Mark Kelly and the rest of the Endeavour crew are back in Florida preparing for a scheduled launch on Monday, May 16 at 5:56 a.m. Arizona time.

From NASA:

The six astronauts for space shuttle Endeavour's STS-134 mission to the International Space Station now are at NASA's Kennedy Space Center in Florida for their prelaunch preparations. The crew arrived at Kennedy's Shuttle Landing Facility in a shuttle training aircraft at 9 a.m. EDT.

"It's great to be back," said Kelly. "We really appreciate all the hard work by the team that's worked over the last couple of weeks to get shuttle Endeavour ready."

Kelly introduced Endeavour's pilot Greg H. Johnson who commented, "I can't think of a more perfect way to spend my birthday then to come here with my crew a get ready to fly Endeavour next week."

[...]

Shuttle Weather Officer Kathy Winters has forecasted a 70% chance of having favorable weather for Endeavour's liftoff scheduled for 8:56 a.m. Monday.