Numerous showers and thunderstorms occurred along a strong cold front that extended from Lake Erie to the lower Ohio Valley. Isolated flash flooding occurred.
Every event with a place to put it. Tap one for its entry below.
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 PAH wrote it up.
Numerous showers and thunderstorms occurred along a strong cold front that extended from Lake Erie to the lower Ohio Valley. Isolated flash flooding occurred.
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 Paducah, KY wrote its last area forecast discussion before the first event at Jun 21, 5:43 AM CST, 5 hours 59 minutes earlier.
Area Forecast Discussion National Weather Service Paducah KY 643 AM CDT Mon Jun 21 2021 .UPDATE... Issued at 642 AM CDT Mon Jun 21 2021 Updated the aviation section for the 12Z TAF issuance. && .SHORT TERM...(Today through Wednesday night) Issued at 418 AM CDT Mon Jun 21 2021 Showers and a couple thunderstorms from a weakening storm line have held on into southwestern Illinois the last couple hours. Somewhat close to the HRRR, these storms are expected to diminish over the next couple hours, leaving light showers. A few sprinkles to light showers have formed along a SW to NE line in Western Kentucky, which is roughly the most this will amount to. With the arrival of storms, winds have shifted to westerly at due to the outflow boundary with the weakened storm line rather than the cold front, which is further to the northwest. Temperatures remain warm ahead of the outflow boundary, with early morning lows in the lower 70s for northwestern portions of the CWA and the mid 70s south/east. Aside from gusts around 20 mph with the outflow boundary, winds have been mostly under 10 mph. Winds are expected to increase closer to dawn as the cold front approaches the northwestern border of the CWA. The cold front is still on pace to track to the Ohio River mid- morning. Locations north/west will have daytime highs in the early morning at or below 80, while locations south/east will warm into the low to possibly mid 80s before rain develops. Most models begin to develop showers and storms, primarily near and south of the Ohio River, with a fully developed line a couple hours later. This line will be the main focus of thunderstorm activity. A few strong storms and a severe storm or two are possible due to decent instability and mid-level lapse rates. Having formed near the Ohio River, and progressing southeastward, the main thunderstorm threat will be roughly noon to mid afternoon for Western Kentucky. The primary hazards with this line of storms will be gusty winds, frequent lightning, and heavy rain. Plenty of models develop additional stratiform rain to the northwest of the main front in the afternoon to evening hours, ahead of an evening upper-level trough passage. A few thunderstorms will be possible, but instability will be very weak behind the cold front and shear will be very low, so isolated lightning and brief heavy rain are the expected hazards with this portion of the event. With the main line forming near and parallel to the Ohio River (and extending through Southeast Missouri), areas further north/west are likely to have closer to a quarter of an inch of rain, while far SE Missouri and W Kentucky are likely to see 1-1.5" of rain. Locally higher amounts could result in some isolated flooding issues. Recent dry weather and average soil moisture will help limit that concern. Behind the cold front, temperatures and dew points will drop significantly, leaving pleasant conditions for Tuesday and Wednesday after showers depart Monday night. Skies will clear with high pressure passing through the area. Highs will be in the upper 70s to near 80 Tuesday and in the lower 80s Wednesday. Lows are forecast to be in the mid-50s Monday and Tuesday nights and the lower 60s Wednesday night after a Wednesday wind shift to a more southerly direction. .LONG TERM...(Thursday through Sunday) Issued at 418 AM CDT Mon Jun 21 2021 By 12Z Thursday, the upper air charts feature a trough to our east across the Appalachians, and a high centered over Texas. Our region will be centered in the weak northwesterly flow between the two systems. At the surface, high pressure will be well to our east and a cold front will be situated from the central Plains states up into the western Great lakes. Low level flow will be southerly to southeasterly early Thursday, but become more southerly and increase as we head through the day. This will aid in boosting temperatures well into the upper 80 by afternoon. There will be convection ongoing at the start of the period in association with that boundary to our northwest. Most of the deterministic models keep that activity tied to the boundary and out of our area, but the GFS and several of its ensemble members want to take that activity and dive it south into our CWA during the afternoon and evening. The NBM seems to have a more conservative approach and keeps only slight chances going for those periods, which is more in line with our current thinking based on the synoptic pattern. However, as we head into Friday and Saturday, we will see increasing unsettled weather unfold as the aforementioned front starts to make slow headway southeast, as an upper level trough eventually strengthens across the central Plains and into the upper Midwest Friday night into Saturday. The front will move into our area Friday night into Saturday and then stall out. Then, another area of low pressure will develop along it, which will prolong shower and thunderstorm activity into Saturday night and Sunday. The pattern becomes pretty messy beyond that, so it will be difficult to say when exactly this unsettled pattern will break. Therefore, the NBM likely PoPs look good for Friday through Saturday night, tapering off on Sunday and Sunday night a bit due to uncertainty. Given the very high PW values and surface dew points rising into the lower 70s across the area during this time frame, heavy downpours are highly likely with the threat of some minor flooding increasing, especially if we end up having multiple rounds of convection. Any severe threat appears marginal at this point, as instability and wind fields are not overly impressive, but could definitely support some organized convection. Cloudy conditions and expected rain on Friday and into the weekend should help keep high temperatures tempered and remain in the lower to mid 80s. && .AVIATION... Issued at 642 AM CDT Mon Jun 21 2021 A frontal passage today will be accompanied with cig reduction to MVFR for a few hours. Widespread shower and thunderstorm activity is expected to develop today along the front, with the main storm line organizing near the Ohio River late morning, then moving southeastward through the afternoon. Additional rain is expected behind this line for the late afternoon to evening hours, with a few embedded thunderstorms possible but unlikely enough to include that portion of thunder in the TAF. Southwesterly winds will shift towards the northwest as the cold front passes through. Winds will be gusty mid-morning through the early evening, with gusts up to 20-25 kts. Vsby drops to MVFR and briefly IFR will be possible with thunderstorms and/or heavy rain. Tonight, rain will end, winds will decrease, and skies will begin to clear. && .PAH WATCHES/WARNINGS/ADVISORIES... IL...None. MO...None. IN...None. KY...None. && UPDATE...ATL SHORT TERM...ATL LONG TERM...CW AVIATION...ATL
Hazardous Weather Outlook National Weather Service Paducah KY 1014 AM CDT Mon Jun 21 2021 ILZ075>078-080>094-INZ081-082-085>088-KYZ001>022-MOZ076-086-087- 100-107>112-114-221000- Jefferson-Wayne IL-Edwards-Wabash-Perry IL-Franklin-Hamilton- White-Jackson-Williamson-Saline-Gallatin-Union-Johnson-Pope- Hardin-Alexander-Pulaski-Massac-Gibson-Pike-Posey-Vanderburgh- Warrick-Spencer-Fulton-Hickman-Carlisle-Ballard-McCracken-Graves- Livingston-Marshall-Calloway-Crittenden-Lyon-Trigg-Caldwell- Union KY-Webster-Hopkins-Christian-Henderson-Daviess-McLean- Muhlenberg-Todd-Perry MO-Bollinger-Cape Girardeau-Wayne MO-Carter- Ripley-Butler-Stoddard-Scott-Mississippi-New Madrid- 1014 AM CDT Mon Jun 21 2021 This Hazardous Weather Outlook is for portions of southern Illinois, southwest Indiana, western Kentucky, and southeast Missouri. .DAY ONE...Today and Tonight Scattered thunderstorms are forecast through the afternoon, especially along and south of a line from Owensboro Kentucky to Poplar Bluff Missouri. Storms should push southeast out of the area by late afternoon. While a few strong to severe storms may result in damaging winds, locally heavy rain and lightning will be the primary concerns. .DAYS TWO THROUGH SEVEN...Tuesday through Sunday There is a chance of thunderstorms Thursday through Sunday. While localized strong to severe thunderstorms cannot be ruled out, the main concern appears to be heavy rain and localized flooding, mainly Friday into Saturday night. .SPOTTER INFORMATION STATEMENT... Spotter activation cannot be ruled out across southeast Missouri and western Kentucky today.
Special Weather Statement National Weather Service PADUCAH KY 1104 AM CDT Mon Jun 21 2021 KYZ001>013-015>017-020>022-MOZ112-114-211900- Fulton-Hickman-Carlisle-Ballard-McCracken-Graves-Livingston- Marshall-Calloway-Crittenden-Lyon-Trigg-Caldwell-Webster-Hopkins- Christian-McLean-Muhlenberg-Todd-Mississippi-New Madrid- Including the cities of Hickman, Clinton, Bardwell, Wickliffe, Paducah, Mayfield, Smithland, Benton, Murray, Marion, Eddyville, Cadiz, Princeton, Dixon, Madisonville, Hopkinsville, Calhoun, Greenville, Elkton, Charleston, and New Madrid 1104 AM CDT Mon Jun 21 2021 Scattered to numerous thunderstorms will move across the Missouri bootheel and western Kentucky through mid afternoon. Torrential rainfall is occurring with these storms with rates as high as 1 inch in 15 minutes possible. This may lead to some urban and small stream flooding and flooding of low lying or flood prone areas. Some of the stronger storms will also be capable of producing hail up to nickel sized and gusty winds of 40 to 50 mph.
The Ft Campbell radar (KHPX), 69 km away, was scanning. The volume nearest the first event began at 17:40 UTC.
1 flash flood. Local standard time, as filed.
Six inches of water was flowing across Highway 91 South.
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, June 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: 961289.