Space shuttle Discovery (search) will have to wait a day to complete the last leg of its trip home.

Discovery had been expected to arrive at Kennedy Space Center (search) in Florida on Saturday after riding piggyback atop a jumbo jet across the country, but NASA delayed the trip for a day because of weather concerns, said Bruce Buckingham, a spokesman with the space agency.

The jet took off Friday from California and arrived at Louisana's Barksdale Air Force, one of several refueling stops. Shuttle managers were to meet Sunday morning to reassess the flight plan, Buckingham said.

An Air Force KC-135 (search) has flown ahead of the shuttle and the modified Boeing 747 to monitor weather along the route. The expected cost of the trip: at least $1 million.

Discovery and its seven-member crew touched down Aug. 9 in California's Edwards Air Force Base after low clouds and lightning prevented the shuttle from returning to Florida during four earlier opportunities.

After landing, Discovery underwent maintenance inside a steel structure on the base two hours north of Los Angeles. Crews purged the shuttle of hazardous substances, removed fuel from the on-board tanks and attached a 10,000-pound aluminum tail cone to eliminate drag during flight.

Discovery's homecoming has been tempered by uncertainties about the shuttle program's future. The same foam problems that doomed the shuttle Columbia 2 1/2 years ago showed up during Discovery's liftoff, prompting NASA to ground all shuttle flights until 2006 so engineers could find a solution.

A chunk of foam insulation broke off Discovery's redesigned external fuel tank during liftoff on July 26, but unlike in Columbia's case, the foam missed hitting Discovery. Columbia disintegrated over Texas, killing all seven astronauts on board.

NASA ground crews who inspected Discovery after its return from orbit found little damage to its exterior.