"wasn't" or "weren't" with weather

Question

Which is right:

"I'm fed up with this weather. I wish it wasn't so hot."

or:

"I'm fed up with this weather. I wish it weren't so hot."

Answer 1

First it's worth mentioning that weather is non-count so it must be used with a singular verb form as in

The weather turns bitterly cold at night.

But it's not the countability of weather that makes us choose were over was here; it's the matter of mood.

Since the idea of your statement is expressing your attitude towards the reality of the state of weather here (subjunctive mood) and you want something (not) to be true although you know it is either impossible or unlikely, it's recommended by traditional grammar rules to use were and not was. Although both are used nowadays interchangeably so I can't really say was is wrong here.

Other examples could be

I wish it were a lie that she stole from me.

He wished Emily were with him.

Source: Which is right: I wish it were… or I wish it was…?

Also for additional information and getting a grasp of using past form of verbs in this mood see 'Past Subjunctive'

Answer 2

You can think of it this way:

weather

is usually referred to as "it"

Today it is cold

so, the singular be verb gets used

It was cold today.
I wish it wasn't so cold.

I wish it weren't so cold today.

is still understandable.

Answer 3

Both the sentences are grammatical.

In case of a hypothetical or nonfactual situation, you can use the construction subject + wish + singular noun/pronoun + was/were.

However, the use of the subjunctive "were" is more common.

Answer 4

After wish, the verb to be, in formal grammar, would be: I wish it weren't. That said, I wish it wasn't is also acceptable.

Compare this to: I wish I were rich. I wish I was rich. Both are OK, some nitpickers would not accept/ I wish I was rich/ and would insist on /were/ for first and third person.

If he were rich, he would buy me a diamond ring. [unreal condition, formal] If he was rich, he would buy me a diamond ring. [also unreal, acceptable but not formal]. This use of were is called "subjunctive".

Otherwise, after wish: I wish I had a diamond ring. I wish you worked late. I wish you would shut up. I wish they would leave. I wish they had left. I wish they had arrived on time.

Wish + action verbs = past perfect for something in the past or past condition meaning future.