A bout of summer-time excessive heat is set to blast most of the state through at least Wednesday. According to the National Weather Service, daytime highs into the 90s, coupled with high humidity, will have heat index values topping 100 degrees for most Iowans starting today. The extra punch of humidity comes from 8-12″ of rain that has fallen over most of the state since mid-June and the corn crop remaining in strong condition across Iowa.