I am between Baltimore and DC right now, and I just seen a horse carriage in barely 30 degree weather, isn't this a little cold for a horse to be out in and working?

Horses (as well as people) would be out in all weather in the wild, so why not? not to mention once it warms up its muscles it will be more than warm enough to not be a problem assuming the owner isn't mistreating it by running it then making it stand in the cold unprotected.

Horses, as are many other animals, are more equipped to deal with colder temperatures than are people. The people in the carriage were probably feeling the low temperature much worse than the horse!

Agreed, this was fine for the horse. They are not like us naked humans, they have hair all over their body which helps keep them warm, not to mention huge muscle mass that when in use generates a lot of heat for them.

I do believe that the horses are large enough and have enough hair to keep their body temperatures raised. I do not believe that extended periods in sub zero temperatures would be good though.

That would be interesting to see, I never really thought about horses staying warmer than us in cooler weathers. Does that mean they are always hotter in the summer and how would you cool them down?

Is there anytime weather wise a horse shouldn't be working, besides like sleet or something that is, maybe hail too thinking about it. I really thought it was too cold out but I guess that horse didn't mind at all.

I think it would depend on the exact conditions. If the weather wet the coat and kept it that way with a wind it would chill the horse quickly. Same with strong wind thats cold. But animals that are out in the weather more grow a thicker coat thats pretty good at insulating. They shed it in the spring/summer so they won't overheat.

I couldn't feel comfortable having my horse out in the elements even if I felt it could manage it. When I consider my economic investment and the relationship between my horse and I, my horse would have to be treated as one of the family.