FARGO - Around 1300 tornadoes, on average, touch down somewhere in the United States per year. Around 60 deaths per year, on average, are caused by these 1300 tornadoes, meaning there is fewer than one death for every 20 tornadoes. The most common EF0 (wind speed 65-85 mph) and EF1 (wind speed 86-110 mph) tornadoes rarely result in fatalities.
About half the tornado deaths, on average, are caused by the rarest EF4 (wind speeds 166-200 mph) and EF5 (wind speeds greater than 200 mph) tornadoes, which make up about one per cent of all tornadoes. These tornadoes are capable of leveling structures, and even small towns. These most powerful tornadoes are the ones usually responsible for large numbers of fatalities at once. The 1957 north Fargo tornado was in this category. The EF rating is determined by surveying the type of damage caused by a tornado. A tornado is rated by its highest rating, even though it is not at that strength over its entire course.