We use this idiom to say that it is (or was) raining VERY heavily. (It doesn’t mean that cats and dogs are falling from the sky!)
1. The weather was horrible on Saturday. It was RAINING CATS AND DOGS all day.
2. It’s awful weather outside. It’s windy and is RAINING CATS AND DOGS.
3. It was RAINING CATS AND DOGS, so all flights were cancelled and I could not reach my native town in time to join the marriage ceremony of my brother.
4. There’s no way they’ll be playing at the park. It’s RAINING CATS AND DOGS out there!
5. It’s RAINING CATS AND DOGS, so make sure you take an umbrella with you.
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