Thanks for the extensive replies! That calculator is a huge help, as I have been trying to figure out how to determine the heat index and that pretty much does it for me.
I upgraded my humidifier to a 9 gallon per day output from a 1 gallon per day. It maintained a pretty steady 47% throughout class with the average temp of 97. It was 4 degrees outside so it was hard to maintain the room temp much higher without going to a 240 volt mega heater.