Four vehicles dominate any conversation about driving toward a tornado on purpose: Sean Casey's two Tornado Intercept Vehicles, Reed Timmer's Dominator series, and the Doppler on Wheels radar trucks. They are built for different jobs and it shows in every figure. Here they are side by side.
How much do storm chase vehicles weigh?
The TIV 2 is the heaviest of the intercept vehicles. It debuted in 2008 at 16,500 pounds, and after a first season of mechanical failures the team re-armored it, swapping less critical steel for aluminum and rebuilding vital sections in a composite of thin steel, Kevlar, polycarbonate and rubber. That brought it down to 14,300 pounds. The TIV 1 weighed approximately 14,000 pounds fully loaded. The Dominator 3 is the lightest of the three, though published figures disagree: The Drive gives 11,000 pounds and Wikipedia gives 13,000. Either way it is light for its armor rating, which follows from starting with a pickup rather than building a body from scratch.
The DOW is a different category. It is not armored and is not meant to be hit. Weight there is about carrying a radar rather than surviving one: the Center for Severe Weather Research gives 4,900 kg for the first-generation system, and DOW 2 came to 25,000 pounds fully equipped.
What are they built on?
Every one of these started as a production vehicle. The TIV 1 was a modified 1997 Ford F-Super Duty cab and chassis truck, with a body of 1/8 to 1/4 inch steel plate welded to a two-inch square steel tubing frame. The TIV 2 is built on a Dodge Ram 3500 that was strengthened and converted to six-wheel drive, with a 1/8-inch steel skin over the same two-inch tubing. The Dominator 1 was a 2007 Chevrolet Tahoe, the Dominator 2 a 2011 GMC Yukon XL, and the Dominator 3 a 2012 Ford F-350 Super Duty. The first Doppler on Wheels went onto a modified Chevrolet G30 flatbed. Nothing here was designed from a blank sheet, which is why the engineering interest is in what was done to them.
What engines do they use?
The TIV 2 runs a 6.7-liter Cummins turbodiesel modified with propane and water injection to produce 625 horsepower, and will exceed 100 mph. That matters more than it sounds: a vehicle that cannot outrun a repositioning tornado is a vehicle that cannot choose its intercept point. The TIV 1 managed 80 mph on a 7.3-liter Ford Powerstroke, which constrained where it could safely be. The Dominator 3 uses a close to stock 6.7-liter turbodiesel making around 400 horsepower through a six-speed automatic.
How do they anchor to the ground?
This is the real engineering problem. A tornado does not push a vehicle over so much as get underneath it and lift, so every serious intercept vehicle solves the same three things: get low, seal the underside, and pin to the ground.
The TIV 1 lowered four hydraulic claws into the ground. The TIV 2 replaced that with a three-stage sequence: lower the vehicle on air suspension, drop three hydraulic skirts to deflect wind over the shell and shield the undercarriage from debris, then drive hydraulic stabilizing spikes into the ground. The Dominator 3 does the same three things with an airbag suspension, a deployable wind skirt and its own spikes. The Dominator 1 had none of this, which is precisely why the Dominator 2 was built. The DOW instead uses hydraulic outriggers, which is a leveling and stability problem rather than a survival one, because it parks at a distance and needs the radar level rather than pinned.
How much did they cost?
Less than people expect. The first Doppler on Wheels cost roughly $50,000 to mount. Sean Casey listed the fully functioning TIV 2 on Craigslist in October 2019 for $35,000, and it was bought by storm chaser Ryan Shepard, whose team restored it and returned it to service. Build costs are a different question from resale, and the TIV builds absorbed thousands of hours of labor subsidized by IMAX production budgets that never appeared as a sticker price.
How much punishment can they actually take?
There is one hard data point rather than an estimate. On an episode of MythBusters, the TIV 2 was parked behind a Boeing 747 and subjected to 250 mph engine thrust, roughly EF5 wind speed. It suffered no ill effects beyond slightly bent anchoring spikes. At the earlier 160 mph run the driver’s door was pulled open, which sounds alarming until you read the cause: Casey had forgotten to lock it. The Dominator 3 is armored to about 200 mph. Both figures describe the shell and the anchoring, not the occupants, and neither is a claim that sitting inside one during an EF5 is survivable.
Where are they now?
The TIV 2 is in active service under Ryan Shepard's team, sponsored by Storm of Passion and Live Storm Chasers. The Dominator 3 remains Timmer's working vehicle and was rebuilt as the Dominator 3.2 in February 2026, with a Dominator 5 announced in July 2024 and not yet delivered. The DOW fleet has turned over. DOW 6 and DOW 7 have both been retired and replaced by DOW A and DOW B, which run alongside DOW 8 and the C-band on Wheels. The fleet is operated by FARM, the Flexible Array of Radars and Mesonets, affiliated with the University of Alabama in Huntsville and led by Joshua Wurman and Karen Kosiba.