South of a slow moving front across Illinois and Indiana, scattered convection initiated across central Kentucky in the warm sector. A few of the stronger storms caused scattered wind damage, isolated flash flooding, and a fire caused by lightning.
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Deaths and injuries are direct and indirect together, as the offices filed them. Damage is property and crops in the dollars of the year, not adjusted for inflation, and only where an office estimated it.
The episode as NWS LMK wrote it up.
South of a slow moving front across Illinois and Indiana, scattered convection initiated across central Kentucky in the warm sector. A few of the stronger storms caused scattered wind damage, isolated flash flooding, and a fire caused by lightning.
The local office's own words before the first event, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.
NWS Louisville, KY wrote its last area forecast discussion before the first event at Jul 16, 12:26 PM EST, 49 minutes earlier.
Area Forecast Discussion National Weather Service Louisville KY 126 PM EDT Fri Jul 16 2021 ...Updated Aviation Discussion... .Forecast Update... Issued at 1155 AM EDT Fri Jul 16 2021 Slow-moving cold front draped across Illinois and Indiana will remain a primary focus for convection, but we have a very moist and moderately unstable air mass over the Ohio Valley. Without any cap, we are starting to see isolated to widely scattered showers and a few T-storms develop as convective temperatures have been reached, mainly east of Interstate 65. Given the instability and weak shear, there is a modest pulse threat limited by modest values of downdraft CAPE, and heavy rainfall should be brief. Look for convection to remain scattered and disorganized through the afternoon. There's a hint of a couple of MCVs trying to develop along the front, and these could provide a focus for a bit more organized convection later tonight. Still more of a heavy rain threat with storm motion parallel to the slow-moving boundary, with wind as a secondary threat. && .Short Term...(Today and tonight) Issued at 234 AM EDT Fri Jul 16 2021 Showers and thunderstorms are ongoing across portions of southern Illinois and central Indiana this morning. All of this activity is out ahead of a weak cold front currently across northern IL/IN/OH. 850-700mb fields indicate a good fetch of Gulf of Mexico moisture into the Ohio Valley while weak convergence at these levels is aiding to initiate and sustain convective development. Outflow boundaries at the surface have also helped to fire off new convection, some of which have already clipped our southern Indiana counties per KVWX signatures. Activity across northern parts of our region through the remaining morning hours should remain isolated and not be very impactful. As we progress through the day, the frontal boundary to our north will slowly slide southward. A belt of modest 850-700mb flow will also shift ever so slightly southward, putting us in a favorable region to see additional shower and storm development this afternoon and evening. Most models hone in on an enhancement in the low to mid level winds this afternoon through the early overnight hours, which should aid in increasing our PWATs (currently 1.4-1.6") to +2" while also providing us some marginal effective deep layer shear. This will result in thunderstorms capable of torrential downpours and wet downbursts with gusty winds. The marginal effective deep layer shear could also aid in organizing convection into broken linear structures, as depicted by some CAMs, and a greater wind threat would be possible in those scenarios. Localized flash flooding will also be possible in areas that see repeated storms, particularly if boundaries form parallel to storm motions. Activity is likely to start tapering down after midnight as storms push off to the north and east, but it's possible a second wave of convection may develop in its wake during the early morning hours Saturday. Still quite a bit of uncertainty in how things may evolve, but something to certainly watch. .Long Term...