667  
FXUS63 KJKL 222042  
AFDJKL  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE JACKSON KY  
342 PM EST WED JAN 22 2020  
   
SHORT TERM
 
(THIS EVENING THROUGH THURSDAY NIGHT)  
ISSUED AT 315 PM EST WED JAN 22 2020  
 
HIGH PRESSURE AND UPPER LEVEL RIDGING ARE SOLIDLY IN CONTROL TODAY.  
HOWEVER, AS THIS SYSTEM BEGINS TO SHIFT EASTWARD OVERNIGHT, RETURN  
SOUTHERLY FLOW WILL TAKE HOLD, ADVECTING MOISTURE INTO THE REGION.  
MEANWHILE, A LONGWAVE TROUGH WILL BE LOCATED ACROSS THE CENTRAL  
PLAINS WITH TWO SURFACE LOW PRESSURE SYSTEMS IMPACTING THE CENTRAL  
PLAINS AND SOUTHERN PLAINS/GULF COAST. PRECIP IS CURRENTLY ONGOING  
ACROSS THE CENTRAL CONUS IN RESPONSE TO THESE SYSTEMS. AS THIS  
LONGWAVE TROUGH AND SURFACE SYSTEMS CONTINUE TO TRACK EASTWARD  
THROUGHOUT THE OVERNIGHT AND INTO THE DAY THURSDAY, PRECIP WILL ALSO  
SHIFT EASTWARD AND BEGIN TO MAKE ITS WAY ACROSS KENTUCKY. BY 0Z  
FRIDAY, AS WE TRANSITION TO THE EXTENDED PORTION OF THE FORECAST,  
A CLOSED UPPER LEVEL LOW WILL HAVE DEVELOPED IN THE SOUTH/CENTRAL  
PLAINS, AND THE TWO SURFACE LOWS WILL BEGIN MERGING AS THEY REACH  
THE LOWER AND MID-MISSISSIPPI VALLEY.  
 
THERE IS GOOD AGREEMENT BETWEEN THE CAMS THAT PRECIP ASSOCIATED WITH  
THIS SYSTEM WILL BEGIN MOVING INTO THE CWA DURING THE AFTERNOON  
THURSDAY, EXPANDING ACROSS THE CWA THROUGHOUT THE EVENING AND  
OVERNIGHT. GIVEN THE CONTINUED WARM AIR ADVECTION LEADING UP TO  
THE ONSET OF THIS SYSTEM, AND THE LOW'S LOCATION TO OUR W AND SW,  
TEMPS ACROSS THE AREA SHOULD BE WARM ENOUGH BOTH THURSDAY AND  
THURSDAY NIGHT TO SUPPORT LIQUID PRECIP. HIGHS ON THURSDAY WILL BE  
IN THE UPPER 40S TO AROUND 50. LOWS THURSDAY NIGHT WILL BE IN THE  
UPPER 30S AS THE RAIN INTENSIFIES.  
   
LONG TERM
 
(FRIDAY THROUGH WEDNESDAY)  
ISSUED AT 342 PM EST WED JAN 22 2020  
 
THE EXTENDED WILL START OFF VERY WET AS A COLD FRONT WILL BE  
WORKING EAST ACROSS THE AREA ON FRIDAY. PLENTY OF MOISTURE AND  
LIFT AHEAD OF THE BOUNDARY WILL PROVIDE WIDESPREAD RAIN THROUGH  
EARLY AFTERNOON. A DRY SLOT WILL OVERTAKE THE AREA INTO FRIDAY  
EVENING, BUT SOME REDEVELOPMENT IS POSSIBLE WITHIN THIS DRY SLOT  
AS A WEAK RIBBON OF INSTABILITY PUSHES NORTHEAST ACROSS THE AREA.  
WOULDN'T COMPLETELY RULE OUT A ISOLATED THUNDERSTORM, BUT LOTS OF  
UNCERTAINTY WITH HOW FAR NORTH THIS THREAT WILL EXTEND, SO WILL  
LEAVE IT OUT FOR NOW. COLDER AIR WILL FILTER INTO THE AREA FRIDAY  
NIGHT. SOME WRAP AROUND MOISTURE WILL SLIDE ACROSS THE AREA AS THE  
LOW TO OUR NORTHEAST STARTS TO PIVOT NORTHEASTWARD AWAY FROM THE  
AREA. THIS COULD PROVIDE SOME LIGHT RAIN AND/OR SNOW SHOWERS ON  
SATURDAY. NORTHWEST FLOW, COMBINED WITH A FEW EMBEDDED WAVES WILL  
LIKELY PRODUCE A PROLONGED PERIOD OF LIGHT RAIN AND SNOW SHOWERS  
THROUGH SUNDAY, AND MAYBE EVEN SUNDAY NIGHT. SATURDAY NIGHT MAY  
BE OUR BEST OPPORTUNITY FOR SOME LIGHT COATINGS OF SNOW AS  
TEMPERATURES COOL OFF BELOW FREEZING, ESPECIALLY IN THE HIGHER  
TERRAIN. GIVEN THE UNCERTAINTY ON SNOW ACCUMULATION POTENTIAL,  
WILL HOLD OFF ON ANY MENTION IN THE HWO FOR RIGHT NOW. HIGH  
PRESSURE MAY FINALLY ARRIVE BY MONDAY WITH CLOUDS ON THE DECREASE.  
SHOULD SEE TEMPERATURES MODERATE THROUGH THE FIRST PORTION OF  
NEXT WEEK, BEFORE OUR NEXT STORM SYSTEM EMERGES LATE WEDNESDAY,  
PRODUCING OUR NEXT CHANCE FOR RAIN.  
 

 
   
AVIATION
 
(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON)  
ISSUED AT 104 PM EST WED JAN 22 2020  
 
A CENTER OF SURFACE HIGH PRESSURE AND AN UPPER LEVEL RIDGE AXIS  
ARE CURRENTLY IN PLACE ACROSS EASTERN KENTUCKY. THIS WILL SLOWLY  
SHIFT EASTWARD THROUGHOUT THE TAF PERIOD, BUT SHOULD RETAIN ITS  
INFLUENCE ACROSS EASTERN KENTUCKY. VFR CONDITIONS ARE EXPECTED AS  
A RESULT. PASSING CIRRUS WILL CONTINUE INTO THE AFTERNOON, WITH  
CIGS FORECAST TO THICKEN AND SLOWLY LOWER HEADING INTO THE  
OVERNIGHT AND THEN INTO THURSDAY AHEAD OF OUR NEXT APPROACHING  
WEATHER SYSTEM. SOME MID-LEVEL CLOUDS MAY BEGIN TO MOVE IN FROM  
THE WEST AS WE ROUND OUT THE LAST COUPLE HOURS OF THE TAF PERIOD.  
WINDS WILL ALSO CONTINUE TO BE LIGHT AND VARIABLE, GENERALLY  
UNDER 5KTS THROUGH THE PERIOD.  
 

 
   
JKL WATCHES/WARNINGS/ADVISORIES
 
 
NONE.  

 
 

 
 
SHORT TERM...JMW  
LONG TERM...KAS  
AVIATION...JMW  
 
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