The official lineup for this year’s Outside Lands Music Festival is arrives April 16 but thanks to leaks from organizers and rumors online, we have good idea about who will perform.

UPDATE, April 16: The Outside Lands 2013 lineup was released today, the rumors held true. Paul McCartney, Red Hot Chili Peppers and Phoenix will headline along with the act below. Check out the complete lineup.

UPDATE, April 14: All eyes are on Coachella as the Southern California festival wraps up its first weekend in Indio, but it’s also been a busy weekend for Outside Lands. Festival organizers leaked more clues on Instagram, including The National (first reported here as a legit rumor on April 2), Willie Nelson, the Men, Young the Giant, Jurassic 5 and Yeasayer. Here’s what they’ve leaked to date and rumors we think are true:

Willie Nelson

The National

Jurassic 5

Yeasayer

Young the Giant

The Men (pictured above)

Grizzly Bear

The Tallest Man on Earth

Chromatics

Wavves

Zedd

Twenty One Pilots

Rumors we think are true:

Paul McCartney

Phoenix

Red Hot Chili Peppers

The official lineup announcement arrives Tuesday. We’ll let you know as soon as it’s released.

UPDATE, April 12: More lineup clues have arrived via the Outside Lands Instagram account, confirming that Grizzly Bear, The Tallest Man on Earth, Chromatics, Wavves, Zedd and Twenty One Pilots will perform at the festival this year. There’s still no word the status of Paul McCartney, Red Hot Chili Peppers and Phoenix as potential headliners. The three acts since been removed from the Last.fm page we wrote about last month. We will know all of the details April 16.

UPDATE, April 9: There’s more news form Outside Land today via Twitter. This time it’s an announcement that an announcement for the lineup will arrive in a week: “ranger dave will announce the 2013 outside lands artist lineup on tuesday, april 16th. only 7 days until lift off.” More details soon. Who would you like to see at the festival?

UPDATE, April 2: We thought for a moment that the Outside Lands 2013 lineup would be revealed today after a teaser tweet from @sfoutsidelands just after 9:45am: “ranger dave will have something to tell you in a little more than 2 hours.” But it was followed by a tweet at noon, “ranger dave will put eager beaver 3-day tickets on sale thursday & for the first time special 3-day tickets as well. and so it begins.”

The lineup was released April 17 last year, so we probably still  have some time before the official announcement. Meanwhile, the rumor mill continues to churn. Last.fm is offering more clues with the link we posted on March 12, which has since been updated with an image of the Red Hot Chili Peppers, Phoenix and the National next to Paul McCartney. Stay close for more news soon.

ORIGINAL POST: Online music recommendation service Last.fm currently lists Sir Paul McCartney as a confirmed performer. Whether or not this is some sort of typo or mistake remains unconfirmed, but a heavy dose of Beatles hits would be a welcome addition to the annual outdoor music festival held at Golden Gate Park.

Other potential artists we think are likely to make appearances in San Francisco for the festival on August 9-11 include the recently reunited Postal Service (also at Coachella this year), indie favorites Vampire Weekend (back on the road with a new album), 2012 Mercury prize winner Alt-J, 2010 Mercury prize winning trio the XX and Grammy award winning folk rock band The Lumineers. Willie Nelson, Steve Martin and Hall & Oates—all performing in LA on days surrounding Outside Lands—could also make their first appearance at the festival.

We’re still keeping our fingers crossed for the outside chance that Prince will make an appearance. The official lineup announcement from organizers should arrive within the next few weeks. Stay tuned…

Check out highlights from Outside Lands 2012 and relive Outside Lands 2012 with our photo gallery.