I wish!
What's the difference between these two sentences:

I wish it rained.
I wish it would rain.

Question

I wish!
What's the difference between these two sentences:

I wish it rained.
I wish it would rain.

Answer

I wish it rained is now in the present.
I wish it would rain is in the future.
Maybe you would like to take a look at this page: 
http://www.englishexercises.org/makeagame/viewgame.asp?id=5841
Keep up your good work in learning English!

Answer

I would say
I wish it had rained - past tense
I wish it would rain - present and future

Answer

'I wish it rained' is not correct grammar.