With a record-breaking tornado season already underway, Josh and Sean race to get the new DOW6 and the bigger, badder Tornado Intercept Vehicle, TIV2, on the road. Reed, meanwhile, has been chasing for weeks, already surviving a harrowing near miss and a hailstorm that takes out the TVN's windshield. The DOW and TIV finally get out the gate, but it's the SCOUT team that faces the first big challenge -- a dangerous night chase.

The crews of both TIV2 and new DOW are tormented by mechanical problems. Aaron and Danny in the SCOUT get clobbered by a massive storm as they head out on their own. Reed and the TVN crew are chasing down a huge storm as it bears down on Lamesa, TX, and are almost hit by lightning themselves.

The contest of wills have been heated up between Sean and Josh Reed due to missed sightings and vehicle problems. A little envy and a brief mutiny is sparked when Reed and his fast-moving crew make a brief rendezvous with Sean and the TIV. Reed chases a tornado in the dangerous hills of Arkansas at night, while Sean and Josh return to Greensburg, Kansas one year after an EF-5 nearly wiped that town off the map.

The TIV1 team is back in action as they approach the halfway season for storms, and head first towards Oklahoma and then to Arkansas. The vehicles forge ahead despite a monster hail storm battering the fleet as tornadoes begin their touchdowns all over the Great Plains. Everyone is prepared for a feast of tornadoes, but once dark hits the twister chases the chasers into the streets of Stuttgart, Arkansas.

Josh scrambles to fix the broken radar which has sent the DOW team in chaos. Reed uses this as an opportunity to get a step ahead of the science team once again, while a tornado bears down on Danny and Aaron as they struggle to escape from a ditch.

All the teams are hunting around the same area as rival TVN, now that DOW and all the chase vehicles are up and running again. There are tornadoes forming all over western Kansas, which may become the season's biggest day.

While roaming Nebraska, Reed and Josh' teams are struggling to find that perfect storm. Jene, Reed's girlfriend, becomes lost in a deadly hailstorm while the DOW team finds themselves driving straight into an oncoming tornado.

With tornado season winding down, Sean is getting close to his last chance at taking a shot from inside a tornado. Meanwhile, Reed pushes his team as they come closer to a twister than they ever have been before.