How the snow/ice patches in mountain biomes are calculated?

Solution 1:

basically how ice forms is that where ever it snows water will be valid for turning into ice and (eventually) Freezes.

there is no way to know where snow/rain will form in the world because it is random and even if somehow you were able to make a predicter then this dilemma will occur: before you make a world. there is no information to test/predict off of, and after making a world it is MUCH faster to just go or Teleport to the area to check if it has snow on it.

so the answer is It's Random But it has brackets so like if you were in an ice spikes biome the chance is 100% if you were in a mesa biome the chance is 0% and if you were in the base of a snowy mountain the chance gradually becomes better as you scale(go up) the mountin