Washington Sports Clubs’ summer special is back this year, and it couldn’t have come at a better—or hotter—time. Starting Thursday, every time the thermometer hits 90 degrees in Washington, all WSC gyms will be open to the public.

There are a few caveats: You must be 18 years or older and show a photo ID, and the offer is not valid on Monday through Thursday between 5:30 and 7:30 PM. The deal lasts until August 31 and is valid at city gyms, including New York Sports Clubs, Boston Sports Clubs, and Philadelphia Sports Clubs.

Tip: There are 16 locations in Washington, but we recommend hitting up one that has a pool. WSC in Columbia Heights offers Aqua Zumba on Wednesday at 8 PM.