What is the difference between hail and graupel?
Hail is frozen precipitation that can occur during thunderstorms and tornadoes, while graupel is soft, small pellets that disintegrate when handled.
Heavy rain mixed with hail batters parts of Las Vegas
Residents in Las Vegas, Nevada, were hammered by heavy rain and small hail Thursday evening. The National Weather Service warns of more thunderstorms later in the evening for the area.
After a harsh winter, many Americans are ready for warmer weather. But as the country transitions from cooler temperatures to warmer air, the threat of severe weather increases.
WHAT CAUSES HAIL TO BE DIFFERENT SIZES?
With severe weather, many just think of thunderstorms or tornadoes. However, graupel and hail can also be present during severe storms.
So what is hail and graupel, and how are they different?
Hail accumulating in a Williamsport, Maryland backyard. (@MDchelleBelle/Twitter / FOX Weather)
Hail is frozen precipitation that can occur during thunderstorms and tornadoes. At times, this is the hallmark of a strong thunderstorm.
Hail forms when drafts of air carry water droplets up into clouds high in the atmosphere where the air is below freezing. The water droplets collide with other droplets right before they freeze into ice, creating hailstones.
The variety of hail sizes. (FOX Weather / FOX Weather)
According to the National Oceanic and Atmospheric Administration (NOAA), hail can grow in different shapes and sizes. Typically, less than 1 to 4.5 inches.
In some cases, large hail can cause damage to aircraft, cars and homes.
FOX Weather Explains: What is graupel?
They look like hail, but are soft to the touch. Here's how graupel forms.
While graupel is soft, small pellets formed when supercooled water droplets freeze onto snow crystals, a process called riming per NOAA.
SOFTER THAN HAIL; HARDER THAN SNOW: WHAT IS GRAUPEL?
Most of the time, graupel is fragile and disintegrates when handled. If the rimming process is so intense, the snow crystal can grow to a semi-large size, but will remain less than 0.2 inches.
This makes graupel a lot less destructive than hail.
In many cases, graupel needs temperatures to be 45 degrees or cooler at the surface in order to form.