do tornados only happen in north america, and if not what other country has as ba d of a torado season as our?
448654
Tornadoes can happen anywhere, anytime, at any place if the conditions are right.
928319
I've never heard it been used in weather but some most-known related slang terms to tornadoes are: twister ,whirlwind ,wedge , funnel , gustnado, landspout, willy-willy , or rope.\n\nI hope thats enough.
597609
There are no F6 tornadoes. F1 is the weakest and F5 is the most violent.\nF0-40-72 mph winds\nF1-73-112 mph winds\nF2-113-157 mph winds\nF3-158-206 mph winds\nF4-207-260 mph winds\nF5-261-318 mph winds\nNo tornadoes have been clocked at higher than 318 mph.\n\n69% of all tornadoes are F0 & 1\n29% of all tornadoes are F2 & 3\n2% of all tornadoes are F4 & 5
686091
In the United States (and predominately worldwide), the intensity of a tornado is measured on the Fujita-Pearson Tornado Scale (also known simply as Fujita scale).
977927
Yes, tornadoes have formed in Arizona but Arizona is not part of "Tornado Alley". How "bad" they are is really more dependant on the atmospheric conditions.\n\nYou shouldn't be too concerned though. Tornadoes are small focused events, and the chances of you receiving a direct hit from one (even in tornado alley) is pretty small.\n\nHere's a link showing tornado activity in Arizona. Most tornadoes don't mak it past F1.\n\n~X~
745942
Excellent question!!  And one which is never fully explained on any weather forecast/ weather station....\n\nWeather conditions are controlled by the air currents over the Pacific Ocean, for the most part, first of all.  You can watch typhoons or Pacific hurricanes travel westward, until they reach a landmass, then these low-pressure storms will turn North-Northeast and follow the jet stream, until they are turned South-southeast ward, and affect the U.S. northwest states, Washington, Oregon, California.....\n \nThese extra-tropical storms keep their strength as they travel around the path of the Northern jetstream, droping rain and producing winds not unlike a hurricane, as they follow the jetstream paths around the world.  \n\nAfter these storms, these Pineapple Expresses, have traversed the United States, they again gain strength over the Northern Atlantic ocean, and then let go of the precipatation over Britian and Europe, where the Original storm dies.....\n\nAgain, excellent question.  Hope this enlightens you!!
222466
Dave in NC answered it perfectly.  Ill just add, if you are asking why tornados form over land- The rapid increase in heat needed to cause formation of tornados generally occurs only over land, since water modulates changes in heat.  However, sometimes they do form, but they are called waterspouts, and usually occur near hurricanes.
847338
i read in a tornado book that i bought, tornado alley in the U.S. gets the most tornadoes in the whole world.  Conditions are just right for it here.  There is nowhere else that tornadoes are common, but tornadoes can happen anywhere
410200
Oklahoma has more real tornados per square mile than anywhere else in the world.  Florida has more per square mile, but most are F0 and F1, not enough to do anything.  Texas has more overall, but it's a bigger state.  According to the NOAA, Oklahoma City has had more tornados than any other city.
501639
Technically yes there must be a storm of some kind... But the tornado isn't usually in the center of a storm usually its on the southwestern corner or side of the storm and it might not even be raining in that part of the storm, making it appear that its not in the storm.\n\nTo have a tornado you need these 2 things....\n\n1. A convective rain shower/thunderstorm\n2. Winds in the upper and middle layers of the atmosphere running Perpendicular to eachother, or the winds in the lower and middle layers. ( basically wind blowing in 2 different directions at different altitudes of the storm, like at the ground the wind be blowing from the west and up about 10,000 feet the wind blowing from the south.)\n\nThats really about it... Those dont really mean that you will get a tornado, it just that those things must be present to create a tornado.
