if + were/are in conditional

Question

#1 if you are tired tomorrow, you won't have had enough sleep

#2 if you were tired tomorrow, you won't have had enough sleep

I know the difference, but can I use #2 in daily life? and is it grammatically wrong to use #2?

Answer 1

The second doesn't make sense.

It seems to be a "counterfactual" or "third conditional". It means "You were not tired tomorrow, but let's imagine that you were".

But you can't make counterfactuals about the future (unless you have a time machine). That's why the third conditional uses past and past-perfect.

So the second is not possible in sensible English.