The TT race programme today (Wednesday) has been put back by an hour.
The delay was announced by the Race Control Centre in the past few minutes (7.40am).
The reason is understood to be visibility on the mountain section of the course.
It means the Mountain Road is now due to close at 10.30, instead of 9.30am.
That will put back the closure of roads around the rest of the circuit to 11am, and have a knock on effect for the racing programme.