Episode narrative: Thunderstorms producing torrential rainfall led to flooding in the Detroit metro area early Thursday morning (August 24th). Western Wayne county into Monroe county was hardest hit resulting in widespread residential flooding, road closures, and stranded vehicles. Most notable was the closure of Dingell Drive at Detroit Metro Airport which cut off access to the McNamara terminal for several hours. A lengthy closure of I-94 at I-275 was also reported. Numerous rainfall totals in the 3 to 5 inch range were reported mostly in the 6 hour period from midnight to 6 AM. The highest total was 7.36 inches from a CoCoRaHS station in Belleville, a 24 hour total nearly all of which fell during this event.

A second round of rapidly developing thunderstorms began to pop up over Central and Southwest Lower Michigan by the early evening hours of August 24th, with the exceptional moisture and instability in place over southern Lower Michigan. The storms quickly grew upscale and became severe, leading to a west-east line of severe thunderstorms which dropped south through southeast Michigan during the evening hours.

Strong winds in the mid levels allowed for damaging winds to be the primary hazard, with areas of southeast Michigan seeing 60-80 MPH wind gusts which lead to extensive tree damage and power outages, along with some structural damage to homes. At the peak, close to 500,000 customers lost power in southern lower Michigan.  A surface low tracking through southern Lower Michigan was able to help spawn tornadoes, with an EF-2 developing over northeast Ingham. This tornado weakened and tracked into Livingston county near Fowlerville before dissipating. This 12 mile track tornado was by far the strongest and longest duration one of the day, and also resulted in 1 fatality as cars were flipped on I-69 in Ingham county. Short lived-weak QLCS tornadoes spun up over Wayne and northeast Monroe counties as the intense thunderstorm complex exited the state around Midnight. Winds with these tornadoes reached 80-105 mph, but even a few wet micro-burst/straight line winds produced wind gusts to 90 mph embedded in the line of storms.

Rainfall rates were intense (1-2ï¿½ï¿½ï¿½ per hr), but due to the rapid movement of the complex/storms (45-60 MPH), rainfall amounts stayed under 3 inches just about everywhere. Highest rainfall amounts of 1.5-3 inches occurred along the M-59 corridor up to I-69 corridor. Due to heavy rainfall from the previous day (1-3 inches with isolated 5-7 inch totals in Wayne/Monroe counties), even locations which received amounts under 1.5 inches experienced some flooding, mostly low lying/flood prone locations.  The Lower River Rouge in Wayne county experienced major flooding and Clinton River in Macomb experienced moderate flooding.

Finally, prolific lightning was observed with the thunderstorm complex as it moved through southeast Michigan, producing thousands of cloud to ground strikes, with a good percentage of them being the stronger positive charged ones.

Tornado event in MONROE County, MICHIGAN
Start: 24-AUG-23 21:38:00
End: 24-AUG-23 21:43:00
Direct deaths: 0
Property damage: 1.00M
Event narrative: The weak tornado touched down in a farm field in Ash Township north of Newport Road and half a mile west of North Telegraph Road. The tornado tracked southeast and hit Frenchtown Villa Mobile Home Park where the bulk of the damage occurred on the north side of the park. Roofs were torn off and a manufactured home was flipped over. Other damage included shingle and roof damage on the northeast side of the park. Maximum winds were estimated to be 100 mph. The tornado continued to track southeast and crossed over I-75 by the Meijer Distribution Center where large tree limbs were downed to the east of the center. As the tornado continued southeast, several large tree limbs were downed with leaning power poles noted. The tornado dissipated in a farm field about half a mile east of North Dixie Highway and south of Post Road in Frenchtown Township in Monroe County.