Colorado’s snow is dust-free for the first time in a decade — the High Country News

Click on a thumbnail graphic to view a gallery of snowpack data from the Natural Resources Conservation Service.

From the High Country News (Krista Langlois):

This year, however, there appears to be a break in the cycle: Though a few storms have swept east from the plateau, they either haven’t had enough oomph to carry dust to the mountains, or they’re coming from places like eastern Utah where the dust was tamped down by late-winter snowfall. For the first time in a decade, March snowpack across Colorado is virtually dust free. Great news, right?

Not really, says Chris Landry, executive director of the Center for Snow and Avalanche Studies in Silverton, Colorado. Rather than cause for celebration, current dust- and snowpack conditions are about as close to worst-case scenario as you can get. For one thing, above-average temperatures statewide mean that in each of the 11 locations Landry sampled last week, the snow itself was “much warmer than usual. In some places,” he adds, “it was as warm as you can get and still be snow — warmed up all the way to zero degrees Celsius.”

Once snow hits that threshold, Landry says, it’s very unlikely to cool down again — meaning that even if skiers are lucky enough to get a few spring dumps, snowmelt in many places has passed a point of no return. Already, some stream gauges are showing runoff well above annual norms for this time of year.

Secondly, there’s just not much snow to begin with. In most Colorado watersheds, snowfall was subpar, and a long, dry, warm spell that lasted through February caused some slopes to become nearly bare — creating even more variation than usual between sunny, south-facing slopes and cool, shady ones. When Landry tramps around visiting data sites, he’s used to seeing a difference between conditions on the ground and the computer-generated SNOTEL maps, because SNOTEL sample sites tend to be flat and shady. This year, however, Landry worries the variations are higher than usual — so even maps showing snowpack at 67 percent of normal may be overstating what’s really out there. Less snow ultimately means faster rates of melting, and faster melting now means less water in streams and rivers this summer.

The last criteria for Landry’s “worst-case scenario” is a dry spring — which is exactly what we’ve had so far. Just as there have been few storms here in the mountains, there haven’t been many over the Colorado Plateau either, and that means conditions there are getting drier and dustier — primed for a big April dust storm. April is typically the biggest month of the year for dust events, and May isn’t far behind. So just because there’s virtually no dust out there right now doesn’t mean it’s not coming: “The Colorado Plateau is drying out,” Landry says, “And that almost ensures that if and when a major weather system moves through, dust will be available. We’ve had single dust events that in and of themselves would be more than adequate to really alter snowmelt.”

“Everybody is hoping for no dust,” he adds. “And that would be considered a good thing. But it’s also true that we’re a long way from being even reasonably hopeful that will be the case.”

From TheDenverChannel.com (Matt Makens):

The fire danger has increased this March. This is due to an unusually warm pattern with little moisture for most of Colorado.

The first week of March started with snow/rain and cool temperatures but the following three weeks were very warm and very dry.

The monthly average temperature was 4 to 8 degrees warmer than average for the state. Temperatures were near their averages for only a few days. Denver ends March more than 4-degrees warmer than its average…

This follows a dry start to the year. For three months in a row, temperatures remained warmer than average. This year, the only area of the state to have above average precipitation is a region of the Front Range along I-25 from Denver to New Mexico.

This dry and warm start to the year has raised concerns of the fire danger for the coming months.

Meteorologist Tim Matthewson of the Bureau of Land Management tells 7NEWS that the next 30 to 60 days will be critical for the fire season. To continue with below average precipitation could mean a bad fire season. He added, this is reminiscent of 2012, although not quite there yet.

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