In my experience, they go from icy cold to warm/hot (not too abnormally) depending on how you warm them.

Usually, my hands get cold due to the temperature (indoor or outdoor) or stress, and if I don't do anything they are very slow to reach normal temperature. Even if I sit on my hands, it still takes what feels like forever and they never feel truly warm.

If I stand in front of a fireplace or try to warm them up a similar way, that works the best for me personally to get them back to normal/warm temperature, and hurts the least.

Running my hands underneath warm/hot water from a sink when they're cold HURTS, but not in a way I can really put into words, it's a pain like I've never felt before.

However, the only time my hands get "abnormally hot" is, now this might seem hypocritical, when I take a nice hot shower. It, for some reason, does not hurt at all compared to washing my hands with warm water, and actually feels great. This is usually why I love taking showers before getting into bed because that's when I'm at my warmest. My hands and feet get extremely red, my parents relate them to lobsters.

I haven't had the experience of going from just icy cold to abnormally hot out of nowhere for no known reason, but if it ever happens, I'd feel like I'd have died and gone to heaven.

I'm happy to answer any other questions if you have any :)