(AP) -- The weather isn't cutting NASA any breaks, not even for the last space shuttle launch.
Forecasters say there's a 70 percent chance that rain or thunderstorms will prevent Atlantis from flying Friday. That's worse than before. The weather forecast improves slightly over the weekend.
Mission managers were reviewing all the flight details one last time Wednesday. Despite the poor weather outlook, they were expected to give a "go" for launch.
This will be the 135th and final mission of NASA's 30-year shuttle program. Four astronauts will ride Atlantis one last time on a supply run to the International Space Station.
As many as 1 million people are expected to jam Cape Canaveral for the historic liftoff. Launch time is 11:26 a.m.
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