Hey fellow skiers & snowboarders! I am excited to ski! How about you?

I am anxious for it to snow, for ski resorts to open, and for my favorite ski runs to open. You and I both know the whole pre-season anticipation and waiting…

OpenSnow.com, my weather apps, and the local news tell us when and how much it is going to snow at the entire ski resort. Ski resorts post their opening date.

But until now, there has not been any resource to forecast when anyone’s favorite SKI / SNOWBOARD RUNS & TRAILS are going to open for the season – only for the entire RESORTS. Just like you, I wait anxiously during pre-season, yearning to make that epic line down Imperial Bowl.

So when are YOUR favorite ski runs going to open?

In this pilot post, I will explain that I just *might* have some of these answers for you…

Previous Observations:

While no one can predict very-far in-advance how much snow that any ski resort, on any given date, is going to receive – here are a few certainities:

  1. Sooner or later, it will snow.
  2. Each ski resort’s Snow Management Operations team will open ski runs, generally in the same order each year, and most-often based on the current snowpack.

Arapahoe Basin, Loveland and Wolf Creek have had a friendly competition for decades about each one trying to be the first snow resort to open for the season.

Typically, Arapahoe Basin and Loveland were the main contenders: …however when 44-inches of fresh snow dumped on Wolf Creek on / just before October 8, 2011, then Wolf Creek became clearly a member of the Early-Opening Club.

* New for the 2019-2020 Ski Season *

For the 2019-2020 snow season, Vail Resorts announced additional snowmaking capabilities at Keystone, Beaver Creek and Vail – with the intent of especially adding Keystone to the early-opening club to next-door neighbors Arapahoe Basin and Loveland.

Public Debut of Ski Run Forecast: a fledgling venture to eventually provide a broadcast service forecasting when ski runs/trails are going to open for the current season, based on current versus historical snowpack thresholds needed to open each ski run.

This is a list of all of the ski runs at the following 21 ski resorts that I tracked during the 2018-2019 ski season:

During the past ski season, using a network of Excel Spreadsheets, I tracked the opening dates and current snowpack threshold of every INTERMEDIATE BLUE, SINGLE BLACK DIAMOND, DOUBLE BACK DIAMOND AND EXPERTS-ONLY ski run on their initial opening date of the season, at the above ski resorts.

Certain patterns emerged that I always knew were there, for example:

Arapahoe Basin first opens High Noon, then Ramrod, then the ski patrol starts opening the Upper and Lower Lenawee Zones that are: Cabin Glades, Dragon, Falcon, Lenawee Parks, West Gully, Dercum’s Gulch, Humbug, Leawee Face, Powerline and Norway Face.

Then the ski patrol moves to open runs like Exhibition, Cornice Run, West Wall, Lynx Lane, Easy Gully, Challenger, Radical, Scudder, 13 Cornices and International. After all of these runs are open, you need another 7-inches of snowpack before you can start seeing Pallavicini & friends opening.

On December 16, 2018, C.E.O. Al Henceroth stated, ‘The East Wall typically opens when the mid-mountain base is somewhere around 50 inches. That can vary a bit depending on snow, wind and avalanche conditions’.

Al was not far-off: Lower East Wall Below the Traverse opened with a 53-inch snowpack on January 22, 2019, and was the 137th ski run at Arapahoe Basin to open for the season. Upper East Wall was not far behind.

I know, because every day, I recorded every new ski run that opened, all season long, by going to 21 different ski resort websites twice a day, and recording the same on spreadsheets.

Yes. This effort was just as difficult and tedious as you think.

To ascertain potential interest in the ski community, I posted a conversation starter:

Thirty people commented. Their favorite ski runs are:

