Editor’s note: This article was originally published on April 21, 2017. It has been updated for accuracy March 2018.

Just because the spring sun is shining doesn’t mean it’s open season in the Colorado backcountry.

Need proof? Look to the past: In 2013, a massive avalanche let loose along the Sheep Creek drainage near Loveland Pass, trapping and killing five snowboarders under several hundred tons of snow up to 14 feet deep. The slide happened on April 20 — the Friday before closing day at Breckenridge — at the tail end of a hit-or-miss season, when wildly unpredictable snowfall in December and January led to persistent weak layers under wet, heavy spring snowfall.

“It’s easy to let your guard down in the spring because things are generally more predictable,” said Brian Lazar, deputy director for the Colorado Avalanche Information Center. “But you have to remember we’ve had avalanche fatalities every month of the year in Colorado.”

In 2016-17 season, two backcountry travelers were buried or killed in a Colorado avalanche, triggered northwest of Summit County in the Flat Tops Wilderness by two ski bikers on Feb. 14. One died, the other survived. That’s about five fewer deaths than the state’s 10-year average of six deaths per season, but as Lazar said, Colorado snow can be deadly all year long, and it’s the same story across the nation. From 2007 to April 2017, a total of 24 travelers have died in April avalanches between Wyoming, Alaska, Washington, Oregon and Colorado, according to CAIC data.

Know your forecast

April is the true start of spring alpine-touring season. Backcountry skier Fritz Sperry, author of the “MakingTurns” guidebook series, has been making the rounds to 14ers and 13ers in and around Summit. He skied San Luis Peak (14,014 feet) in the San Juan Range — a 17-mile tour with 7,000 vertical feet of climbing — and The Caldera, the wide-open south bowl on Buffalo Mountain.

“I’ve been looking at that line for 25 years now, and it was nice to go back and get it done,” Sperry said of The Caldera.

Before leaving on any backcountry tour, Sperry goes through the same checklist. It begins with checking daily the avalanche forecast from the CAIC (available through a free mobile app), which details everything a skier needs for a tour: recent avalanche activity, problem aspects, wind-loading events and more, including ground-level observations from fellow travelers.

But come springtime, the CAIC forecast isn’t updated daily like it is in the thick of winter, and so backcountry travelers need to fine-tune their forecasting skills.

“The first thing people need to understand when they go in the backcountry is that this is not a ski area,” said Karl Birkeland, director of the U.S. Forest Service National Avalanche Information Center. “They are fully responsible for themselves when they are out there: responsible for assessing the avalanche conditions, responsible for rescuing partners if things go bad and responsible for assessing the specific terrain they want for that day.”

For Sperry, if a pre-tour assessment just doesn’t pass the test of experience and knowledge, he’ll turn around — even if he spent several hours getting into avalanche-prone terrain. It happened twice this season on Kit Carson Peak (14,170 feet) in the Sangre de Cristo Range: He encountered a nasty wind slab after traveling for seven miles and was forced to leave.

“That can be frustrating, but pushing peaks when the conditions aren’t right isn’t healthy,” Sperry said. “It will be so much better when you come back and the conditions are where you want them to be, but (turning around is) not a failure. Seeing the signs and listening to them — heeding the warnings — is a success in itself.”

Know your route

For experts like Birkeland and Lazar, one major misconception about avalanches is where they tend to let loose. Yes, many avalanches are triggered by downhill turns in wide-open bowls, but the danger is present from the moment you set ski to snow.

“We also give travel advice: what slopes to avoid, where you’ll be likely to run into problems, all of that,” Lazar said, referring to weekly CAIC updates in the latter part of the ski season. “It’s a way to key in on what’s happening out there and ways to keep yourself safe.”

In Summit County, where higher altitudes lead to colder temperatures in April and even May, balmy spring days can wreak havoc on exposed terrain near rocks, cliffs and other outcroppings. Lazar points to classic lines on the westerly aspect of the Tenmile Range — Gasoline Alley, the SKY chutes — where prolonged exposure to sun can lead to rapid warming and “wet” avalanche activity. Common signs of danger are pinwheeling balls of snow and soft, slushy surface snow that sinks more than six inches under a boot or ski.

“Now is when it’s time to exit avalanche terrain, and either move to colder, more protected slopes, or avoid the terrain altogether,” Lazar said of seeing wet avalanche signs. “Plan your routes and travel early in the morning.”

Next on Sperry’s checklist are real-time conditions: Is the snow perfect corn, or is it rock-hard ice? Is the sun high enough to heat northern aspects, or is it too low? Did it snow the night before? If so, how much, and is it binding well to the old stuff?

While Lazar says reports are showing a typical spring snowpack, Sperry’s experience in the field has been slightly different.

“A lot of the snow I’ve been seeing isn’t quite a spring pack yet,” Sperry said. “On the north (aspects) things are more wintery still. It’s getting there — it’s getting firm and warming up — but the angle of the sun isn’t high enough yet. Later in spring the sun will hit northeast faces first, but right now that’s not happening yet.”

Know your ability

One of the final major mistakes the experts notice is a disconnect between perceived ability and actual ability. This doesn’t mean you suck — it just means you’re new to this whole backcountry thing.

“You could say there tends to be a mismatch between some people’s skill at their sport and their avalanche or backcountry skills,” said Birkeland, who noted that instant access to insane footage on social media has highlighted this concern. “They head out to terrain that matches their skill level, but that terrain is over their head for assessing the avalanche conditions … What people really need to do when they first go into the backcountry is dial things back a bit.”

Sperry suggests dialing things back a ton. It’s something even veterans like himself do: When the snow on San Luis Peak went from hard-pack to corn to slush during the descent, he and his crew adjusted their plan of attack.

“We skied conservatively until we got to the corn, then we let it loose,” said Sperry, who added there are “no heroes and no egos” in the backcountry. “We adapted to the conditions. It was your San Juan epic sort of thing — everything on one trip.”

The final tip to remember is the difference between goals and objectives, Sperry and Birkeland said. Your goals can be bottomless — skin that route, summit that peak, ski that line — but your objective is always the same: to get home alive.

“One thing everyone needs to realize is that the mountains will be there tomorrow and next week and next year,” Birkeland said. “They aren’t going anywhere. There are days when everything is nearly safe and there are days when the mountains will kill you. You need to pick the right days to be there.”