Goldfish and hot temperatures ?

It's almost 100 degrees here in Philadelphia, and my goldfish lives in a room without air conditioning. I have a Black Moor in a 10 gallon tank (I know it's small, you don't have to tell me)... The water feels cool to the touch, but I don't have a thermometer right now. What can I do to make sure my fish is alright and the water is not getting too warm? Any signs to look out for?