My long hair cat would do this in summer too and even liked it if we gently turned the faucet on. You mentioned it's winter where you live OP so this really is for north of equator where they are facing record breaking heat waves.

Another tip for having cats in hot weather: cold wet washcloths and just groom them with it. In my experience with like... 3 cats even it it is wet enough to wet their fur, they will still tolerate and like it in the heat if you do it in grooming motions. I've also frozen wet washcloths and used them as some sort of bedding option by placing something over it, petting them with it,, or just gently pressing it on some key spots on a cat that would help them feel cool such as below back of ears, spine, forehead, shoulderblades, neck, and especially cheeks/side of face/neck. When they are hot, they appreciate it or tolerate it enough. Know your kitty's body language.

Cats don't really sweat so help yours however you can during this heat wave.

Shit also sorry OP ruby is beautiful and I did enjoy the pic it's just my overwhelming instinct must be to lecture--- I mean share helpful tips with people. :P