I have noticed hard frost images before on our car parked overnight in the drive. The car is on a slope facing upwards towards the south and the frost pattern seems to emanate from the high point of the roof, which is towards the higher front end.
Here is a closer view of the roof.
The pattern on the roof of the car reminds me of the view from a plane when flying over the Alps.
A very close view shows the granules of frost making up the effect. This is the apex of the car roof and I presume that periodic melting had occurred followed by new freezing.
As the sun hits the roof it highlights the pattern and eventually starts to melt the frost around its edges. A pattern similar to a fir tree starts to emerge. The melting starts from the high end establishing the bottom of the trunk of the tree and begins to form the outline of the rest of the tree.
Making the photograph darker produces the effect shown at the top of this post.
I prefer to leave a bit of the car in the photo myself, but here is a view without the top of the car windows.
I am fascinated by intricate decorative patterns appearing in nature. Sometimes my Single Continuous Lines include a hint of this naturalness.