You might get it reduced, I doubt you will get it vacated.

I got a parking ticket because I didn't move my car for street cleaning day. I was literally in the hospital on prescribed narcotics because of a major issue with my stomach. I contested the ticket, provided proof that I was in the hospital and was unable to move my car for street cleaning day.

I was told I should've given my keys to someone and had them move it, then they reduced the fine - but I still had to pay a fine because of the ticket I got while I was in the hospital.