Yesterday’s precipitation was for me a delight to see and my use of the word “graupel” in yesterday’s blog post took some of you by surprise. If you went to your dictionary, you might not have found it. It’s not in the dictionary that is here on my computer either but it’s a word that is used by meteorologists whenever this cold weather occurrence presents itself.

Graupel has the look of styrofoam that has been broken into small pieces. The process that occurs to create graupel starts out high in the atmosphere as snowflakes are falling. They hit a layer of supercooled water droplets. Stay with me here, supercooled water is in the form of a liquid but is below 32°. As the water droplets hit the snowflake they stick to its surface.

Think of graupel as a snowflake covered in frost, or rime. Generally it is a 2 to 5 mm clump falling to the ground. A soft clump. Not hard like ice as hail or ice pellets would be. Cool stuff, graupel.