Skiers and riders, start your engines. Just know you may have to idle for a while before La Nina throws it into high gear.

La Nina is an abnormal pattern of ocean temperatures spanning the equatorial Pacific Ocean. Seems bizarre that THAT could be our best predictor of Cascade seasonal snowfall, but, it is, and it’s fairly reliable. In a sentence, oceanic heat content is linked to atmospheric circulation patterns, especially in winter. When warm water piles up in the western Pacific, it tends to promote a jet stream pattern that brings a lot of cold storms to the Northwest. More on that in a bit, but here’s how I see the season shaping up.

I won’t be surprised if it’s a slow start to Cascade snow pack. Skiing by Thanksgiving? Could go either way. But Christmas and beyond should be epic. In some ways this season’s La Nina signal resembles that of 2008-2009, in that we came out of a strong La Nina the previous year (2007-2008) and transitioned into a No Nino or weak La Nina for 2008-2009.  Remember Arctic Blast? Make sure you've got good tread on your ride as I think the lowlands will see a few good snowfalls this winter too.

Here’s the monthly snowfall at Government Camp (4,000 FT) for the 2008-09 season:

2008 November    17”
2008 December    104”
2009 January        41”
2009 February       51”
2009 March          108”

So don’t be afraid if the season starts slowly! But La Nina likes to keep our powder dry and deep well into spring. It should be a long season!

One of the questions I get asked a lot this time of year is “where should I plan a ski vacation?” I wouldn’t venture too far from home this season. La Nina’s tend to bring big snow to the Northwest and BC, but as you head south and east, the snowfall can become sparse. That said, each La Nina is different from the next. Remember the massive snowfall in the Sierra Nevada last year? Mammoth Mountain saw several four-foot snowfalls and the Tahoe area had so much snow they skied into 4th of July.  But that’s unlikely to happen two years in a row.  And even though there’s no guarantee (even La Nina can be a bust) above average snowfall is more likely here than any other region of North America. For a look at the National Weather Service’s Climate Prediction Center’s long-lead seasonal forecasts, click here.

The other question I get asked a lot is “should I buy a seasons pass?” Umm, yeah, if you can make use of it, this would be a season to plan on a lot of great ski days. And plan on having some ready-made excuses to call in sick when you get hit with the “foot new flu”.

So get ready, lovers of snow, speed, gravity, anti-gravity and powdery peaks, it should be game on this year! Hit the sales, hit your ski leg work-outs to help minimize the threat of a season-ending injury, and be ready to take time off from work. I’ll be blasting you with powder alerts when we start getting blasted with snow.

Happy Trails and Turns,

Matt Zaffino
KGW Chief Meteorologist

(Matt Zaffino has been forecasting powder days in Oregon for over 25 years. An avid back-country telemark skier, he’s hit the slopes of Oregon from his previous home near Mt Ashland to secret powder stashes in the Wallowa’s, while logging as many runs as possible at all of the resorts in the Oregon Cascades.)