Rain/water droplets are coming in through the window

Question

It's raining heavily outside and a window was open, so if the action" of closing has to be explained by using the rain that is falling into the house through that window, what will be used?

1.)The rain coming in through the window.

2.)The rain is coming in!

And if it's just drizzling and only a few water drops make it into the house through the window, will still rain be used?

3.)The rain is coming in.(through the window)

4.)The water drops are coming in.(through the window)

So what sounds natural? And can "through the window" be dropped and simply "coming in" be used in all of the sentences?(all the four sentences)

Answer 1

No.4 does not sound natural, but could be a little better if re-arranged: Drops of water were coming in ... but only if rain/drizzle/etc. was adequately implied by the context.

No.2 is fine, but the in the No.1 and No.3 is un-natural, better would be:

(3) Rain is coming in.

(1) Rain is/was coming in through the window