After a 125cc race which was run mostly in the dry, being red-flagged 6 laps from the end after it started to rain, the rain has begun in earnest. The start of the 250 race has been delayed due to high winds and very heavy rain, and no word yet on how this will affect the rest of the schedule.
Dorna have just announced that the 250 race will now be run at 4:30pm local time, after the MotoGP race. That presumes, of course, that the MotoGP race can take place at a track which is currently being lashed by the remnants of hurricane Ike.
Spanish TV just interviewed a member of Race Direction, and he said that they will be trying to dry the more dangerous parts of the track mechanically, and hope to run the MotoGP race at 3pm local time without problems. The track may well still be wet, but it shouldn't be completely inundated. The weather radar shows that most of the rain is moving to the north of Indianapolis, sparing the track of the worst of the weather.
We will keep you updated as soon as we know more.