CDOT: Avalanche mitigation along I-70 completed following multiple storms over holiday weekend

Colorado Department of Transportation

Avalanche debris covering US 6/ Loveland Pass from the Seven Sisters slide paths.
CDOT photo of avalanche debris covering US 6/ Loveland Pass from the Seven Sisters slide paths that was remotely triggered using Gazex Avalanche Control System on Tuesday, Feb 17, by CDOT teams.

Winter operations teams have safely triggered and cleared avalanche slide paths along I-70 through the mountain corridor following successive storms from last Thursday night through Tuesday morning. Measurements taken this morning on the summit of Vail Pass counted 28 inches of snow and 2.2 inches of snow water equivalent.

Those storms brought heavy accumulations of snow and high winds, which made for extreme conditions over long stretches of the Presidents Day weekend. With high volumes of car and truck travel, CDOT crews and law enforcement cleared vehicle spinouts, in addition to clearing roads of snow throughout the extended holiday weekend. Some periods of time saw short and intense bursts of snow that impeded visibility.

“Mother Nature did not take off for the holiday weekend. To the contrary, we saw some of the most intense snow totals of the season in the high country and multiple consecutive storms. Mountain Corridor ski resorts reported more than a foot and a half of fresh snow in 48 hours and more than four feet of snow in the past seven days. CDOT crews have been working around the clock to clear roads and mitigate avalanche risk, including a number of mitigation missions this morning. We remind drivers that conditions remain challenging. Please drive carefully through the tail end of this weather system, and watch out for snow plows and law enforcement who are working hard to keep the roads safe,” said CDOT Executive Director Shoshana Lew.

Every winter, CDOT and its sister agency, the Colorado Avalanche Information Center (CAIC), regularly monitor and control 278 of 522 known avalanche paths located above Colorado highways. These efforts help prevent avalanches from impacting motorists on the highways below. When there is a high risk of avalanche danger, CDOT will close the highway at the location of the avalanche path to conduct avalanche control. After the highway is closed, CDOT crews bring down the unstable snow from the mountain side and clear all snow and debris from the roadway before reopening the highway to traffic.

Four avalanche slide paths between the Eisenhower-Johnson Memorial Tunnel and the town of Silverthorne released debris onto the lanes of I-70 early this morning as crews performed mitigation missions. I-70 was briefly closed while these slides were triggered and crews cleared the road.

“The mitigation methods used in the early morning hours, before daylight, allowed our crews to work when traffic volumes are low,” said CDOT Director of Maintenance and Operations Shawn Smith. “This work is critical for keeping our roads safe, especially after the volume of snow we have seen over the past few days. We appreciate drivers’ patience as the team performs this important work of triggering avalanches and subsequent cleanup, which significantly reduces the risk of natural slides.”

“CAIC forecasters have been busy reading the snowpack for both backcountry users and Colorado highways,” said Ethan Greene, Director of the CAIC. “With avalanche danger rated as HIGH in the Northern Mountains, we’ve been diligent about communicating this danger to the public and working closely with CDOT maintenance crews.”

During a later morning mission, crews performed essential winter maintenance operations on Vail Pass, between Exit 180/ East Vail and Exit 195/ Copper Mountain, around 9 a.m. with five snowslides mitigation and one reaching the interstate lanes, as much as four feet deep and 175 feet in length.

Visit COtrip.org for the latest information on road closures and conditions.

Visit the Colorado Avalanche Information Center’s website, colorado.gov/avalanche, for avalanche forecasts.

A map of snowfall in Colorado from February 14-17.
CDOT map indicating accumulated snowfall seen throughout the state from Friday, Feb. 14, through Monday, Feb. 17.

CDOT: Avalanche mitigation along I-70 completed following multiple storms over holiday weekend

CAIC and NWS: Heavy snow and strong winds can cause deadly avalanches

Colorado Avalanche Information Center and National Weather Service

SPECIAL AVALANCHE ADVISORY

BULLETIN – IMMEDIATE BROADCAST REQUESTED
COLORADO AVALANCHE INFORMATION CENTER
RELAYED BY NATIONAL WEATHER SERVICE DENVER/BOULDER CO
436 PM MST SAT FEB 15 2025

Map of special avalanche advisory area

THE FOLLOWING MESSAGE IS TRANSMITTED AT THE REQUEST OF THE COLORADO AVALANCHE INFORMATION CENTER.

…A SPECIAL AVALANCHE ADVISORY IN EFFECT FROM 4:30 PM SATURDAY UNTIL 5 PM MONDAY…

*WHAT…Heavy snow and strong winds dramatically changed avalanche conditions. You can easily trigger large, deadly avalanches throughout Presidents Day weekend.

