Poor weather is threatening to put a halt to the bike action today.
The Mountain Road is due to close at 5pm this evening, with the rest of the course shutting at 6pm, for the first Superbike, Superstock and Supersport session.
And the Billown Circuit is due to close for the Pre-TT Classic meeting at 9.10 this morning.
But after the weekend’s bright sunshine, forecasters say heavy rain today may mean standing water on the course.
Neil Young of Ronaldsway Met Office says fog on the hills may also pose problems: