English Experts

[Alessandro]

Português: chuva forte / chuva pesada
Inglês: heavy rain

Exemplos:

1. Flooding caused by heavy rain in south-eastern Brazil has forced more than 9,000 people to flee their homes, civil defense officials said on Saturday.
2. Dozens of people died as heavy rain caused flooding and mudslides in Brazil this week.
3. Heavy rains and landslides are not uncommon in the mountainous area of Rio de Janeiro state.

[Thomas]

also...

very heavy rain
a gully-washer
a cloudburst


very light rain
sprinkle
mist


The storm last night was a really gully-washer. The skies opened up and we had a real cloudburst that washed away a bridge.

It didn't rain yesterday; it just sprinkled for about ten minutes. You might say it was just a mist. There was no damage at all./

[EugenioTM]

Another ways to describe a heavy rain:

pouring rain
to rain cats and dogs
to pour down

Examples:

What if it starts pouring the rain?
Urban dictionary

The rain poured down on us, soaking us to the bone.
Urban dictionary

It was raining cats and dogs. (LOL)

[rafaelsgarbulho]

Raining cats and dogs

Of course in a very slangy informal way, not dirty though

[pondedaniel]

raining 'zoos'

[Adriano Japan]

*Adding:

downpour
rain in torrents
rain cats and dogs