  • Oz and White Cap Glades-Sunday River Ski Resort
  • Rime at Killington and T2 at Sunday River Ski Resort
  • HoneyComb Canyon- Solitude
  • Granite Chief- Squaw Valley
  • Lone Peak- Big Sky
  • Mineral Basin- Snowbird
  • Mary Jane- Winter Park
  • Powerline Glades : Snowmass and Far West: Copper Mountain.
  • Heavenly
  • Chair 23-Mammoth
  • Brighton, Solitude, Snowbird, Alta and Deer Valley.
  • Montezuma Bowl-A-Basin
  • Top of Chair 9-Loveland
  • Imperial Express- Breckenridge
  • Thunder Wolf lift-Big Sky
  • Stump Alley-Mammoth
  • KT 22 & Granite Canyon-Squaw Valley
  • Coombs-Jackson Hole
  • Rock island-Snowmass
  • Lazy Gondola Laps–Ajax [Aspen Mountain]
  • Christmass Tree [Bowl]-Steamboat
  • Cooper Mtn drops [I think they meant “Copper Mountain”]
  • Revelstoke LL & Sunshine
  • The Canyon and Needles Eye areas-Killington
  • Cirque-Snowbird.
  • Panoramic-Winter Park
  • Tophers Trees-Winter Park
  • Westward Ho and Catherine’s-Alta
  • Stein’s Run-Deer Valley

Limitations to any Forecast:

Let’s suppose that, like social media poster Lucas, you were hankering to ski Arapahoe Basin’s Montezuma Bowl…and I told you that it took 35 inches of snowpack before ski patrol had opened Montezuma Bowl on Tuesday, December 7, 2018, and 39 inches of snowpack before ski patrol opened all of Montezuma Bowl on December 31, 2018.

Now there is an important difference between “snowfall” and “snowpack”.

In the early season, the snowfall to snowpack is a 2-1 ratio, which means that for every foot of new snow, six-inches of snowpack is the result. Things like skier compaction, sun and even wind all break down snowflakes and crush them into “pack”. By the end of the season, this ratio (in-part due to skier & boarder traffic, as well as rising temperatures resulting in melt) makes this ratio more like 3-1 or even 4-1 before Spring.

It might have snowed 400-inches during the season, but by Spring, your average snowpack is only about 100-inches.

So you look at Arapahoe Basin’s website on December 15th of your ski season, and you see that the ski area is reporting 30 inches of snow pack, just 5-inches shy of the threshold to open Montezuma Bowl.

Then you log on to OpenSnow.com and Joel Gratz is telling you that 6-inches of fresh snow will be falling on Arapahoe Basin on Friday, so you plan on heading to A-Basin Saturday morning to be first in line when ski patrol opens Montezuma Bowl.

And it does not open. Why?

First, six inches of fresh snow amounts to three inches of snowpack, in-which, if the ski patrol was that precise, then this only puts the total snowpack at 33 inches, not the 35 inches of snowpack necessary to open Montezuma Bowl.

Next, ski patrol needs some lead time for avalanche mitigation: blasting, measuring, assessment, review and finally authorization before dropping the rope. Depending on a number of circumstances, especially things like wind, which I have not recorded or tracked, this could take days or even more.

However, let’s suppose that there has been a few days dry spell, and based on this, ski patrol has not been doing much avy-mitigation work. On top of your 30-inch base comes a snowstorm dropping 16-inches, resulting in approximately another 8-inches of pack on top of the already existing 30-inch base. At 38-inches of soon-to-be snowpack, then likely this situation is only governed by the amount of lead-time that the Arapahoe Basin ski patrol needs to open up Montezuma Bowl. This might be a day, less than a day, or two days, or more.

But it is does set-up the situation to be imminent and on the event horizon: nearly all of the snow pieces are in place to meet the threshold to open up Montezuma Bowl at Arapahoe Basin. All we need now, is the formality and the official rope drop. We have passed the plateau: Mother Nature has done her job, now we are only waiting on the human management element.

Of course, the human element can be almost as unpredictable as the weather. Just for the sake of argument, I could post anticipating an opening of Montezuma Bowl to occur within the next week to this blog. And just to spite me, there is nothing stopping the ski patrol from reading this blog and deciding to open Montezuma Bowl a few weeks later instead. This type of analysis implies that the snow management team from every ski resort employs the same level of thresholds, every season consistently and that the snow delivered from Mother Nature is the primary threshold for opening up ski runs.

I observed the best early-season conditions at Copper Mountain during the 2017-2018 ski season, and Breckenridge was a winter wonderland for the 2018-2019 ski season. During many ski seasons, I have seen Breck open with a half-dozen ski runs on the second week in November opening day – however last season was different, and by the end of the day on Friday, November 9, 2018, Breck had over 30 ski runs open. Typically Peak 8’s Spruce is consistently the first black diamond run to open, often on opening day itself. Breck’s pattern has been first Peak 8 (or most of), then on to Peak 9, Peak 7, Peak 10, Peak 6 and last to open are Peak 6’s Hike-To Terrain.

