English slang for describing a heavy rain

Some English slang for describing a heavy rain is very interesting. One of them is 'raining cats and dogs'. You can imagine how bad the rain is by picturing the scene in your mind. Another one is 'hosing down'. It's like that God is hosing down the water to our world from heaven. 'Hose down' also means to shoot someone with a gun in American. Well, we don't have a lot of guns in New Zealand. So when people use the phrase 'hosing down', they usually refer to the weather. What other interesting slang do we have to describe a heavy rain? ;)

I usually say "it's pouring" or "it's pouring rain" (I was born in Kentucky in the US, and we had a lot of heavy rain).