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1[[quoteright:332:https://static.tvtropes.org/pmwiki/pub/images/TORNADO_1_5195.jpg]]
2[[caption-width-right:332:It can kill you. Still looks incredibly cool, though.]]
3
4->''"Shatter every window till it's all blown away,\
5 Every brick, every board, every slamming door blown away,\
6 Till there's nothing left standing,\
7 Nothing left of yesterday..."''
8-->-- '''Music/CarrieUnderwood, "Blown Away"'''
9
10Tornadoes are quite possibly the most spectacular and destructive of all meteorological phenomena. They are taller than skyscrapers and wider than football fields. Despite their size, they can move very fast. Although they’re made of just air and water, their erratic movement and the capricious nature of their destructiveness can at times make them seem to be driven by an inscrutable will of their own beyond the ken of mortal man. The way they twist and writhe as they move adds to this illusion of life. They are surrounded by myths of both the urban and traditional variety. As far as observable natural phenomena go, tornadoes are probably the closest things in real life to {{Eldritch Abomination}}s[[note]]If you want to extend the comparison even further, it was once thought that merely uttering the word "tornado" (in official weather forecasts) would cause mass hysteria. There are people who are obsessed with seeking them out, and will gibber incoherently when they encounter one. And yes, tornadoes can even have tentacles (horizontal vorticity "noodles" that wrap around the main circulation).[[/note]]. Thus it is quite common for them to show up in fiction.
11
12However, there are a great many misconceptions and myths surrounding them, not to mention numerous unrealistic portrayals in media (which is why DoNotTouchTheFunnelCloud is a trope), so we made this page to set down the facts about these astonishing and potentially deadly whims of weather.
13
14----'''The Basics'''
15* '''What is a tornado?'''
16** A tornado is a rapidly rotating column of air that forms underneath a supercell thunderstorm. More specifically, to be considered a tornado, it must:
17*** contact the ground
18*** have a rotating wind speed of at least 65 mph
19*** contact the base of a cumulonimbus cloud
20* '''How do tornadoes form?'''
21** Speaking in the absolute most generality, a tornado is born from the interaction of warm, moist surface air as it interacts with cool, dry air aloft. Think of it as an extreme case of thermal convection: When a liquid or gas receives heat, its matter will move faster due to the increased activity of its atoms and molecules; eventually, the hot mass will be in contact with cold or warm mass and the transfer of UsefulNotes/{{Energy}} between the two will make the whole material system much more active thermally and mechanically. In the case of a forming tornado, the increase of temperature will make moist surface air less dense, so its hotter mass will experience an updraft which, due to the abrupt increase in speed and direction, will begin to rotate. As the interaction of this updraft and nearby downdrafts occurs, small bits of rotation (called 'vorticity') will be generated. This vorticity is eventually collected by the updraft and aggregated into one single vortex, which eventually tightens up to the point where debris is kicked up, a funnel cloud forms (generated from a pressure drop causing water vapor to condense into droplets), and a tornado is reported.
22* '''What do they look like?'''
23** It varies a lot really, but as for their shape, these are the three most common categories: [[http://farm6.static.flickr.com/5100/5429846368_b97410edea_o.jpg Rope]], [[https://stormtrack.org/library/1995/jun8pix8.jpg Stovepipe]], and [[http://www.sky-chaser.com/image/mwcl2013/m14tor14.jpg Wedge]]. A tornado will often change shape during its existence, and most will eventually end up as a rope tornado near the end (this is called "Roping Out"). Their color depends on two factors, the color of whatever the tornado picks up, and the direction it is viewed from. A tornado's funnel cloud is not always clearly visible either -- it can be blocked from sight by the rain falling from the associated thunderstorm ("rain-wrapped") or simply not dense enough to see easily. That's right. There is such a thing as an ''[[InvisibleMonsters invisible tornado]]''.
24* '''What do they sound like?'''
25** Although it depends on a variety of factors, the most commonly associated sound is a low and steady rumbling sound, often compared to the noise of a passing freight train. For comparison, imagine a particularly windy day, then imagine it about '''50 times louder.'''
26* '''How do we track a tornado?'''
27** Detecting, and tracking, a tornado starts where any severe weather detection typically starts: The weather station. Perhaps the one good thing about a tornado is that, as ''massive'' as they are, the clouds, rain, and hail that form around them means they can show up pretty clearly on a weather radar, and there are several key features that can be used to identify tornadic (yes, that's a word) activity, though the biggest indicator is an obvious rotation of the storm front around a relatively small point on the map.
28** Outside the weather station, "Storm Chasers" gear up, heading to points of interest where a tornado may be forming, often in hopes of getting weather measurements and possibly even catching footage of the funnel touching down, confirming the presence of an active tornado so that the public may be warned.
29** Once a tornado is confirmed and underway, the weather stations and storm chasers will continue to follow, track, and observe the tornado with a combination of weather readouts, live footage, and radar signatures, so that the public can be kept updated as much as possible to the tornado's path and what communities may be at risk.
30** Of course, all of this is not 100 percent perfect; tornadoes are ''dangerously'' unpredictable, and have been known to take sudden turns, unexpectedly increase or decrease their speed across the ground, and even ''reverse their direction of travel'' at any given moment. Storm Chasers have to have nerves of steel and almost always be watching the storm for these sudden changes, lest ''they'' end up being chased. In truth, ''nobody'' in the relative path of a tornado is safe until the tornado itself has dissipated, but still, ''any'' warning is better than no warning at all.
31'''Safety'''
32* '''Tornado Watch, Warning, Emergency'''
33** '''Tornado Watch:''' A Tornado Watch is issued when conditions are ripe for a tornado to form.
34*** '''Particularly Dangerous Situation (PDS) Tornado Watch''': Conditions that are capable of producing ''many'' tornadic storms (an outbreak) and/or supercells capable of producing very strong tornadoes ([=EF3=] or above) are present.
35** '''Tornado Warning:''' A Tornado Warning is issued either when there is considerable evidence that a tornado has formed (or is in the process of doing so) or when a tornado's presence has been visually confirmed. Although you should seek shelter at this point no matter what, not all tornado warnings are created equal, and the exact text of the warning will specify which type has been issued:
36*** A '''radar indicated''' tornado is issued when radar data indicates that a tornado is in the process of forming and ''may'' already be on the ground. This is the least severe type of tornado warning, but again, the advice is still the same.
37*** An '''observed''' tornado refers to either "radar confirmed" tornadoes (issued based on radar data, but with much higher confidence that the tornado is already on the ground) or tornadoes that have been reported as being on the ground by trusted sources (e.g. trained weather spotters or law enforcement).