However, there are exceptions: Peak 8’s South-Facing ski run Goodbye Girl is often never to open. Breck tends to open huge sections all at once and are less likely to piecemeal-in run-by-run. Last ski season, I was shocked to find the Imperial Chair running on November 22, 2019 – when in some past seasons, Imperial did not open until well into January.

This next ski season, I will be at it again, painstakingly flipping through ski resort website’s, “Open Terrain” sections, twice a day and recording it all on yet another set of Excel Spreadsheets.

However, this next season I will be VALIDATING and paying close attention to any differences between how much snowpack it took to open all of these ski runs between both ski seasons, and trying to discern consistencies, patterns and models to work from in the future. If it took 53-inches of snowpack at Arapahoe Basin for ski patrol to open Lower East Wall during the 2018-2019 ski season, and it takes the same (or close-to) 53-inches of snowpack to open East Wall during the 2019-2020 ski season, then I think we have a legitimate threshold to work from and potentially develop a service using this information.

Some of this information just might come in-handy, for me…and you.

For example, I just-happen to be at Big Sky in Montana when unbeknownst to me, that the ski patrol allowed limited drop-ins down Big Couloir on Friday, December 21, 2018 with a reported snowpack of 31-inches of snow at the base, 36-inches at mid-Mountain and 54-inches at the top. It was not until Big Sky consistently reported 44-inches of snowpack before Big Couloir was open and stayed open.

However, Big Sky’s website shown Big Couloir to be closed, when my ski buddy Vincent and I checked and left the parking lot – and left our beacon, probe and shovels in the car (required avy gear for skiing in-bounds Big Couloir)

Only to our dismay after riding the tram to ski Lone Peak, we discovered that the ski patrol really had opened Big Couloir, but just not reported the same to their website. They were closing Big Couloir in 30 minutes, and had we brought along our avy gear anyway, then we would have been able to ski a an epic run of a lifetime – but it would be impossible to ski down to the car, get our avy gear and make it back up in-time while Big Couloir was still open.

My point is this: my report is only as good as what the ski resorts report as being open on their websites.

On Friday, November 9, 2019, Breck’s website showed that Duke’s Run, Northstar, Pathfinder and Claimjumper were all closed.

Not so! Because at the top of Peak 8, I was physically there in-person: the rope was wide open and dozens of people were skiing down. The same was true the previous day when I skied “2 Lift Line” on Peak 8.

The opposite is also true: Ski resort websites shows a ski run open, I have taken as many as four lifts to get there, only to find the rope pulled and the ski run closed. Going to my iphone back to the ski resort’s website and the run still shows open, while I am physically at the trailhead of a closed run.

What I can provide however are ideas, clues, educated-guesses on when every single run at all of the above ski resorts will open, based on snowpack and to a much lesser degree, dates. However, just like Al stated earlier, there are many other factors too, such as wind, avalanche conditions, even if there is enough manpower on-staff to evaluate opening the ski runs.

My research is the early conception of potential future venture called Ski Run Forecast, that is currently a registered organization with one unpaid employee & CEO, named Mark Gerardy (that’s me!) without yet a website, but only a collection of data stored on a number of Excel Spreadsheets that can tell anyone the winter snow story of the 2018-2019 ski season. A vast array of other data exists with Joel Gratz’s OpenSnow.com, OnTheSnow.com, SNOTEL, Snowpak.com, Zrankings.com and many other websites.

My data however is not about how much snow fell, but focuses on when ski runs opened for the season and how much snowpack that it took to open each run, and on what particular date. I can sort and tell anyone which ski runs are likely to open next, in which order at any of these 21 different ski resorts.

Last season, Crested Butte opened the High Lift on January 7, 2019 with a 45-inch base and the North Face lift on January 12, 2019 with a 46-inch base, with most runs open. Last to open was Upper Banana (with 71-inches of snowpack) and Teo2 never opened. In the 2018-2019, to my knowledge, neither the High Lift or the North Face Lift opened – both remained closed for the entire season, which means that nearly 50+ ski runs were affected.

