The Journal Pioneer
The week got off to quite a start. Monday was one of those days when our precipitation couldn’t seem to make up its mind. Many of us experienced the gamut: snow to ice pellets to rain then back to snow; there were even reports of freezing rain.
As I admired the patchwork of pastels on the radar screen I remembered a letter I received earlier in the fall about one type of fairly unique precipitation.
Derrick DeZeeuw wrote, “I came home the other day and I thought my roses were covered with some kind of insect, but no. I have never seen tubular snowflakes before. Thought I would share this with you.”
I’m glad you did Derrick.
The life of a snow crystal of snowflake begins with nucleation around a dust particle. The crystal slowly grows to a hexagonal prism. As the plate gets larger it becomes unstable and grows little arms at each corner; that’s why most snowflakes are six-sided columns. The columns may be short and squat or long and thin – the long thin columns or needles tend to be more pronounced when the temperature is around –5 C. The needles can be solid, hollow, or partially hollow, depending on the temperature and moisture profile of the layers of air above the ground.
Now if the delicate ice crystals encounter strong winds on their way down, the tiny arms can break off… falling to the ground as little needles.
Did you know that sometimes – albeit it, rarely – the columns or needles are twisted? Twisted columns are also called Tsuzumi-shaped snow crystals.
Derrick – I’m glad you asked!