Weather favorable for Wednesday shuttle launch

-- The weather looks favorable for a Wednesday launch of Atlantis, which storms have delayed several times, the shuttle's launch weather officer said Monday.

Thunderstorms could arrive in the area after launch time, which is set for 12:29 p.m. ET Wednesday.

Atlantis was set to lift off August 27 but was delayed while engineers checked the spacecraft for possible damage from a lightning strike. The approach of Tropical Storm Ernesto then forced another delay.

"We do have favorable conditions expected for launch time," said Kathy Winters, the launch weather officer. "We always have a chance of uncertainty."

If the shuttle does not launch Wednesday, then a liftoff later in the week is possible.

The launch will be the first shuttle mission to deliver a major new portion of the international space station since the 2003 crash of Columbia.

CNN's Kate Tobin contributed to this report.