One more related graph shows normalized home run rate vs Cd (both monthly averages). The home run rate is controlled for exit velocity, launch angle, and air density (especially temperature), so that these factors do not enter into the rate. Rates are ~20% greater in June,July than in April,May.
Alan NathanJuly update on Cd values, which seem to be trending upward. Fly ball distances for given LA are same in July as in June, with both greater than April and May. I will continue to post monthly update for remainder of season.
