Discovery rained out Thursday. Photo Credit/NASA TV

Stormy weather across Florida on Thursday prompted NASA to postpone efforts to launch the shuttle Discovery on her 39th and final flight, an 11-day mission to the International Space Station.

The space agency will try again on Friday.

The forecast for the planned lift off on Thursday at 3:29 p.m., EDT,  included an 80 percent chance of flight rule violations from rain and low cloud ceilings associated with a passing cold front.

Friday’s launch attempt is scheduled for 3:03 p.m., EDT. The forecast reverses behind the front, with a 70 percent chance of favorable conditions. However, strong northerly winds could be a factor, said Pete Nicolenko, NASA’s assistant launch director.

Rain, clouds invade Florida. Photo Credit/NASA TV

Mission managers made their scrub decision early Thursday, before the launch teams started to fuel Discovery. The early decision preserved the possibility of making launch attempts on Saturday and Sunday as well as Friday.

Discovery’s launch period expires after Sunday because of high solar temperatures on the orbital plane of the International Space Station. The temperatures will exceed shuttle limits. The next launch period extends from Dec. 1 to 5.

Discovery’s six astronauts are trained to equip the space station with a storage module, external spare parts and Robonaut 2, an experimental humanoid. Two spacewalks are planned as well