(Saturday through Thursday) Issued at 245 AM EDT Fri Jul 16 2021 ...Occasional Showers and Thunderstorms This Weekend... Saturday begins with upper level ridging over the Desert Southwest, which models have strengthening and building northward over the Four Corners. An upper level trof centered over the Great Lakes extends southward into the Mid-MS Valley. A modest SW LLJ will be in the process of exiting to the northeast with sfc low pressure in the vicinity of Lake Erie. Sfc cold front will be draped SW through southern IN, and a moist airmass characterized by PWATs of 1.8-2.0 inches will be in place along and south of the boundary. A mid-level shortwave trof shifts east across KY during the day, and winds through the low to mid levels of the atmosphere diminish during the afternoon and evening hours. Scattered showers are likely to be ongoing Saturday morning, and quite a bit of cloud cover is likely to limit destabilization to a degree. MLCAPE near 1000 J/kg seems possible, but very weak shear will result in pulse storms. Given the synoptic features above, plenty of lift and moisture should result in scattered to numerous showers and storms in the afternoon and evening. Primary concern will be isolated flash flooding, especially in areas that see repeated rounds of heavy rainfall between now and Saturday afternoon. Highs will be limited to the low to mid 80s by clouds/convection. Upper level trof continues to drop south over the area through the second half of the weekend. The sfc boundary stalls and washes out over KY/TN. Diurnally driven convection appears likely once again Sunday, especially over central and southern Kentucky. Chance PoPs for southern Indiana. Omega block takes shape over western and central CONUS Monday- Wednesday. Upper trof axis shifts off to the south and east Monday into Monday night, and drier air gradually filters in from the north. Isolated to scattered showers/storms still look possible Monday, but overall coverage and heavy rainfall potential will be much lower compared to Sunday. Highest PoPs are across southern KY Monday afternoon. Highs should have no trouble reaching the mid 80s on Monday, and temperatures steadily climb going into the middle of the week with mainly dry conditions. Highs of 85-90 F are likely Wednesday. Have low rain chances creeping back into the forecast by late next week, but confidence in the details is low for Thu/Fri. && .Aviation...(18Z TAF Issuance) Issued at 115 PM EDT Fri Jul 16 2021 Scattered showers and a few TS have developed near HNB and SDF, and that's enough to warrant VCTS at initialization. However most of this will be missing the airfields and pushing off to the east later this afternoon. Could see something similar in LEX a bit later, but confidence is even lower there. BWG should remain dry but scattered TCU could make for some bumpy approaches. As a slow-moving front drops in on us from the north this evening, we'll see better chances for storms to directly affect HNB and SDF, and eventually BWG if another complex gets organized over western KY/TN. For now will limit the TEMPO and vis restrictions to HNB, but that could expand later. Once the convection pushes through by daybreak Sat, look for a period of MVFR ceilings which will most likely be below 2000 feet. Highest confidence in HNB which will be post-frontal by that point, and least confidence in LEX. && .LMK WATCHES/WARNINGS/ADVISORIES... IN...None. KY...None. && Update...RAS Short Term...DM Long Term...EBW Aviation...RAS
