Parts of Texas experienced some unique precipitation last week — not hail, snow, freezing rain, or sleet, but something called graupel.
On Thursday afternoon, graupel fell in Uptown Dallas, according to WFAA, but what is this seemingly rare form of weather?
Graupel consists of small, soft pellets that are created as supercooled water droplets freeze on a snow crystal through a process known as riming. Sometimes, this process allows the rimed snow crystal to expand substantially, yet it typically stays smaller than 0.2 inches.
Often referred to as snow pellets or soft hail, graupel particles are delicate and tend to break apart upon first touch. Such precipitation has been described as “puffs” by the National Weather Service, while others have likened it to the frozen treat Dippin’ Dots.
“It’s basically just a supercooled droplet of water, and when it comes in contact with the different snow grains in the atmosphere they all just stick together,” meteorologist Aaron Treadway told the Austin American-Statesman.
The term has been used in weather reports since the late 1800s. It is Germanic in origin, meaning “pearl barley.” While similar to hail, graupel takes on a different composition and is formed through a different process. Typically, it is seen during the winter months.
Graupel is just one of many rare terms employed when describing weather phenomena. While people often use catch-all terms like snow in reference to flurries, in reality, more nuance may be justified. In fact, the Inuit have dozens of words for snow, and Scotland has over 400.
If you missed the short-lived graupel storm last week, you may have to wait a while until it happens again. As it stands, the National Weather Service has no graupel forecast in Dallas over the following week.
