People that have not been in the military can't really imagine what a MASSIVE explosion sounds and feels like. When I was young the Goodyear chemical plant blew up. We were a little over 20 miles away in a garage apartment and it shook like someone had rammed it with a truck. The low-frequency sound rolled in and the place rattled for several seconds.
This was back in the cold war days and there was no doubt in my mind what I was hearing. That is a sound totally unlike thunder. We bailed out of bed and looked outside for a bright light or something. When there was nothing near to us I honestly thought that it was either Houston or The petrochemical plants closer to the coast than we were catching a nuke.
At that time the area where I lived was ranked to be number 8 or 9 on the Russian target for a nuke in the US. The area was called "The Golden Triangle" and at that time we were the largest refinery area in the US. At one point about 60% of all the gasoline used in the US came from that area.
It was creepy as hell and we got dressed and headed out to my future wife's parent's house. As it turned out we ended up driving right by that plant when the second explosion happened. We were about a quarter of a mile from it and it still pushed my mustang across the road into the other side of the highway.
When we got to her parent's house there was some discussion about evacuating. A lot of those chemicals are not good for breathing. Even more concerning was that that area was sitting on top of HUGE natural gas storage under the salt domes and if those touched off you didn't want to be within twenty miles of it.