954  
FXUS63 KJKL 120545 AAA  
AFDJKL  
 
AREA FORECAST DISCUSSION...UPDATED  
NATIONAL WEATHER SERVICE JACKSON KY  
1245 AM EST TUE NOV 12 2024  
   
KEY MESSAGES  
 
 
- A COLD FRONT WILL INCREASE CHANCES FOR RAIN FROM WEDNESDAY NIGHT  
TO THURSDAY EVENING.  
 
- TEMPERATURES WILL BE BE A FEW DEGREES BELOW NORMAL TUESDAY  
THROUGH FRIDAY, WITH THE EXCEPTION OF WEDNESDAY.  
 
 
   
UPDATE  
 
ISSUED AT 1230 AM EST TUE NOV 12 2024  
 
NO SIGNIFICANT CHANGES TO THE FORECAST WITH JUST THE INCLUSION OF  
THE LATEST OBS AND TRENDS FOR THE T/TD/SKY GRIDS FOR THE UPDATE.  
THESE MINOR ADJUSTMENTS HAVE BEEN SENT TO THE NDFD AND WEB SERVERS  
ALONG WITH A FRESHENING OF THE ZONES AND SAFS.  
 
UPDATE ISSUED AT 1007 PM EST MON NOV 11 2024  
 
NOT MANY CHANGES MADE TO THE GRIDS AS THEY'VE BEEN LARGELY ON  
TRACK. JUST A FEW TOUCH-UPS BASED ON THE LATEST SURFACE  
OBSERVATIONS AND UPDATES TO SKY GRIDS BASED ON LATEST SATELLITE  
IMAGERY. LASTLY, UPDATED EVENING TEXT AND RADIO PRODUCTS BASED ON  
THE CHANGES. GRIDS HAVE BEEN SAVED AND SENT.  
 
 
   
SHORT TERM  
(THIS EVENING THROUGH TUESDAY NIGHT)  
ISSUED AT 413 PM EST MON NOV 11 2024  
 
LATE THIS AFTERNOON AT THE AXIS OF N UPPER LEVEL TROUGH EXTENDED  
FROM THE HUDSON BAY REGION TO THE NORTHEASTERN CONUS TO THE  
CAROLINAS. A SHORTWAVE TROUGH/UPPER LOW MOVING THROUGH THE UPPER  
LEVEL TROUGH WAS OVER THE LOWER ST LAWRENCE VALLEY HEADED TO THE  
MARITIMES WHILE ANOTHER SHORTWAVE TROUGH/UPPER LOW WAS WORKING  
INTO THE EASTERN GREAT LAKES. AN UPPER LEVEL RIDGE WAS CENTERED  
FROM MEXICO INTO THE WESTERN GULF OF MEXICO WITH RIDGING NORTH  
THROUGH TX TO THE DAKOTAS WHILE A TROUGH WAS WORKING INTO THE  
WESTERN CONUS. AT THE SURFACE, THE FRONT THAT CROSSES THE REGION  
LAST NIGHT INTO THIS MORNING WAS WORKING ACROSS THE APPALACHIANS  
WITH A RIDGE OF HIGH PRESSURE HAVING NOSED INTO THE LOWER OH  
VALLEY FROM THE SOUTHERN PLAINS. ANOTHER SFC LOW WAS MOVING FROM  
ONTARIO INTO QUEBEC WITH THE ASSOCIATED COLD FRONT NEARING THE  
LOWER OH VALLEY FROM THE MID MS VALLEY. A SFC RIDGE HIGH PRESSURE  
WAS IN PLACE FROM MANITOBA AND WESTERN ONTARIO INTO THE DAKOTAS  
AND UPPER MS VALLEY. DRIER AIR HAS MOVED INTO EASTERN KY BEHIND  
THE FIRST COLD FRONT WITH CURRENT DEWPOINTS GENERALLY RANGING  
THROUGH THE 40S THOUGH AFTERNOON MIXED DEWPOINTS IN SOME CASES  
WERE IN THE UPPER 30S.  
 