I can tell you that Taos needs a 45-inch base before they are going to open Kachina Peak (or at least all of it and the chutes). So if Kachina is not yet open, but they are sitting at a 42-inch snowpack, and you see three storms descending on Taos within the next two weeks, then I can tell you that you can be fairly-confident that Kachina will probably open before your planned trip to ski there three weeks from now.

However, if Taos has dismal snowfall, like during the 2017-2018 ski season, then don’t be making any plans to ski Taos, if hucking off Kachina Peak is on your bucket list. I found that out the hard way, having driven all the way to Taos in 2016 and then cancelling another trip in 2018 due to lack of snow.

An example

I see pre-season anxiety all over ski resorts Facebook pages: When are you going to open this run, this peak, this lift?

By the end of the 2018-2019 ski season, after spending 1-4 hours every single day combing through 21 ski resort websites, I finally have these answers, at least historically for the 2018-2019 ski season.

I will again be tracking most of the same ski resorts and validating what I found to see if the 2019-2020 is the same, or at least similar.

If I observe the Arapahoe Basin ski patrol opening Upper East wall when there is only 30 inches of snow reported at the ski resort, then I will quickly realize that my Snowpack Threshold Theory is debunked. But if I see anything close to last season’s threshold number of 55-inches to open Upper East Wall (except for Corner Chute and Willy’s Wide, which required 61-inches of snowpack to open), then give or take 3 to 5-inches, then I might be on to something that might have some value to quash some of that pre-season angst.

My objective is provide a forecasting service for snowsports enthusists to have the information regarding anticipated terrain openings. This allows for you to be poised and ready to get first tracks on the initial rope drop, just as terrain first opens for the season.

I am avid enthusiast and have long-since been a paid-subscriber to Open Snow, and read every word, of every post, that C.E.O. Joel Gratz writes. Open Snow is the premier resource to give you the tools to plan your powder days by tell you how much snow is going to land on the entire ski resort.

However, you cannot ski these epic lines and ski runs if they are still closed by the ski resort’s ski patrol, regardless of how much snow is on the ground or even in the air about to hit the ground.

My effort is to tell you when the specific runs themselves open, which is a different metric and different set of data – than how much snow that the entire ski resort is going to get.

This is my first official pilot post publically introducing the snowsports community to my past efforts and possible future endeavors.

Just like Open Snow, or your local weatherperson on television, no one can make guarantees, only forecasts based on historical data.

I have collected that data, this next season serves to validate that same data and determine if it is useful. In later ski seasons, this initiative has the potential to morph into a ‘WEATHER-BASED CONDITION FORECAST REPORTING SERVICE FOR AN OUTDOOR SPORT’, starting with Thrill of the Mountain, then to a dedicated website, then to an Mobile App.

This type of service started with Surfline in 1985 as a hotline for surfers to obtain the best surf conditions and go where the best waves are breaking.

While ski resorts provide Open Terrain reports on their website, after the fact, after ski runs are already open – until this point, there is no service that can tell anyone which ski runs are ABOUT TO OPEN SOON, and my effort work to close that gap, provided that there is a market of skiers and snowboarders who want to know.

Telluride’s Palmyra Basin has a tiny window of opportunity to ski, making it incredibly difficult to plan a trip to ski there, if your goal is to ski this extreme terrain.

Last season, even with non-stop snow, it was not until February 27, 2019 that Palmyra Basin opened with over 5 feet of snowpack. It was not long before Palmyra Basin closed in March, leaving only a few weeks window of opportunity to plan that ski trip to Telluride to hike Palmyra Peak for that once-in-a-lifetime epic line that you may never see again. Most of the time, Palmyra Peak never opens. However, after a season of data collection, I might be able to clue you in on when Palmyra Peak might open, based on the current trajectory of seasonal snowback and the snowpack threshold that it is going to take for the Telluride Ski Patrol to open these runs. I can help you plan your ski vacation to be at the right place, at the right time, when your favorite ski runs are projected to potentially open – and hence: SKI RUN FORECAST.

