I tried to look up what our term "isslag" would be in English, as it is when supercooled rain falls and freeze instantly when it hits the ground that is below freezing - i.e. the shade, bridges etc. where it most dangerous when it's just around freezing everywhere else, but the shade, bridges etc. just that bit colder.
Turns out it is merely "freezing rain" in English (sort of disappointed by that):
https://en.wikipedia.org/wiki/Freezing_rain
And the wiki-entry for "black ice":
https://en.wikipedia.org/wiki/Black_ice