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Joel Gratz keeps up a running patter as he tabs through screen after screen of color-coded weather maps on his laptop.

“There’s another storm coming in … The trough is just meh. The jet stream is good. Temperatures are good … The euro still has a bunch of snow over Wolf Creek … I would still say 3 to 6 inches is the right forecast.”

Gratz, co-founder and CEO of OpenSnow, is running through the routine he follows early every morning during ski season to create his Colorado Daily Snow report. Thousands of skiers, boarders and backcountry adventurers are waiting on it, eager for guidance on where to get the best snow and have the most fun. 

Ask any ski patroller, instructor or expert skier about snow forecasts and most of them will mention Joel Gratz and OpenSnow, a website and app that contains a full suite of snow reports, forecasts, time-lapse snow cams, radar, daily snow discussions and more for ski resorts worldwide.

Gratz traces the origins of OpenSnow to a day in November 2005, when he passed on a trip to Steamboat where forecasters were predicting a few inches of snow. A couple of days later a friend called to tell him she had been skiing waist-deep powder, possibly the deepest, fluffiest snow in 10 years. He was shocked, heartbroken and furious.

“How … Is …this … possible? Why are we not solving for this?” he wondered.

A unique set of skills

Gratz was highly motivated and well positioned to solve the problem. He skied all through childhood at Shawnee Mountain in Pennsylvania’s Pocono Mountains and has been obsessed with weather since he was 4. He earned his bachelor’s degree in meteorology at Penn State University before heading West to earn master’s degrees in business administration and environmental studies at the University of Colorado. 

In December 2007, while working as a risk-modeling analyst at ICAT insurers, he emailed his first forecast to a few dozen family members and friends. The Daily Snow report grew from there.

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Forecasting snowfall in Colorado is a challenge. The state’s mountains are a 200-mile-wide jumble of peaks, valleys and ridges, which run every which way and create microclimates that can produce 3 feet of snow at Wolf Creek, 10 inches at Steamboat and a trace in Breckenridge. Generalists, like the National Weather Service and AccuWeather, aren’t delving into the minutiae of a Colorado snow forecast. They have their hands full providing forecasts for millions of people across the country, helping them decide what to wear that day and warning them to avoid potentially dangerous weather.

Joel and his friends were also looking for big storms — so they could head right into the teeth of them. They wanted snow forecasts that could tell them how much snow would fall at Aspen versus Vail, Crested Butte and Breckenridge, with additional commentary on the certainty of the forecasts and possible alternative scenarios they should keep in mind.

“We are snow-obsessed, weather-obsessed, outdoorsy people. And we are not just planning what we are wearing on Monday,” Gratz said. “We might take off work. We might take off school. We might spend hundreds of dollars driving somewhere, flying somewhere, staying somewhere, you know, for the chance of a really special couple of hours in the snow.”

“He’s like, ‘you got to be lying.’ And then he saw it firsthand and he was like, ‘Oh my God.’”

— Billy Rankin, longtime ski patroller and now a guide for Eleven Experience

Gratz skis more than 60 days a year and is happy to line up two hours before the lifts open if the conditions are right. Same is true for most of the seven full-time staff and 12 contract forecasters at OpenSnow.

For the past 15 years, Gratz has gotten up early, usually around 4:30 a.m., every day of the ski season — Saturdays, Sundays and holidays included — to begin his research for the daily report. Working on his laptop out of his home or wherever he happens to be that morning — Japan, Vail and Florida during research for this article — he consults global weather models, data- and math-intensive programs that run on the world’s most advanced supercomputers, provided mostly free of charge by governments around the world.

“Does anyone think it’s going to snow today?” Levi Gratz’s ski instructor asks while on the gondola with Levi’s dad, Joel, during a ski lesson at Vail. Joel joined his son’s ski lesson for a few laps with other parents on a Sunday morning. (Hugh Carey, The Colorado Sun)

Instead of going right to the models’ snow forecasts, however, he pores over all the individual elements that can contribute to snowfall: low- and high-pressure systems, storm tracks, moisture content of the air, wind direction, the counterclockwise spin of a storm, and more. He turns those weather maps into a mental picture of the atmosphere and roughs out a general snow forecast for regions and resorts around the state.

“I do that because if all I do is look at the precipitation forecast, it’s kind of like getting the answer without working through the steps on your own,” Gratz said. “It lets me call BS on the modeling.”

It lets me call BS on the modeling.

— Joel Gratz, co-founder and CEO of OpenSnow

Only after he has developed his idea of snowfall to come does he look at the computer models’ snow forecasts. Sometimes his mental picture agrees with the models’ forecasts, and sometimes not. If not, he digs in further, reexamines his assumptions, relies on his extensive experience with Colorado snow, and finds a forecast that fits.

“Joel doesn’t just plug the numbers in and go with it. He puts the human factor in with the models and in with the physics and all the science behind the models,” said Billy Rankin, longtime ski patroller and now a guide for Eleven Experience adventure travel company. “He’s just really intuitive. He’s really good.”

Rankin met Gratz almost 15 years ago. Rankin had been sending Gratz snow reports from Irwin, where he led guided ski adventures. Although only about 10 miles northwest of Crested Butte it can get almost twice as much snow.

“He’s like, ‘you got to be lying.’ And then he saw it firsthand and he was like, ‘Oh my God.’ He loves stuff like that,” Rankin said. Soon after, Gratz added Irwin to his forecast sites.

