In loving memory of the Sunday Blues Jams at the former Somerville institution Johnny D’s Uptown, the Porch Southern Fare & Juke Joint at River’s Edge is now holding its own Sunday afternoon jam sessions from 1 to 4 p.m. Colin Dwyer hosts the event, presented in the spirit of offering a great networking and community building event. Participation in the jam is free and on a first come, first served basis.