“I get all the news I need from the weather report.” —Paul Simon
There’s a particular tree, a big cottonwood, that grows on the side of the main road in my hometown. We call it the Snow Tree and it’s said that the first snowfall won’t come until it loses all of its leaves. I trust that tree more than I trust rumors of El Niño, especially in summers like this one when predictions of El Niño are rampant. I realize I might be a little jaded—as a skier in California, I’ve learned to be skeptical until there’s fresh snow in the driveway. So I called a forecaster I could trust, Joel Gratz, of OpenSnow.com, a skier’s kind of weatherman. Here’s what Gratz had to say about the winter ahead. (Although I still have more faith in that tree.):
Joel Gratz: To get this out there right off the bat, long-term forecasts are generally pretty terrible. I don’t find them of great use for most skiers, as in, you really can’t find powder days by looking at a long-term forecast.
Got it, we shouldn’t quit our jobs to ski all winter just yet. Now, what’s the deal with El Niño?
Here’s a little primer on El Niño. It’s talking about ocean temperatures in the central Pacific, loosely between South America and Indonesia. That’s the region of the globe that you’re looking at when you’re talking about El Niño or La Niña. The reason that that matters is when those water temperatures are well above average or well below average, that actually changes weather patterns around the globe. And it changes things with some level of predictability.
It seems like I hear something about El Niño or La Niña every year.
Here’s the deal, it’s a cycle. For the past 50 years, a third have been El Niño, about a third have been La Niña, and a third have been neutral. So you’re right, two-thirds of the years, you’re probably going to hear El Niño or La Niña.
It’s almost like a powder day. There’s different levels. There’s dust on crust or deep blower awesomeness, and same goes for El Niño and La Niña. It’s about how far above or below average the ocean temperatures are.
So what are the oceans telling us now?
Back in the spring, there was a push of warmer water in the ocean, the wind switched a little bit, and those things are kind of rare. Earlier this summer there was an 80 percent chance of an El Niño year. Now, most recently, about a week ago, that’s dropped to 66 percent. It doesn’t seem like that big of a chance. But you look at the trend and this time of year, August into September, is when you trust the predictions of El Niño a little more.
But what does this actually mean?
That’s about where the snow is going to fall. The stronger the El Niño or La Niña, the more pronounced the patterns of snowfall. Let’s assume that we’re going to have some type of El Niño this year, weak or moderate. What that generally means is that the southwestern U.S. sees above average snowfall—Southern California, Arizona, southern Utah, southwest Colorado, the San Juans.
So the places that have had bad years the past three years will finally get dumped on?
The atmosphere has an odd way of evening itself out over the years. You can get terrible droughts or terrible floods. Look at Colorado, you had two bad years and the last year, it’s above average. It’s interesting how these cycles go.
Any other less scientific ways to predict snowfall?
I had a guy last year who is actually a specialty food distributor in Denver and he’s all about the mushrooms, high end mushrooms. Late last summer, he said there were fantastic mushrooms in Western Colorado. And he said the last time that happened, we had a big ensuing winter. That actually worked. And it’s not all that unscientific. There’s a correlation between late summer rainfall and a big winter.
I know you can’t guarantee a record winter at my home mountain, but any other last thoughts to leave us with?
I will leave you with two points. There are other seasonal factors that come into play. The Arctic Oscillation, abbreviated to the A.O., and the Pacific Decadal Oscillation, the P.D.O. These things are kind of like El Niño in that they help drive weather around the world. El Niño is the big one that we look at, but it’s not the only one.
Second, all of this is really fun and well and good, but once we get into the season, you can look at the weather pattern 7 to 10 days out and start predicting weather. Think about taking time off work to hit a pow day 3 to 5 days in advance. But it’s not really until 2 to 3 days beforehand when you can feel good about the powder day. It’s really fun to talk about this because, what else are we going to talk about now? But once we get into the season, all that stuff we said back in June won’t matter.