TONIGHT AND TUESDAY, THE SHORTWAVE TROUGH NEARING THE EASTERN  
GREAT LAKES AT PRESENT WILL ROTATE INTO THE NORTHEAST AND THEN TO  
THE MARITIMES TO WESTERN ATLANTIC WITH THE AXIS OF THE MEAN UPPER  
LEVEL TROUGH ALSO WORKING WELL EAST OF EASTERN KY. MEANWHILE, THE  
UPPER LEVEL RIDGE TO THE WEST WILL WORK EAST ACROSS THE PLAINS  
AND BUILD INTO THE MS VALLEY AND THEN TO THE WESTERN GREAT LAKES  
TO THE LOWER OH VALLEY TO THE GULF OF MEXICO. TO THE WEST, AN  
UPPER LEVEL TROUGH WILL WORK DEEPER INTO THE WESTERN CONUS AND  
THEN TO THE ROCKIES. TUESDAY NIGHT, THE AXIS OF THE UPPER LEVEL  
RIDGE WILL SHIFT TO A JAMES BAY TO EASTERN GREAT LAKES TO  
SOUTHERN APPALACHIANS TO EASTERN GULF OF MEXICO LINE. AT THE  
SURFACE, THE UPSTREAM COLD FRONT WILL DROP TO NEAR THE OH RIVER  
DURING THE EARLY TO MIDDLE PART OF THE EVENING AND INTO EASTERN  
KY LATE IN THE EVENING INTO THE OVERNIGHT HOURS. THIS BOUNDARY  
SHOULD SAG SOUTH OF EASTERN KY BY DAWN AS SFC HIGH PRESSURE  
BUILDING EAST ACROSS ONTARIO AND INTO THE GREAT LAKES AND INTO THE  
LOWER TO MIDDLE OH VALLEY AND EASTERN KY. THIS BOUNDARY WILL  
BECOME MORE DIFFUSE ON TUESDAY AS IT SAGS FURTHER SOUTH AS HIGH  
PRESSURE AT THE SURFACE AND ALOFT DOMINATES WITH RISING HEIGHTS  
EXPECTED AT 500 MB. HIGH PRESSURE AT THE SURFACE AND ALOFT WILL  
CONTINUE TO DOMINATE ON TUESDAY NIGHT AS WELL AS BOTH SHIFT EAST.  
BEHIND THE BOUNDARY TONIGHT, PW IS PROGGED TO FALL TO THE 0.2 TO  
0.3 INCH RANGE IF NOT SLIGHTLY LOWER, OR CLIMATOLOGICALLY BELOW  
THE 10TH PERCENTILE FOR THIS TIME OF YEAR, WITH ONLY A MODEST  
INCREASE IN PW TO ABOUT 0.2 TO 0.4 BY LATE TUESDAY NIGHT. 850 MB  
TEMPERATURE, ESPECIALLY IN THE NORTH AND EAST WILL BE A COUPLE OF  
DEGREES COLDER ON AVERAGE COMPARED TO TODAY.  
 
THE COLD FRONT TONIGHT MAY BRING A BIT OF AN INCREASE IN MIXINESS  
AS IT PASSES SO THE TIMING AND INTENSITY OF FOG FORMATION IN  
DEEPER VALLEYS IS UNCERTAIN. IN ADDITION, THERE WILL BE A BIT OF  
INCREASE IN MOISTURE GENERALLY BELOW 850 MB AS THE FRONT PASSES SO  
A FEW TO SCATTERED LOW TO MID LEVEL CLOUDS CANNOT BE RULED OUT.  
OTHERWISE, ANY LINGERING CLOUDS AND VALLEY FOG SHOULD LIFT AND  
MIX ON TUESDAY MORNING AND GIVE WAY TO MOSTLY SUNNY TO SUNNY  
SKIES. UNDER HIGH PRESSURE SHIFTING EASTWARD AND A TREND TO  
SOUTHERLY GRADIENT/FLOW FOR RIDGES, A MODERATE RIDGE/VALLEY SPLIT  
IS EXPECTED FOR TUESDAY NIGHT. SOME DEEPER VALLEY FOG MAY AGAIN  
FORM, ESPECIALLY SOUTH OF THE MOUNTAIN PARKWAY.  
   
