<human>:  What's the difference between a hurricane and a tornado?
<bot>: The main difference between a hurricane and a tornado is the size and speed of the system. A hurricane is a large rotating storm system typically hundreds of miles in diameter and with wind speeds that can exceed 155 mph. A tornado, on the other hand, is a rapidly rotating column of air that is usually in contact with both the surface of the earth and a cumulonimbus cloud. Tornados are typically smaller than hurricanes and have lower wind speeds, usually topping out around 110 mph or so.