The best way that Brooklyn Ramblings has found to beat the heat is to get out on the water with the Gowanus Canal Canoe Club - it’s at least ten degrees cooler on the water, and the bay breeze is great, once you get out there. (The canal breeze isn’t quite as refreshing, but it is bracing!)
Canoeing launches from Carroll Gardens, at the end of 2nd Street on the north side of the canal. They run a bunch of free public programs throughout the summer. This upcoming Saturday, there’s a Red Hook discovery tour and shoreline cleaning run in conjunction with Red Hook Boaters, from 9 am - 1 pm, launching from the Louis Valentino Jr. park pier.
If you want to go whenever, on your own schedule, joining the canoe club allows you to take out a canoe whenever one is free. Brooklyn Ramblings has been a member now for about three years, and lemme tell you, there’s nothing like getting off work and being out on the water half an hour later. Urban canoeing at its best.