The weather forecast looks "promising" for the US shuttle Endeavour's nighttime landing to end its final mission, scheduled for 2:35 am (0635 GMT) on Wednesday, NASA said.
The American shuttle program is readying its final launch, of the Atlantis shuttle, for July 8, before it closes down permanently, ending a 30-year program of human spaceflight and exploration.
"The weather is looking very promising," NASA interim flight director Tony Ceccacci said in an early morning briefing on Tuesday.
The past few days had shown a likelihood of high crosswinds that could have interfered with landing, but those forecasts have improved, he said.
Crosswinds at landing are now expected to be about 10 knots, well below the upper limit of 12 knots for a nighttime landing at Kennedy Space Center in Florida.
"We are very confident that trend is going to stay the same until tomorrow," he said.
The shuttle Endeavour, which first flew to space in 1991, is wrapping up a 16-day mission to the International Space Station, where it installed a two-billion-dollar physics experiment to probe the origins of the universe.
The Endeavour crew includes five American astronauts and one Italian, Roberto Vittori of the European Space Agency.
Explore further: NASA completes successful battery of tests on composite cryotank