CAPE CANAVERAL, Fla. (AP) - For the second day in a row, foul weather threatens to stall a critical space station delivery for NASA.

CAPE CANAVERAL, Fla. (AP) For the second day in a row, foul weather threatens to stall a critical space station delivery for NASA.

An unmanned Atlas rocket is poised to lift off at 5:33 p.m. Friday from Cape Canaveral, Florida, with 7,400 pounds of supplies for the International Space Station. Thursday's launch attempt was rained out. Forecasters say there's only a 30 percent chance the sky will clear Friday.

The six space station astronauts have gone without U.S. shipments since April. Two private companies contracted by NASA to replenish the orbiting lab are stuck on Earth with grounded rockets. Orbital ATK bought another company's rocket, the Atlas, for this supply mission.

Orbital's last grocery run ended in flames seconds after liftoff last year. SpaceX, the other supplier, suffered a launch failure in June.