The first of the 4K movies that has been posted online presents one of over 2,000 nuclear tests that have been made around the world from 1945 to today. In this case, it is material presenting the Upshot-Knothole Grable explosion of 1953.
Other of the interesting recordings from the YouTube channel, where archived recordings are placed, presents American tests of nuclear weapons on various types of vehicles. Take a look:
You probably wonder what you see in the above movie and what happens to the cars before the sound wave arrives. It is a thermal shock wave, which, together with a radiation wave, is able to "dry" the paint on vehicles in a flash. Only after it comes a sound wave.
You can watch other recordings of the explosion on the channel AtomCentral on YouTube.