A watch can cover parts of a state or several states. Warnings mean there is a serious threat to life and property to those in the path of the storm. ACT now to find safe shelter! A warning can cover parts of counties or several counties in the path of danger. How does a thunderstorm form? As the air rises, it transfers heat from the surface of the earth to the upper levels of the atmosphere the process of convection.
The water vapor it contains begins to cool, releases the heat, condenses and forms a cloud. The cloud eventually grows upward into areas where the temperature is below freezing. As a storm rises into freezing air, different types of ice particles can be created from freezing liquid drops.
The ice particles can grow by condensing vapor like frost and by collecting smaller liquid drops that haven't frozen yet a state called "supercooled". When two ice particles collide, they usually bounce off each other, but one particle can rip off a little bit of ice from the other one and grab some electric charge. All thunderstorms begin with air rising into the atmosphere to form a convection cell, but the air can be lifted in different ways.
Another way to classify thunderstorms is by the location where they form and the reason that air rises. The pictures below describe three different ways that lifting of air can begin: due to a mountain or hillside, within an air mass, or at a storm front.
Orographic thunderstorms are caused by air that is forced up by a mountain or hillside. Air mass thunderstorms are the result of localized convection in an unstable air mass.
Yes, despite their small size, all thunderstorms are dangerous. Every thunderstorm produces lightning, which kills more people each year than tornadoes. What is lightning? Lightning is a bright flash of electricity produced by a thunderstorm.
All thunderstorms produce lightning and are very dangerous. If you hear the sound of thunder, then you are in danger from lightning. Lightning kills and injures more people each year than hurricanes or tornadoes; between 75 to people. What causes lightning? Lightning is an electric current. Within a thundercloud way up in the sky, many small bits of ice frozen raindrops bump into each other as they move around in the air.
All of those collisions create an electric charge. After a while, the whole cloud fills up with electrical charges. The positive charges or protons form at the top of the cloud and the negative charges or electrons form at the bottom of the cloud. Since opposites attract, that causes a positive charge to build up on the ground beneath the cloud. The grounds electrical charge concentrates around anything that sticks up, such as mountains, people, or single trees. The charge coming up from these points eventually connects with a charge reaching down from the clouds and - zap - lightning strikes!
Have you ever rubbed your feet across carpet and then touched a metal door handle? If so, then you know that you can get shocked! Lightning works in the same way. Click Here to see where lightning is currently striking across the U.
What causes thunder? Thunder is caused by lightning. When a lightning bolt travels from the cloud to the ground it actually opens up a little hole in the air, called a channel.
Once then light is gone the air collapses back in and creates a sound wave that we hear as thunder. The reason we see lightning before we hear thunder is because light travels faster than sound!
How do you know if lightning is nearby? If you see dark clouds, then lightning could be present, but the best thing you can do is to listen for thunder. As the air lifts higher and higher, it causes a storm cloud to grow taller and taller. Thunderstorm clouds can rise up to 10 miles into the air! In a big thunderstorm cloud, there are now strong upward winds and downward winds happening at the same time.
These are called updrafts and downdrafts.
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