I can forecast when individual ski runs at 21 different ski resorts are most likely to open, based on the snow that is already on the ground and the snow that OpenSnow.com’s Joel Gratz and the local news tells me that is on the way.

Answers to when some of these ski runs are going open that folks stated that they are excited to ski or board, based on when the snowpack is reported:

Lone Peak- Big Sky: The first runs started to open on Lone Peak on Thursday, November 22, 2018, in which there was a snowdepth of 22-inches at the base of the mountain. Big Sky posts three measurements: Base, Mid-Mountain, and Top. Intermediate run Upper Morning Star was the first ski run to open and the 23rd ski run to open at Big Ski for the 2018-2019 ski season, with only 8% of the mountain at 445 skiable acres open. By Saturday, February 9, 2019, with an 83-inch base, then 100% of all runs on Big Sky’s Lone Peak were open for the season, which amounted to 301 of 307 of Big Sky’s terrain. The following ski runs on Lone Peak are volitile, with frequent openings and closes: Castro’s, Dirt Bag Wall, Great Falls, King, North Summit Snowfield, Orbit, Otter Side, Rips, Tears, Trident, Vuarnet Cliffs and Wave. Orbit and Trident were the very last to open. Coveted extreme ski run Big Couloir (that requires folks to have a beacon, probe, shovel, partner and be signed-out at the ski patrol shack) opened on Friday, December 21, 2018 as confirmed in-person on that very day, with a 44-inch base at the summit. It was not until Friday, January 4, 2019, that Big Couloir was consistently-open, with 31-inches at base, 36-inches midmountain and 54-inches at the summit.

Powerline Glades-Snowmass: Powerline opened on Wednesday, November 21, 2018 with Snowmass reporting a 23-inch base. It was the 15th ski run to open for the season with 17% of Snowmass ski runs open and 572 skiable acres.

Far West-Copper Mountain: Far West opened on Saturday, December 1, 2018 with a base depth of 30-inches and was the 90th ski run to open at Copper, with 57% of their terrain open and 1,405 acres. Far West was incorrectly reported on the Copper Mountain website on November 25, 2018.

Imperial Express- Breckenridge: Imperial Lift, Imperial Bowl and Imperial Ridge opened on Thursday, November 22, 2018 with a reported snow depth of 27-inches, the 65th ski run to open, with 44% of the mountain open and 1,294 skiable acres. Whale’s Tail opened on Thursday, November 29, 2018 (as observed in-person at the season’s rope drop) with a 35-inch base, the 93rd ski run open – but was not officially reported on the ski resort website as being open until Friday, November 30, 2018. On Saturday, December 1, 2018, George’s and Boundary Chutes both opened, with 40-inches of snowpack. Lake Chutes opened on Friday, December 14, 2018 with 39-inches of snowpack and the 169th ski run to open at Breckenridge, with 86% of terrain open and 2,503 skiable acres. On Friday, December 21, 2018, Snow White opened for the season, with 44-inches of snowpack, the 177th ski run to open for the season, now 94% open and with 2,745 acres to ski.

Thunder Wolf lift-Big Sky: Thunder Wolf Lift opened on Saturday, Decvember 15, 2018 along with runs Bighorn, Elk Park Ridge, Madison Avenue, Crazy Raven, Wolf Den and Wolverine and with a 40-inch snowdepth.

Coombs-Jackson Hole: Coombs opened on Sunday, December 16, 2018 with a 42-inch snowback becoming the 64th ski run to open at Jackson, with 47% of their skiable terrain open and 1,175 acres.

Rock island-Snowmass: Opened on Thursday, December 27, 2018 with a 40-inch base, the 91st ski run to open, 97% of terrain and 3,229 skiable acres open.

Christmas Tree [Bowl]-Steamboat: Opened on Sunday, December 2, 2018 with a 46-inch snowback, the 99th ski run to open for the season, with 67% of the mountain open and 1,987 skiable acres of terrain open.

Cirque-Snowbird: Upper Cirque, Middle Cirque, Lower Cirque, Cirque Traverse opened on Saturday, December 8, 2018 with a 46-inch snowpack, the 73rd runs to open, with 43% and 1,086 skiable acres open.


