Chilly Weather, Low Clouds Sweep Into KSC

NASA definitely would be "no-go" if shuttle Discovery had been slated to launch today on its 39th and final flight.

Something akin to a cold front swept into the Kennedy Space Center area this afternoon, bringing low cloud ceilings and chilly winds along with it.

NASA launch commit criteria prohibit launching if cloud decks over the shuttle landing facility dip below 5,000 feet. Mission commanders must be able to see the runway in the unlikely event that an emergency landing is requiired.

Cloud decks at the launch pad also must be above 4,000 feet so range safety officers can track the shuttle during the critical early parts of a shuttle flight -- the time when the shuttle presents the most danger to people at and around the space center.

The official forecast for launch on Thursday calls for an 80 percent chance conditions will be acceptable for an on-time liftoff at 4:50 p.m. Check it out HERE