Originally Posted by Jason Thompson

Two things strike me about the 'lightning' in the film.

First, it does not make a normal thunderclap, but it does make noise.

Second, when the crowd gathers round the place where it struck, Cruise's character picks up a piece of tarmac from the spot and, asked whether it is hot, replies that it is actually freezing.

This leads me to conclude that Spielberg made some attempt to address the lack of thunder by making it clear it was not ordinary lightning.

However, what everyone seems to be forgetting is that it is the product of alien technology. This is, after all, a sci-fi film. The lightning is accompanied by an electromagnetic pulse, which I am not aware is a normal effect of lightning. It also acts as a transporter beam, allowing aliens to 'beam' aboard their tripods (from goodness only knows where) and only leave a tiny hole in the ground. The absence of thunder is just one of a number of clues for the observers in the film that this is not a normal storm. Who cares why there is no thunder?

I do sometimes have to wonder why we spend so long dissecting such a minor issue when we quite happily sit back and watch alien war machines zapping people with a ray that turns people to dust and leaves their clothes intact!