You don't need a drysuit. 7mm works great and less expensive, too. If you get a chance, take a weekend trip to the 1000 Islands. The wrecks are plentiful and the scenery is great.
Having a drysuit gives you options. You can dive a drysuit year round' with adjusted layering. While a 7mm might be an easy option during the summer and early fall - you will get cold when the water goes into the 50's & 40's during the late fall and winter months.
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