In addition to brutally cold temps, sometimes those blasts of arctic weather bring unexpected gifts — like the ones that covered an entire Minneapolis lake this past week.
“Frost flowers,” or ice crystals that form on water in certain conditions, were spotted in abundance on Lake Harriet — a rare occurrence that’s typically only seen on sea ice.
The “blooms” were initially spotted Thursday by the Water Quality staff of the Minneapolis Park and Recreation Board, the agency said in a Facebook post:
The Parks board says these delicate clusters form on top of newly frozen ice “only when it’s very cold and the air is very still.” and typically do not last long as they are easily damaged by wind.
“It’s been has been years since we’ve had anything close to the right conditions for frost flowers like the ones that formed yesterday,” the post says. “The ice must be very fresh so it is still close to the water temperature and the air must be at least 20 degrees below freezing and the calm for crystals to form.”