The Atlas Air flight departed Miami for Houston at 11:30 a.m. Eastern time. Two hours later the crew contacted Houston controllers and began their descent. ATC provided radar vectors to avoid an area of rain and then, six minutes later, cleared Flight 3591 to descend to 3,000 feet. At 12:39 local time when the jet had descended to 6,000 feet, controllers lost radar contact. There was no distress call.