Weather: Varied. While you can be lucky and get a clear day, it's more likely that from about 9:30am Haleakala will wear it's cloud crown. It can be a huge range of conditions at the top, from wind, chill even snow. The cloud line usually starts at 5000-6000ft. 6000ft is about 21miles into your ride. This cloud and rain line seems to form about 9:30am, so it's likely you will be riding the last third above the clouds.
This is a bucket list route with a wide range of terrain from sea level 3000m finishing at the volcano crater. Featuring switch backs, mixed road surfaces and absolutely beautiful views. Bonus fun descent if you love the down.
A little snippet below