National Weather Service guru: “Uh oh, no Niño.”
Posted on October 7th, 2013 by edge | 2 Comments
This is the weather forecast we wait for every year. Despite being banned from the Colorado Snow and Avalanche Workshop (CSAW) due to the federal government shutdown, National Weather Service meteorologist Joe Ramey delivered his annual prediction Friday. He did this vicariously through Colorado Avalanche Info Center forecaster Jon Snook, who pinch-hit for Ramey at the annual gathering of avalanche pros.
“Uh oh, no Niño again,” Snook said to the crowd of several hundred. He said Ramey and his team at the NWS Climate Prediction Center depend on ENSO (El Niño Southern Oscillation) and PDO (Pacific Decadal Oscillation) trends to make their annual predictions. Southern Pacific surface water temps currently aren’t showing either an El Niño or La Niña weather pattern for the season. And PDO models show a cooling trend. Looking at historic weather patterns, this–combined with our current wet autumn–has correlated with below average snowfall in Colorado. But not extremely low, he pointed out. He said that in Colorado we can expect a snowy November into December, a fairly dry Jan/Feb, then the possibility of an El Niño pattern developing in March and April. Extrapolating on this, you can probably expect some pretty good mid-season snow in the Pacific Northwest, like last season.
El Niño patterns generally favor wet and cold conditions in the south and La Niña patterns generally favor wet and cold conditions in the north, with Colorado falling right in the middle. (Glass half-full: we have glorious sunny weather.)
Ramey nailed the forecast last year, predicting a non-Niño pattern with a wet December in Colorado and a snowy April. So he’s got some cred with the snow safety crowd. In fact, Snook told the crowd Ramey was extremely disappointed not to make the trip, as it’s a weatherman’s dream to revel in an accurate forecast.
How much can we really depend on this forecast? Snook used a dartboard analogy to gain some wiggle room. He said the forecast represents a slice of surface area on a dartboard. While it’s possible to throw a dart and hit anything on the board, the chances for non-Niño are a little bit larger than the chances for some other weather pattern: either one can happen, depending on where the dart lands.
Regarding avalanches, snowfall can be inversely related to avalanche hazard: the less it snows, the more unstable the snowpack, thanks to the faceted snow grains that can develop over long, dry spells. So in a low snow year, it’s more important than ever to make sure you’re equipped with an avalanche transceiver, avalanche probe, avalanche shovel, avalanche airbag–and, most important, an avalanche course.
Stay tuned for more CSAW coverage over the next few weeks, as well as other regional avalanche workshops from Utah, Montana, and the Pacific Northwest. And the second-ever European International Snow Science Workshop (ISSW Europe) started today in Grenoble, France.