On the evening of Friday, June 4th, severe thunderstorms moved from Eagle in Clinton County through Lansing and east to Haslett in Ingham County before weakening. The storms produced damaging winds gusts up to 75 mph in Eagle and near 80 mph in a neighborhood just west of Lake Lansing. Large amounts of hail falling from high up in the storm produced large pools of dense cold air that accelerated towards the ground resulting in extreme localized wind gusts at the surface called microbursts. The graphic below shows three microbursts that occured along the track of the storms. A few damage pictures from the Eagle and Lake Lansing area are shown below followed by a radar animation of the descending hail in the storms.
( Click on photo to enlarge )
Below are several pictures of wind damage caused by the storms. The first three are from Eagle and the last from the Lake Lansing area.
( Click on a photo to enlarge )
The animation below is from the NWS 88D Doppler Radar in Grand Rapids. It shows a vertical cross section of the storms as they moved from west of Eagle through Lansing to Haslett at the end of the loop. The vertical coordinate is thousands of feet so that 10 kft would be 10,000 ft above the ground. Notice that the thunderstorms reach upwards of 50,000 ft tall or roughly 10 miles tall!
Areas of hail or "hail cores" are depicted as the pink or rose shading surrounded by the dark reds which are heavy rains. Notice how the hail cores first develop at roughly 20,000 ft or between 4 and 5 miles above the ground and then desend in subsequent frames towards the ground. The microburst wind damage in Eagle resulted from the descent of the first hail core. The largest and most severe area of damage occurred just west of Lake Lansing as the entire hail core collapsed. The core collapse can be seen towards the end of the loop.
( Click on animation to enlarge - the full resolution loop is about 5 Megabytes )