1. Forecast: Increasing clouds, with a high near 90.
2. Old Ironsides Sails: The U.S.S. Constitution has a big weekend ahead of it——but Friday through Sunday are packed with other Constitution-centric events as well. .
3. Register to Vote: Friday is the last day to register to vote in the Sept. 6 primary election. JP-related races include a primary challenge to Sen. Sonia Chang-Díaz by perennial hopeful Roy Owens.
4. Spanish Music Festival: If you're into early music, or just curious to hear the sounds of forgotten eras, St. John's Church in JP is the place to be today. There are two sessions of Spanish opera and zarzuela, and $10. It's part of the IBERICA 2012 Early Music Festival.
5. Boston Green Fest: Catch the Orange Line to State Street just about anytime Friday, Saturday or Sunday for the Boston Green Fest that's taken over City Hall Plaza. Too many events to list here. Check out the details.