Snow reports and resort data explained. We break down the most pressing and commonly asked questions around everyone's favorite topic: where are we skiing powder today?

Q: Where do we get our snow reports?

A: Snowfall totals, base depths, on-slope conditions, number of runs, lifts, acres and terrain parks open is 100 percent filed by the ski resort themselves or sourced directly from the ski resort’s website. Every open ski resort in North America will have an updated snow report every day; we'll also provide snow reports for closed resorts where we're able to find that data.

Q: How is base measured? Where is this measurement taken and why?

A: It’s complicated, and everyone has different methods. Here are a few of our favorite explanations:

A: Squaw-Alpine: We have a snow sensor that measures the height of the snow on the ground at the weather station at 8,000 feet. It takes a measurement every 30 seconds. The snow is not compacted in this area and it does not receive much sunlight, so it isn’t sun affected. We also have a manual snow stake that we can read the height on—we use that as back up and cross-reference. 

The measure is taken at the snow study site at 8,000 feet. It’s located along the expressway in a grove of trees. The trees help the wind from blowing the snow away and block some sunlight to avoid melting. We have been measuring the snow in this area for decades. We keep it at the same location so that we have accurate historical data.

A: Vail: The “where” is mid-mountain, on the front side of Vail Mountain. As you know, Vail Mountain's conditions can vary from one area to the next—front side to Back Bowls to Blue Sky Basin. Each resort has an official 'snow study area’ otherwise known as its official snow-reporting stake.

In Colorado, when Vail Resorts was part of Colorado Ski Country, the designation for mid-mountain was somewhere in the middle third of the mountain. According to that guideline, the stake must be located halfway up from the base, closed to the public, shielded from the wind, sited to avoid a canopy of trees and must be monitored by a camera. Again, at Vail, this stake is located in the mid-mountain area.

Vail’s security department is responsible for measuring, via camera, any new snowfall to the half-inch, posting and reporting the snow total and base every morning by 5 a.m. Security works hand-in-hand with ski patrol to clear the stake each day and ensure consistent snow reporting.

A: Killington: We don’t really have a scientific method of determining base depths; it is an estimate of depths on most open terrain. So, while our base depth on a snowmaking trail might be 10 feet in some spots, we will not report 10 feet as a max because in the majority of places it might only be 36". At the same time, we could have a non-snowmaking trail open that is “thin” in spots, but the majority of the trail is roughly 10" of base. Under this scenario, we would report 10-36" range on this. 

A: Park City: We take the average across the snow stake. You’ll notice that sometimes the snow will be higher on one end. To report an accurate number, we take the average across the stake at all of our locations. At this point, we are planning to take snow stake readings at four locations across the mountain: Summit House (9,300 feet), Jupiter Peak (10,000 feet), Dreamscape (9,200 feet), Painted Horse (8,600 feet).

A: Arapahoe Basin: We measure our base or HS at our ABVL weather station (we have three) which is located NE of the Black Mountain Lodge by about 450 feet and at an elevation of 11,493. On a daily basis (at 5 a.m.) we check the ABVL weather station and collect several manual observations such as: height of new snow (HN), height of base snow (HS), air temperature and water (SWE or Snow Water Equivalent) per SWAG (Snow, Weather and Avalanches: Observation Guidelines for Avalanche Programs in the U.S.) standards. In addition, this weather station has several weather instruments or sensors that electronically measure the aforementioned variables as well as relative humidity and pressure.

Q: How is settled base measured?

A: Park City: In addition to the 24-hour snowfall measurements, we also record the settled base snow depth each morning at 5 a.m. This figure is read from a permanent stake that measures height of settled snow above the ground. Reading this stake is a bit more complicated due to fact that a settlement cone typically forms around the permanent stake since heat from the stake itself causes the snow next to it to melt or settle faster than it would in a regular field of snow. Base depths are therefore read as the level of snow outside the influence of the settlement cone, or about two feet from the stake. To make this measurement consistently, the patroller averages the height of snow against the stake in front of and behind the stake.

A: Arapahoe Basin: As for a base measurement or height of snow (HS) we have a tall snow stake with one inch increments that we look at every morning to see what our base depth is. In addition, we also have sonar that measures this very same height of snow. We have to look at the height of snow daily because either it snows and increases in height or we receive no precipitation and it continually (the process slows) shrinks. This is known as settlement, which is a progressive densification or consolidation of the snowpack due to gravity, overburden pressure (other layers above) and metamorphism, which begins as soon as the snow falls to the surface. This is why when it snows 12 inches we may not see our height of snow increase from 60 inches to 72 inches for example. It should be noted that with lower amounts of new snow there may be an exact increase of base depth, but larger amounts like 12 inches will add significantly less. 

Q: Say it snows 6", how will that impact base depth?

A: Squaw-Alpine: Snow settles over time. The rate of settlement varies by factors like density of the snow and the intensity that the snow is falling. 

A: Killington: In this same scenario, if we got 6" of fresh snow, we would not necessarily increase our base depth, but we would increase our daily/season to date snow totals. It is truly an estimate of “average” coverage over all open terrain.

Q: Why doesn’t OnTheSnow match the ski resort’s snow report?

A: We work hard to provide up-to-date ski and snow reports on a daily basis, but sometimes there are discrepancies between our data and what the resort is displaying. This can be due to the fact that during a storm, the ski resort updates their website on a consistent basis while OnTheSnow displays one update per 24-hour period.

For instance, if a resort reports 6" to OnTheSnow at 6 a.m., but then updates their website at eight a.m. to 10", our snow reports will differ. That additional 4", plus anything else that fell between the time the snow report was filed and the time it’s filed for the next day will be reflected in the next snow report.

Accordingly, timing also has an impact. When we file a snow report for a ski resort, we record all the data as it’s been updated to that point in time.

Q: I just submitted a firsthand report via the app, why don’t I see it there or on the website?

A: All firsthand reports go into a queue that are then reviewed and approved/rejected by our content team throughout the day. Our edit staff is filtering for inappropriate imagery or language in the form of profanity, pornography, hate speech, etc.

Unique to the OnTheSnow App, firsthand reports and photos are designed to be a form of crowd-sourced ski and snow conditions and current on-mountain experiences—if a comment or photo doesn’t directly relate to one of those topics, it may not be published. In other words, trolls and haters need not apply!