38*** A '''Particularly Dangerous Situation (PDS) Tornado Warning''' is, in practice, an intermediate step between regular Tornado Warnings and Tornado Emergencies, where the tornado is deemed to be dangerous enough based on radar data and/or initial damage reports to warrant enhanced wording, including the warning of a "life-threatening situation", but not quite enough for an Emergency declaration.
39** '''Tornado Emergency:''' A Tornado Emergency is the most severe tornado warning that can be issued by the National Weather Service. This warning was originally invented on the spot during the Bridge Creek-Moore tornado in 1999, and was soon adopted by other NWS offices throughout the country. However, it wasn't until 2016 that a set of formal criteria for a Tornado Emergency was established: it is to be issued when a large and ''very dangerous'' tornado is actively en route to a populated area, with the threat of catastrophic damage and loss of life.[[note]]On rare occasions, a Tornado Emergency might turn out to be a "dud" where the tornado in question is either much weaker than expected or, in even rarer cases, not on the ground at all. This infamously happened ''twice in a row'' in Arkansas in April 2022. The first time, on April 11, it was due to malicious reports of an extremely large tornado from a woman in UsefulNotes/{{Ohio}} who spoofed her location data to appear as if she was chasing the storm in Arkansas. Although there ''was'' a tornado in that case, it was ultimately only rated [=EF1=]. In the second case, on April 15, everyone was acting in good faith, but the fact that the storm was far away from radar sites meant that the NWS had to rely mostly on reports from the ground, which included law enforcement mistaking an ordinary cloud for a wedge tornado, and storm chasers mistaking straight-line wind damage for evidence of a tornado having ripped through the area. Again, this is ''not'' a normal occurrence. If you get a Tornado Emergency notification, you should ''always'' assume the worst and hope for the best.[[/note]] If you hear this one for your area, '''get to shelter,''' even if you're not normally the kind of person who adheres to regular tornado warnings.
40* '''What to look or listen for'''
41** Strong and persistent rotation in the cloud base. If you see a [[http://en.wikipedia.org/wiki/Wall_cloud wall cloud]] and it is rotating, a tornado is imminent. Obviously, the existence of funnel cloud(s) themselves is ''always'' a warning of tornado conditions.
42** A whirling cloud of dust and debris on the ground under said cloud base. May or may not be at the base of a funnel cloud.
43** Hail or heavy rain followed by either a dead calm or sudden wind shift.
44** A loud, continuous roar or rumble (comparable to the sound of thunder or a passing train) that does not dissipate.
45** Small, bright blue-green or white flashes at ground level.[[labelnote:*]]These are often caused by the tornado ripping through power lines and electrical transformers.[[/labelnote]]
46** ''Persistent'' lowering of the cloud base, or a portion of it.
47** A ''sudden'' power outage (e.g. the power was fine one minute, flickering and/or instantly out the next) if storms are around is also a possibly serious warning sign. If this happens in combination with ''any'' of the above, ''run'' for the best cover in your house, because it means the tornado is heading in your direction, if it's not already right on top of you.
48* '''What to do'''
49** '''NOTICE: FOLLOWING THESE INSTRUCTIONS WILL NOT COMPLETELY GUARANTEE YOUR SAFETY, HOWEVER DISREGARDING THEM WILL PRACTICALLY GUARANTEE YOUR DEATH! REMEMBER, THERE IS NO SAFE PLACE IN A TORNADO, ONLY LESS DANGEROUS ONES.'''
50** In general, the first and best way of ensuring your survival is to prepare. The best ways to do this, well before any tornado watches or warnings are issued, are:
51*** Designate a shelter area and equip it with what you need to survive. This should either be underground (ideally, such as a basement or storm cellar) or an interior room with no windows and no exterior walls. If you live in a mobile home know where your park's community shelter is, or where the nearest solid structure is.
52*** Make a plan so that you are able to get to that shelter in a moment's notice.
53*** For those who live in mobile homes and ''cannot'' evacuate quickly via vehicle or who fear a tornado that can't be escaped - a very good idea is to have an underground shelter built UNDER the mobile home with an entrance to the shelter through the floor of the mobile home or immediately outside one of the door.
54*** You should also have digging tools (at least a strong shovel and thick work gloves) in your shelter space in case you need to dig yourself out, and a whistle, air horn, or other loud alarm devices to get attention for others to help you dig out. If you can't fit digging tools (you're in a bathtub under a mattress, for example) make sure to have that whistle or air horn in your space next to you, and in a way where you will not have to move to use it if you are trapped. While stocking tools in your emergency kit, you should also include a plumber's wrench (the most common tool used to shut off gas lines) and learn how to use it to turn off a potentially leaking gas line or a broken water supply flooding a basement.
55*** Fallout shelters are ''excellent'' for this situation, for obvious reasons.
56*** '''Get a weather radio with battery backup''' so you can be alerted to warnings even if you are sleeping or the power is out. If you have a smartphone, it's a good idea to invest in a quality weather warning app. Newer smartphones on all the major carriers also have support for [[http://www.nws.noaa.gov/com/weatherreadynation/wea.html#.U74SBvnlpe0 Wireless Emergency Alerts]], which will alert you if you are in a warned area. But a weather radio in addition is never a bad idea; cell phones may not be able to provide service or alerts if critical infrastructure is damaged, the weather radio may be old technology but it's done the job well for decades.
57** '''WHEN A WATCH IS ISSUED'''
58*** '''DO NOT''' ignore the watch, just because the weather is clear at that moment. A tornado-producing storm can form and/or move into the area ''extremely'' quickly with the right weather conditions, sometimes within the span of a single ''hour'', and many watches are issued while conditions are still relatively mild or even when the ''sun is shining and the skies are blue'' above you. Even if it is a mistake, just assume the watch is legitimate until you hear otherwise. '''Be ready.'''
59*** If you do not have them on already and are able to get to them, put on a pair of thick-soled shoes when a tornado watch is issued and have a sturdy rain jacket within reach. In the aftermath of a tornado, you will need them. Having a motorcycle helmet with visor (or a bicycle helmet and goggles) nearby is also a good idea, as flying debris striking you in the head could prove to be fatal, and there's going to be a lot of sand/mud/grit/glass you do ''not'' want in your eyes.
