Mustangs live in many different climates. They can handle almost any weather.
I keep my mustang in the garage
do they live up in the mountains or in the wild are they wild horses or are they just horses that live on a farm with there horse friends.
Warm Climate
Horses can live in almost any climate. For example, Arabians are found in Africa and Asia where it is very hot and sometimes they even go out to the scorching desert. While the Icelandic pony lives in the far north where heavy snow fall occurs every winter. A horse is bred for a certain use and there use will revolve around its climate. Again, the Arabian has a light, sleek coat to keep itself as cool as possible in the hot weather and the Icelandic pony has a thick, shaggy coat to keep it warm. If your talking about a horse in Britain or Ireland then will already be used to the climate there if they were born there. The case would probably be different if you brought a foreign horse that has spent most of its life in a very hot or cold country to Ireland or Britain.
in hot weather
No. Climate is weather and weather brings rain. Without climate there would be little water and all the crops would die.
Western U.S., cold mountains , dry deserts, and Northern U.S. .
They live outside, so unless you live in Antarctica you should be good.
Warm tropical weather
There are a few hundred Mustang Horses in Alberta and British Columbia. In North America, more than half of the living population of free-roaming horses live in Nevada, with the rest of the population spread among Montana, Wyoming, and Oregon.
Mustangs live on grasslands. Their history dates back 55 million years, and their coats usually help them to blend in with the grasslands. Many live in the western United States.
You can adjust to the climate of a mountain to live on top of it by staying warm when cold weather comes (such as building a fire).