An American documentary RealityTV series on Creator/DiscoveryChannel that follows several teams of storm chasers throughout the Midwestern United States. The show debuted in October, 2007 and was cancelled in January 2012.

Sadly, TWISTEX team leader Tim Samaras, his son Paul, and fellow chaser Carl Young were killed by a 2.6-mile-wide [=EF3=] tornado near El Reno, Oklahoma on May 31, 2013. A tribute episode was aired on June 5, 2013 in their honor documenting the 2.6-mile width tornado, acting as a touching finale to the series.


* CoolCar: A large number of them, including but not limited to the Tornado Intercept Vehicles (TIV and [=TIV2=]), the Dominator, the Doppler On Wheels (DOW) trucks, etc.
* {{Crossover}}: The [=TIV2=] and Dominator were featured on an episode of ''Series/{{Mythbusters}}'', testing the vehicles' ability to withstand tornado-level wind speeds.
* DeathFromAbove: Tornadoes, lightning, and hail produced by supercell storms.
* DoNotTouchTheFunnelCloud: Averted as they have vehicles specifically designed to go into them (the TIV, the [=TIV2=], and the Dominator)
** Subverted on a couple of occasions with the Dominator, as it's not intended to go into the strongest tornadoes. One time a window was blown out (see Eye Scream below) and another time the vehicle was shifted sideways several feet. In 2013 one storm in Oklahoma tore the Dominator's hood completely off.
** Played tragically straight a year after the show's cancellation when TWISTEX team leader Tim Samaras, his son Paul, and fellow chaser Carl Young were killed by an [=EF3=] tornado near El Reno, Oklahoma on May 31, 2013. [[note]]The tornado was originally rated an [=EF3=] before being upgraded to an [=EF5=] primarily due to a DOW wind speed estimate of 296 mph. However, this rating was later controversially downgraded back to an [=EF3=] when damage surveys (which determine all tornado ratings) failed to find evidence of [=EF5=] or [=EF4=] damage. Although many in the storm chasing and scientific communities dispute its accuracy, the tornado's [=EF3=] rating remains official. Regardless, the tornado is still widely and erroneously reported in many places to be an officially-rated [=EF5=].[[/note]] (This is the same tornado as the above-mentioned one that tore the Dominator's hood off.)
* DontTryThisAtHome: Each episode starts with this disclaimer.
* DutchAngle: Some of the vehicle footage. One shot during the "behind the scenes" special shows a cameraman hanging out the back of a moving truck holding his camera inches off the pavement so he can get an angled face-on shot of the Dominator.
* EmergencyBroadcast: Given the subject matter, it's inevitable that you'd hear one of these at some point.
* ExactlyWhatItSaysOnTheTin: The show is about people who ''chase after storms''.
* EyeScream: In one of the earlier seasons, the Dominator's driver side window shattered during a tornado, spraying the occupants with broken glass. After the worst of the wind passes by, Reed says "My eyes are bleeding".
* HeroicBSOD: Sean Casey came close to this; the devastation he witnessed during season 5 made him question his desire to continue chasing. A pep talk from his wife set him straight, however.
* InMediasRes: The first episode of season 4 (the 2010 chase season) started off in the immediate aftermath of the tornado that destroyed Yazoo City, Mississippi, on April 24, 2010, before moving back to a few days earlier. The ''entire'' first episode of season 5 (the 2011 chase season) covered the devastating tornado outbreak that tore through Mississippi and Alabama on April 27, 2011, with the next couple of episodes showcasing events that took place before then.
* JerkWithAHeartOfGold: Reed Timmer. The series frequently shows him to be overbearing, abrasive, needlessly argumentative, and spastic, with the crowning moment being when he kicked driver Joel Taylor out of the Dominator 2 on a Nebraska interstate and left him stranded after a serious disagreement over whether or not they should have chased a storm. That being said, he will drop everything to pitch in and help tornado victims when they come across devastated towns, and is genuinely sympathetic to the victims.
* OlderIsBetter: Of a sort. [[CoolCar TIV 2]]'s frequent breakdowns and failures forced Sean's team to use the original, less advanced TIV for a season and a half.
* OminousFog: One episode of season 4 had Team TWISTEX chasing a tornadic storm in South Dakota that was shrouded in a dense fog bank. Several members commented on how the low visibility may be hiding a tornado such that they might not see it until it was too late. When the fog cleared, however, they were in for a nasty surprise: the storm had produced ''two'' tornadoes, [[OhCrap one directly ahead of them and one right behind them]].
* OhCrap: Frequently in both clean oh crap and less air-able for prime-time TV obscenity versions like when the above happen and when chasing tornadoes mostly when rain-wrapped (heavy rainfall bands obscuring visibility) tornadoes suddenly pop into view at distances less than acceptable for safety.
* ProductPlacement: Reed Timmer appeared in several Bosch windshield wiper blade commercials.
* SceneryGorn: The aftermath of the tornadoes the teams chase, particularly the stronger ones like Yazoo City. Season 5 was replete with this, with the teams witnessing [[http://en.wikipedia.org/wiki/2011_tornadoes multiple powerful tornadoes striking populated urban areas]].
* SeriesGoal: IMAX filmmaker Sean Casey commissioned the [=TIVs=] in order to get inside a tornado for the purposes of capturing footage for his MagnumOpus that will also provide financial security for his family. For season 5, he's filming in 3D for a new movie. Accomplished in the IMAX documentary ''Tornado Alley'' which is essentially TheMovie.
* SmugSnake: Josh Wurman when imposing the 'restraining order' on the TIV 2 team in season 4.
* TooDumbToLive: Some of the civilians the teams encounter, standing around ''outside'' during severe weather or driving right towards a clearly-visible oncoming tornado even with the teams screaming at them to get to shelter.
* WhamEpisode:
** Matt Hughes, a member of the TIV 2 team, finally achieved his goal of getting inside a tornado, only for the viewers to find out that, according to the show, he was fatally injured in an "accident unrelated to chasing" a few days after the episode was filmed. He actually committed suicide.
** ''Mile Wide Tornado: Storm Chasers Tribute'' plays this horribly straight--three Storm Chasers died shortly after the tornado hit when their Chevrolet Cobalt was shredded by another tornado. Though the series was cancelled, this could be considered its GrandFinale.