*WHERE…Flat Top Mountains…Medicine Bow Mountains…Never Summer Mountains…Front Range…Williams Fork Mountains…Never Summer Mountains…Gore and Elk Mountains…Ten Mile Range…Ruby Range…West Elk Mountains…Sawatch Range…San Juan Mountains…San Miguel Mountains…Rico Mountains…Grand Mesa

*WHEN… The Special Avalanche Advisory goes from Saturday at 4:30 PM till Monday at 5 PM.

*IMPACTS… Easily trigger dangerous avalanches large enough to injure or kill you.

*PRECAUTION/PREPAREDNESS ACTIONS… Travel in backcountry avalanche terrain requires cautious route finding to stay safe. Avoid travel on and under slopes with a slope angle steeper than about 30 degrees. You can find more detailed information at colorado.gov/avalanche.

CAIC and NWS: Heavy snow and strong winds can cause deadly avalanches

CAIC: Avalanche warnings in effect for busy and notoriously dangerous holiday weekend

Colorado Avalanche Information Center

A person stands on a slab of snow on a potential avalanche slope.
Avalanche conditions are changing fast. This slide caught CAIC forecasters off guard earlier this week — before the huge storm that’s about to hit. While doing fieldwork on Vail Pass, they unintentionally triggered this large (D2) Persistent Slab avalanche on a 27-degree, wind-drifted, north-facing slope. The incoming storm will increase the avalanche danger to HIGH (4 of 5) in many places across the state.

The Colorado Avalanche Information Center (CAIC) is warning backcountry travelers that the avalanche danger will rise to HIGH (4 of 5) over the Valentine’s Day and Presidents Day weekend, one of the busiest—and, historically, most dangerous—times of the season.

“We want people to enjoy a holiday weekend in the mountains, but they need to make sure their plan matches the avalanche danger, which will be higher than it has been in a month and a half,” said CAIC Director Ethan Greene.

A powerful storm is set to arrive Thursday night, bringing heavy snowfall and strong winds to the mountains through Saturday.

“Starting Friday, the avalanche danger will be HIGH in a lot of our mountains west of the Continental Divide,” said Greene. “We’re particularly concerned about avalanche accidents this weekend because portions of our snowpack are quite weak. We’ll see heavy snowfall after a fairly dry period, and lots of people will be heading into the backcountry to enjoy the holiday weekend.”

February is the deadliest month for avalanches in Colorado, and Valentine’s Day through Presidents Day weekend is the most dangerous period of the season. Over the past 10 years, eight people have died in avalanches between February 14-16.

“We expect natural avalanches this weekend, and people venturing into the backcountry will be able to trigger slides big enough to bury, injure, or kill them,” Greene warned. “And once the skies clear on Sunday, the chances of an accident will increase due to the nice weather, new snow, and dangerous avalanche conditions.”

CAIC assigns avalanche danger ratings using the North American Public Avalanche Danger Scale, ranging from LOW (Level 1) to EXTREME (Level 5). When conditions become particularly hazardous, CAIC issues Avalanche Watches and Warnings to alert the public. Additionally, Special Avalanche Advisories are released when a significant safety risk coincides with a high-traffic period, such as a major storm during a holiday weekend.

Backcountry travelers should take the following precautions:

  • Check the avalanche forecast before heading out: colorado.gov/avalanche
  • Avoid avalanche-prone terrain during periods of heightened danger.
  • Always carry proper avalanche safety gear, including a transceiver, probe, and shovel — and know how to use them.
Avalanche fatalities in Colorado, 2005-2024, chart showing that February is the most dangerous month of the year.
February is historically the deadliest month for avalanches in Colorado, with the highest concentration of fatalities occurring between February 13-16. Over the past 20 years, more than one-third of all February avalanche deaths have happened during this four-day period — nearly double the expected number if fatalities were evenly distributed throughout the month.

CAIC: Avalanche warnings in effect for busy and notoriously dangerous holiday weekend

Snow Pool: sign up for backcountry avalanche conditions

Colorado Avalanche Information Center (CAIC)

The Colorado Avalanche Information Center (CAIC) and the Avalanche Research Program of Simon Fraser University in Canada are building SNOW POOL, a community of backcountry users interested in providing feedback about their backcountry experiences and willing to review, share feedback, and provide suggestions about how to make avalanche safety information work better for everybody.

Who should sign up?

You do not have to live in Colorado or have any avalanche knowledge to participate. We are interested in the perspectives of all types of users with all levels of experience. We are especially interested in hearing from individuals who are just starting their backcountry adventures or only occasionally go into the backcountry.

What can participants expect?

Individuals who sign up will receive regular emails from CAIC and SFU to participate in short online user surveys and the opportunity to provide feedback on CAIC products and priorities. This is an opportunity to be part of a community that contributes to the development of improved avalanche risk communication, learn about CAIC research projects, and be eligible for incentive programs or entered into raffles hosted by some of our partners.

More information and sign up link are available online.

Snow Pool: sign up for backcountry avalanche conditions