I know how you all feel too.The momma comes out in us all when it comes to our critters. The weather is real simuliar up here in WA. Very windy and that's what worries me.My horses have a shed and blankets on. Their feet and manes have a few icicles on them brrr.
I went around this afternoon and winterized everyone...closed my emus door and trapped them in the barn to keep them out of the wind.I even wrapped up my rabbit hutches real good so the snow wouldnt blow thru their cages.Had to keep giving them water because it keeps freezing.Moved the chickens water inside their house, they wont come out, too cold on their feet I guess.
I worry bout the horses water too, keep breaking the ice(wish I had gotten the water warmer).
The only one here that likes the snow is the dumb dogs!
Good luck dear, Im sure if your horse has got the winter hair and some shelter it'll be fine.