One year later, experts look back on historic avalanche cycle
FRISCO — Kreston Rohrig stood gathered among his colleagues at the Colorado Avalanche Information Center last winter, trying to determine just how dangerous conditions in the Summit County backcountry had gotten over the past few days.
Storm after storm was pounding the area, dumping seemingly endless piles of snow onto the slopes, just to break away in giant slabs onto roadways and valleys below. And with devastating avalanches wreaking havoc in turn around the state — and a new, massive slide path having emerged overnight on Peak One in Frisco — there was seemingly only one real answer: the danger had become extreme.
Forecasters like Rohrig measure danger on a five-point scale, from low to extreme. But pushing the scale to the far right is exceptionally rare, and less than a week earlier even Rohrig likely would have dismissed the idea as laughable.
“At the end of February, the snowpack was strong and deep and looking really good,” Rohrig said. “The only thing that could have kicked off a big cycle was a massive trigger or a huge snowstorm. And that’s exactly what we got.”
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Still, there was hesitation even among the experts.
“On March 7, storms had continued, and we were already seeing catastrophic avalanches,” Rohrig recalled. “I still remember that morning specifically, and I will forever. … How often do people see us go to extreme? It’s not often. It’s kind of like a unicorn; it’s there, but you never use it.
“We were tiptoeing around the issue, and I remember our Deputy Director Brian (Lazar) said, ‘If not now, when?’ We went to extreme danger in four zones, and that proved to be the right call. It was just absolutely mayhem. And iconically, that’s when Silent Bob out there ripped out and destroyed a massive swath of forest.”
It was a year ago today that Frisco residents woke up to a new slide path between Peak One and Mount Victoria, which has since been named “Silent Bob” among locals due to its proximity to the J Chute — a nod to the iconic stoner duo Jay and Silent Bob from Kevin Smith’s “Clerks.” A year later, Rohrig is hoping to put into perspective just how historic the avalanche cycle was last March.
Rohrig, who serves as the Colorado Avalanche Information Center’s backcountry avalanche forecaster for the Vail and Summit County regions, gave a presentation on last year’s avalanche cycle at Highside Brewing in Frisco earlier this week.
Like with most avalanche cycles, the foundation was laid early on. Early season snow in October set a relatively weak base layer in the snowpack, typically a bad sign for avalanche conditions. But with good snow conditions over the coming months, the snowpack was considered strong and stable by the end of February.
But in early March, the state was hit with back-to-back-to-back “atmospheric river” events moving in from Southern California. The three major storms hit March 3, 4 and 6, dropping between 2 1/2 and 7 feet of snow in areas around the Western Slope.
“In Colorado, if we get a foot of snow that’s pretty exciting,” Rohrig said. “When we get 7 feet, that’s overwhelming. … With that snow, we started seeing a bunch of avalanches. This huge spike was just way more than the snowpack could handle. As far as the event, it was pretty amazing.”
While snowfall for the season failed to reach historic levels, the storm cycle in March certainly did. According to Rohrig, citing SNOTEL snowfall data, Copper Mountain recorded its largest 10-day and seven-day storms in at least the past 40 years.
And while the cycle wasn’t particularly long — avalanche danger was back to moderate by March 18 and back to low by March 26 — it definitely took a toll.
In total, two people were killed in avalanches, two others were critically injured, 23 were caught in slides and four others were hospitalized. Additionally, power lines were damaged in five counties, 10 structures were damaged and countless roads were closed.
“All these numbers could have been a lot worse,” Rohrig said.
According to Rohrig, there were more than 1,000 recorded avalanches in just a two-week period and obviously many more that weren’t recorded. But perhaps what stands out even more is the destructive capacity of the slides. Rohrig said there were at least 87 avalanches recorded with a D4 rating or higher — the second-highest destructive rating. In the eight years leading up to the 2019 cycle, only 24 of that size were recorded in total.
“As far as a historic cycle, it really was that,” Rohrig said. “For much of our staff, we’d never seen anything like it. And most of us don’t think we will again in our careers.”
Rohrig said the Silent Bob slide itself also helps to shed some light on the historic nature of the cycle.
“The Peak One avalanche, which is near and dear to us here, felt like it was a completely new avalanche path. Amazingly enough, the (Breckenridge) Heritage Alliance found this photograph from 1899 showing that exact same path 120 years ago. That kind of speaks to the frequency of a cycle like this.”
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