a lorry driver that couldn't escape the rain

I think it was Douglas Adams, and one of the Hitchiker's Guide to the Galaxy books, Connie
(calling Max Quordlepleen!)
...though I may just be confusing it with another story where a lorry driver (or someone) is constantly being bugged () by flies. It turns out he is The Lord Of The Flies (but not William Golding's pig-on-a-stick) and didn't know it.

Ah! Is the other one a Terry Pratchett story? Quite close idea, though, as the lorry driver, it turns out, is a Rain God...

Edit: Rhuby beat me to the draw there!