Hazardous Weather Outlook National Weather Service Louisville KY 1151 AM EDT Fri Jul 16 2021 INZ076>079-083-084-089>092-KYZ023>043-045>049-053>057-061>067- 070>078-081-082-171600- Orange-Washington-Scott-Jefferson-Dubois-Crawford-Perry-Harrison- Floyd-Clark-Hancock-Breckinridge-Meade-Ohio-Grayson-Hardin-Bullitt- Oldham-Trimble-Henry-Shelby-Franklin-Spencer-Anderson-Woodford- Fayette-Bourbon-Nicholas-Nelson-Mercer-Jessamine-Larue-Marion-Boyle- Garrard-Madison-Butler-Edmonson-Hart-Green-Taylor-Casey-Lincoln- Logan-Warren-Simpson-Allen-Barren-Monroe-Metcalfe-Adair-Russell- Cumberland-Clinton- Including the cities of Paoli, Salem, Scottsburg, Madison, Jasper, English, Tell City, Corydon, New Albany, Jeffersonville, Lewisport, Hawesville, Hardinsburg, Brandenburg, Hartford, Leitchfield, Elizabethtown, Shepherdsville, Louisville, La Grange, Bedford, Milton, New Castle, Shelbyville, Frankfort, Georgetown, Cynthiana, Taylorsville, Lawrenceburg, Versailles, Lexington, Paris, Carlisle, Bardstown, Springfield, Harrodsburg, Nicholasville, Winchester, Hodgenville, Lebanon, Danville, Lancaster, Richmond, Morgantown, Brownsville, Horse Cave, Greensburg, Campbellsville, Liberty, Stanford, Russellville, Bowling Green, Franklin, Providence, Scottsville, Glasgow, Tompkinsville, Edmonton, Columbia, Jamestown, Burkesville, and Albany 1151 AM EDT Fri Jul 16 2021 /1051 AM CDT Fri Jul 16 2021/ This hazardous weather outlook is for portions of south central Indiana and Central Kentucky. .DAY ONE...This Afternoon and Tonight. Scattered to numerous showers and storms will develop late this afternoon and continue into the overnight hours. Heavy rainfall could result in localized flooding, and some of the stronger storms could produce gusty winds. .DAYS TWO THROUGH SEVEN...Saturday through Thursday. Multiple rounds of showers and storms are possible into the weekend. The primary hazard will be heavy rain, which could lead to localized flooding. Locally gusty winds will also be possible with the stronger storms. .SPOTTER INFORMATION STATEMENT... Spotters are invited to submit reports to the National Weather Service. && More information, along with other weather, hydrological and climate information can be found at weather.gov/louisville. DM/EBW/RAS
Special Weather Statement
National Weather Service Louisville KY
159 PM EDT Fri Jul 16 2021
KYZ029-161815-
Bullitt-
159 PM EDT Fri Jul 16 2021
...A STRONG THUNDERSTORM WILL AFFECT NORTHEASTERN BULLITT COUNTY...
At 159 PM EDT, a strong thunderstorm was located over Shepherdsville,
moving northeast at 20 mph.
Wind gusts up to 50 mph are possible with this storm.
Locations impacted include...
Shepherdsville, Mount Washington, Hebron Estates and Gap In Knob.
LAT...LON 3804 8551 3798 8570 3802 8572 3808 8561
3808 8560 3807 8555 3808 8554 3808 8553
TIME...MOT...LOC 1759Z 241DEG 19KT 3801 8569
CGSpecial Weather Statement National Weather Service Louisville KY 204 PM EDT Fri Jul 16 2021 KYZ066-067-161830- Lincoln-Casey- 204 PM EDT Fri Jul 16 2021 ...A STRONG THUNDERSTORM WILL AFFECT CENTRAL LINCOLN AND EAST CENTRAL CASEY COUNTIES... At 204 PM EDT, a strong thunderstorm was located 10 miles northeast of Liberty, moving northeast at 25 mph. Wind gusts up to 50 mph and pea size hail are possible with this storm. Locations impacted include... South Fork, Boneyville, Kings Mountain, Jumbo, Ottenheim, Mount Salem, Geneva, Halls Gap, Maywood and New Salem. LAT...LON 3734 8476 3740 8483 3755 8472 3743 8453 TIME...MOT...LOC 1804Z 217DEG 22KT 3739 8477 CG
The national radar mosaic for the moment the first event began.
3 thunderstorm wind, 1 flash flood, 1 lightning. Local standard time, as filed.
A tree fell down near the intersection of Kentucky 70 and Kentucky 501.
A tree fell down over Hunter Lane.
Highway 49 near Arthur Mattingly Road was impassable due to high water.
Trees brought down power lines.
A transformer was struck by lightning and caught on fire. Power lines were down across Lakeview Drive. Cost of damage is unknown.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Kentucky in 2021Every state in 2021This day in weather historyWarnings in Kentucky, July 2021
NOAA National Centers for Environmental Information, Storm Events Database, compiled from the National Weather Service’s monthly Storm Data. Complete through 2026-06; NCEI adds each month about 75 days after it ends and revises past years a few times a year. Rebuilt 2026-09-24. Each event’s entry at NCEI: 975710, 975711, 975708, 975712, 975709.