Cool summer here in Charleston too. Only a few days above 90 and very few where it pushed 100.
Last July we had 29 days out of 31 above 90 degrees and 7 of them above 100. This year in July we had 13 days above 90 and it never reached 100. The days when it did get above 90, it was 91, 93, 94.
Alot of rain, which sucks for the fishing and shrimping, but pretty comfortable summer overall. So far in August, it hit 91 one day and 90 another and thats it.