What to do?

I came home about 30 minutes ago to find a kitty (about 6 mo) on my deck. It is 26 right now and expected to get down to 19. The poor lil guy looks to be healthy but clearly scared to death. I was able to get him(I think) to come to me and he is quite a lover but pretty jittery. I cannot bring him in DH will have a cow and its not a good idea to expose my other 3 to whatever he may or may not have. I put some food and water out and a box with some blankets. He sniffed the food but only wanted attention while I was out there. As soon as I headed for the door he went to the food.Will he be ok with the box/blankets? I am half sick worrying about it...