Front to weaken; Thu. weather still 70% "no go"

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The front that spawned tornados killing nearly 50 people in the Southeast will weaken as it passes over Cape Canaveral near the time of Atlantis' 2:45 p.m. EST launch on Thursday.

"For our area it's going lose a lot of its energy," shuttle weather officer Kathy Winters said.

A 5 percent chance of severe weather exists during launch, she added. The weather threat likely will come from thunderstorms rather than the frontal boundary.

The Air Force weather forecast predicts a 70 percent chance of unfavorable weather at launch time Thursday. The forecast was 60 percent unfavorable on Tuesday.

The chance of unfavorable weather for Friday also has increased to 40 percent.

"It'll take a couple of days to get the weather out of the area," said Winters.

NASA managers plan to roll back the rotating service structure today at 6 p.m. Mission managers will meet at 4:45 a.m. Thursday to decide whether to proceed with filling fuel tanks and proceeding toward launch.

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Click for STS-122 fact sheet.