Inside the biggest tornado hunt in history

It's mid-afternoon and I am sitting with a group of researchers in a dusty parking lot in north-west Nebraska. There's a growing buzz of excitement as equipment is checked one last time and then we set off. Finally, we are about to catch a glimpse of what we have been hunting for weeks: a tornado.

I have joined the biggest tornado hunt in history. The two-year, $12 million project, called Verification of the Origin of Rotation in Tornadoes Experiment, or VORTEX2, began on 10 May with the aim of recording, for the first time, the entire life cycle of a tornado. A team of more than 100 researchers has assembled an unprecedented variety of instruments which it hopes will force tornadoes to give up their secrets. Until today, though, things had not gone to plan.

Over the last three-and-a-half weeks, this nomadic tribe has travelled almost 10,000 kilometres, through six states of America's Midwest, searching for signs of supercells, the huge thunderstorms that spawn tornadoes. They'd had no luck, though. Each time the 40 vehicle convoy reached a promising area, either nothing developed or they arrived just in time to watch the storm fade away.

This is in stark contrast to 2008 - one of the most violent years on record, when 1691 tornadoes killed over 120 people. Tornado reports for 2009 are down 75 per cent, and the team is getting desperate. Morale-boosting pep talks, practice instrument deployments plus the odd hour of relaxing down time have helped keep the researchers ready for their big moment. And now it has arrived.