Record heat weakens Colorado snowpack, elevates avalanche risk

Unseasonably warm temperatures continue to take a toll on Colorado's snowpack, raising concerns about dangerous avalanche conditions across the high country.

Thursday's forecast brings more of the same: above-average warmth and conditions favorable for wet avalanches. While avalanche danger is beginning to decrease in some areas, experts warn that large and destructive slides remain possible—especially in areas with deeper snow.

The biggest concern right now is wet avalanches. Loose wet slides, which can start small, have the potential to gouge all the way to the ground and even trigger more dangerous wet slab avalanches.

Weak—or even nonexistent—overnight freezes have left the snowpack soft and unstable early in the day, limiting the window for safe travel.

According to Brian Lazar, deputy director of the Colorado Avalanche Information Center, the prolonged stretch of heat is unlike anything he's seen in March.

"A week of record-breaking temperatures, approaching nine days without the snowpack freezing… is taking quite the toll on our snowpack," Lazar said. "We are below 40 percent of the statewide long-term median, sitting at 34 percent as of Thursday."

That steep decline is directly tied to the recent heatwave. Lazar says even the most optimistic outlook for the rest of the season shows little chance of recovery.

"Even if we set daily maximum snow water equivalent records every day for the rest of the season, we would barely get back to the long-term median—and the chances of that happening are slim to none," he explained.

The rapid melting is also increasing avalanche activity in unusual places.

"We're seeing loose wet avalanches even on north-facing terrain and up into the alpine," Lazar said. "That's not something we typically see until late April—but here we are in late March."

One of the clearest warning signs: rollerballs—small snowballs that form and roll downhill, often signaling unstable, wet snow conditions.

Looking ahead, temperatures are expected to ease slightly, though they will remain above normal heading into the weekend. Thursday night could bring the first overnight freeze in more than a week, which may help stabilize the snowpack—at least temporarily.

Until then, experts urge backcountry travelers to adjust their plans.

"We are moving out of record-breaking heat into unseasonably warm temperatures," Lazar said. "So it's back to the mantra: start and end your day early."