Cats and Dogs

[curious81]

Why do we say it's raining cats and dogs?

[jno]

because you might step in a poodle?

[THECORBYLOON]

Cue groans and the hurling of rotten fruit and vegetables...

[rojash]

In earlier times they used to say it's raining cows and bulls, but so many people were seriously injured in rainstorms that they changed it to cats and dogs. The health & safety executive want to change it to "it's raining feathers and small bits of fluff".

[heathfield]

A popular explanation is that it's from the Latin 'Cata doxus' which translates to 'beyond normal experience'.

I heard a different explanation years ago, which I can't fully remember. It referred to something along the lines of 'cratora et doga', which seemingly meant 'buckets and vases'.

[jno]

http://www.worldwidewords.org/qa/qa-rai1.htm

[twilightflye]

because it pelts it down

[treacle_a]

A thatcher told me this a few years ago. Apparently the actual reason is that back in medieval times domestic animals like cats and dogs would sleep in the thatch of the house to keep warm. When it rained very hard it drove them out of the straw.

[VS Prasad]

This is an interesting phrase in that, although there's no definitive origin, there are several speculative derivations.
The phrase seems isn't related to the well-known antipathy between dogs and cats, which is made word in the phrase 'fight like cat and dog'. Aside from the presence of cat and dog in the phrase, there's nothing at all to connect their fighting with raining.

Nor is the phrase in any sense literal, i.e. recording the fact that cats and dogs fell from the sky. Numbers of small creatures, of the size of frogs or fish, do occasionally get carried skywards in freak weather. That must happen to individual dogs or cats from time to time too, but there's no record of groups of them being scooped up in that way. Not that we'd need meteorological record for that - it's plainly implausible.

In fact, 'raining cats and dogs' only makes sense figuratively and the explanations below that attempt to link the phrase to felines, canines and weather seem rather feeble.

http://www.phrases.org.uk/meanings/raining%20c ats%20and%20dogs.html

[smeghead81]

'cos we Brits are stupid thats why