The threat of thunderstorms for this afternoon/evening is still present, but somewhat smaller than predicted this morning. We still have a small threat of severe weather, but that has also diminished somewhat since this morning; the primary threat from most of these storms will be heavy rain, with only a small chance of damaging wind or large hail.
We can expect scattered storms this afternoon/evening across southern/SE MI, with only a slight chance of any storms becoming severe. Severe storms are more likely south of I-94, so Ann Arbor should probably see only rain and average thunderstorms, if anything at all. Predicting exactly if/when any of these storms will hit downtown Ann Arbor specifically is difficult.
This all bodes well for Top of the Park tonight!
Tomorrow (Wednesday) might be more interesting, as a cold front moving into the area after midnight brings an increased risk of severe weather.
Additional Reading: NWS Detroit briefing, 3pm June 25