KTLA

Graupel vs. hail: What is the difference between the two?

As temperatures drop and precipitation dots the region, KTLA viewers have been sharing their images of the white stuff hitting the ground.

While snow is likely and hail is possible, much of the precipitation people are seeing is graupel, a different type of precipitation altogether.


So what’s the difference between hail and graupel?

According to the National Weather Service, graupel is snow that melts and becomes supercooled as it falls through a warm surface and forms ice pellets. Graupel is softer than hail, which is pure ice formed in thunderstorms. 

The texture of Graupel is soft and wet and forms in a process called riming. The riming process happens when supercooled water droplets at a temperature below 32 degrees freeze onto a snow crystal, according to the National Oceanic and Atmospheric Administration. 

If riming is intense, the snow crystal can grow but will remain less than 0.2 inches. Graupel particles are “particularly fragile” and disintegrate when handled, the NOAA said. 

Hail, meanwhile, is made up of frozen raindrops of ice from thunderstorms. The texture is hard and solid, the NWS said. 

According to the NWS, hail forms in strong upward winds in thunderstorms and then fall into the ground before melting. Hail can grow to very large sizes through the collection of water that freezes onto the hailstone’s surface, the NOAA said. Hailstones are at least 0.2 in size. 

While hail can be dangerous and even deadly, graupel is mostly harmless, at least from a “falling from the sky” perspective. Both can create wet and slippery conditions and drivers should take extra precaution when any precipitation begins to fall from above.