ST GEORGE — Here in the desert, snow is somewhat rare. When flakes begin to fall from the sky, it is rarely in large amounts and doesn’t stay on the ground long. This makes graupel snow — a particularly unique form of frozen precipitation — an uncommon phenomenon in the St. George region.
When Jerry Whitworth drove up to the Oak Grove campground in late November, a storm was coming over the crest of the Pine Valley mountains. Soon, what appeared to be snow began falling from the lowering sky and Whitworth took in the quiet serenity of the scene.
But then he noticed something odd about the snowflakes: They weren’t really snowflakes at all, but tiny ice pellets that were cone- and saucer-shaped. Yet these pellets didn’t look or behave like hail, instead they fell from the sky like snow, gently drifting to Earth. Whitworth got out of his Volkswagen van and took a closer look, snapping photographs and shooting video of the odd precipitation.
Whitworth was soon joined by his friend John Teas, who is a photographer for St. George News.
What Whitworth and Teas were seeing was graupel, a curious and unusual phenomenon caused by super-cooled droplets of water coating a snowflake and then falling to Earth. Lighter and fluffier than hail, graupel looks and feels like frozen Styrofoam. According to the National Avalanche Center, graupel can cause a weak layer in snowpack, greatly increasing avalanche danger.
While he has seen grauple numerous times, Teas said, the cone-shaped variety they saw was unlike any he had ever seen before.
“The cone-shaped graupel Jerry and I ran into up at Oak Grove Campground — that is the strangest thing I have ever seen, weather-wise,” Teas said.
“The cone-shaped graupel is extremely rare,” Teas said. “It takes strong winds … where it can come through a canyon and form whirlwinds and take the graupel from little Styrofoam-looking pellets to a cone. I have never seen cone-shaped graupel.”
It looked like a cone, a “little spaceship, or a flying saucer,” Whitworth said. He poked it with his finger and was surprised when it melted quickly, not at all like hail or sleet.
“It was soft like snow,” Whitworth said.
He took out his camera to prove to others what he was seeing.
A short time after the flurry started, it stopped, but soon began again, this time dropping an increasing number of the pellets.
“It just dropped,” he said, “like heavy snow would drop, soft and slow, except it wasn’t snowflakes, it was pellets. I just thought it was super weird and strange.”
Graupel is basically a combination of snowflakes and water droplets, said Monica Traphagan, meteorologist for the National Weather Service in Salt Lake City. It is a type of riming — the weather phenomenon that occurs when super-cool water droplets freeze against objects, commonly seen in the mountains.
“It doesn’t happen a lot in St. George because you guys don’t get a lot of frozen precipitation,” Traphangan said. “Here in Salt Lake, we see it several times a year.”
Graupel fell again on Christmas Day, Teas said. This time, falling on his house in St. George.
“When we were out the other day,” Teas said, “and that storm came through, it came on us again.”
“It was Christmas graupel,” he said.
Rarely do people know what graupel is, Teas said, despite there being several instances of it falling each year.
“As soon as I say we had a graupel storm, everybody goes ‘what?'” Teas said.
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