Frazil

From Glossary of Meteorology



frazil

(Or frazil crystals;
also called needle ice.) Ice crystals that form in supercooled water that is too turbulent to permit coagulation into sheet ice.

This is most common in swiftly flowing streams, but is also found in a turbulent sea (where it is called lolly ice). It may accumulate as anchor ice on submerged objects obstructing the water flow.