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In CUriosity, experts across the �鶹��Ѱ�����Boulder campus answer questions about humans, our planet and the universe beyond.

Jennifer Kay, professor of atmospheric and oceanic sciences and fellow at the (CIRES) at �鶹��Ѱ�����Boulder, talks about why this winter has been so dry.

Jennifer Kay has a message for the skies above Colorado: “Let it snow.”

Kay is an atmospheric scientist who, in her free time, likes to go cross-country skiing in the Rocky Mountains.

But this year, the season’s typical white-out blizzards haven’t arrived.

Denver didn’t get its first snow—a wimpy dusting of just 0.2 inches—until Nov. 29, the second latest first snow on record. Temperatures around the Front Range have also been downright balmy, drawing close to or even setting record highs.

Could the late start to the winter be a bad omen for Colorado’s ski industry and its future water supplies?

Kay weighs in on the question from �鶹��Ѱ�����Boulder’s East Campus with a view of the Flatiron Mountains behind her. They’re almost completely dry, with almost none of the sprinkling of white that usually marks them this time of year.

She says it’s not time to panic—yet.

“It's also really early in the season still, so people shouldn’t be too worried about what’s going to happen with the ski season or water,” says Kay, a fellow at the (CIRES) at �鶹��Ѱ�����Boulder. “There are still a lot of different ways this season could unfold.”

In 2021, for example, Denver didn’t see its first snow until Dec. 10 (the latest on record). But snowfall totals inched closer to normal in the months that followed.

Kays says it’s not possible to predict how much snow will come to Colorado in an individual winter season months ahead of time.��

A lot of that stems from a phenomenon known as the jet stream. That’s the name for a narrow band in the atmosphere above North America where winds reach tremendous speeds, sometimes over 250 miles per hour. When this band hovers above Colorado, it tends to bring big, rumbling storms to the state.

“When the jet stream brings storms to us, we get … a lot of wet, snowy days,” Kay said. “If the jet stream goes another direction, maybe to the north or south of us, we don’t get as many snowstorms.”

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But, she adds, any number of complex factors can make the jet stream wiggle from month to month—although meteorolgists can often predict what the jet stream will do several days in advance.

Recently, the jet stream has stuck mostly to the north of Colorado, crossing over states like Montana and the Dakotas.

This year’s less-than-snowy winter has Kay thinking about what the future may hold.

With warming, she says, many storms that might normally produce snow may instead bring rain. That could have a wide range of consequences for the state.

A thick blanket of snow on the ground, for example, can keep wildfires from starting and spreading. The Marshall Fire, which devastated parts of Boulder County in December 2021, erupted at a time when the ground was relatively dry, and winds were especially fierce.

Kay believes it’s important for Coloradans to prepare themselves for hotter and dryer weather.

She lives in Boulder and keeps a go-bag packed at all times, even during the winter months. It includes a change of clothes, important documents, chargers for electronic devices and contact information for her neighbors.��

“I have already adapted to the reality of more fires as we get hotter and drier in Colorado,” she says. “Understanding what's happening around you and having a plan for extreme events like the strong wind events we have along the Front Range is important.”