Russian cosmonauts, Pavel Vinogradov (back C), Alexander Misurkin (back L), and US astronaut Christopher Cassidy (back R) put on shoe covers over their space suit boots in front of a mock-up of a Soyuz TMA space craft at the cosmonaut training centre in Star City, outside Moscow on March 5, 2013, before taking their pre-flight exam. The return of several other astronauts from the ISS is being delayed due to bad weather.

(Alexander Nemenov/AFP/Getty Images)

MOSCOW -- Bad weather is delaying the return of three astronauts from the International Space Station.

The astronauts were scheduled to land in a Soyuz capsule in central Kazakhstan early Friday morning. But fog and freezing rain prevented Russian rescue helicopters from flying to the touchdown site.

NASA's Kevin Ford and Russians Oleg Novitsky and Yevgeny Tarelkin will stay at the space station for at least another day. They've been in space for nearly five months.

The astronauts had already climbed into their capsule and where waiting to close the hatch when Russian officials called off their departure at the last minute. Their return trip is now set for Saturday, when the weather is expected to be better.

Three other astronauts will remain at the space station.

More on weather.com: Astronaut's Photos from Space

New York

New York City, posted on April 23, 2013. Cmdr. Chris Hadfield tweets: Incredibly clear, before the trees have filled with leaves. (Chris Hadfield/NASA)