Related, may I ask in what climatic area are you living? Where I live it gets so cold in the winter that I almost can't even wash my hands with cold water.
On the other side I feel like in the summer I could take on such a habit. Maybe a solution would be to warm it just slightly in the winter.
Hands are also the hardest part of the body to cold-shock, all those little bones and large surface area. People who routinely go into ice baths often keep their hands above the water so they can stay in longer.
Not really, it just more pleasant to take a shower with less of an impact after. Summer is easy, it's the cold winter that counts :)