It's raining cats and dogs

US /ɪts ˌreɪnɪŋ ˌkæts ənd ˈdɔɡz/
UK /ɪts ˌreɪnɪŋ ˌkæts ənd ˈdɔɡz/
"It's raining cats and dogs" picture
1.

土砂降り, 激しい雨

raining very heavily

:
I can't go out now, it's raining cats and dogs!
今すぐには出かけられない、土砂降りだ
We had to cancel the picnic because it was raining cats and dogs.
土砂降りだったので、ピクニックを中止しなければならなかった。