Inside the wildly welcoming jazz party that’s become a D.C. ritual

David Weiner is washing dishes. It’s the 21st of the month, which means his D.C. rowhouse is full of people. Some are friends he’s known for decades, others are people he’s never met. There’s a jazz band playing standards downstairs, and the music is floating up through the house. Some of the musicians are professionals, others are amateurs who showed up with an instrument and enough courage — liquid or otherwise — to join in.