When the weather starts to cool off, and temperatures start to drop, most horse lovers start to worry that their horse might need a blanket. And rightly so. There are discussions that question the need for any kind of blanket as the horse’s winter coat naturally insulates the horse’s body by trapping air, keeping him warm. With proper shelter and enough of a winter coat, horses can be comfortable without a blanket in colder weather. However, rain in particular can cause the horse to get cold, as it lays the hair down, flattening the protecting air layer, and destroying its natural insulation ability. Wind will also penetrate the coat, robbing the warmth from the horse’s skin and body.
Most horse owners can’t bear the thought of their horse being cold at night. At the very least, they feel the need to keep their horse warm and dry, protected from the elements. Visiting your horse in the evening when it's chilly and reaching under the blanket to feel the warmth is worth all the effort of selecting the appropriate blanket for the season. Pulling off a muddy blanket to reveal a clean, dry coat that is ready to ride with just a couple of minutes of grooming is also why we blanket.
Ideally, it is practical to have at least three blankets. A no-fill waterproof rain sheet, like a windbreaker, for those windy, rainy but not really cold days; a light to medium weight waterproof blanket when fall and winter weather start to get cold, and a heavy weight one for the coldest weather. How heavy your blanket should be depends on your area’s winter weather and how thick your horse’s coat is. If you clip your horse for the winter, or he’s old or a hard keeper, it’s a no-brainer: your horse needs a blanket.
It’s a bonus to also have a fleece cooler to use after hosing off or sponging your horse, or when caught out in the rain, or when you’ve ridden hard enough to work up a sweat. If you put a blanket on a wet coat, your horse can get chilled. So dry him off with towels, roughing up the coat to allow air to help dry it. Throw on the cooler to help wick away moisture and walk him to generate some heat until he dries. Then put on his blanket.
Take the time to measure your horse, and get a blanket that fits properly to avoid rubbing if it's too small or avoid slipping side to side if it's too big, or heaven forbid, big enough your horse gets it off. Leg straps are a must to help the blanket stay put. The well-known method of measuring the horse from the center of the chest, along the side, to the center of his back legs works well. Although it takes time, when it gets muddy, brush the mud off the blanket with a stiff brush to help it keep clean through the season. It’s easiest to brush off the dried mud while the blanket is on the horse
Choose a blanket with the amount of fill, or grams of insulation, you need to keep your horse healthy and cozy. Zero fill is a lightweight day or rainsheet that can be used in mild weather throughout the year, like a windbreaker. 100 - 200 grams is light to medium weight, and 300 grams is heavy weight for really cold weather. If your horse has sweaty patches when you take the blanket off, it’s too heavy. If he feels cold under the blanket, it's not enough. Ideally you should monitor your horse and remove the blanket daily to check on his condition.
You are the expert when it comes to keeping your horse comfortable. You will know if he’s cold, or too hot. It might be 40 degrees and your horse has a reasonable coat, but wind and rain are such that he needs a blanket to stay warm. With several blankets for different weather conditions, you are prepared to keep your horse toasty warm throughout the year.
It’s easy to choose the perfect waterproof blanket with the appropriate amount of insulation for your horse in all seasons and a fleece cooler at Grewal Equestrian.com. - https://www.grewalequestrian.com/collections/blankets-sheeting