In use: There is a 40 per cent chance of precipitation this weekend ... Frost/hoarfrost [hor-frost]/rime Frost is ice that forms because the air is cold. Hoarfrost and rime are very similar.

And that can occur even if there's no precipitation. Freezing fog basically ... pleasing effects of freezing fog is the formation of rime, deposits of interlocking ice crystals caused by freezing ...