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The Science of Snowflakes

Our Leaf Drop Cam in Massachusetts has become a Snow Cam with the onset of winter.

A few facts about snow crystals [AKA snowflakes]: They are formed from water vapor that condenses directly into ice inside of clouds…

Temperature and humidity are the two main factors that influence how the crystalline structure forms. At low humidity you get simple plates and simple hexagonal blocks. At higher humidity, more branched structures. We see that thin plates and stars grow around 28 F, while columns and slender needles appear near 23 F. A combination of plates and columns are made around -22 F.

Keep reading at PBS.

Catch a falling snowflake on the live cam.

(Photo from PBS)