Graupel: You're Full of Sleet...What The Hail Is That?

Graupel - little ice pellets

With the current band of rain moving into a chilled airmass over Southern Kentucky this morning, many of you are reporting “sleet” or “hail” or just plain ol’ “ice pellets”.

Technically, it’s graupel.

Graupel – (also called soft hail or snow pellets; METAR code: GS) refers to precipitation that forms when supercooled droplets of water are collected and freeze on a falling snowflake, forming a 2–5 mm ball of rime. The term graupel is the German word for this meteorological phenomenon.  Graupel is sometimes referred to as small hail, although the World Meteorological Organization defines small hail as snow pellets encapsulated by ice, a precipitation halfway between graupel and hail.

Not to worry…we will keep referring to this as “ice pellets” but you can see why the technical definition does not equal that of sleet or hail.  It is, however, more of a winter-leaning phenomenon but we’ll leave it at that.

Ground and road surface temperatures are still too warm for these tiny ice pellets to cause any travel issues this morning but it is a sure sign that we are not far away from what could be an eventful Winter season ahead.

To that end, parts of the Mid Atlantic states and New England are forecast to see their first Nor’easter this weekend with 3-6 inches of snow predicted as close as the hills of West Virginia!

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