Here are some ways how science is misused in the movie Twister. In a real twister, air and debris goes in toward the twister not out. Debris, 18-wheel oil trucks, farm equipment, cows and houses being flung away in not possible. Tornadoes do wander and alter their path and change in intensity, but they don't go back and forth across roads and take sudden U-turns or drop out of sunny windless skies. Lightning and thunder don't flash and crash at the same time. Lightning is seen before thunder is heard so this is definitely not possible. Like I said earlier there is no way that a truck can come out of an explosion absolutely fine. In real life the paint on the truck would come off and the truck would be absolutely destroyed and have scratches on it but in the movie it came out absolutely new.
Here are some more ways how science is misused in the movie Twister. Another example is the last twister in the movie was classified as an F-5. Yet when it hits the farm where Jo and Bill are strapped to the pipe, about a third of the barn is still standing. F-5 level tornadoes will destroy steel reinforced concrete buildings, so the entire ranch, house, barn, and all, should have been swept down to the ground and destroyed. Another thing is that the chance that you survive a F-5 tornado is very rare. Flying wood splinters and glass at that speed can shred clothes and skin and cause a really bad injury.
Here are some ways how science was somewhat used correctly