`  :I was there some years ago and they told us this. I'm not sure that rain actually falls - I doubt it very much - but I could imagine that water vapour might visibly collect up near the ceiling sometimes. The building is truly immense. I think ``weather system`` is an exaggeration rather than an urban legend. Anyway, the official line is that something meteorological does go on in there, even if it's only a bit of mistiness overhead. —   `