It’s been thankfully cool this week, a big relief after the record heat wave earlier in the month. It was so cool last night that the San Bernardino Mountains saw a nice little layer of frosting this morning.
It’s not snow, nor is it hail.
“It’s called graupel,” said Philip Gonsalves, a meteorologist with the National Weather Service.
Again, graupel (pronouncer: GRAH-pul).
Gonsalves said it was caused by unusually low temperatures and thunderstorms up in the mountains last night. “Some of the precipitation that fell out of the thunderstorm fell as grapple. There was also some small hail mixed in with it,” he said.
How we know it’s graupel vs. hail
Many people confuse the two — but not if you know about the crush test.
“The easiest way to distinguish between graupel and hail, because they look similar, is that graupel you can crush relatively easily,” Gonsalves said. “Hail, you really can’t crush easily.”
That’s due to different processes from which the two are formed.