I do my own blanketing, as my horse is in a 24/7 pasture situation, and her pasture is enormous and on the back of the farm, so it isn't feasible for the stablehand to have to do that every day, as my board really doesn't include that anyway. It's a 5-10 minute walk from the barn if she's at the far end, where she usually is, and there are nearly 30 other horses needing attention on the farm.
This is how I do my blanketing. I blanket with a waterproof sheet 60 and below. And she will look at me like I'm nuts if I don't put that sheet on when I put her out if there's rain in the air, or if it's chilly, but that's just her. She hates being stalled, but she doesn't like any sort of less than perfect weather without something on. 50 and below I use her medium/lightweight turnout blanket. 40 and below I use both.
Cinnamon Whiskey 11 y/o 15hh Chestnut AQHA mare, 2'6 Jumpers