A couple of days ago I let my cat out after work as I normally do. He was doing fine as I watched him walking around the yard. But he didn't come home that night. I thought maybe he got locked up in someone's garage or shed. The next morning when he didn't show up I went looking for him. I found him lying on the ground in a neighbor's fenced in yard. When I went over to him he was frozen stiff. I wrapped him in a blanket and brought him home. I desperately tried to warm him up with blankets and a heated throw. I thought I heard a few grunts which gave me some hope. I couldn't understand how a 20 lb cat could freeze in such a short time. It wasn't below freezing outside. I ended up taking him to an ER vet at the suggestion of friends. It was too late. Jack was gone. I asked if he could have froze to death and they didn't think that was the cause. They said he could have had a medical issue such as vascular that I didn't know about. How could that be? He was acting fine before this. I'm sorry for the long post but I'm trying to get some closure without having an autopsy done.