Science + slang = sending it 

In a conversational tone peppered with ski-dude terms such as powder, fluff, free refills and spinning lifts, Gratz provides his latest take on the outlook for fresh snow for the next 10 days to two weeks. As part of the nuance necessary to make big decisions about skiing — be it spur-of-the-moment powder chasing or a more pedestrian decision about the best day to ski your home resort — he outlines the uncertainties and provides confidence levels for different forecasts. 

He owns up to surprises or mistakes. His enthusiastic commentary on ski conditions and highlight on fun to be had makes readers feel as if they are getting special info from a trusted friend. That friendly, honest tone has helped him gain fans not only among the ski-obsessed, but also more casual skiers.

Josh Abram, a financial analyst who lives in Lafayette, skis only weekends, mostly at Eldora. He started reading the Daily Snow when it was a simple blog and has stuck with it as it has grown to a full-fledged app and started charging for subscriptions. 

“He’s loaded up with meteorologists. They are actually making pinpoint snow forecasts for those resorts,” Abram said. “I read it daily even though I’m not able to ski nearly as much as I want to. But I still check that thing all the time just to see what’s going on.” 

Abram has several ski resorts in his list of “Favorites” on the app, other Colorado resorts he can use with his Ikon Pass including some fantasy destinations like Steamboat. Some have described the one-page snow reports and snow cams from snowy legends like Alta Ski Area in Utah and Grand Targhee Resort in Wyoming as “snow porn.”  

Joel Gratz, founder of Open Snow, at right, chats with an another skier on the slopes of Vail. (Hugh Carey, The Colorado Sun)

A few early successes predicting heavy snowfalls at specific resorts brought him an almost folk-hero status among the cognoscenti of the Colorado skiing community.

Gratz quit his job at ICAT in 2010 to work full-time with meteorologist and programmer Andrew Murry to launch OpenSnow’s predecessor, They launched OpenSnow a year later. Soon after, Gratz recruited snow-forecasting brothers-in-arms Bryan Allegretto in Lake Tahoe and Evan Thayer in Utah to broaden the scope of OpenSnow forecasts. In 2013, Sam Collentine, a young meteorology student and avid skier willing to do anything, came on as the company’s first employee. He is now its COO. 

They kept operations lean, never took outside money and ploughed any extra revenue into development and expansion of the site.

Many hands make first tracks

OpenSnow has become a full-fledged company, called Cloudnine Weather, with products for summer and winter adventuring. The firm’s unique culture has staff working from anywhere. Many are based near Western resorts, the company’s original focus, but they also live and work in the Midwest, East, Canada and even Europe. They are constantly on the move — especially “Powder Chaser Steve” — in search of great snow and skiing. A powder day is a perfectly acceptable reason to reschedule or cancel a meeting.

“So, this is just a group of passionate forecasters and developers that love weather, love skiing,” forecaster Allegretto said. “We bust our asses because we love the business and love the company and there’s nothing corporate about us at all.”

About 10 years ago, OpenSnow began charging $19.99 for an annual subscription that gave access to a few of the more advanced features of the app and website. But as one of Gratz’s Boulder business mentors said, it was really a “freemium” service that gave away most of the prime content. In December 2021, they went all-in for the subscription approach, locking down the site, or most of it, behind the subscription paywall, hoping to develop a more reliable source of revenue that did not rely so much on fickle advertisers.

Joel Gratz, founder of Open Snow, skis the soft snow conditions on a Sunday morning at Vail ski area. Gratz grew up skiing in Pennsylvania before moving to Boulder to earn a master’s in business administration and environmental studies. (Hugh Carey, The Colorado Sun)


“A lot of people were using us for free. And we thought if we just asked them very directly to subscribe … like, ‘Hey, now’s the time,’” Gratz said.

It was a big step. Removing ads from the website and app cut into revenue. They risked losing thousands of visitors who might defect to the many free websites providing detailed weather information. Once the strict paywall went up, there were howls of protest, accusations of money-grubbing and many who declined the invitation to subscribe. But overall, it worked.

“Subscribers went off the charts because there were all these people that had used us for years that really appreciated what we did,” Gratz said. “That was really important to me to earn the subscriptions.”

Revenue increased and became more reliable. Gratz says renewals are excellent, “about as good as it gets.” This past year, they raised the annual subscription price another $10 to $29.99 after market research suggested they were pricing it too low. With pride, he mentions paying competitive salaries for meteorologists and software engineers and still being able to distribute “really good bonuses” this past year.

They are planning to add two or three developers to help work on Gratz’s list of “300 ideas” to improve the site. The meteorologists and software engineers have worked together to build their fledgling weather model and recently added a “forecast anywhere” feature that provides a custom forecast anywhere you drop a pin on their maps. Gratz expects to combine OpenSummit, a sister app for summer activities, and OpenSnow into one app in the next year.  

Success has brought a few offers to buy the company, which Gratz says he seriously considered in consultation with his OpenSnow team and his wife, Lauren, who is also a devoted skier. Maybe someday, but not now.

“We love what we do and the people that we’re working for, our subscribers,” Gratz said. “We are so lucky. And we’re now making enough money that it’s like everybody’s making a great living. Why would I change that?”

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William Allstetter

After more than three decades’ experience in journalism, science writing, editing, book publishing, corporate communications and video production, William is happy to be freelancing once again about science, skiing or any good story. Twitter: