A training thunderstorm complex during the night of June 27th into the 28th produced significant flash flooding, as well as minor river flooding on the Green River. The maximum axis of rainfall amounts of 4 to 8 inches occurred over portions of northwest Kentucky, just south of the cities of Owensboro and Henderson. A weak mid-level disturbance advanced east early in the morning across eastern IL. This energy helped foster thunderstorm activity across portions of southern IL, southern IN, and Kentucky. The air mass around the southern flank of the disturbance was still at least modestly unstable with mixed layer capes around 1000 j/kg early in the morning. A west-southwest low-level wind flow between 30 and 40 knots focused strong moisture transport into the storms. The storms trained over the same area for three to five hours. Precipitable water values across the region were on the order of 1.7 to 1.9 inches, fueling rainfall rates exceeding 2 inches per hour.

Thunderstorm Wind in TODD, KENTUCKY
From 28-JUN-20 15:30:00 to 28-JUN-20 15:30:00 (CST-6)
Location: ELKTON
Magnitude: 56.00 MG
Property damage: 3.00K
Crop damage: 0.00K
Reported by: Mesonet

A wind gust to 65 mph was measured at the Kentucky mesonet site in Todd County. A nearby carport structure was blown over.

Flash Flood in HENDERSON, KENTUCKY
From 28-JUN-20 07:00:00 to 28-JUN-20 18:45:00 (CST-6)
Location: HENDERSON
Flood cause: Heavy Rain
Property damage: 100.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Flash flooding of roads became rather widespread. Some roads were impassable. Water rescues were conducted from vehicles that were stranded in floodwaters. Rainfall amounts were heaviest in southeast parts of the county, where close to 8 inches fell in a 48-hour period. Much of that rain fell early on the 28th. A trained spotter just east of Corydon measured 7.85 inches during the daytime hours on the 28th.

Flash Flood in MCLEAN, KENTUCKY
From 28-JUN-20 07:41:00 to 28-JUN-20 19:00:00 (CST-6)
Location: CALHOUN
Flood cause: Heavy Rain
Property damage: 250.00K
Crop damage: 0.00K
Reported by: Public

Widespread flash flooding was reported. Several water rescues were conducted, including a few from homes and a few from vehicles. Major roads were closed, including Highways 431, 136, and 81. The majority of emergencies were in the mid-morning hours. Some roads remained closed into the evening. A state of emergency was declared by county government officials. The mesonet site five miles northwest of Calhoun measured 6.74 inches in 48 hours, but much of that fell on the morning of the 28th.

Flash Flood in DAVIESS, KENTUCKY
From 28-JUN-20 07:45:00 to 28-JUN-20 19:00:00 (CST-6)
Location: OWENSBORO
Flood cause: Heavy Rain
Property damage: 100.00K
Crop damage: 0.00K
Reported by: Broadcast Media

Numerous water rescues were conducted due to vehicles in floodwaters across the county, including the city of Owensboro. A trained spotter at Utica measured 5.34 inches by mid-morning, with rain still falling.

Flood in MUHLENBERG, KENTUCKY
From 28-JUN-20 09:00:00 to 28-JUN-20 12:00:00 (CST-6)
Location: CENTRAL CITY
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

Street flooding was reported. A report was received from the public of 4.50 inches of rain, most of which fell in three hours.

Flood in MUHLENBERG, KENTUCKY
From 29-JUN-20 14:00:00 to 30-JUN-20 23:59:00 (CST-6)
Location: PARADISE
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 5.00K
Reported by: River/Stream Gage

Minor flooding of the Green River inundated low-lying woods, fields, and some croplands. The flooding continued into July.