60*** Put dogs on leashes and small dogs or cats in carriers. Pet birds and small animals should be put in their cages. If there is room, carriers, cages, and leashed pets should be moved to the shelter area. If there is not room, they should be placed in the most interior room or the basement in general. As for horses and similar large animals there are two schools of thought: one says freeing them to allow to run to safety on instinct is best, the other says keeping them contained is better. As most barns and stables are flimsy structures, it's likely better to allow free running if particularly severe storms are possible or likely, and you can track/identify the horses or livestock.
61*** Make sure your phone is charged (or on charger) and easy to grab fast. Make sure your wallet/purse is in reach - it probably should be kept on you.
62*** If you live in a mobile home and have chosen to flee in a vehicle to stronger shelter/away from the storm, make sure the vehicle has a full or at least half full tank of gas, the tires are properly inflated, and it will start. In fact, if you can do it, the watch is probably the best time to go ahead and evacuate your mobile home for a sturdier building if you can stay at a friend's or family member's or similar.
63*** If there is a watch and/or severe storms are around during sleeping hours, if it is at all possible, sleep in your shelter area (e.g. if you have a basement or underground shelter or safe room capable of sleeping in).
64*** If you ''own'' a fixed structure or especially a space with an underground area capable of occupancy in an area with a lot of flimsy housing such as mobile homes, be a GoodSamaritan and open it/stay open during a tornado threat. Doing this will literally ''save lives'' if a tornado strikes.
65** '''Beware of rain-wrapped tornadoes.''' It's ExactlyWhatItSaysOnTheTin; many tornadoes (especially east of the Rockies) tend to be obscured by heavy rain, making it difficult for them to be seen. Do NOT wait until you see or hear a tornado before taking cover; you should be in a shelter as soon as a warning is issued.
66** '''WHEN A TORNADO WARNING IS ISSUED'''
67** '''If you are at home:'''
68*** Head to an interior closet or bathroom on the lowest floor. If you have a basement, go there. Try to get under something sturdy like a table or a mattress. Do not go under an area where there is a heavy object like a piano or a refrigerator on the floor above, as these would be the places most likely to give way.
69*** Stay as far away from any windows as possible. If they shatter, it will send shards flying everywhere.
70*** When you get to your shelter, get on your knees, crouch down and cover your head, put on your motorcycle helmet and/or bike helmet and goggles, and cover your head [[http://www.spc.noaa.gov/faq/tornado/crouch.jpg like so.]]
71*** '''IF YOU ARE IN A MOBILE HOME, ''GET OUT IMMEDIATELY.'' ''' The unfortunate fact about mobile homes is that their main advantages (low cost and light enough to be readily transported to a new location) make them '' '''VERY''' '' dangerous places to be in a tornado, and even the smallest tornado can tear one apart with little trouble. If your mobile home is in the path of a tornado, '''leave''', and put on your helmet as you go. Then, head to the nearest underground space or fixed structure and get inside, or head into the closest ditch if there isn't anything else nearby. If you have more lead time (20-30 minutes of warning) driving out of the storm's path is a better idea than a ditch. Despite previous advice to the contrary, you even have a better chance of surviving ''driving away from the tornado in a vehicle'' or ''outside in a ditch'' than you do in a mobile home. [[PunctuatedForEmphasis GET. OUT.]] Unless, of course, you have an underground shelter built under or next to the mobile home, in which case get down into it.
72** '''IF YOU ARE OUTDOORS:'''
73*** If there is a fixed structure nearby, like a house or a gas station, head inside and get into an inside room. If you find yourself in a building that has a lot of open space (such as a supermarket or a bank), head for the sturdiest place you can, such as a walk-in freezer or a vault if at all possible.
74*** If there is not a fixed structure nearby, or there is and you don't think you could get to it in time, try and find a low spot, like a ditch, dive into it, lie flat on your belly, and put your hands over your head.
75** '''ON THE ROAD:'''
76*** If the tornado is off in the distance, and there is not much traffic, try and vary your speed and angle and direction as to avoid it.
77*** If the tornado is headed towards you (if it looks like it is steady and not moving, ''IT IS MOVING TOWARD YOU''), find an underground space or a fixed, solid structure and get inside as soon as possible. If there are no such options, pull over to the side of the road, and get into a ditch as far away from the road as possible. '''DO NOT''' seek shelter in an overpass and '''DO NOT''' try to outrun it unless you are experienced enough with weather and sure enough of your surroundings (and the tornado is moving slowly enough) that you are ''certain'' of escape.
78*** If the tornado is headed towards you and you do not think you have time to do any of the above, buckle your seat belt (as it should be already), roll up your windows, put your head between your knees, put on any helmet and goggles you might have (from a motorcycle helmet to a hard hat), and leave the vehicle running so the air bags will activate if there is a collision. This should be your ''very last resort,'' because your odds of surviving with it are very, very low.
79** '''After the Tornado:'''
80*** '' '''Remain calm.''' '' Freaking out will make things worse, and will get in the way of your ability to make decisions.
81*** If you are trapped in debris, calculate your situation before you move. Are there downed power lines or open electrical wiring in your way or on you? If so, DO NOT MOVE. Will moving collapse the structure or debris further on you or on others? If the answer to that is no and you can get out of the debris under your own power, do so. Otherwise, scream, use your phone if it still works to call 911, make use of your air horn or whistle - make as much noise with as little movement as possible.
82*** In the same way, be absolutely careful when lifting debris off of others. Yes, you may want to just get your little brother out NOW. But being aware of electric shock hazards and worse collapses will save both your lives.
83*** If you are with family members or any other group, '''STAY TOGETHER''' and wait for emergency personnel.
84*** ''' ''Watch your step!'' ''' After a tornado, there will be debris '''everywhere.''' You need to be aware of where you are putting your feet so you don't accidentally step on an exposed nail. This is why when watches are issued, you should wear thick work boots or combat boots.
85*** ''' ''STAY AWAY FROM DOWNED POWER LINES.'' ''' They don't flash and spark like in the movies.
86*** ''' ''DO NOT LIGHT A MATCH OR A LIGHTER.'' ''' There will be a significant chance that the tornado caused a gas line to rupture. This is also why you need that plumber's wrench mentioned earlier in your emergency kit - if you see destroyed structures or smell gas, turning off the gas to them will prevent fires and explosions if firefighters haven't already arrived to do so.
87*** Follow any instructions given to you by emergency personnel. It is their job to make sure that you stay alive, so following their orders is in your best interests.
88*** If the medics say that you are OK, then go out and help. After a tornado, especially a big one, emergency services will be stretched to their limits, they will need all the help they can get.
