864  
FXUS63 KLMK 161947  
AFDLMK  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE LOUISVILLE KY  
347 PM EDT TUE JUL 16 2019  
   
SHORT TERM
 
(THIS EVENING THROUGH WEDNESDAY)  
UPDATED AT 330 PM EDT TUE JUL 16 2019  
 
AFTERNOON SATELLITE IMAGERY REVEALS MOSTLY SUNNY SKIES ACROSS MUCH  
OF CENTRAL AND EASTERN KY. CLOUD COVER HAS REALLY BEEN LIMITED TO  
OUR FAR WESTERN COUNTIES WHERE SCATTERED CONVECTION HAS BEEN MOVING  
NORTHEASTWARD. TEMPERATURES RANGED FROM THE UPPER 80S IN THE SUN  
WITH 90-91 IN THE URBAN HEAT ISLANDS, TO THE UPPER 70S UNDER THE  
CLOUDS IN WESTERN KY.  
 
FOR THE REST OF THE AFTERNOON AND EVENING, WE WILL BE WATCHING THE  
REMNANTS OF TROPICAL CYCLONE BARRY MOVE NORTHEASTWARD THROUGH THE  
REGION. OVERALL CONVECTION LOOKS TO COME IN SEVERAL WAVES THIS  
AFTERNOON. FIRST WAVE IS PUSHING THROUGH SOUTHERN IN AT THE MOMENT.  
SECONDARY WAVE IS DEVELOPING FROM NEAR EVANSVILLE, IN SOUTHWARD INTO  
WESTERN TN. ATMOSPHERE IS MODESTLY UNSTABLE WITH MLCAPE VALUES IN  
THE 1200-1500 J/KG RANGE. THERE IS A POCKET OF ELEVATED EFFECTIVE  
SRH STRETCHING FROM OWENSBORO NORTHEASTWARD INTO OUR FAR NW CWA.  
OVERALL SURFACE FLOW REMAINS RATHER UNIDIRECTIONAL WITH SOME SPEED  
SHEER, BUT NOT REALLY SEEING MUCH IN THE WAY OF LOW-LEVEL BACKED  
FLOW. THE COMBO OF MLCAPE AND EFFECT SRH MAY POSE AN ISOLATED  
TORNADO RISK OVER OUR FAR NW CWA OVER THE NEXT FEW HOURS. HOWEVER,  
KLVX/KVWX VROT VALUES HAVE BEEN VERY LOW (20-25KT) AND LCL HEIGHTS  
ARE STILL AROUND 800-1000M. THUS, PROBABLY GOING TO SEE SEVERAL  
REPORTS OF FUNNEL CLOUDS WITH THE STRONGEST STORMS.  
 
PWAT GRADIENT WAS ALSO SEEN ACROSS THE REGION WITH VALUES AROUND 1.5-  
1.7IN ACROSS THE BLUEGRASS REGION AND THEN SHARPLY RISING TO ABOVE 2  
INCHES WEST OF EVANSVILLE. SO STORMS OUT WEST OF I-65 WILL BE  
CAPABLE OF PRODUCING HEAVY RAINFALL. FLASH FLOOD RISK IS CERTAINLY  
THERE, ESPECIALLY WHERE STORMS TRANSVERSE OVER THE SAME LOCATIONS  
REPEATEDLY OR TRAIN OVER THE SAME SWATH OF LAND.  
 
CONVECTIVE COVERAGE SHOULD SPREAD EASTWARD INTO THE I-65 CORRIDOR  
LATER THIS AFTERNOON AND INTO THE EVENING HOURS. JUST HOW FAR EAST  
WE'LL SEE IT GET IS RATHER QUESTIONABLE. MUCH OF THE HIGH  
RESOLUTION GUIDANCE KEEPS BEST CHANCES OF PRECIPITATION WEST OF A  
LINE FROM ABOUT FRANKFORT TO TOMPKINSVILLE. WITH THAT SAID, WILL  
KEEP HIGH POPS OUT WEST OF I-65 AND TAPERING IT TO CHANCE POPS OUT  
EAST.  
 
MOVING INTO THE OVERNIGHT HOURS, CONVECTION IS LIKELY TO DIMINISH IN  
COVERAGE AND INTENSITY WITH THE LOSS OF HEATING. WE'LL PROBABLY SEE  
SOME SCATTERED SHOWERS AND POSSIBLY A STORM OVERNIGHT, THOUGH THE  
BEST COMBO OF MOISTURE/INSTABILITY LOOKS TO REMAIN TO OUR SOUTH.  
WILL MAINTAIN CHANCE POPS OVERNIGHT, BUT WILL MONITOR TRENDS THIS  
EVENING AND MAKE FURTHER MODIFICATIONS AS NEEDED. LOWS WILL REMAIN  
MILD WITH READINGS IN THE 70S.  
 
FOR WEDNESDAY, UPPER TROUGH AXIS WILL SHIFT TO THE EAST ALONG WITH  
THE SLUG OF TROPICAL MOISTURE ASSOCIATED WITH THE REMNANTS OF BARRY.  
BEST CHANCES OF STORMS ON WEDNESDAY WILL LIKELY BE ACROSS THE  
NORTHEAST HALF OF THE FORECAST AREA. HIGHS WILL BE IN THE MID-UPPER  
80S IN MOST AREAS WITH A FEW SPOTS HITTING 90 ONCE AGAIN.  
 
