EXCLUSIVE

Harvey Weinstein's private flight to an Arizona rehab facility was diverted at the last minute, and he touched down in a different city than originally planned ... TMZ has learned.

Weinstein is now getting treatment somewhere in the Scottsdale area ... according to well-connected sources. As we reported, the private jet that took off from L.A. Wednesday evening was scheduled to touch down in Wickenburg, AZ ... near The Meadows rehab center.