89*** Related to the above, if you have a vehicle that runs (even with broken windows or cosmetic damage), especially a truck or van or similar large vehicle, you can provide some of the most valuable help possible - transporting injured people to medical assistance, towing or pushing debris that blocks roads, and similar. Even a smaller car incapable of towing or carrying injured people/navigating roads full of debris can be helpful in a vital way - charging phones and tablets so people, especially in an area with power outages, can get information and warnings of other storms in the area. Similarly, if you have a generator that is fueled and works, inform emergency crews of this as well - any source of power is very much needed.
90*** Stay out of heavily damaged houses, they could collapse at any time.
91* '''WHAT NOT TO DO:'''
92** '''AT HOME:'''
93*** '''DO NOT LEAVE YOUR HOUSE.''' Unless you are in a mobile home OR the tornado is already wiping fixed structures from their foundations elsewhere, your best bet is to stay put. Leaving a fixed structure will only '''increase''' the chances of you getting killed in anything below an [=EF5=]. A storm capable of spawning a tornado will also be capable of producing rain in mass quantities, high winds, and hail. Flash floods are also possible.
94*** '''DO NOT''' run around and try to open every door and window. It will rob you of valuable time you need to take shelter.
95** '''ON THE ROAD:'''
96*** '''DO NOT TRY AND HIDE UNDER AN OVERPASS. THIS WILL ''NOT'' PROTECT YOU FROM A TORNADO.''' The details will be explained below.
97
98'''Ratings'''
99* ''' The Fujita Scale''' or '''F-Scale''' was developed by Dr. Ted Fujita as a way to equate certain amounts of damage with a tornado's wind speed. Implemented in 1971, it ranked tornadoes on a six-point scale from 0 to 5. It was a good idea, but it had some major problems, such as its inability to take into account how different structures handle being struck by a tornado or that the evaluation of the damage itself was very subjective. On February 1, 2007, the F-Scale was replaced with the Enhanced Fujita Scale, but only in the United States for a period of time; UsefulNotes/{{Canada}} didn't switch over until April 1, 2013. Any tornado that was previously ranked using the Fujita Scale was not reevaluated post-switchover, so a tornado that was ranked as an F3 in 1997 (for instance) would remain an F3, regardless of whether or not its damage would have justified a higher, lower, or similar rating on the EF-Scale.
100** An F0 has wind speeds ranging from 40 to 72 mph.
101** An F1 ranges from 73 to 112 mph.
102** An F2 ranges from 113 to 157 mph.
103** An F3 ranges from 158 to 206 mph.
104** An F4 ranges from 207 to 260 mph.
105** An F5 ranges from 261 to 318 mph.
106* ''' The Enhanced Fujita Scale''' or '''EF-Scale''' is the successor and improved version of the Fujita Scale. Unlike the F-Scale, the EF-Scale is much more specific about what sorts of damage results in where a tornado is ranked. It also takes into further account how different factors effect how much damage a structure suffers, such as the kind of structure, how it was built, how well it was built, effects of debris, etc. Like the F-Scale it was based on, the EF-Scale ranks tornadoes on a 6-point scale from 0 to 5.
107** An [[https://upload.wikimedia.org/wikipedia/commons/0/0d/Sunset_Beach_EF0_damage.jpg EF0]] has wind speeds ranging from 65 to 85 mph.
108** An [[https://upload.wikimedia.org/wikipedia/commons/6/6e/EF1_damage_Richardson%2C_Texas.jpg EF1]] ranges from 86 to 110 mph.
109** An [[https://upload.wikimedia.org/wikipedia/commons/7/7d/WelchEF2Damage2012.jpg EF2]] ranges from 111 to 135 mph.
110** An [[https://upload.wikimedia.org/wikipedia/commons/a/a8/January_23%2C_2012%2C_Center_Point%2C_Alabama_tornado_damage.JPG EF3]] ranges from 136 to 165 mph.
111** An [[https://upload.wikimedia.org/wikipedia/commons/7/71/Moore%2C_OK_EF4_damage_DOD9.jpg EF4]] ranges from 166 to 200 mph.
112** An [[https://upload.wikimedia.org/wikipedia/commons/c/ce/EF5damageMoore2013.jpg EF5]] is any tornado with winds above 200 mph.
113* To better convey tornado severity to the public, the National Weather Service will often use a few different qualitative terms that refer to certain ranges of the F and EF scales:
114** "Significant" tornadoes are anything rated [=EF2=][[note]]or F2 if they're using the original scale; the ranges referred to are the same across both[[/note]] or above. Convective weather outlooks[[note]]which specifically detail the probabilities of strong winds, hail, and tornadoes throughout the contiguous US for a given day; flooding, wildfires, and other forms of severe weather are covered by other SPC and WPC outlooks[[/note]] issued by the Storm Prediction Center will occasionally mark out a "hatched" area in addition to the standard tornado probabilities, indicating that the tornadoes within that area have a high chance of being significant. Often, this "hatched" area will determine whether the overall convective risk for the day is "enhanced", "moderate", or "high".
115** "Weak" tornadoes are [=EF0-EF1=], "strong" tornadoes are [=EF2-EF3=], "intense" tornadoes are anything [=EF3=] or above, and "violent" tornadoes are [=EF4=] or above. Tornado watches will sometimes make reference to the possibility of "strong" tornadoes, while "intense" and "violent" are used in "public weather outlooks".[[note]][=PWOs=] are another forecast product issued by the SPC; these explain in layman's terms the risk of an impending severe weather outbreak.[[/note]]
116** The EF scale still suffers the problem of US-centrism, since it was designed with American building codes in mind. Although an "International Fujita scale" (IF) has been proposed by the European Severe Storms Laboratory, it remains relatively obscure.
117* The '''TORRO scale''', abbreviated as "T", is mainly used in Europe. This one is somewhat more detailed, ranging from T0 to T11. Technically, this is a true wind speed scale rather than a damage scale (which is what the Fujita scale is), although in practice damage surveys are still the main method of determining the rating.
118** A FC (Funnel Cloud) rating is designated to anything with wind speeds 38 mph and below, but is usually determined by tornadic events that have not reached the ground.
119** A T0 has wind speeds ranging from 39 to 54 mph.
120** A T1 ranges from 55 to 72 mph.
121** A T2 ranges from 73 to 92 mph.
122** A T3 ranges from 93 to 114 mph.
123** A T4 ranges from 115 to 136 mph.
124** A T5 ranges from 137 to 160 mph.
125** A T6 ranges from 161 to 186 mph.
126** A T7 ranges from 187 to 212 mph.
127** A T8 ranges from 213 to 240 mph.
128** A T9 ranges from 241 to 269 mph.
129** A T10 ranges from 270 to 299 mph.
