frost flower

It has cooled down for a few morning.
That day was -20°c.
Temperature will stay low for a while.
This weather show us “Frost flower” at the lake and river and swamp and puddle.
The conditions to make frost flower needs -15°c, no wind , no snow and thin ice.
To fulfill these condition, you will see frost flowers.
But it is hard to see that frost flower spread across a wide range.