Seriously, it has been a cool summer, or at least a cool July. Here's an article from the NWS in Indianapolis.
July has gotten off to quite a cool start here in Central Indiana this year. Only one day this month has featured a high temperature above normal, and no temperatures have reached the 90s yet this month.
After the first 15 days of the month, our average daily high temperature has been only 79.1F (26.2C) degrees. For comparison's sake, a normal first half of July should experience an average daily high temperature of 85.4F (29.7C) degrees.
This is quite an unusual occurrence, and the last time the first half of the month had a cooler average daily high temperature was all the way back in 1960. In that year, the average daily high temperature through the first 15 days was 78.9F (26.1C) degrees.
July of 1960 ended up being the second coolest July ever. The latest 8-14 day extended outlook continues to indicate a high likelihood of below normal temperatures.