130** A T11 is any tornado with winds above 300 mph.
131* Note that these terms are all relative: a "weak" tornado can still pose a serious threat under the right circumstances. Also note that just because a tornado is "violent" does not mean it will actually cause any human casualties, although a tornado at that strength certainly has a high potential to do so.
132
133'''Other Terms and Terminology'''
134* '''Supercell:''' The type of thunderstorm that most tornadoes spawn from. They contain a large rotating core called a mesocyclone.
135* '''Gust Front:''' Also known as the outflow boundary, this is a mass of rain-cooled air flowing out in front of a supercell. These masses of air are known to produce severe straight-line winds.
136* '''Gustnado:''' A whirl often mistaken for a tornado. Gustnadoes are formed from an eddy in a supercell's outflow boundary, or gust front,as it fans out in front of the storm.
137* '''Landspout:''' Tornadoes not associated with a supercell's mesocyclone. Often weaker than supercell tornadoes, they tend to form a distinctive tube-shape and are usually short-lived.
138* '''Tornado Family:''' Tornadoes that spawn from the same supercell are referred to as this.
139* '''Tornado Outbreak:''' An event where multiple supercells within a larger system each spawn multiple tornadoes.
140* '''Tornado Outbreak Sequence:''' An extended period (usually 4+ days in a row) of tornadic activity caused by multiple tornado outbreak-producing storm systems in quick succession.
141
142'''Myths'''
143* Website/{{Wikipedia}} has an extensive page on [[https://en.wikipedia.org/wiki/Tornado_myths tornado myths]].
144* '''General Misconceptions'''
145** '''The winds of a tornado are exclusively located within the "suck zone" of the funnel cloud. DoNotTouchTheFunnelCloud.'''
146*** '''False:''' The funnel cloud is only the center. The tornado proper extends ''well'' outside the funnel cloud, which is why it's not uncommon to see a debris cloud which is much wider than the funnel (case in point, the page image). The funnel cloud is simply the part of the tornado where the pressure drops low enough for water vapor to condense.
147** '''The wind of a tornado are exclusively vertical.'''
148*** '''False:''' Tornadoes are areas of rotating ''horizontal'' winds.
149** '''Tornadoes destroy mostly by dropping the atmospheric pressure, causing houses to explode.'''
150*** '''False:''' Tornadoes destroy mostly by their intense winds, along with picking up objects and turning them into projectiles to pummel other things (like your house). If you watch any footage of a tornado destroying something, you will notice that the structures tend to be blown ''away'' rather than blown ''up''.
151** '''There are no tornadoes in _____.'''
152*** '''FALSE.''' In the US alone, every single state has recorded at least two tornadoes since 1950 (UsefulNotes/{{Alaska}} is the "two"). While this is a half-truth in that ''generally,'' tornadoes, say, in UsefulNotes/{{California}} are rare and generally under [=EF2=] if that, they can and do happen there, and weaker tornadoes aren't nothing to ignore especially in areas unprepared for them, because said areas often have more glass in more places, weaker building codes for wind, and the like. An [=EF0=] or [=EF1=] that becomes a whirlwind of glass in a populated open area with no one sheltering can be as if not more deadly than an [=EF3=] with everyone in proper shelters or that only hits vacant areas.\
153\
154Also, the UsefulNotes/UnitedStates and Canada (and northern UsefulNotes/{{Mexico}}) aren't the only parts of the world that see tornadoes. The country with the highest number of tornadoes per unit area? It's either ''UsefulNotes/TheNetherlands'' or the ''[[UsefulNotes/UnitedKingdom UK]]'', depending on the source. Other parts of the world that see reasonably frequent tornadoes are the rest of Europe, UsefulNotes/SouthAfrica, the Río de la Plata basin in UsefulNotes/SouthAmerica, the Ganges River basin of South Asia, eastern UsefulNotes/{{China}}, UsefulNotes/{{Japan}}, Korea, the UsefulNotes/{{Philippines}}, UsefulNotes/{{Australia}}, and UsefulNotes/NewZealand.
155** '''The sky turning an eerie shade of green is a telltale sign of a tornado.'''
156*** '''Partially true:''' A green sky can be a sign of severe weather in general, not just a tornado.
157* '''Safety'''
158** '''You can outrun a tornado in a vehicle.'''
159*** '''BOTH TRUE AND FALSE.''' In some circumstances (e.g. if you can clearly see the tornado and track the direction in which it is moving), you not only ''can'' but ''should'' drive away from it. People have survived tornadoes doing this (and it's how storm chasers generally survive being near tornadoes). At the same time, there are situations where you ''cannot'' outrun a tornado in a vehicle, and in those situations, you are best getting off the road ''immediately'' into the strongest structure available. Of note is this storm chaser's opinion on the matter: http://stormhorn.com/2010/11/14/leave-your-car-and-take-shelter-in-a-ditch-not-so-fast/
160*** Other factors to consider when deciding when to run from a tornado include traffic conditions, the state of your car, and the state of local roads. If any of these could leave you stopped in the tornado's path, you'd be safer if you parked and got under shelter.
161*** If you must leave your car to seek shelter, pull over to the side as far as possible to avoid impeding other drivers or emergency personnel. And needless to say, never venture onto unpaved roads or open fields to escape a tornado. Heavy rain can turn these into a bog in minutes, snaring your car AND making it more difficult for emergency vehicles to reach you if you need them.
162** '''Overpasses provide safe shelter from a tornado.'''
163*** '''[[PunctuatedForEmphasis FALSE! VERY! VERY! FALSE!]]: ''Never''''' seek shelter under an overpass during a tornado!
164*** The winds of a tornado are horizontal, not vertical. They are not "sucking you up"; they are coming at you very hard from the side. A surface above your head will do ''nothing'' to protect you from them. Additionally, the winds are ''rotating'', meaning that you will get hit from all four sides. An overpass might block, say, the south wind, but the north wind will be coming right at your face -- and because the winds can still get to you, the objects and debris they are carrying can too.
165*** The instinctive 'safe zone' of an underpass -- the triangle where the sloping wall meets the roadbed -- is actually the most dangerous place to be. The winds will be stronger there, both because it is higher off the ground and because they are being funneled through a smaller space. Some overpasses have horizontal girders, but many do not; and even if your overpass does, the rotation of the winds will make it near-impossible for you to brace yourself.
166*** Even if the tornado doesn't hit, parking under an overpass usually means stopping in a traffic lane, which is illegal ''and'' dangerous to you and those around you. Another car might plow right into you because they couldn't see you in time to stop. If a number of vehicles park there, it will effectively block the road, trapping other drivers in the storm's path and keeping emergency response vehicles from getting to where they are needed, endangering even more lives.
