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. Lots of these collisions build up big regions of electric charges to cause a bolt of lightning, which creates the sound waves we hear as thunder. The Thunderstorm Life Cycle Thunderstorms have three stages in their life cycle: The developing stage, the mature stage, and the dissipating stage.
The developing stage of a thunderstorm is marked by a cumulus cloud that is being pushed upward by a rising column of air updraft. The cumulus cloud soon looks like a tower called towering cumulus as the updraft continues to develop. There is little to no rain during this stage but occasional lightning.
The thunderstorm enters the mature stage when the updraft continues to feed the storm, but precipitation begins to fall out of the storm, creating a downdraft a column of air pushing downward. When the downdraft and rain-cooled air spreads out along the ground it forms a gust front, or a line of gusty winds. The mature stage is the most likely time for hail, heavy rain, frequent lightning, strong winds, and tornadoes.
Eventually, a large amount of precipitation is produced and the updraft is overcome by the downdraft beginning the dissipating stage. Get down on your hands and knees and keep your head tucked in. Do not lay flat, because it can give lightning a better chance of strike you.
How far away can you see lightning and hear thunder? Within those distant thunderstorms, the lightning bolts can be seen as much as miles from us, depending on the height of the bolt, the clarity of the air, and our elevation. Thunder, in comparison, has a much shorter range of detection — usually less than 15 miles in a quiet rural setting and under 5 miles in a noisy city environment. Can you tell how far away a storm is? Yes, you can use thunder to tell how far away a storm is.
Next time you see a storm, count the number of seconds between when you see the lightning and hear the thunder. Take the number of seconds and divide by 5 and that will tell you how far away the storm is in miles.
For example: If you counted 10 seconds between the lightning and the thunder, the lightning is 2 miles away! What is fulgurite? Fulgurite is brittle, glassy formations caused by a lightning strike to sandy soil. The lightning heats the soil and fuses the soil particles together surrounding the path of the channel, resulting in a hollow tube-like formation shaped like the section of lightning that formed it. What is a lightning rod? Lightning rods also called conductors are metal rods or similar objects that divert lightning safely to the ground, they can often be seen at the top of tall buildings.
Hail Questions What is hail? Hail is a variety of differently shaped ice balls or lumps. Hail or hailstones are made up of water ice and can be any size; it can be measured anything from five millimetres and two hundred millimeters. Hail is produced during thunderstorms and heavy rains. What is a hailstorm? A hailstorm is a thunderstorm that produces hail. How does hail form? Hail is created when small water droplets are caught in the updraft of a thunderstorm.
These water droplets are lifted higher and higher into the sky until they freeze into ice. Once they become heavy, they will start to fall. If the smaller hailstones get caught in the updraft again, they will get more water on them and get lifted higher in the sky and get bigger. Once they get lifted again, they freeze and fall. This happens over and over again until the hailstone is too heavy and then falls to the ground. How does hail fall to the ground?
Hail falls when it becomes heavy enough to overcome the strength of the updraft and is pulled by gravity towards the earth. How it falls is dependent on what is going on inside the thunderstorm. Hailstones bump into other raindrops and other hailstones inside the thunderstorm, and this bumping slows down their fall. Drag and friction also slow their fall, so it is a complicated question! If the winds are strong enough, they can even blow hail so that it falls at an angle. This would explain why the screens on one side of a house can be shredded by hail and the rest are unharmed!
How fast does hail fall? We really only have estimates about the speed hail falls. However, the hailstone is not likely to reach terminal velocity due to friction, collisions with other hailstones or raindrops, wind, the viscosity of the wind, and melting. Also, the formula to calculate terminal velocity is based on the assumption that you are dealing with a perfect sphere. Hail is generally not a perfect sphere! What areas have the most hail?
