What are the three major types of severe weather? describe at least two characteristics of each type.

High winds-  wind speeds as low as 23 knots (43 km/h) may lead to power outages when tree branches fall and disrupt power lines. Once wind exceed 135 knots (250 km/h) within strong tropical cyclones and tornadoes, homes  completely collapse,  and significant damage is done to larger buildings. Total disruption occurs once wind exceeds 175 knots (324 km/h)

Tornado- Typically look like a narrow funnel reaching from the clouds to the ground. Their wind speed goes from 65 to 250 miles per hour.

wildfires- Their behavior depend on factors such as fuel type, moisture content in the fuel humidity, windspeed, topographic and geographic location. 
They have a rapid forward rate of spread (FROS) When fueled by dense uninterrupted vegetation, particularly in wooded areas with canopies.

The severe and unstable conditions which disturbs the normal weather system or conditions are many, but some of them are as follows;

Explanation:

Blizzards:

"An extreme weather condition in which we face the high speed wind in combination with heavy snow."

As for any blizzard has the normal wind speed of about 40 mph, and the visibility range reduces to less then 500 ft.

    2.Thunderstorm:

Inside a thunderstorm there is heavy rainfall, high speed winds, along with some lighting which makes it even more dangerous for any person to be in such a region where thunderstorm happens to be.

As thunderstorms are produced from the high density, and tall clouds which are involved in making thunderstorms, such clouds are called as cumulonimbus clouds.Moist and unstable air, along with lift forms the thunderstorm in general.

 3.Tornado

The weather instability created due to mixing of moist warm air,with cold and dry air. Which then take the shape of spinning effect in the lower atmosphere forms, due to change in wind speed and direction.

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