167*** '''Why does this myth persist?''' It most likely runs on two things: the fact that overpasses themselves survive tornadoes and the CommonKnowledge that the main hazard of a tornado is vertical suction within the funnel itself. It doesn't help that there is at least one highly-publicized case where a news crew successfully weathered a tornado under an overpass -- the [[https://en.wikipedia.org/wiki/April_26,_1991_tornado_outbreak#El_Dorado_Lake.2FKansas_Turnpike_Underpass.2C_Kansas 1991 El Dorado, Kansas tornado]] -- '''BUT''' this was something of an anomaly. Firstly, the tornado did not directly strike. Secondly, this particular overpass had heavy girders forming an odd, sheltered "box" under the roadway which blocked much of the horizontal force of the wind -- a feature distinctly ''lacking'' in most overpasses. Nevertheless, many others have decided that this "proves" that an overpass provides shelter from a tornado and paid the price; case in point, on May 3, 1999 three different overpasses took direct hits from tornadoes, two of these from the legendary [[https://en.wikipedia.org/wiki/1999_Bridge_Creek-Moore_tornado Bridge Creek-Moore, Oklahoma tornado]]. At least one ''fatality'' occurred at each overpass, and virtually everyone that managed to survive suffered moderate to life-threatening injury, including compound fractures and shattered bones, lost fingers, lost ears, lost noses, and impalement by pieces of shingles, 2x4s, etc.
168*** In short, an overpass is ''no'' substitute for being in a well-built structure, or better yet, being underground. If you absolutely, positively must shelter underneath one, get as low to the ground as you can and cover your head with your arms.
169** '''If a tornado is about to strike your house, opening all the windows will reduce the damage.'''
170*** '''False:''' This bit of folk wisdom depends on the myth that tornadoes 'explode' houses through the difference in atmospheric pressure. In reality, tornadoes destroy houses through rotating horizontal winds and airborne heavy objects (i.e. cars). Opening windows does nothing to prevent either of these and only wastes time you could be using to make ''yourself'' safe.
171** '''The northeastern most corner of a house is the safest.'''
172*** '''False:''' The rationale behind this one is the myth that tornadoes only move northeast, which we will get to later, but this one is false because it forgets that the ''winds'' of a tornado are circulating even when the tornado itself is moving in a straight line.
173** '''The southwestern most corner of a house is the safest.'''
174*** '''False:''' This one, which may be heard more often than the "northeastern most corner" version above, is based on the idea that debris will be blown ''away'' from the southwestern part of a house. Again, however, this ignores the circulation of a tornado's winds.
175** '''No tornado sirens means no danger.'''
176*** '''FALSE''': Some places (e.g. in the West and Northeast and South US outside of Tornado Alley, for example in UsefulNotes/{{Colorado}} or UsefulNotes/{{Montana}} or UsefulNotes/{{New York|State}} or UsefulNotes/NorthCarolina ''et cetera'') often do not have sirens or other outdoor warning systems, or immediately usable ones to be sounded for a weather threat. Even in places with sirens, winds and rain can drown out their effective range (as in, you can't hear the siren going off or can only faintly hear it), as can city noise in an urban area. Or sirens are run on main electric power, which means if the power goes out they do too. Or someone doesn't trigger them or they don't work for some reason or other. While any civil defense siren going off ''definitely'' means you should take shelter and check to see what is happening while you do (don't assume it's a test!), you should also not assume that sirens will warn you of tornadoes - again, get a weather radio, and if you have a smartphone, a weather warning/storm conditions app and/or enable emergency alerts, and if there is severe weather around, pay attention and keep an eye out, because sometimes, although less common than in the past, a dangerous storm can escape notice entirely until someone spots it.
177** '''Tornado warnings happen all the time/the sirens go off every storm, there's no need to take shelter unless things look dangerous.'''
178*** '''FALSE''': A tornado warning or siren activation is only issued under two circumstances: Doppler radar has determined a storm contains a rotating mesocyclone which may form a tornado at any minute (if it hasn't already done so) or someone has reported funnel clouds or a tornado touchdown. It isn't a watch, nor is it even a severe thunderstorm warning, which imply lesser hazards. If it's a tornado warning, there is reason to believe there is an actual tornado. Also, while warnings used to be issued for entire counties (which did make this misconception ''slightly'' true, in that most tornadoes aren't big enough to flatten an entire county so a tornado could "miss," say, the northern part of a county, which led people to be far more cavalier about warnings in tornado prone areas), and even once for an ''entire state'' (Indiana during the 1974 Super Outbreak), this is no longer the case: warnings are targeted toward a tornado's actual path as of TheNewTens. Also, especially at night or in heavy rain/fog/hail conditions, sighting a tornado even at close range may be near impossible. (As an example, people thought the Tri-State Tornado was a fog bank). The ''only'' thing still even slightly true about the idea that tornado warnings can be ignored is that ''most'' tornadoes are relatively localized with fairly small in comparison damage zones (which is why tornado recovery is often faster than, say, hurricane or earthquake recovery, because resources aren't themselves destroyed within a 50-100 mile radius), that said, are the odds you won't get hit worth what happens if you ''do'' get hit unprepared and unsheltered? Especially when the worst thing that can happen from heeding the warnings and taking shelter being some inconvenience or wasted time (which ''dying in a tornado'' tends to be a lot more of)?
179* '''Behavior'''
180** '''Skipping Houses'''
181*** '''True ''and'' False:''' Tornadoes have gotten a reputation for seemingly "skipping" over houses. Seemingly lifting off of the ground and then coming down again. However, they truly don't do that. At least, not in ''that way''.
182*** A tornado's intensity can vary greatly during its lifespan. Sometimes a tornado will briefly weaken to where it won't do much damage and then quickly re-intensify and start doing damage again.
183*** Some violent tornadoes can briefly split apart at the base into multiple vortices that will simply pass by one structure and hit the one next to it.
184*** Some violent tornadoes can also cause a "satellite" tornado to form, which also have the same effect.
185*** Tornadoes ''are'' capable of "skipping" in the sense that it will briefly lose contact with the ground. However, this tends to be more like skipping neighborhoods than skipping individual houses.
186** '''Bigger = Stronger'''
187*** '''False:''' While there is a trend for larger tornadoes to be stronger, that is not always the case.[[http://upload.wikimedia.org/wikipedia/commons/9/98/F5_tornado_Elie_Manitoba_2007.jpg This]] tornado that struck Elie, Manitoba was an F5 (Canada's first and only F5.)
