If you've ever gone outside really early on a cold day in fall, you might have seen a thin layer of sparkly ice crystals covering everything! That ice is called frost, and it can only form if the weather is exactly right! ///Next Generation Science Standards Used in This Video/// K-PS3-1. Make observations to determine the effect of sunlight on Earth’s surface. K-ESS2-1. Use and share observations of local weather conditions to describe patterns over time.