1102714
yes.\n\nAt least the great majority of tornadoes rotate counterclockwise \n(as do all low-pressure systems) in the northern hemisphere, and clockwise in \nthe southern hemisphere, for the reason (coriolis force) given by Eric \nPeterson in response #1.  But occasionally, it would seem, northern hemisphere \ntornadoes do rotate clockwise:  S. Flora's book "Tornadoes of the United \nStates" cites an 1890 article in the American Meteorological Journal.  Its \nauthor, a J.P. Finley, states that, of 550 American tornadoes he studied, 29 \nwere deemed to have rotated clockwise.  I have not been able to find any \n"modern" study of this question.  But I believe it could be true. The region \nof swirling air that contracts to become the tornado is not itself large \nenough in extent to have its rotation dictated by the coriolis force; rather, \nit "inherits" this tendency from the great masses of air whose movement sets \nthe stage for the storms and any associated tornadoes. If the study cited is \ncorrect and representative, on occasion the direction of rotation is set by \nsome other factor, perhaps the topography in the area where the tornado forms, \nfor example.
381488
There are three reasons why North America has so many powerful tornados.\n\n1. Cold dry air from the North.\n2. Warm moist air from the gulf of Mexico\n3. The Great Plains.\n\nWhen cold dry air from the north collides with warm moist air from the Gulf of Mexico, the moisture in the warm air condenses forming clouds. When this occures in a way that warm air gets trapped below the cloud cover, and cold air gets trapped above, it creates very unstable conditions.\n\nThe warm air wants to rise and the cold air wants to fall. The result is often a large thunderstorm known as a supercell. \n\nWhen this occures over the central portion of North America, known as the Great Plains, the flat landscape allows for the easy formation of horizontal columns of circular wind. One theory on tornado formation asserts that tornados form when these circulating columns get caught in an updraft (rising warm air).\n\nWhile tornados can form just about anywhere, even in mountainous regions, the Great Plains of North America provides ideal conditions.
1184038
The most number of thunderstorms occur in the tropics, or the zone either side of the equator from about 23.5 degrees north latitude to 23.5 degrees south latitude. \nAs far as the most powerful storms are concerned, the ones with the greatest rainfall tend to be in the tropics, because of so much moisture available. However, thunderstorms that cause severe weather, including damaging winds, hail, and even tornadoes, are generally in the middle latitudes. The middle portions of North America, i.e., the Plains states of the U.S., have the greatest number of tornadoes than any other place in the world.
210554
Argentina could in theory be affected by a hurricane, but is definitely not in a region very favorable for hurricanes.  The southern Atlantic and Eastern Pacific Oceans are very rare to have any hurricanes because there is a lot of wind shear there and ocean temperatures are not as favorable.  There was one "named" storm in that region ever, which hit Brazil last year (though the government of Brazil denies it was a hurricane).  There is no formal tropical weather center for that region.  Argentina is also further south and thus cooler, and even less likely than Brazil to face a hurricane.  So while it is theoretically possible, the odds of Argentina seeing a hurricane in our lifetime are miniscule... so it's definitely not in/on a belt!
301256
No exaggeration. But the type of storm is often different.\nBritain to my knowledge has only had the one hurricane in recent times and that was around 1987. I remember it well. Our position is too far up north for something like Katrina.\n\nSeems you are trying to stir up some storms yourself with a question like this
105363
For a tornatdo to form, there must be cold air, warm air, horizontally spiraling air (casued by the coriolis effect), flat land, no water present. There must be an oncoming wind, and cold and warm aiar that is colliding from the northern and souther latitudes. When the masses of air meet, the warm or moist air will rise, since its density is lower than cold or dry air, ando this will create an upward motion. Now, the oncoming wind will come along (it will be spiraling already), and when it makes contact with the area in which the air masses met, the spiraling wind will basically be violently set upright and so a tornado will form. In the northern hemisphere, the winds will go in a counterclockwise direction and in an inward spiral. (This will be partailly due to the Coriolis effect& if you're in the southern hemisphere, the winds will go in a clockise direction). This is the basic science of tornadoes, as i have just learned this year in my Earth Science course.
481590
Tornadoes are created from severe Thunderstorms. They occur when a high pressure front meets head on with a low pressure front. No where is this more evident than in our mid-west, otherwise known as tornado alley, from the Canadian provinces to the Gulf of Mexico. Here, the Siberian express from Canada meets the warm tropical front from the Gulf of Mexico.