Large landmasses can heat up during the day and cause free convection, resulting in thunderstorms. Above the oceans, thunderstorms are more frequent near coastlines than in areas far from a coast; this reflects the sharp contrasts in air masses that occur along coastlines.
Most of the 2, or so thunderstorms occurring at any time in the world are located within the Intertropical Convergence Zone ITCZ , especially in the afternoon. Abundant tropical moisture, strong surface heating, and vigorous trade-wind convergence are responsible.
Note the high density of thunderstorms in central Africa, attributable to the ITCZ and a large continent. North America exhibits frequent thunderstorms, reflecting a supply of warm, moist air from the Gulf of Mexico , abundant solar heating of the land, and the frequent passages of weather fronts.
Europe commonly lacks much contrast between air masses, as the westerlies push a continual parade of mP air masses across the continent. Also, the mountains mostly trend east-west, parallel to the westerlies, minimizing the interaction between very hot and very cold air masses.
As a result, Europe has fewer thunderstorms than might be expected, considering the frequency of frontal passages and rainy days. Polar regions, including Antarctica , are too cold to have moisture sufficient for the condensation and deposition required to support thunderstorms, even in the summer. Both poles are among the places least likely to experience thunderstorms and lightning. These maps show the variations in lightning thunderstorms between summer and winter.
The top map is for winter in the Northern Hemisphere and summer in the Southern Hemisphere. The bottom map shows the opposite northern summer; southern winter. Examine these maps and compare the number of thunderstorms in summer versus winter for different regions. Finally, you need lift. This can form from fronts, sea breezes or mountains.
When are thunderstorms most likely to occur? Thunderstorms can occur year-round and at all hours. But they are most likely to happen in the spring and summer months and during the afternoon and evening hours. How many thunderstorms are there every day? It is estimated that there are around 1, thunderstorms that occur across our planet every day. Are thunderstorms dangerous? 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. Mesocyclone, D. Tail cloud, E. Wall cloud, F. A watch can cover parts of a state or several states. Begin typing your search term above and press enter to search.
Press ESC to cancel. Useful tips. Esther Fleming March 29, Worldwide, there are an estimated 16 million thunderstorms each year, and at any given moment, there are roughly 2, thunderstorms in progress.
There are about , thunderstorms each year in the U. When are thunderstorms most likely? Thunderstorms are most likely in the spring and summer months and during the afternoon and evening hours, but they can occur year-round and at all hours. Along the Gulf Coast and across the southeastern and western states, most thunderstorms occur during the afternoon.
Thunderstorms frequently occur in the late afternoon and at night in the Plains states. What kinds of damage can thunderstorms cause? Many hazardous weather events are associated with thunderstorms. Under the right conditions, rainfall from thunderstorms causes flash flooding, killing more people each year than hurricanes, tornadoes or lightning. Lightning is responsible for many fires around the world each year, and causes fatalities.
Hail up to the size of softballs damages cars and windows, and kills livestock caught out in the open.
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