Severe weather is any dangerous or severe weather(obviously) with the potential to cause damage. There are many types of severe weather, but right now I'll just be talking about the most severe in my opinion.
Tornadoes are moving destructive funnels (or cones ) of wind coming out of a large storm, most of the time a thunderstorm. In order for a tornado to form, you need warm air and cool air to meet, creating an off-balance in the force-I mean, atmosphere. Also, there needs to be low air pressure, as there is for every type of storm. A little fun fact, tornadoes are called "funnel clouds" until they hit the ground and make the "transformation" into tornadoes. The "Tri-State Tornado" was debatably one of the worst if not the worst tornado in the history of the United States. It happened on March 18, 1985, killed 695 people, and injured over 2,000. It went through Missouri, Illinois, and Indiana. (Not Indiana Jones though, that's someone else.)If you happen to see a tornado, you should probably not go out and say hi, you should find a room,(preferably underground, like a basement)with no windows and curl into a ball while covering your head so flying debris don't hit it. The average number of tornadoes each year is 1,179. The average number of people killed is 227 and the average economic damage is 1,087,575,000 dollars.
A thunderstorm is a large storm with thunder, lightning, and lots and lots of rain. Thunderstorms are formed when cumulonimbus(clouds known for causing thunderstorms) clouds get heavy with water and then the water falls to the ground as rain. The lightning part of it is formed when positively charged ice particles,(because it's very cold higher up) and negatively charged ice particles in the cloud get large enough and create small discharges of electricity in the cloud. Now, you might be wondering, how does it strike the ground? Well, the positively charged particles on the ground get attracted to the negatively charged particles in the cloud and create a not-so-little discharge of electricity. In the case of a thunderstorm, you shouldn't go outside and if you do you shouldn't stand by anything that might fall on you. One of the worst thunderstorms(in terms of cost) was on May 5, 1995 in Fort Worth, Texas and cost over 2 billion in repairs. Lightning from thunderstorms are responsible for 23 deaths, 125 injuries, and over 23 million in property damage.
A blizzard is a severe snow storm that usually happens over the course of 3 hours. For a blizzard to form, there have to be temperatures below freezing(32 degrees Fahrenheit)clouds, and lots of warm air moving over cold air. Blizzards are basically snowstorms with strong winds.