Northeast here.
I dive dry (DUI TLS SE) all year even in the warmest months. Even if the air temp is in the 90's and the water over the thermocline is around 75, the temperature under the thermocline rarely gets warmer than 41 so I would need my old 2x7 mm wetsuit anyway.
I use a 3 mm shorty in the caribbean and sometimes in the river (Thousand Islands) when it reaches 70+ F
I dive dry (DUI TLS SE) all year even in the warmest months. Even if the air temp is in the 90's and the water over the thermocline is around 75, the temperature under the thermocline rarely gets warmer than 41 so I would need my old 2x7 mm wetsuit anyway.
I use a 3 mm shorty in the caribbean and sometimes in the river (Thousand Islands) when it reaches 70+ F