I do not expect to be earning any income on this venture for many, many years, but in the distant future, who knows? Open Snow.com started from humble beginning too, with an online blog just like this one, called Colorado Powder Forecast. Today, Open Snow reaches 2.5 million people, has a small staff, and provides the snowsports community an invaluable resource.

Objectives of Ski Run Forecast:

The objective here is to have a tool to assist in making travel to ski resort destination decisions. The objective is not to be exact, precise, or always accurate – but only to provide the best data and let the skier or boarder ultimately decide his/her travels based on what runs, or area of the mountain, that each person wants to be open to ski or board and when they might be opening for the season.

Until the above goals become reality, I can share what I know here in Thrill of the Mountain blogs. I can forecast which ski runs have the potential to open soon.

If you like to ski or board the most challenging and technical lines, you understand that the most advanced terrain typically is the last to open for the season, but sometimes has a narrow window of opportunity to be able to ski or board.

I want to plan my ski trips to coincide with when the terrain that I want ski is likely going to be open. I want to share this information, so tha the right people, get to ski what they want, as soon as they can.

Now the challenge is taking all this raw data and developing a service, eventually a service that can show a profit through advertising dollars. Hopefully some of the information that I already provided might be useful to you to plan some of your winter trips.

If you share my enthusiasm, then please comment and tell me. Even better, let me know if you if you would like to team up with me to help me develop  and provide this service to the skiing and snowboarding community.

Comment and tell me what ski runs and which ski resorts that you are excited to ski this season?

You can reach me directly at mgerardy@gmail.com.


  1. A very thoughtful, personal & in-depth analyzation of how ski areas determine when snow depth is adequate to open runs to the public skiers & riders. Great research, Mark! From the curmudgeon in me: I’ve seen awesome powder runs scraped to crust in an hour by novice board skidders 🙁

  2. PS- You forgot to mention two of my favorite runs: 5 mile long Riva Ridge at Vail & Regulator Johnson at Snowbird ( I was fortunate to get front row on a patrol rope drop, bluebird powder day 25 years ago!)

    1. Snowbird’s Regulator Johnson opened on Sunday, November 25, 2018 with a 36-inch snowpack, the 10th ski run to open at Snowbird, among the first 6% of the ski runs to open when only 149 acres are open at Snowbird, and one of the main arteries from the Snowbird Tram. Interestingly-enough, I found myself skiing Snowbird on Thursday, January 24, 2019, just after 6-feet of new snow and extremely high winds which had shut down much of the ski resort. After arriving at the top of the Tram, Regulator Johnson, a single black diamond run, during Thursday morning, was the ONLY ski run open. I overheard some beginner, early intermediate skiers, a man & wife couple from the MidWest, talking with the ski patrol about their dilemma, as they lacked the skills to ski the only run open at the top, Regulator, a single black diamond run. Meanwhile, I decided to click-into my skis and depart while they all figured that situation out. The next tram ride later, the same people were apparently marooned at the restaurant at the summit, and I was able to get to ski Great Scott, which had just reopened, and I posted my video dropping in and whitewater style riding a sluff of snow river down the run. Snowbird, many of the Utah ski resorts, as well as especially the Tahoe ski resorts, and Taos, can get pounded by high winds that have no mercy, and can shut down 90% of the ski area. While the Falcon chair at Breck’s Peak 10 can certainly get shut down too, as well as the T-bar and Winter Park’s Panorama Lift – these winds are breezes compared to what I have seen happen in other places. On January 6, 2019, Snowbird reported their previous 160 out of 165 runs open to only 106. The following day, only 54 runs were open, with winds reported from 42-68 mph. It is a signpost to folks to look at not just snow forecast, but wind forecast, especially in these areas, as winds above 40 mph will start to shut everything down quickly.

    2. This season, I will start tracking Vail, as I know that not having any data on Vail makes this conspicuously-absent. Not to sound negative or like a Debbie-Downer, but Vail’s parking situation makes Vail less-than-appealing for me: the long walk from the parking garage to the nearest lift. Certainly, Vail has some incredible terrain and many good things about the resort. Nonetheless, in the future, I am going to focus on all the positives that Vail has to offer and find my way clear to endure the trek from parking garage to lift, maybe asking around if anyone has a golf car with snow tires that might be willing to give me a ride from the parking garage to the lift for another $20 or so. 🙂

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