Ask a meteorologist about a long-range winter forecast and their eyes will roll. Will the snow pile up in the East, as some sources predict? Will the East hold its own? What will La Niña do to us this time?
Joel Gratz, a meteorologist and die-hard skier who produces the popular OpenSnow website, says he wishes he could provide an accurate, actionable forecast for the upcoming ski season so all of us could plan trips when the snow is best. “Unfortunately,” he told SnoCountry.com, “long-range forecasts are almost useless.”
Why? Gratz says the accuracy of seasonal forecast is very low. “Short-term forecasts out to a few days or even one week have pretty good accuracy and allow folks to plan powder days, but the accuracy doesn’t carry over to longer range forecasts.
“Ski conditions are generally controlled by each individual storm, not by seasonal average snowfall. Often, a weather pattern can develop that will bring cold temperatures and plentiful snowfall for a few weeks. This might be a great time to ski or ride, even if the season as a whole is below average in terms of snowfall,” Gratz says.
With that caveat in place, Gratz notes that strong El Niño (warmer Pacific Ocean temperatures) or a strong La Niña (cooler Pacific Ocean temperatures) help make predictions a bit easier.
“This upcoming season is unfortunately going to be a La Nada, meaning the Pacific Ocean temperatures are about normal. Because of this, we can't make an accurate long-term forecast for snowfall for the coming winter.”
His best advice: “Start looking for the best snow at the 10-15 day forecast, but don't believe it or take any action until you're within about five-ish days of an upcoming storm. Then go chase the powder and enjoy that hot tub reward after a great day.”
SnowForecast.com Faces The Music
Chris Manly of SnowForecast.com told SnoCountry.com that last winter “was like a music concert where the performer didn’t even show up. Thankfully this year, after rehearsals, a new album –“Weak El Nino and the other factors”— sets the stage for a more enjoyable performance for most of the country’s resorts."
Manly says the Pacific Northwest is the opening act in late October with the jet stream pulling in frequent storms across the Cascades and northern Rocky Mountains. A large trough of low pressure drops farther south through the West Coast for the rest of October bringing early-season resort-elevation snowfall to Tahoe and Mammoth, California and Sierra Nevada Mountains.
Winter plays new album material in November, he says, in Southern California, northern Arizona, and New Mexico as storminess shifts southward for near-average temperatures and precipitation.
“Meanwhile, the eastern U.S. (Great Lakes, Mid Atlantic, and New England) are still finding their seats in the concert hall with slightly less precipitation but getting colder.
“By December and through January/February, the main act arrives as most of the U.S. and southern Canada turn colder than average along with near-average snowfall, with the exception of the Pacific Northwest heading to the concession stands (slightly drier). The East Coast may be rocking out to some coastal storms and near to slightly above average snowfall.
“March - spring plays a few throwback tunes (near average snowfall) for the Pacific Northwest and down through Mammoth/Tahoe while Southern California, southwest U.S. (Northern Arizona/ Southwest Colorado and northern New Mexico), plus New England receive above average precipitation and snowfall. April - Southern California, southwest U.S., Utah and Colorado should enjoy an encore of above average snowfall while the eastern U.S. heads for the parking lot.”
The Official Word From NOAA
The official forecast from the National Oceanic and Atmospheric Administration (NOAA) says that La Niña will influence weather patterns for the second straight winter in a row. But, they are quick to point out, it won’t be the only climate factor at play. The “wild card” is the lesser-known and less predictable Arctic Oscillation that could produce dramatic short-term swings in temperature over the winter months.
NOAA believes La Niña, which returned in August, will gradually strengthen and continue throughout winter. It is associated with cooler-than-normal water temperatures in the tropical Pacific Ocean and influences weather across the globe.
“The evolving La Niña will shape this winter,” says NOAA’s Mike Halpert, deputy director of the Climate Prediction Center. However, he notes that Arctic Oscillation factor could generate “strong shifts in the climate patterns that could overwhelm or amplify La Niña’s typical impacts.”
NOAA’s regional predictions: Pacific Northwest (colder and wetter than average); California (colder than average favoring wetter conditions in north, dryer in south); Northern Plains (colder and wetter than average); Ohio and Tennessee valleys (wetter than average); Northeast and Mid Atlantic (equal chances for precipitation and temperatures above or near normal). Areas north of Ohio Valley into Northeast could get above-average snow; Great Lakes (colder and wetter than average).
Stuff From The Almanacs
There are plenty of other forecasters out there. The Farmer’s Almanac (orange cover) says, “We think it will be a winter of contraries, as if Old Man Winter were cutting the country in half. The eastern half of the country will see plenty of cold and snow. The western half will experience relatively warm and dry conditions.”
The Old Farmer’s Almanac (yellow cover) basically agrees: “The 2013 Almanac says the temperatures will be much colder this winter from the East Coast westward to a line from Dakota to Texas. In every place west of the line, except for portions of the Desert Southwest, temperatures will be warmer than last winter.”
What It Means: Predicting weather is a lot like rounding up cats. Never easy, but we always get a taste of catnip in the air. Still, the consensus – if there is such a thing among meteorologists – is that the East has a shot at a very snowy – “one of those” – winters (go for it Arctic Oscillation) and, hopefully, the West dodges the bullet. Guess we’ll all have to wait and see.
Photo: Mountain High Resort