I’ve had same issue and I’m on Long Island too so I know the weather well
I have these one my tanks Zoo Med Aqua Cool Aquarium Cooling Fan, Black https://www.amazon.com/dp/B0049RNVXI/ref=cm_sw_r_cp_api_glt_fabc_VPDRG043BER8M3JB08WM?_encoding=UTF8&psc=1
But they only lower tank about 4-5 degrees after six hours or so …
I turn off my tank heater during day and use this tank fan . I also put a box fan on. Stool near the tank so it blows across the surface of the water … lower the water a bit so you can go without the tank lid .
I also freeze a few zip lock bags of tank water and use those if tank gets really heated on a super hot day
I also have a hand held digital themonter (so) and I take readings all the time … it might be helpful to get one of the digital ones that sticks on tank so you can constantly see the temp …
At night in NY TEMPS DROP so always keep an eye out .