Mark your calendars, Bonnaroo fans. The Tennessee festival will announce its 2013 lineup via the Bonnaroo Live Announcement Megathon, aka B.L.A.M., on Feb. 19 at 1PM ET. But this is no ordinary festival lineup reveal. It's bigger than that. Way bigger.

It's an event where the inimitable "Weird Al" Yankovic will be on hand to emcee. There will also be some ort of "pre-game show" featuring video of performances from previous Bonnaroo acts.

The announcement will take place at the Bonnaroo 365 channel on YouTube (embedded below, so stop back and watch next week!) and be syndicated here. The 60-minute event will feature a live performance by Portugal. The Man.

At noon ET, an hour before the announcement starts, the history of the festival will be celebrated with a stream of classic and historic Bonnaroo performances by Metallica, Tom Petty, Bruce Springsteen, Bon Iver, the White Stripes and more. Following the announcement event, a surprise, one-time only classic Bonnaroo performance will be streamed.

Additionally, the viewing audience will play a role in announcing the lineup, but details on that situation are TBD right now. So once more, with feeling, here is the schedule of events for next Tuesday, Feb. 19.

12-1PM ET: Classic Bonnaroo Concert Moments
1-2PM ET: B.L.A.M: Bonnaroo Live Lineup Announcement Megathon hosted by "Weird Al" Yankovic
2-3PM: Surprise Classic Bonnaroo Concert

Watch the Bonnaroo B.L.A.M.