how much mph does all the violent tornadoes have
Usually a weak tornado will last for just a few minutes and have wind speeds of 100 mph or less. Some tornadoes intensify further and become strong or violent. Strong tornadoes last for twenty minutes or more and may have winds of up to 200 mph, while violent tornadoes can last for more than an hour with winds between 200 and 300 mph! These violent tornadoes are rare in occurrence.