I'm wondering if there are those with more 'experience' with close strikes than I who may comment. I had a very scary time during an old fashion midwestern frog strangler that happened when I was in late grade school. I was the only one home in the afternoon when a nasty storm blew in, and while not gusty was full of spark and energy. Our farm house was surrounded by old cottonwoods about 40-60 feet high. There were repeated strikes close by (but we didn't loose any trees) and I literally went into the middle of our living room and squatted down, not knowing what else to do. Most of the strikes were incredibly loud, one right after another for a couple minutes, but the really close ones had more of a sizzle and an sensation of sound and pressure rather than an explosion boom to a few of them. The laundry was done immediately after the storm moved on. No tornadoes, but just a short incredibly electrical storm.
On another event when my brother and I were in his International Scout going to a field it began to rain so hard that we had to pull off on the side of the road, just impossible to see the blacktop and no lines other than a center line which was obscured by blowing rain. Our two way radio in the truck would begin with a high pitched squeal, rapidly decrease in frequency followed by a close strike that shook the little truck like being hit with a very strong gust, but it wasn't just the wind. That happened a few times, and sure made us stay inside and with the windows rolled up, away from the doors as best we could. The farm land was as flat as a table for miles in each direction, with only a trees in windrows, so we were the highest thing around for some distance, but our truck never got hit. Just the 'warning' squeal from the radio.
Maybe I've told the story before, but a neighbor had been out in his field with a tractor pulling a big disc (can't imagine a better ground to earth with all those metal blades dug in the ground) when his tractor (no cab on it) got nailed on the muffler sticking up. Blew the tires out and while he wasn't injured, it knocked his pipe out of his mouth and stopped the tractor from running. I think he did find the pipe after he got off. It wasn't raining at the time, but sort of a bolt from the blue. The odd thing now that I reflect on that, is his tractor was a diesel, with no electricity needed to keep it running, a mechanical fuel injector pump with a gravity feed fuel flow to the pump, so why it quit I have no idea. I don't recall it affected his nerve too much and he continued once the tractor was fixed later on.
My dad recalls being in the hay mow of a barn when a tornado went through, him seeing trees a short distance away being knocked over and twisted. The barn or silo got nailed by a strike while he was cowering in the middle of the hay mow, and he said it was more of a feeling and sizzle rather than a loud noise, so I wonder if the expanding air hadn't gotten a chance to develop a wave front yet?
Does anyone know about really close strikes and if you can hear them or if you have to be a hundred feet away or more before the sound develops?
Dale