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.

piovere a catinelle, piovere a dirotto

raining very heavily

:
I can't go out now, it's raining cats and dogs!
Non posso uscire ora, piove a catinelle!
We had to cancel the picnic because it was raining cats and dogs.
Abbiamo dovuto annullare il picnic perché pioveva a catinelle.