ESPN Freeskiing

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Forever in search of the perfect storm, however imperfect, ESPN Freeskiing perked up this morning when an email showed up from Joel Gratz. It was 10:08 a.m. Aspen time.

Subject line: "Colorado Powder Forecast, 10/27/2009: I Hope this Storm Can Dance."

Three hours later it started snowing. At 3 p.m., the Colorado Department of Transportation closed Independence Pass "temporarily," which here sometimes translates to "all winter."

This storm isn't some isolated cell. It will be felt across the entire U.S. Rockies, dropping snow from Canada to Mexico, with north-central mountains of Colorado expected to bear a brunt of 1-2 feet (!), according to forecasts. Back to Gratz's email. A meteorologist, Gratz is author of coloradopowderforecast.com, a website (launching today, actually, with any luck) that has grown out of regular email-blast-style forecasts by Gratz, like this morning's:

"First," Gratz writes, "think of a big snowstorm like hanging out romantically with a member of the opposite gender. Even if 90 percent of the experience is awesome, that final 10 percent can be a deal breaker. It's the same story with this storm. Everything looks like it's coming together for some sweet snowy goodness..."

Later, we got Gratz on the phone to discuss scenarios like these, plus the new El Nino special at Taco Bell, the difference between jet streams and Pineapple Expresses, and why weatherman don't share the media's love affair with the term "Perfect Storm."

ESPN Freeskiing: Love storms, love 'em. Is this the big one?

JOEL GRATZ: "It's a powerful storm, very similar to what we'd see in the middle of winter in Colorado, but not so normal for the month of October. Powerful storm, good storm and slow storm—it's gonna take a good two days to clear Colorado to Kansas—and all that equates to a good shot of snow."

Why this October? "It comes back to the jet stream. This summer and fall the jet stream has been farther south than normal, and that's why we're seeing more storms here in Colorado in the early season. It's also very typical of an El Nino year."

Nice Halloween custome idea. Thanks. "Yeah, El Nino. He's when the Pacific Ocean measures .5 degrees Celsius warmer; when it's .5 degrees colder, it's La Nina. El Nino has effects all over the world, but here it works to pull the jet stream further to the south. And that's what we're seeing."

When did we last see this El Nino fellow? "The last pretty good El Nino was 2002-03, but the last time was 2006-07, and it didn't get going until late summer 2006. El Nino takes a while to influence the weather. It's not like the day the ocean warms up above .5 degrees on average that weather changes around the world. No, it takes a while. But this one here started late spring, early summer, so it's had a couple of months already to start entrenching itself in world weather patterns. And now that we're reaching fall El Nino is having an effect—it's already been around for a few months already."

"Later, it should also pull the storm track further south than normal—California, Arizona, New Mexico—and start hammering places like Mammoth and Taos."

So who's getting crushed... now? "This storm is basically gonna take its sweet old time tomorrow to work across the area, but the heaviest snow for areas south of I-70 is gonna be mostly done by midday tomorrow."

Boo. "Most of the mountain areas in Colorado could see a foot of snow, but the best shot for the big time amounts is gonna be along and north of I-70 and along and north of the Continental Divide; Rocky Mountain National Park, Berthod Pass, Indian Peaks. Areas like Loveland and A-Basin will do well, but there probably wont' be the killer amounts; it's gonna be further north in backcountry areas."

Yay. "Man, I wish this were January dude. I wish we had a nice stable base and we could crank out some big totals. But unforantely it's looking like this is just gonna make the avalanche danger go off the charts."

Boo. So does this storm have a nickname. Pineapple Express? Something? "I don't think so. The Pineapple Express is this vague reference to tons of moisture coming off the Pacific, which is usually warm compared to air coming down from Canada, so that's good verbage for that type of pattern. But this one is just a strong, slow-moving storm that's carved out a big trough, a big dip, in the jet stream and it's not going anywhere anytime too soon."

"It's snowing all the way north as Montana to the border and it's gonna drop snow all the way down to Arizona and New Mexico; it's gonna snow from border to border. But the center of it is moving right across southern Colorado and the heaviest snow totals will be the area we talked about and up into southern and eastern Wyoming. ... Denver could see over a foot. That's a pretty good forecast there if all things came together."

Two part question: Do weathermen like the term "perfect storm?" Part II: Is this a perfect storm or an imperfect storm? "I think [laughter] weather folks are cautious to use the term perfect storm. Because there are few storms in a lifetime that really deserve that kind of name. This is not one of them. This is an important storm because it may set the snowfall record in Denver for October, but it's likely a big-time October storm that'll likely be remembered for a long time. And it's also special because it's early season and we don't often get storms like these that flank the entire state in storm. But is it a storm that's gonna give us a gift-of-a-liftetime-type of storm? I don't think I'd say that."

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