Around 1140 PM EDT…parts of extreme southwest Kalamazoo County experienced a combination of up to golfball sized hail and winds in excess of 80 mph. The greatest damage occurred west-southwest of Schoolcraft. An NWS damage survey determined that the winds were straight-line and not tornadic. The western sides of many homes had their siding shredded by the wind driven hail.
About a dozen irrigation pivots were destroyed and several trees were knocked down.
A Recreational Vehicle dealership had several of its vehicles rolled over.
Strong winds also pushed in garage doors allowing roofs to be peeled off of the building.
The X in the images below indicate where the greatest wind damage occurred. The thunderstorm that produced this damage was in the process of “bowing out”, meaning that it assumed the shape of a bow by the time it reached Schoolcraft. This type of radar signature is frequently associated with damaging winds. However, it is unusual for the winds to be accompanied by such large hail.
This storm was moving east along a warm front. Strong vertical wind shear combined with concentrated atmospheric instability near the front allowed this storm to become very severe. Storms farther north that crossed the Grand Rapids area did not produce strong winds due to the cold air that was north of the warm front.