National Weather Service United States Department of Commerce


…Most tornadoes in a single day during the month of August…

…6 tornadoes impacted Southeast Michigan, with 7 tornadoes statewide…

Rapidly developing thunderstorms begin 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. 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 (1-2” 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.