITH  
SOUTHWESTWARD EXTENT, ONLY RANGING IN TO THE 10 TO 30 PERCENT  
PROBABILITY RANGE IN THE DROUGHT-STRICKEN AREAS AROUND LAKE  
CUMBERLAND. RAINFALL AMOUNTS GENERALLY APPEAR LIGHT, MAINLY UNDER  
0.10 INCH OUTSIDE OF THUNDERSTORMS. ALSO, 850 HPA TEMPERATURES  
NEAR 10C AND GOOD MIXING SHOULD SUPPORT TEMPERATURES ON WEDNESDAY  
AT SIMILAR LEVELS COMPARED TO TUESDAY, RANGING IN THE 70S.  
 
LOW-LEVEL CAA BEHIND THE FRONT WILL SEND 850 HPA TEMPERATURES FALLING  
LATER IN THE DAY ON WEDNESDAY AND THROUGHOUT WEDNESDAY NIGHT. THE  
11/00Z LREF MEAN SUPPORTED 850 HPA TEMPERATURES FALLING TO 2 TO 4C BY  
12Z THURSDAY, WITH THE COLDER END OF THE GUIDANCE SUITE NEAR 0C. THE  
NORTHWESTERLY FLOW THROUGH WEDNESDAY NIGHT DOES DIMINISH FROM 20  
TO 25 KTS AT 925 HPA IN THE EVENING TO 10 TO 20 KTS BY DAYBREAK,  
BUT SHOULD KEEP LOW-LEVEL MIXING GOING FOR MOST OF THE NIGHT AND  
THUS KEEP TEMPERATURES FROM RADIATING VERY EFFICIENTLY. THUS,  
ANTICIPATE WIDESPREAD LOWS IN THE 40S EARLY THURSDAY MORNING. A  
DRY, COOL CANADIAN AIR MASS WILL THEN RESIDE OVER THE COMMONWEALTH  
FOR THURSDAY WITH MINIMAL CHANGE IN THE OVERALL AIR MASS TEMPERATURE.  
GIVEN THE 00Z LREF MEAN 850 HPA TEMPERATURES OF 3 TO 5C, WIDESPREAD  
HIGHS IN THE LOWER TO MIDDLE 60S SEEMS REASONABLE FOR THURSDAY  
AFTERNOON GIVEN DEEP MIXING, BUT IF THE ACTUAL AIR MASS IS CLOSER  
TO THE COLDER END OF GUIDANCE, THEN MANY PLACES COULD STRUGGLE TO  
REACH 60F. GIVEN THE SPREAD IN THE GUIDANCE SUITE REGARDING THE  
TRUE DRYNESS AND MODIFICATION OF THIS AIR MASS, THERE IS CURRENTLY  
MODERATE CONFIDENCE IN THURSDAY'S HIGH TEMPERATURES.  
 
THIS WILL ALL BE IN PLACE AS HIGH PRESSURE SHIFTS EAST AND CRESTS  
DIRECTLY OVER EASTERN KENTUCKY THURSDAY NIGHT, PROVIDING NEARLY  
OPTIMAL CONDITIONS FOR RADIATIVE COOLING. IF DEW POINTS REMAIN MAINLY  
ABOVE 32F ON THURSDAY AFTERNOON, THERE WILL LIKELY BE A COMPETITION  
BETWEEN FOG AND FROST THURSDAY NIGHT, ESPECIALLY IN THE SHELTERED  
VALLEYS AND HOLLOWS. THOSE LOCALES PRONE TO FOG ALONG THE MAINSTEM  
RIVERS AND LARGER TRIBUTARIES ARE LIKELY TO FOG, WHEREAS THOSE  
HOLLOWS AND RURAL VALLEY/LOW-LYING AREAS NOT PRONE TO FOG ARE  
MORE LIKELY TO PICK UP ON A LATE SEASON FROST. COOP MOS SUGGESTS  
LOWS IN THE MID 30S BY EARLY FRIDAY MORNING FOR THE COOLER HOLLOWS  
AND VALLEYS AND IN THE UPPER 30S IN THOSE LOCATIONS PRONE TO FOG.  
THOSE WITH COLD-SENSITIVE AGRICULTURAL INTERESTS ARE ENCOURAGED  
TO MONITOR LATER FORECASTS FOR THE LATE THURSDAY NIGHT AND EARLY  
FRIDAY MORNING TIMEFRAME, AS A FROST ADVISORY MAY EVENTUALLY BE  
NEEDED FOR SOME OF OUR SHELTERED EASTERN VALLEYS. FOR PERSPECTIVE,  
THE 30-YEAR NORMAL LOWS (1991-2020 COMPUTATIONAL PERIOD) FOR MAY  
15TH RANGE FROM 49F IN THE COLDER NORTHEASTERN HOLLOWS TO 56F IN  
THE VICINITY OF LAKE CUMBERLAND, WHILE DAYTIME HIGHS RANGE FROM  
74F TO 76F ACROSS THE LOWER ELEVATIONS. FURTHERMORE, THE AVERAGE  
LAST FROST DATES (TEMPERATURES 36F OR LESS) FOR THE COLDER  
NORTHEASTERN HOLLOWS GENERALLY FALL IN THE MAY 5TH TO MAY 18TH  
TIMEFRAME.  
 
