estar por llover/estar para llover

Question

Here we learn 'estar por llover'It's only a couple of weeks since I learned 'estar para llover' and I can't tell the difference.

Answer

Hola JillYes, in the case of llover, as we explain right after we show that example in the lesson, can use both por or para to express the same "to be about to start raining". I would say that estar por + infinitive generally has the extra nuance of something about to happen but when there's been some thought involved so something is about to happen because you've just taken the decision to do it.  Estar para wouldn't necessarily imply this. SaludosInma