How do “Jack Frost designs”
get on windows?

You can see that the frost on a window is always on the inside. And if the outside temperature warms up, or maybe if a window is right in the sun, the frost may melt into water that runs down on the inside of the window. So, you can see that the frost is made out of ice that formed on the inside of the window.

Frost forms on a window when the temperature outside is below freezing. Inside it is warmer, and there is more water vapor in the air. Any water molecule in the air that hits the glass will stick to the surface. As it sticks, it is hooking up to other water molecules to form ice crystals.

Every water molecule is made of one oxygen atom and two hydrogen atoms, H-O-H. Water molecules can stick together by sharing their hydrogen atoms. They tend to make six-sided shapes but in all kinds of patterns. The really amazing thing about frost on windows is that it forms in such varied and beautiful patterns. If you were wondering why they make some of the particular Jack Frost patterns, I just have to say that I do not know.