Though Florida has the most thunderstorms, Nebraska, Colorado, and Wyoming usually have the most hail storms. The reason why this area gets so much hail is that the freezing levels the area of the atmosphere at 32 degrees or less in the high plains are much closer to the ground than they are at sea level, where hail has plenty of time to melt before reaching the ground.
Other parts of the world that have damaging hailstorms include China, Russia, India and northern Italy. Does hail fall in paths? When viewed from the air, it is evident that hail falls in paths known as hail swaths. They can range in size from a few acres to an area 10 miles wide and miles long. Piles of hail in hail swaths have been so deep, a snow plow was required to remove them, and occasionally, hail drifts have been reported.
How large can hail get? Hail is usually pea-sized to marble-sized, but big thunderstorms can produce big hail. The largest hailstone recovered in the U. It weighed 1 lb 15 oz. What types of thunderstorms produce large hail? Supercell thunderstorms have sustained updrafts that support large hail formation by repeatedly lifting the hailstones into the very cold air at the top of the thunderstorm cloud.
In general, hail 2 inches 5 cm or larger in diameter is associated with supercells. Non-supercell storms are capable of producing golf ball size hail.
How is hail measured? Hail size is estimated by comparing it to a known object. Most hail storms are made up of a mix of sizes, and only the very largest hail stones pose serious risk to people caught in the open. Can meteorologists detect when hail is going to form in a thunderstorm? Meteorologists can predict when thunderstorms are going to happen and can detect hailstorms and hail occurring. This can be done through weather radar imagery and satellites used especially for predicting weather and weather changes.
When the hail is created and are larger than normal or average size, then they will fall at greater speeds. What kind of damage does hail cause? Hail can actually cause a lot of damage especially to cars and vehicles, aircrafts, buildings, crops and animals. More often than not, it is the roofs which take full effects of the hailstorm damage and can cause cracks in buildings and leaks in the roof.
Hailstorms are very troublesome to drivers of vehicles because they can reign down on vehicles and cause a lot of damage to roofs, hoods and even come crashing through sunroofs. Windshields are often the target of hailstones and can crack or shatter them completely.
Why does the sky look green during some hail storms? One theory is that large amounts of water and ice in a severe thunderstorm will scatter green light during the strong updrafts that occur in severe storms. Damaging Wind Questions What causes the wind to blow? Some parts of the Earth receive direct rays from the sun all year and are always warm. Other places receive indirect rays, so the climate is colder. Warm air, which weighs less than cold air, rises.
Then cool air moves in and replaces the rising warm air. This movement of air is what makes the wind blow. What are damaging winds?
Strong thunderstorm winds can come from a number of different processes. Most thunderstorm winds that cause damage at the ground are a result of outflow generated by a thunderstorm downdraft.
Damaging winds are classified as those exceeding mph. What are straight-line winds? Straight-line wind is a term used to define any thunderstorm wind that is not associated with rotation, and is used mainly to differentiate from tornadic winds.
What is a downdraft? A downdraft is a small-scale column of air that rapidly sinks toward the ground. If shutters are not available, close window blinds, shades or curtains. If a thunderstorm is likely in your area, postpone outdoor activities.
Be Safe During a Thunderstorm Get inside a home, building, or hard top automobile not a convertible. Do not touch anything metal. Although you may be injured if lightning strikes your car, you are much safer inside a vehicle than outside. Remember, rubber-soled shoes and rubber tires provide NO protection from lightning. However, the steel frame of a hard-topped vehicle provides increased protection if you are not touching metal. Avoid showering or bathing.
Plumbing and bathroom fixtures can conduct electricity. Use a corded telephone only for emergencies. Cordless and cellular telephones are safe to use. Unplug appliances and other electrical items such as computers and turn off air conditioners. Power surges from lightning can cause serious damage. Be Safe Outdoors If you are outside during a thunderstorm, avoid: Natural lightning rods such as a tall, isolated tree in an open area.
Hilltops, open fields, the beach or a boat on the water. Isolated sheds or other small structures in open areas.
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