The second of five space shuttle launches NASA plans to conduct this year has been delayed three weeks, to April 5, by Florida’s recent stretch of cold weather.

Space Shuttle Discovery had been slated to lift off March 18 to begin the STS-131 mission to the international space station, but a lengthy cold snap at Kennedy Space Center delayed Discovery’s move to the Vehicle Assembly Building, which in turn delayed the rollout to the launch pad.

STS-131 is the next of four remaining shuttle missions NASA plans to conduct before retiring the fleet from service.