During today's blizzard here in Nebraska, I saw this frost pattern on an east facing window of our house. It is about three inches by three inches in diameter. I set my trusty little Nikon on macro and waited for the best lighting conditions throughout the day, then took the photo in the late afternoon. Outside air temperature: four degrees F. above zero.

Nikon Coolpix S9500

Cropped and adjusted color using Windows 10 editing software, then sharpened in GIMP.