"Mike Davis just informed us that it will be at least until 2 p.m. before players possibly could get out to the practice range to warm up for a resumption of play today. Heavy rain is still expected over the next 45 minutes, but the good news is there's a window this afternoon when golf should be able to resume. The hope is that the morning wave of 78 competitors can complete round one today, with the afternoon wave, which includes Phil Mickelson, completing the first round on Friday.
Once the rain does stop, Jim Hyler, the chairman of the Championship Committee, said it would take 30 minutes or so to get the course back into playing condition."
Running updates can be found here.