Weather a threat to shuttle launch

CAPE CANAVERAL, Fla., June 30 (UPI) -- The countdown for Saturday's launch of space shuttle Discovery is on schedule but the U.S. space agency is weary about the weather over Florida.

There appeared to be no major technical or safety issues holding up the launch.

Friday was the second of a three-day countdown to the scheduled launch Saturday afternoon but the National Aeronautics and Space Administration was worried about likely thunderstorms that could indefinitely delay the launch.

If everything goes according to schedule, the 12-day mission will be the 115th shuttle flight and the 18th U.S. flight to the International Space Station. The crew will test new equipment and procedures to improve shuttle safety, deliver supplies and make repairs to the space station.

Mission Management Team Chairman John Shannon said that other than "some questionable weather, we have no constraints for launch."

Another official said the cryogenic fuel loading was on hold due to a weather advisory but added the facility has enough hold time remaining in the countdown.