188** '''No funnel cloud = No tornado'''
189*** '''False:''' Not all tornadoes have a visible funnel cloud.
190** '''All tornadoes travel northeast'''
191*** '''False:''' Many do, but not always. Belief in this is what likely got several storm chasers killed or injured (including the very experienced scientist chaser Tim Samaras, who was killed along with his son and his chase partner, and a crew from Creator/TheWeatherChannel that got injured) in the 2013 El Reno, UsefulNotes/{{Oklahoma|USA}} tornado -- most of the chasers who came too close to the tornado seemed to be traveling under the assumption that the tornado was moving northeast. The circulation was simply too wide (with satellite tornadoes and variable wind directions) to have ''any'' safety margin in almost any direction -- distance and/or shelter, not direction, was the only safeguard.
192*** The [[https://en.wikipedia.org/wiki/1997_Central_Texas_tornado_outbreak#F-5_Jarrell_tornado May 27, 1997 Jarrell, Texas tornado]] is infamous among those who study tornadoes for a multitude of reasons, namely the [[https://extremeplanet.wordpress.com/2012/06/26/aerial-damage-from-the-f5-jarrell-tornado-the-most-intense-tornado-damage-ever-photographed/ absolutely devastating]] damage it caused (which was arguably made worse because the tornado itself was an unusually slow-moving one) coupled with the fact that the tornado went from a stationary rope tornado to a multi-vortex wedge tornado that abruptly started heading southwest and literally wiped an entire neighborhood off the face of the earth.
193** '''A clear sign that a tornado is near is that it starts hailing.'''
194*** '''True and False''': While severe weather systems that produce tornadoes may also produce hailstones, a tornado does not equal hailstones, nor vice versa. In fact, many storm chasers have reported the rain and hail actually letting up the closer they got to the tornado itself. As mentioned above, while heavy rain or hail can be a telltale sign that you're in the middle of a tornado-producing storm, don't assume that the danger has passed just because the rain and hail stopped, ''especially'' if it stops suddenly.
195* '''Geography'''
196** '''[[TrailerParkTornadoMagnet Trailer Parks Attract Tornadoes]]'''
197*** '''False:''' Tornadoes do not discriminate. This myth likely arises from the reality that tornado strikes on mobile homes (which are incapable of surviving even the weakest tornadoes) are dramatic enough to stick in common memory. Television news crews perpetuate the myth by filming at trailer parks, where the easily-damaged mobile homes provide ample shots of extreme devastation.
198** '''Tornadoes cannot strike downtown areas.'''
199*** '''False:''' [[http://en.wikipedia.org/wiki/List_of_tornadoes_striking_downtown_areas_of_large_cities Yes, they absolutely can.]] It's rare since the odds of a tornado hitting any one particular area is a complete game of chance, but it is still possible. See the Costliest Tornado below; the current record holder was costly ''because'' it hit a downtown area.
200** '''Tornadoes cannot cross rivers/hills/valleys/mountains.'''
201*** '''False:''' While ground features such as mountains, valleys and forested areas may disperse and redirect the wind, Tornadoes themselves are in no way hindered by the terrain. There are several cases of tornadoes crossing rivers, going over hills, crossing valleys, and even ''climbing mountains.'' Again, the terrain does nothing. Some places, like forests and mountains, are arguably even ''more'' dangerous during a tornado because of the risk posed by falling trees and other debris dislodged by the high winds.
202** '''Tornadoes only happen in Tornado Alley/flat plains regions.'''
203*** '''''EXTREMELY FALSE''''': As mentioned above, a tornado can happen '''''anywhere,''''' whether in Tornado Alley, in the mountains, Europe, Kalamazoo, your grandma's house, etc. Even the ''ocean'' isn't safe from tornadoes, though they typically go by "waterspouts" when on water. The only place where a tornado would never strike is a place which there is no weather (and by extension '''no atmosphere''' to cause weather) and if you find yourself in a place like that, then you probably have bigger problems.
204
205'''Tornadoes and Climate Change'''
206
207The effects of climate change on tornado climatology are still somewhat unclear. Although the National Weather Service keeps a database of all known tornadoes in the US since 1950, one must be careful with using this data to make predictions about tornado frequency and intensity:
208** First, the further back you go, the fewer tools meteorologists had at their disposal to detect tornadoes. This means that the average number of reported tornadoes per year went from a few hundred in the 1950s to over a thousand in the 21st century. This also means that there will be a bias in older data towards tornadoes with higher Fujita ratings, which are on average larger, longer-lived, and more likely to hit populated areas[[note]]Because the Fujita scale measures tornado ''damage'', more structures being hit effectively means more points along the tornado's path are being sampled, meaning a higher likelihood of damage being found that indicates a higher rating. It's not a coincidence, then, that two of the nine [=EF5=] tornadoes recorded in the 21st century, along with several from the 20th century, have hit major population centers.[[/note]] and thus more likely to be spotted.
209** The conflation of the F and EF scales may give the false impression that tornadoes have gotten weaker since 2007. In reality, the original Fujita scale did not take into account the quality of construction of individual buildings, which resulted in many tornadoes getting higher ratings than were warranted. As of 2022, it's been an unprecedented ''9.5 years'' since the last [=EF5=] tornado, which has primarily been attributed to increasing standards about what constitutes [=EF5=] damage, rather than any actual decrease in tornado strength. Furthermore, when the Fujita scale was first developed, the wind speeds needed to cause certain levels of damage were mostly unknown, and so the listed speeds for each category were essentially complete guesswork. Once the enhanced scale was made, and extensive testing was done to see how different structures would react to different wind speeds, it was found that the values given for each category were all significant overestimates. Overall, this means that pre-2007 tornadoes are listed as being far more intense than they really were.
210
211Tentatively, there does seem to be a trend, however: Tornado Alley appears to be shifting east. The term "Dixie Alley" has been used to refer to an area of the southeastern US centering on Mississippi and Alabama, which, although not traditionally part of Tornado Alley, is hardly less susceptible to devastating tornadoes. "Hoosier Alley" (referring to parts of the Midwest and centered on Indiana) as well as "Carolina Alley" ([[ExactlyWhatItSaysOnTheTin referring]] to [[UsefulNotes/NorthCarolina the]] [[UsefulNotes/SouthCarolina Carolinas]]) have also been coined, though are somewhat less common. This is still a troubling development for several reasons:
212** Higher population density in the eastern US compared to the Great Plains.