FOR THE COLDER HOLLOWS, THIS COULD BE THE LATEST FROST IN 5 TO 10  
YEARS. MOST OF THE MAINSTEM RIVER VALLEYS SHOULD FOG AND BE  
PROTECTED FROM FROST CONCERNS. AFTER THIS COLD NIGHT, MAY 15TH  
WILL MARK THE PIVOT TO A SIGNIFICANT PATTERN CHANGE HEADING INTO  
LATE MAY. HEIGHTS ALOFT WILL RAPIDLY REBOUND AS THE UPPER LEVEL  
RIDGING PRESSES EASTWARD, REPLACING THE TROUGHING, THOUGH THE  
RIDGE WILL BE FLATTENED BY A PACIFIC TROUGH THAT RIDES ALONG THE  
US AND CANADIAN BORDER LATE WEEK. LOCALLY, A MILD SOUTHWESTERLY  
RETURN FLOW DEVELOPS BEHIND THE DEPARTING SURFACE HIGH WHILE A  
COLD FRONT ASSOCIATED WITH THE PACIFIC TROUGH APPROACHES THE OHIO  
VALLEY. HOWEVER, THAT FRONT WILL LOSE ITS UPPER LEVEL FORCING AS A  
NEW UPSTREAM TROUGH DIGS DEEPLY INTO THE WESTERN CONUS LATE WEEK  
AND EARLY NEXT WEEK. SPECIFIC DETAILS ON THE OVERALL RAINFALL  
THREAT WITH THE APPROACHING FRONT REMAIN OBSCURE DUE TO INCREASED  
MODEL SPREAD, BUT AGREEMENT IS GOOD THAT RISING HEIGHTS AND VERY  
WARM TEMPERATURES ALOFT WILL SEND THERMOMETERS SOARING PAST NORMAL  
LEVELS BY SATURDAY AND POTENTIALLY NEARING RECORD HIGHS (CLOSE TO  
90F) BY MONDAY.  
 
FOR AREA GARDENERS, THE OUTLOOK FOR THE REMAINDER OF THE MONTH,  
ONCE WE GET PAST FRIDAY MORNING'S CHILL, DOES NOT FAVOR ANY  
ADDITIONAL COLD SNAPS SUFFICIENTLY COOL FOR FROST, EVEN IN THE  
COLDER SHELTERED HOLLOWS. HOWEVER, A FEW COLD FRONTS COULD STILL  
BRING COOL MORNINGS (PROBABLY 40S TO NEAR 50F).  
 
 
   
AVIATION  
(FOR THE 00Z TAFS THROUGH 00Z TUESDAY EVENING)  
ISSUED AT 731 PM EDT MON MAY 11 2026  
 
VFR CONDITIONS ARE EXPECTED TO PREVAIL THROUGH THE TAF PERIOD FOR  
KJKL, KSJS, KSYM AND KIOB BUT MVFR TO IFR CONDITIONS ARE POSSIBLE  
AS RIVER VALLEY FOG IS FORECAST TO DEVELOP AND IMPACT KLOZ AND  
KSME. ONCE THE FOG BURNS OFF, ALL SITES WILL RETURN TO VFR AND  
STAY THERE. LIGHT AND VARIABLE WINDS ARE LIKELY THROUGH THE TAF  
WINDOW.  
 
 
   
JKL WATCHES/WARNINGS/ADVISORIES  
 
NONE.  
 
 
 
 
 
UPDATE...VORST  
SHORT TERM...CMC  
LONG TERM...GEERTSON  
AVIATION...VORST  
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