What weather conditions heat does your horse have need of to wear a coat /rug and what season do u metamorphose them?

My honest answer is that most horses do not need a winter blanket,whether that's what you're asking. Horses are built for surviving cold weather,and if you've ever seen a horse's winter coat,you'd be positive.:) If it's going to be below -10 then I'd definately start thinking around it...Horse blankets do cut down on hay intake too. The hay gives the horses the energy to stay warm,but whether they're not using as much energy,they'll eat less. That's another thought. After around January/February I'd bring the blanket off. To add onto that. Older horses and younger horses would be more likely to obligation a blanket than a middle aged horse in perfect condition.
It depends on the breed of horse as say a thoroughbred would entail warmer rugs than a cob type. Also it depends on if the horse is out or in a dark. As a general rule you would have no rug on if it's exceedingly hot and mild (summer usually). You would use a summer sheet or light weight rug whether there is cold showers but the weather is about 15 degrees. Once it get into really cold winter you would put on a heavy weight rug when the horse is outdoors. At night whether the horse is kept in you can put a thin fleece rug on when it starts getting chilly and then a pad stable rug in the middle of winter.
My horses are usually out short blankets through the entire winter months. I live in WI so it can get sometimes below 0. If there is a snow storm or its extremely cold, more than 5-10 below I will blanket. Most of the time though I will maintain them inside or at least allow shelter in below zero weather. Once the horses are used to the weather they can switch it and are very hardy. But if you shipped a horse to WI from Texas or somewhere down south, you would have to blanket probably at 30 degree because they aren't adapted to the weather.

As far as rain, I don't blanket or put a sheet on them. I always have a run within shelter for my horses even when its not raining. But actually my horses are always outside standing within the rain...Even in a down pour of rain. They would fairly be outside grazing than worry about getting out of the rainfall. Most horses I know are the same way. Rain doesn't bother them much.
The coat comes twice a year natural beside a healthy horse, like a dog or cat, horses don't need a blanket/rug unless they are surrounded by work. As long as a horse can get out of the wind and rain whether desired, there is no reason to blanket a horse that's not in work. The with the sole purpose reason I blanket my horses is it takes longer for a horse with a full winter coat to dry than one that have been blanketed.

For blankets I go by the simple rule for ever 5 degree Celsius the warmth drops, add 100grams of insulation to the blanket, this is any time of year.
above 15 C (if windy or raining) a simple rain cover, no nourishing
15-10 C(59-50 F) 100gram
10-5 C(50-41 F) 200gram
5-0 C (41-32 F) 300gram
bellow freezing 400gram
You don't have to buy one of each gram of insulation, a horse can be turned out with 2 blanket, one lower than the other, to achieve the desired insulation. If you don't work your horse as much and want a thicker coat, simply drop the list 5-10 degrees so you start at 10-5 C near 100grams :) The blanket should be removed daily and the horse brushed to remove dirt or the blanket might rub. I always stick with marine proof blankets as I'm not always home to get the horses contained by if it rains.
My horses never wear them. they are out with a run surrounded by shelter all year round, in all weather which get down to 30 degrees below 0 F, and still choose be be outside of the shed most of the time.
I have never blanketed any of my horses, and I am up contained by Northern BC Canada, and it can get cold up here every once in a while. Wild horses don't get blankets, my horses, are feed better than wildies and they don't have to paw for food (thus burning off precious insulation AKA fat!) They grow within a full winter coat, and that is good IMO. And yes, I am riding them, they will stay in a drying/cooling barn for a bit whether they really sweat up while working, and then they outside. My wife on the other hand blankets hers (she have a different up bringing than I did) as soon as the weather gets around 0 degrees C.
Answers:    It has to be around 0 & then shivering for me to blanket . Horses are made to endure the weather. Wild horses don't carry blankets. & They live.

Mine also only have a run in. Mine are surrounded by WY & they don't get blankets there, 151 acres.
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