Watery eye

My dogs one eye has recently been watering excessively. He seems to be squinting more in that eye as well so I think it may be sore, or it could just be bothering him. I was wondering if there is anything that I may be able to do to help him. I don't know if maybe he got something in it and it's agitated or what. Would putting a warm cloth on it help? I know that normally would draw out anything from they eye.

[Aleda M Cheng, D.V.M., C.V.A]

He could have a corneal ulcer, corneal foreign, conjunctivitis, uveitis, or other eye abnormality.  He would be best to have his eye examined by your vet.