UPDATE
Snowball is home and on antibiotics fo a UTI - bacterial infection. He was very swollen but not blocked completely and went on his own. We are sooo happy to have our boy back home. Thank you for all your purrs and comments. I will visit ya'll on Sunday after I get some rest!
I noticed Snowball sitting in the litter box this morning but nothing was coming out. I gave him a dose of antibiotic I had on hand and called the VET. I had not noticed any straining, small pee balls or anything before this altho he had a UTI in March of this year. Being very large and still quite feral, we had to lure him into the dog kennel cage rather than the cat carrier. He was very alert and curious on the way to the VET. They did get a urine specimen from him already and we will wait to see what that shows.
I still do not have a computer - I am borrowing a friend's laptop and it is slow going as I am not used to working on this! For pics I will have to use old ones I already have on other blog posts.
Please keep our sweet boy in your thoughts and keep those purrs coming!