Complex interactions between the updraft and the surrounding winds, both at storm level and near the surface, may cause the updraft to begin rotating and a tornado is born. A tornado is a violently rotating column of air in contact with the ground with speeds of 60-300 mph. It is only visible due to water droplets mixed with dust and debris. The radar only detects precipitation and light rain in the center of heavy rain indicates tornado potential. The most common direction of a tornado path is from the Southwest to the Northeast but they can come from any direction.
Tornadoes are most likely to occur during the afternoon and evening.
The most violent storms occur in March, April, May, November and December. All buildings have at lease one undesirable structural feature relating to the effects of a tornado. C. Utilize interior spaces with short spans. D. Keep occupants as far away as possible from entrances. E. Avoid areas expected to become wind tunnels.