213** Manufactured homes are more common in the South than anywhere else in the US. These are often referred to as tornado death traps, and for good reason. A tornado as weak as [=EF2=] will be enough to completely destroy these, whereas other structures will fare far better in the same conditions.
214** The terrain in these areas is usually more hilly and wooded, obscuring tornadoes that do form.
215** Dixie Alley tornadoes are more likely to be rain-wrapped, again making them harder to see.
216** Whereas classic Tornado Alley tornadoes usually occur in the afternoon and evening hours, it's not uncommon for Dixie Alley tornadoes to strike at night, making them impossible to see without the occasional helpful lightning flash, and while people are asleep. Nighttime tornadoes are consistently more likely to cause fatalities.
217** Although there is still a peak tornado season in Dixie Alley (specifically, around April), off-season tornado outbreaks are somewhat more common and may catch residents off-guard.
218
219'''Tornado Extremes'''
220* '''Most Destructive Tornado'''
221** This label is an infamous matter of opinion (especially on storm chaser forums) since one person's definition of "most destructive" varies from another's, especially when you take fatalities, damage to physical structures, speed, and so on into account, so in the interest of keeping things civil, we won't be giving our opinion on this page. That being said, those aforementioned variables (among others) ''do'' have records that aren't contested or disputed as of this writing, so they will be listed below.
222* '''Largest Tornado Outbreak'''
223** The April 25–28, '''2011 Super Outbreak'''. This outbreak consisted of 134 [=EF0s=], 140 [=EF1s=], 49 [=EF2s=], 22 [=EF3s=], 11 [=EF4s=], and 4 [=EF5s=], for a grand total of 360 tornadoes. Tornadoes were reported from UsefulNotes/{{Texas}} all the way north through to UsefulNotes/{{Michigan}}, UsefulNotes/{{New York|State}}, and even into [[UsefulNotes/CanadianProvincesAndTerritories Ontario]]. It also set records for most tornadoes recorded on a single calendar day and any 24-hour period in a single outbreak. Measured by US Central Time, 216 touched down on April 27, and 219 touched down from 12:40 am on April 27 to 12:40 am on April 28.
224* '''Most Violent Tornado Outbreak'''
225** Defining "most violent" as the one with the highest number of tornadoes of [=F3/EF3=] or greater, this record belongs to the ''previous'' holder of the record for largest outbreak: the April 3–4, '''1974 Super Outbreak'''. Of the 147[[labelnote:*]]The original count was 148, but later studies reclassified one as a microburst.[[/labelnote]] tornadoes recorded in 13 US states and Ontario, 34 were [=F3s=], 23 were [=F4s=] and 7 were [=F5s=]. Forecasters had so much trouble keeping up with the activity that at one point, they placed the entire state of Indiana under a tornado warning—the first and only statewide warning in US history.
226* '''Most Prolific Tornado Outbreak'''
227** Defining "most prolific" as the most tornadoes in the shortest time span, the most prolific outbreak was the November 23, '''1981 United Kingdom outbreak''', which saw 104 tornadoes touch down in UsefulNotes/{{England}} and UsefulNotes/{{Wales}} in ''5 hours, 26 minutes''. Most of the tornadoes were weak, but still caused significant damage (though thankfully no deaths).
228* '''Deadliest Tornado'''
229** '''USA'''
230*** '''The Tri-State Tornado''', March 18, 1925. 695 people were killed by this tornado, whose path ran through UsefulNotes/{{Missouri}}, Illinois, and Indiana. The Illinois phase was responsible for record fatalities in a single city (234 in Murphysboro) and a single school (33 at the De Soto School in De Soto).
231** '''World'''
232*** '''The Daulatpur-Saturia, Bangladesh Tornado''', April 26, 1989. ~1,300 people were killed by this tornado.
233* '''Costliest Tornado'''
234** '''The Joplin, Missouri Tornado''', May 22, 2011. This tornado caused approximately $2.8 ''billion'' in damage.
235** There's a very good chance that the December 10, 2021 '''Western Kentucky tornado''', which traveled more than 160 miles through the state, will break this record. While damage estimates are ongoing, nearly ''75%'' of the small town of Dawson Springs (population about 2,500) was wiped off the map, and more than half of the considerably larger town of Mayfield (population about 10,000) suffered major to catastrophic damage.
236* '''Longest Track and Duration'''
237** '''The Tri-State Tornado''', March 18, 1925. This tornado traveled over 219 miles, started in Missouri before crossing the Mississippi River into Illinois and then passing into Indiana. In all it cut through three states (hence the name) in a time span of 3 and a half hours. However, modern tornado historians have been unable to confirm that the tornado actually remained on the ground the whole time, and many believe the so-called "Tri-State Tornado" was actually multiple tornadoes spawned from the same supercell.
238** The '''Western Kentucky tornado''' of December 10, 2021 is the longest-lived tornado of the modern era, traveling 165.6 miles in just under 3 hours. The parent supercell existed for even longer, tracking for about 250 miles through Arkansas, Missouri, UsefulNotes/{{Tennessee}}, and Kentucky, and it was initially believed that a single tornado had remained on the ground for that entire time. If true, this "Quad-State tornado" would have ''broken'' the 1925 record. However, like with the Tri-State tornado, further analysis revealed gaps in the damage path indicating that a tornado dissipated and a new one formed from the same cell.
239* '''Widest'''
240** '''The El Reno, Oklahoma Tornado''', May 31, 2013. This tornado peaked at 2.6 miles wide.
241* '''Fastest Forward Speed'''
242** '''The Tri-State Tornado''', March 18, 1925. This tornado was not only long-lived and powerful, but also ''[[FromBadToWorse fast]]'', with a forward speed of 73 mph.
243*** An honorable mention has to be given to the aforementioned 2013 El Reno tornado. While the tornado itself had a forward velocity of 55 mph, some of the subvortices traveling along its southern edge were clocked in excess of [[Main/SuperSpeed 100 mph.]]
244* '''Fastest Wind Speed'''
245** '''The Bridge Creek-Moore, Oklahoma Tornado''', May 3, 1999. Wind speeds of up to 302 ± 22 mph (possibly up to 324 mph at an estimated max, with the confirmed speed of 302) recorded by mobile Doppler radar units -- the fastest wind speed recorded on Earth, incidentally.
246* '''Most Times Struck By Tornado'''
247** '''Oklahoma City, Oklahoma, US'''. Counting the metro area ''and'' the suburbs such as Bridge Creek and Moore, the Oklahoma City region has been hit by at least five significant tornadoes, two of them being [=F5/EF5=].

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