LONG TERM  
(WEDNESDAY THROUGH MONDAY)  
ISSUED AT 335 PM EST MON NOV 11 2024  
 
MODEL SUITE SUGGESTS A HIGH AMPLITUDE, PROGRESSIVE PATTERN ALOFT  
THROUGH THE EXTENDED WITH THE CORE OF THE WESTERLIES, OR MAIN  
CORRIDOR OF STRONGEST STEERING WINDS GENERALLY ESTABLISHED ACROSS  
THE HEART OF THE CONUS. WE START THE EXTENDED WITH RIDGING ALOFT  
OVER THE OHIO VALLEY, WITH A TROUGH OVER THE GREAT PLAINS. UNLIKE  
PREVIOUS STORM SYSTEMS OF LATE, THIS TROUGH HAS NO ISSUES WITH THE  
RIDGE OVER THE EAST, AND MOVES EASTWARD WITH EAST INTO THE MIDWEST  
AND OHIO VALLEY. THIS TROUGH PUSHES ACROSS OUR REGION AT A FAST  
CLIP, WITH THE AXIS PASSING EAST OF OUR AREA BY THE END OF THE DAY  
THURSDAY. RIDGING BUILDS BACK OVER THE OHIO VALLEY AND REMAINS THERE  
UNTIL A SHORTWAVE TROUGH SLIDES SOUTHEAST ACROSS THE GREAT LAKES AND  
INTO THE OHIO VALLEY BY THE END OF THE FORECAST WINDOW. AT THE  
SURFACE, A COLD FRONT PASSES THROUGH EASTERN KENTUCKY DURING THE DAY  
THURSDAY, CLEARING THE AREA BY THURSDAY EVENING. THIS FRONT IS QUITE  
POTENT AND FORMS OVER THE PLAINS BY THE START OF THE PERIOD, THEN IN  
QUICK FASHION REACHES OUR FORECAST AREA IN LESS THAN 36 HOURS. HIGH  
PRESSURE THEN TRANSITS THE OHIO VALLEY UNTIL THE END OF THE PERIOD,  
WHEN ANOTHER COLD FRONT MANAGES TO DROP SOUTHEASTWARD FROM THE UPPER  
MIDWEST AND INTO THE COMMONWEALTH. THE REMAINDER OF THE LONG TERM  
DISCUSSION WILL FOCUS ON THE MID-WEEK SYSTEM.  
 
SENSIBLE WEATHER FEATURES AN UPTICK IN ACTIVE WEATHER ACROSS THE  
REGION, MAINLY DUE TO THE POLAR JET DROPPING FURTHER SOUTH. THE  
REMNANTS OF A TROPICAL WAVE REMAINS OVER THE GULF OF MEXICO. AS  
THE SURFACE FRONT RACES EASTWARD WEDNESDAY INTO THURSDAY, A  
CONSIDERABLE AMOUNT OF MOISTURE IS DRAWN NORTHWARD FROM THE  
TROPICAL WAVE OVER THE GULF OF MEXICO. PWATS INCREASE RAPIDLY  
ACROSS THE TN VALLEY AND CLIMB TO BETWEEN 1 AND 1.3 INCHES AHEAD  
OF THE FRONT BY THE TIME IT ENTERS OUR AREA. A 50KT PLUS H850 JET  
STREAK NOSING ITS WAY INTO THE AREA WEDNESDAY NIGHT COMBINED WITH  
GOOD DIVERGENT FLOW ALOFT SHOULD HELP PRODUCE SOME GOOD LIFT IN  
THE COLUMN ABOVE THE REGION. ALL SAID THIS WILL HELP SET THE TABLE  
SYNOPTICALLY FOR FAVORABLY HIGH RAINFALL TOTALS. ONE LIMITING  
FACTOR WILL BE THE SPEED OF THE SYSTEM THROUGH OUR AREA. ENSEMBLE  
PROBABILISTIC DATA SUPPORTS THIS SCENARIO AS THE PROBABILITY OF  
GTE 0.5 INCHES OF RAINFALL ACROSS EASTERN KENTUCKY IS BETWEEN  
55-75%. PROBABILITIES OF GTE 0.25 INCHES IS BETWEEN 80 AND 90%. SO  
THIS NEXT SYSTEM COULD TURN OUT TO BE A SOLID WETTING RAIN, AND  
POSSIBLY SOAKING RAIN FOR THE ENTIRE AREA. OBVIOUSLY THERE ARE  
PORTIONS OF THE AREA THAT SORELY NEED THE RAINFALL.  
 
 
   
AVIATION  
(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)  
ISSUED AT 1245 AM EST TUE NOV 12 2024  
 
VFR CONDITIONS WILL PREVAIL ACROSS ALL TAF SITES THROUGH THE  
AVIATION FORECAST PERIOD. FOG IS LIKELY TO DEVELOP OVERNIGHT BUT  
WILL NOT FILTER INTO ANY OF THE TAF SITES. LASTLY, WINDS ARE  
FORECAST TO BE LIGHT AND VARIABLE WITH A SLIGHT IN BUMP IN  
NORTHEASTERLY WINDS TUESDAY AFTERNOON.  
 
 
   
JKL WATCHES/WARNINGS/ADVISORIES  
 
NONE.  
 
 
 
 
UPDATE...GREIF  
SHORT TERM...JP  
LONG TERM...RAY  
AVIATION...VORST/GREIF  
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