National Weather Service forecasters are warning residents of southeast Minnesota, northeast Iowa and southwest Wisconsin to brace for potentially dangerous weather.
thunderstorms and such. reporter: we met the group in southeastern minnesota and within minutes our lunch break became a lunch rush. we ve got one storm to our northwest that s going to go severe, probably go tornadic. this is the real deal. we already knew it was an explosive day. it was really early, an early show. please, nobody out of the van, we re going to gas and go quick. reporter: our pair of vans raced for the town of northfield, minnesota. look at the rotation. northfield s been hit the last couple of years. they may be about to get hit again. i m always looking at data, i m always looking at doppler radar, watching the sky. we get headed north right toward that storm, and as soon as we approached it look at the rotation! tornado on the ground. bingo, the first tornado drops. tornado, tornado! holy crap, it s right there. reporter: the storm continues