Question

Hello. I will be very grateful for some help.
1) Do you think it is possible to say: "Heavy rain started / began", and if yes, is it "heavy rain" or "a heavy rain"?
2) Is it possible to say: "Rain started falling", and if yes, is it "rain" or "the rain"?
3) Is it possible to say: "there was heavy rain"?
Thank you very, very much.

Answer 1

1) Yes. Either is correct, but a heavy rain is better.

2) Either is correct.

3. Yes.