An average of 27 tornadoes occur in the State per year. May. There were no tornado fatalities last year, but a number of people were injured. Most tornadoes produce rotating winds of 50 to 120 mph. They move at speeds of about 30 to 40 mph. There have been tornadoes recorded in Illinois with winds of 200 mph moving at up to 70 mph.
Severe thunderstorms can also produce very damaging winds.
They can cause significant structural damage to buildings, especially weaker structures such as barns and outbuildings. Thunderstorms may be accompanied by large hail and dangerous lightning. Hail rarely causes injuries , but it can cause millions of dollars in damages to crops, vehicles, and buildings. Lightning poses a significant risk to citizens. Flooding is a significant severe weather hazard in Illinois.