A few people have asked about the weather data that shows on Crystal Mountain’s main webpage, why the numbers are sometimes screwy, why the snow depths don’t match their own experience, etc., etc., etc. Let me explain….


First off, let me clear up a common misconception. Ski Area snow reports—at least the ones I’m familiar with here in the Cascades—are generally NOT made up by Marketing Departments. They’re made up by machines. Cold, indifferent, machines.

Yeah, yeah, yeah, everybody knows somebody who gets all “Conspiracy Theory with Jesse Ventura” about some sketchy friend-of-a-friend who claims to have worked in ski area marketing one winter, and brags about the morning they were so hungover they over-slept and just made-up random numbers on the morning snow-phone recording.

That probably happens, but it’s pretty rare. I’m sure Justus only does that 6 or 7 times a season. (Insert winky emoticon here!)

But seriously, that’s not how it works.

How do I know?

Well, I know because the telemetry instruments that send the Green Valley and Base & Summit automated weather measurements out to the internet always seem to be RIGHT in my way when I’m trying to heat up my lunch! The microwave oven used to sit right in the middle of the counter at the Summit House patrol station. But now it seems, every summer the Northwest Weather & Avalanche Center (NWAC) folks add more and more sophisticated telemetry instrumentation that has to be hard-wired into the T-3 line or something, pushing the microwave farther and farther down the counter. So now it’s like a crazy awkward yoga move every time I wanna pop-in my Lean Cuisine.  Sheesh! Could they make my life any more difficult?

Anyway, so where was I?

Have you ever looked at Crystal Mountain’s Facebook Fan page? You’ll see “Saturday ROCKED, with cool temp’s and face shots all day!” right next to “Saturday SUCKED, it was freezing and I couldn’t see a thing! ”  (By the way, Buck Up you silly haters that call yourselves "fans"!  I recommend you spend more time skiing & riding so you’ll be cheerier and won’t have to spend so much time grouching on your keyboard!) 


My point here is that in an expansive ski area right on the crest of a continent-defining mountain range, and just inland of a humongous volcano, conditions are going to vary from spot to spot. Since Crystal’s website developers have no way of knowing exactly where YOU’LL be making YOUR turns each run, each day, they integrate impartial measurements feeding straight from the NWAC, to show what the weather generally is in the area. The data is collected NOT for marketing or website purposes. The information is collected for forecasting avalanche hazard.  It comes from “Snow Science Study Plots” where the machines take the mechanical and sonic measurements that are available to us all via the internet.  (Click on "telemetry" links below for examples.)


Base Weather Plot (telemetry)


Green Valley Weather Plot (telemetry)


The reason the numbers sometime seem completely wacked, is that machines can sometimes be tempermental beasts.  When things aren’t all working exactly right, the little database converter software thingy can borrow numbers from an adjacent column for the column that’s not working correctly and everything appears way off . So if the overnight snow depth shows as 270 inches (which is actually the wind direction blowing from the West as measured in a 360 degree clockwise circle) you know something’s up electronically, and it’s not the Marketing Diva’s trying to trick you!


Wind and snow settlement also play a role in your perceiving snow depth different than science does.  I’m going to explain this more in a future post, but basically it works like this: 

  1. The wind picks up the snow in some places and drops it in others.  If you were to probe to the ground in Powder Bowl, you’d find 1 meter of snow on one side and 2.5 meters on the other.  And you’re worried about a difference of 2" on the morning snow report???  We had 112 mph winds here a couple weeks ago!
  2. Settlement is the tendency of air to leave the snowpack as it sits over time.  Ski areas all measure "snowfall" which may be different than the depth of the "snowpack" at the time you pass over it.   It’s just how it’s always been done.


Stay tuned for part 2 which will explain how to use the telemetry to pick where you ski/ride on a particular day!


And please consider donating to the Friends of the NW Weather & Avalanche Center, an organization that helps support and promote the nice folks who’s work prevents avalanche accidents and makes my lunch hard to reach!



  1. Thanks Corey.
    Of course Crystal would never be guilty of exaggerating.
    However, conspiracy theories and Jessie Ventura aside, on Friday, January 29, 2010, The Washington Post recently reported ( on a study done by two economists, Jonathan Zinman and Eric Zitzewitz,
    “skiers who took offense to a fluffed-up claim, studied snow reports from 2004 to 2008 and compared them to area government weather stations. They found that ski resorts across the U.S. and Canada reported more fresh snow – 23 percent more, on average – on skier-coveted weekends than during the week. Resorts with more business to gain were the ones most likely to boast of deeper snowfalls.”
    The good news is that at ski areas with cell phone reception, exaggeration falls off sharply.
    Thanks Keith! Yeah, part of the reason I wrote the article is so people know that ’round here, it’s not some guy outside with a yardstick, like those “researchers” suggested. Snow depth is measured by a device that essentially sonar. At Crystal, patrollers also confirm the electronic measurements via 2 manual stakes–storm & 24-hour. Even though they’re only a foot or two apart, they sometimes will differ from each other by 2 or 3 inches. Settlement? Wind? Sunlight? That’s the nature of science!
    Speaking of which, I put “researchers” in “quotes” because….really? Disgruntled skiers are doing the research? Hmmmm….are we sure they’re impartial?
    They may be correct, but I’ve heard from patroller friends that one of the challenges in the Rockies–well, at least in the area around Aspen–is that often the snowfall occurs overnight, so by the time skiers & boarders are on the snow, several hours worth of settlement have occurred. I’ve seen the stats but never heard the explanation. Anybody out there with more weather knowledge than me know why this is?


  2. Thanks Corey. I notice that when Crystal started using the NWAC measurements that they usually under report the new snow if anything. An 8″ dump many times means a day of boot top to knee deep in our usual stashes. However, the marketing department descriptions are another story. I guess anything could be considered “snow off-piste is skier packed powder”, even if it’s melted in the sun, had a little rain, and then the refroze into crusty glop. The nice thing about being a Crystal regular, once you learn to read between the lines, the reports work quite well. The NWAC telemetry and patrol reports are invaluable. The best indicator of a good day is arriving in the parking lot at 7:30 to the sound of explosions on the mountain.


  3. Peter

    It would be really cool if you could rig up one of these:
    Corey Responds:
    Thanks Peter! That’s kinda neat, huh!
    But the telemetry can’t really lie, and anyone who doesn’t trust our numbers probably wouldn’t trust us to not photoshop in screencaps of huge snow totals.
    Still, that camera must make ya’ happy when ya’ wake up to unexpected dumpage. I’ll pass the idea on!


  4. Gus

    corey…thanks for this little article on weather data…i came across it while trying to find some info on how to read the telemetry reports. in part two can you explain the data shown, what unit of measurement (metric or silly american) and how to read the reports…i can’t find anything on the web about it. thanks!


Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Google+ photo

You are commenting using your Google+ account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s