QPF AMOUNTS THROUGH THE SHORT TERM PERIOD WILL LIKELY SEE BASIN  
AVERAGES AROUND AN INCH, THOUGH SOME ISOLATED AMOUNTS OF 2-3 INCHES  
WILL BE POSSIBLE...ESPECIALLY IN AREAS THAT SEE TRAINING OF STORMS.  
THE ISOLATED NATURE OF THE HIGH AMOUNTS AND RELATIVE HIGH FFG VALUES  
ACROSS THE REGION SHOULD PRECLUDE THE NEED FOR A WATCH. THAT IS NOT  
TO SAY THAT ISOLATED FLASH FLOODING IN SOME AREAS COULD OCCUR OVER  
THE NEXT 24 HOURS.  
 

 
   
LONG TERM
 
(WEDNESDAY NIGHT THROUGH TUESDAY)  
UPDATED AT 345 PM EDT TUE JUL 16 2019  
   
..EXCESSIVE HEAT POSSIBLE FOR END OF WEEK THROUGH WEEKEND
 
 
 
HEIGHTS ALOFT BEGIN RISING WEDNESDAY NIGHT BEHIND THE DEPARTING  
WAVE. AT LEAST SCATTERED SHOWERS AND STORMS LOOK TO LINGER EAST OF I-  
65 INTO LATE WEDNESDAY EVENING. A PERIOD OF DRY WEATHER IS THEN  
LIKELY FOR MUCH OF THE AREA 06-12Z THURSDAY MORNING. THERE IS A WEAK  
NW TO SE ORIENTED BOUNDARY THAT DRIFTS EAST FROM WESTERN KY AND  
SOUTHERN IL THURSDAY MORNING. 12Z MODELS SHOW MOISTURE POOLING WITH  
SFC DEWPOINTS ABOVE 75 F ALONG WITH A SUBTLE WIND SHIFT. BEFORE  
SUBSTANTIAL UPPER RIDGING CAN BUILD OVERHEAD, THIS MAY BE ENOUGH FOR  
ISOLATED CONVECTION ON THURSDAY, PARTICULARLY WEST OF I-65 IN THE  
MORNING HOURS. COVERAGE SHOULD REMAIN LIMITED WITH ANTICYCLONIC FLOW  
ALOFT AND POOR MID-LEVEL LAPSE RATES. IT WILL REMAIN VERY HUMID IN  
THE WAKE OF THE CURRENT TROPICAL REMNANTS, HOWEVER. HEAT AND  
HUMIDITY WILL BE OPPRESSIVE. AFTERNOON HIGHS WILL REACH THE UPPER  
80S TO MID 90S WITH MAXIMUM HEAT INDICES IN THE UPPER 90S TO MID  
100S.  
 
CONFIDENCE IN MEDIUM RANGE GUIDANCE IS FAIRLY HIGH IN ITS DEPICTION  
OF A 593-594 MID-LEVEL RIDGE BUILDING OVER THE LOWER OHIO VALLEY  
FRIDAY INTO SATURDAY. AFTERNOON HIGHS SHOULD HAVE NO TROUBLE  
REACHING THE LOW TO MID 90S BOTH DAYS WITH PEAK HEAT INDICES OF 100-  
110 DEGREES. WILL HIGHLIGHT THE HEAT AND HUMIDITY IN AN SPS AND THE  
HWO FOR NOW, BUT WILL LIKELY NEED A HEAT ADVISORY LATE IN THE WEEK.  
 
THE CHANCES FOR PRECIP RETURN SUNDAY INTO EARLY NEXT WEEK. UPPER  
RIDGE WILL GRADUALLY RETROGRADE WESTWARD, AND A LARGE NORTHERN  
TROUGH DROPS SOUTHEAST OVER THE GREAT LAKES AND NORTHEAST US. A SFC  
COLD FRONT SHOULD DROP SOUTH THROUGH THE AREA IN THE MONDAY TIME  
FRAME, SO BUMPED UP RAIN CHANCES FOR EARLY NEXT WEEK.  
 

 
   
AVIATION
 
(18Z TAF ISSUANCE)  
UPDATED AT 111 PM EDT TUE JUL 16 2019  
 
REMNANTS OF TROPICAL CYCLONE BARRY WILL LIFT NORTHEASTWARD THROUGH  
THE NORTHERN OHIO VALLEY THIS AFTERNOON AND EVENING. WITH THIS  
FEATURE APPROACHING, WE'LL SEE MORE WIDESPREAD SHOWER AND  
THUNDERSTORM ACTIVITY. THIS ACTIVITY IS LIKELY TO AFFECT  
KHNB/KBWG/KSDF THROUGH THE AFTERNOON AND EVENING. SOME ISOLATED  
SHOWERS AND STORMS MAY DEVELOP OUT IN THE I-75 CORRIDOR NEAR KLEX,  
BUT MORE WIDESPREAD COVERAGE OVER THERE WILL LIKELY NOT OCCUR UNTIL  
AROUND 17/00Z. WINDS WILL BE GUSTY THIS AFTERNOON OUT OF THE  
SOUTHWEST WITH SUSTAINED SPEEDS OF 10-15 KNOTS AND GUSTS TO 25 KTS.  
 
FOR THE OVERNIGHT PERIOD, SCATTERED CONVECTION WILL BE POSSIBLE  
OVERNIGHT SO WILL CONTINUE A MENTION OF VCSH IN THE TAFS. WINDS  
WILL LIKELY REMAIN ELEVATED OVERNIGHT WITH SPEEDS IN THE 10-12KT  
RANGE. MODEL GUIDANCE SUGGESTS WE'LL SEE CEILING BUILD DOWN INTO  
THE MVFR RANGE AFTER 17/10Z.  
 

 
   
LMK WATCHES/WARNINGS/ADVISORIES
 
 
IN...NONE.  
KY...NONE.  

 
 

 
 
SHORT TERM...MJ  
LONG TERM...EBW  
AVIATION.....MJ  
 
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