Weather won’t likely prevent the launch, which has an 80 percent go. The forecast includes thick clouds with 10 to 15 mph south winds.
Here's more about the historic Falcon Heavy liftoff:
It is a test flight.
It is essentially three rockets bolted together to make the heavy vehicle.
Falcon Heavy weighs more than 3.1 million pounds (loaded with kerosene and liquid oxygen) and it's about 229 feet tall.
The middle booster will carry Elon Musk’s own Red Tesla Roadster. The Roadster is planned to be near Mars’ orbit in a precession Earth Mars elliptical orbit around the sun. The mission will try to prove that it is possible to put payloads into an orbit intersecting Mars. This would help in the mission to put humans in Mars.
Musk presented this project in 2011, and he planned to roll out the heavy rocket in Southern California in late 2012. He hoped for a launch at some point in 2013 -- it was obviously delayed. The rockets were put in position in pad 39A and tested in December 2017.
Falcon Heavy rockets cost a fraction of the price of the future Space Launch System rockets, which are planned to have more lift and put a space craft further into space, to Jupiter and beyond. They will probably not be ready until the mid-2020s.
Each rocket has nine engines, making it 27 engines in total that need to ignite in tandem.
The two side rockets will jettison from the center rocket two and a half minutes after liftoff. The center booster will continue for a bit longer before engines are shut off.
All three rockets are planned to land back on Earth: two back at the Cape, and the heavier rocket at an Atlantic barge platform called “Of course, I still love you.”
There is a good chance that this launch may fail (but we certainly hope not!).
If successful, there will be more heavy launches during the first half of 2018 from Cape Canaveral.
Central Florida residents, especially those near the coast -- but as far away as metro Orlando -- may hear a sonic boom.