In a three-day period from August 2–4, 2023, significant flooding occurred across northwestern Tennessee, southwestern Kentucky, and southeastern Missouri in the United States.

In the early morning hours of August 2, convection developed across northern Missouri in an increased low-level convergence zone, precipitable water values around 2 inches, and a moist, moderately unstable airmass with most-unstable convective available potential energy (CAPE) around 2000 j/kg.

[1] The strengthening low-level convergence zone paralleled a west-northwesterly flow aloft, allowing training convection to occur.

[3] Thereafter, on the evening hours, a frontal boundary over central Kansas, along with a humid and moist airmass and instability in southern Missouri, allowed convection to develop and produce heavy rainfall across central Missouri, and west of the Greater St. Louis area as a high risk of excessive rainfall was issued.

[4] Training showers and thunderstorms developed across portions of southeastern Missouri and southern Illinois along an elevated convergence axis zone as it moved southeastward towards southwestern Indiana and western Kentucky.

[8] In the early morning hours of August 4, additional showers and thunderstorms developed in a corridor extending from central Missouri to northern Alabama due to an increased convective instability, a surface stationary front located over Memphis, Tennessee, and a deep-layer mean flow which resulted in repeating rounds of thunderstorms that moved southeastward over the same areas which had already received heavy rainfall.

[17] The National Weather Service in Memphis, Tennessee called the flooding in Union City and surrounding areas "catastrophic".

[36] Gerald received nearly 4 inches (100 mm) in 30 minutes according to the Gerald-Rosebud Fire Protection District, flooding basements and cars and prompting a water rescue.

[40][41] The Tennessee Highway Patrol assisted with the Obion County Sheriff and Union City law enforcement.