Seeing one of these approaching is pretty intense. In one situation, the clouds hovered ominously on the horizon for awhile, darkening the sun, and a lot of animals were clearly getting the message: I saw foxes, deer, cats, and raccoons hurrying across the road as I went down the highway.
This is what true Texans do. When the tornado siren goes off, we walk outside, study the sky a while, talk to the neighbors, and then if the clouds are really low or really green or really twisting like beaters in cake batter, we head for the storm closet. Otherwise, it's just the weatherman making a mountain out of a molehill.