What a bummer. A phenomenal musician (what else could you be in the Dregs?) and a genuine nice guy.
I had the pleasure of hanging out with the Dregs after a gig in Philly in 1992 and even got a guitar lesson from Steve Morse (long, long story I'll tell it some day and try to get pictures on here-can you transfer photos onto a computer?).
Anyway, what a guy and what a player-one of the best in the biz. Rest well my friend.

From AntiMusic.com:

The Deep Purple Appreciation Society has announced that keyboardist T Lavitz has passed away at age 54 in his sleep. Over the years, Lavitz was a member of Dixie Dregs (with current Deep Purple guitarist Steve Morse), as well as Jazz Is Dead, The Bluesbusters and Jefferson Starship.

The keyboardist was asked to join jazz fusion band Dixie Dregs in 1979, when he was still a senior at the University of Miami. Although the band broke up in 1983, he joined the group for its many reunions, and also worked with his old buddy Morse on the guitarist's solo albums.

Lavitz also released several solo albums, including 2009's Electric, in addition to appearing as a guest on a number of other artists' releases. The keyboardist worked with Robby Krieger, Pat Benatar, Nils Lofgren, Widespread Panic, his old buddy Morse and many others.

In addition to his many other accomplishments, I enjoyed his "From The West" album quite a bit. Really got lost in the song "Tree People". RIP.