What Will Winter Bring?
“La Nada” Leaves Winter Weather Forecasting in the Lurch
For those asking, “Where’s our winter?” the answer came in the first week of December as valley locations in North Idaho and western Montana received their first significant snowfall totals, followed by below freezing temperatures. Winter—at least, a typical winter weather pattern for our location—came late, but will it stay? What’s the prognosis for the next few months?
The answer from the experts at NOAA’s National Weather Service Climate Prediction Centers is... we’re not totally sure. Or in their own words, there’s “a high degree of uncertainty... .”
Not that long-range predictions of weather are ever totally sure, but this year the predictive models are shaping up to be more difficult than most. As Paul Hutter, a weatherman for Minnesota’s National Public Radio puts it, “There just isn’t any clear, distinct trend or data to hang your weather hat on this winter.”
Part of the problem is a shape-shifting El Nino. Mike Halpert, Deputy Director at NOAA’s Climate Prediction Center, tells us this winter season is “totally unique in the 63 years we’ve been keeping statistics on El Nino. Never before has an El Nino event begun to form in July and August, then quit in mid-September.”
For those who’ve forgotten, sea surface temperatures in the equatorial Pacific Ocean are major drivers for winter weather in the U.S. and across the globe. Unusually warm ocean temperatures, called El Nino, tend to drive warmer, drier winters in our piece of the global real estate. The opposite, La Nina, is a major cause of colder, wetter winters in our region—La Nina conditions have prevailed in the past two winter seasons.
Currently, a transition to El Nino conditions is stalled, and we’re in what NOAA calls an El Nino Southern Oscillation-neutral status, (more colorfully called a “La Nada”) which is expected to continue through next year. What that means for weather is that Pacific ocean temperatures are not expected to have, in our region, any change-inducing impact—our winter, in terms of temperature and precipitation, will be roughly average, with actual weather driven by other climate factors which have only short-term predictive ability.
“Idaho should have the best chance at being normal in the rain and snow department, but temperatures should end up below normal,” is the winter forecast from neoweather.com, whereas the National Park Service (http://www.nps.gov/klse/naturescience/weather-statistics.htm) is guessing our winter will be both colder and wetter than normal.
This is the guess from local weather expert Cliff Harris, as well, whose weather website (longrangeweather.com) is currently predicting a slightly colder and wetter winter season as well.
The North Atlantic Oscillation is showing signs of going negative, which brings cold air down from Canada into the U.S., and if it does, chances are good for typical winter weather through Christmas. But the NAO fluctuates quite a bit, and is therefore generally only good for predicting weather trends a couple of weeks out. If it flips positive toward the end of the month, we might well usher in the new year with unseasonably warm temperatures.
Harris is predicting the coldest weather for our area will fall during the full moon cycles (near the end of each month Dec-Mar) of the next couple months, with the heaviest periods of rain and snow during the middle and end of those months.
Forecasts on Harris’ website for Sandpoint in the first quarter of 2013 follow this pattern, though the difference from normal is slight, with temperatures no more than a degree or two below normal, and snowfall no more than an inch or two above normal. Weather stations for Bonners Ferry, Cabinet Gorge, and Trout Creek (Montana) are similar, with just a bit more snow at Cabinet Gorge and Trout Creek.
My own prediction for this winter’s weather, which is based on a completely non-scientific, pessimistic outlook, is for snowfall to come in periodic, massive dumps—as opposed to small, regular amounts—because this adds excitement to the winter plowing/snowblowing regime. Expect that snow to be fairly wet, at least at lower elevations, because that makes it more difficult to move.
I don’t look for long, sustained cold spells, but I do expect the weather to be cold enough to deplete my woodpile long before winter is over, despite the fact that my wood pantry currently looks sufficiently full.
Finally, my memory insists that we had much more wind this year than normal, so I expect that trend (whether it actually exists or not) to continue—mostly because I don’t like wind.
In a few months, we’ll know how well pessimism stands up next to science. Until then—bundle up!