From his twitter feed:
MikeyWelsh71Mikey Welsh
dreamt i died in chicago next weekend (heart attack in my sleep). need to write my will today. 26 Sep
Mikey Welsh was found dead in a hotel room in Chicago, at 2.50 pm on Saturday the 8th of October. Mikey was the bassist with Weezer, and played on such hits as hash pipe and island in the sun. In later years, he started working as an artist and seemed pretty talented from what I’ve seen of his work. The only reason I’m posting it though, is that he seems to have predicted his own death on twitter! Weird….
No More Workhorse 
That’s sad. I have to say, I have a big soft spot for Weezer but I never got past the debut album (The Blue Album) and second album Pinkerton (both great pop/rock records in my opinion). I think Mikey joined after Pinkerton. Sad stuff, and odd that he predicted it on the Tweet Box?
I’m wondering does everything you say in twitter come true? Odd in the extreme that one. It’s sad to see anyone die, but I can’t say I’ve heard of him before. He looked a pretty good artist actually. Quite like his stuff.
I never got into Weezer, I tried their early albums, but they were not for me. A little bit too poppy really…