The NOAA winter forecast was released last week. They say,
For the second winter in a row, La Niña will influence weather patterns across the country, but as usual, it’s not 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 temperatures this winter.
Overall, northern Illinois is expected to have increased odds of being colder and snowier than normal – similar to last year. Here are the details. Below the forecast is a refresher on the winter of 2010-2011 that we all knew and loved.
Temperature:
For Illinois, the northern third of the state is expected to have an increased chance of below-normal temperatures. The southern two-thirds of the state has equal chances of above, below, or near-normal temperatures.
Precipitation:
Almost all the state, except for far western Illinois, is expected to have an increased chance of above-normal precipitation. Far western Illinois has equal chances of above, below, or near-normal temperatures. Although NOAA does not offer a winter snowfall forecast, increased precipitation in the winter months usually means increased snowfall.
Winter of 2010-2011
Here are the temperature map and snowfall map for the Midwest for the winter of December 2010 to February 2011. Both maps are expressed as departures from the 1971-2000 averages. The winter was both colder and snowier than average across the Midwest. Meanwhile, precipitation (rainfall and the water content of snow) was right at average for the winter.