Learn Portuguese (Portugal): Hoje faz muito calor.

In Portuguese, we often use the verb fazer (to do or to make) to talk about the weather. Literally, this sentence translates to 'Today makes a lot of heat.'

Why is there no word for 'it' before faz?

Unlike English, Portuguese does not use filler subject words like 'it' for the weather. The verb faz stands completely on its own to express 'it makes.'

Does calor mean 'hot' or 'heat'?

Calor is a noun that means 'heat'. Portuguese describes the weather as making heat, rather than being hot. If you want to say food or a drink is hot, you would use a completely different word: the adjective quente.

Why is it muito calor and not muita calor?

Because calor is a masculine word (o calor), the word for 'a lot' or 'much' must match it in the masculine form, which is muito.