Originally Posted by MyBoyPuck
If you ride first, put the water in a black colored bucket, leave it in the sun while you ride. Warm water.
I do something similar too. Just fill in morning and let it warm on sun. The problem is it doesn't warm much if the temperature is not very high (say, 70).
Bathroom and hot water in barn are not the options, because I don't have a "real" barn - just Amish-build run-in/stall combo. :)