msnbc.com's Alan Boyle reports from CAPE CANAVERAL, Fla.:

Despite the looming threat of stormy weather, NASA fueled up Atlantis on Friday for the final launch of the 30-year space shuttle program.

The three-hour process of filling the shuttle's external fuel tank was completed just before 5 a.m. ET, marking the day's first step toward the last liftoff at 11:26 a.m. ET. After this resupply flight to the International Space Station, NASA is due to prepare Atlantis for museum display, as it is already doing with the fleet's other two spaceships, Discovery and Endeavour.

No technical issues stood in the way of Friday's scheduled liftoff, but it was by no means a sure thing. Forecasters put the chances of acceptable weather for launch at 30 percent, after a day that saw lightning and torrents of rain. Continue reading.

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