Severe weather is any weather that is destructive. The term is usually used to refer to: thunderstorms tornados tropical storms snowstorms/blizzards ice storms drought

Small area storms formed by the strong upward movement of warm, moist airSmall area storms formed by the strong upward movement of warm, moist air Usually occur ahead of a cold front as the colder, denser air shoves the warmer air upwardUsually occur ahead of a cold front as the colder, denser air shoves the warmer air upward This movement of air forms the cumulonimbus clouds that produce thunderstormsThis movement of air forms the cumulonimbus clouds that produce thunderstorms These storms are accompanied by heavy rain, thunder, lightning, sometimes hail, and can also produce tornadoesThese storms are accompanied by heavy rain, thunder, lightning, sometimes hail, and can also produce tornadoes

 All thunderstorms produce lightning  Lightning is the discharge of huge amounts of static electricity (think of walking across a carpet in your socks and then touching something-ZAP)  Thunder is the result of the air quickly expanding from the heat of the lightning bolt  You cannot have lightning without thunder!!

Thunderstorm formations – Thunderstorm formations – Form SEVERE storms and tornadoes! THIS IS ONE BIG STORM SYSTEM!

very powerful thunderstorms  Form from very powerful thunderstorms (cumulonimbus clouds) funnel  These are funnel shaped columns of spiraling winds that extend down to the ground from the base of a cloud  The winds move into a tornado (low pressure), and can reach a maximum of 318 mph!  Spin COUNTER CLOCKWISE (like a hurricane)  The actual funnel is made by water droplets (clouds) and dust

A blizzard is a severe winter condition with low temperatures, strong winds, and heavy blowing snow. An ice storm is a type of winter storm with freezing rain.

A drought is an extended period of months or years when a region receives consistently little or no precipitation.precipitation

WILDFIRES are often the result of DROUGHT

A tropical storm is the overall name for a storm which is spinning. They form when warm water heats the air causing it to rise really quickly, then it gets pushed aside as it cools. This pushing causes the clouds to spin.. Different names for tropical storms: hurricane typhoon severe tropical cyclone tropical cyclone

Hurricanes are tropical storms where the winds get faster than 118 km/h (73 mph). The storms have a central area of calm known as the "eye", which is the funnel through which the warm air rises. Why are we seeing more of these destructive storms?

El Niño is an abnormal warming of surface ocean waters in the eastern tropical Pacific.

Strong winds blow from the east along the equator, pushing warm water into the Pacific Ocean

 The different water temperatures of these areas effects the types of weather these two regions experience.  In the east the cool water cools the air above it, and the air becomes too dense to rise to produce clouds and rain.  In the western Pacific the air is heated by the water below it, increasing the buoyancy of the lower atmosphere thus increasing the likelihood of rain.  This is why heavy rain storms are typical near Indonesia while Peru is relatively dry.

An El Nino condition results from weakened trade winds in the western Pacific Ocean near Indonesia, allowing piled-up warm water to flow toward South America.

 This flattens out the sea level, builds up warm surface water off the coast of South America, and increases the temperature of the water in the eastern Pacific.

 What happens to the ocean also affects the atmosphere.  Tropical thunderstorms are fueled by hot, humid air over the oceans.  The hotter the air, the stronger and bigger the thunderstorms.  As the Pacific's warmest water spreads eastward, the biggest thunderstorms move with it.

 The clouds and rainstorms associated with warm ocean waters also shift toward the east.  So, rains which normally would fall over the tropical rain forests of Indonesia start falling over the deserts of Peru, causing forest fires and drought in the western Pacific and flooding in South America.

 The Earth's atmosphere responds to the heating of El Niño by producing patterns of high and low pressure which can have a profound impact on weather far away from the equatorial Pacific.  For instance, higher temperatures in western Canada and the upper plains of the United States, colder temperatures in the southern United States. The east coast of southern Africa often experiences drought during El Nino.

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