I've never heard that construct. Are you by chance referring to Morton Salt's motto "When it rains, it pours"?
I think it was HN that lead me to the discovered not too long ago that the phrase originated from an early-20th-Century ad campaign of theirs following the introduction of magnesium carbonate, an anti-clumping agent: https://en.wikipedia.org/wiki/Morton_Salt
No it is a colloquial saying in Britain, especially in the North of England. Me: "I hurt myself at work, then I lost my wallet and my girlfriend left me", Someone else: "It never rains, but it pours".