Snowfall so far this year: 2.7 inches
Average snowfall for this point in the season: 11 inches
Average winter snowfall: 20.8 inches
Least snowfall in last 100 years: 3.5 inches (2005-2006 winter)
Most snowfall in last 100 years: 54.9 inches (1977-1978 winter)
COLUMBIA — The National Weather Service says snow is likely Sunday through Tuesday, but this could be only a symptom of a shift in a weather pattern that's made for a relatively cold, dry winter.
The arctic pattern that has meant cold and very dry polar air for much of the winter was shifting late this week to a more zonal pattern that's characterized by systems moving from the west that could bring moisture from the Pacific and Gulf of Mexico to mid-Missouri.
The jet stream, a fast, high-altitude, eastward-moving wind current whose path is governed by everything from ocean currents to the rotation of the Earth and wave mechanics, acts as the barrier between cold arctic air and warmer subtropical air.
When the jet stream dips south, arctic air envelops Columbia; when it flows to the north, the air can be warmer.
"What a zonal pattern will do is keep us from seeing the waves of dramatic temperature changes that the arctic pattern brought us," said Benjamin Sipprell, a meteorologist with the National Weather Service in St. Louis. "We will have to keep our eye on things as we get into February."
With less than two months to go before the end of winter, Columbia has recorded 2.7 inches of snow. That's 8.3 inches shy of the normal snowfall of 11 inches for this point in the winter, Sipprell said.
Pat Guinan, an extension climatologist with MU's commercial agriculture program, said the least amount of snowfall in Columbia since 1900 was 3.5 inches during the 2005-06 winter season. The average yearly snowfall recorded since 1900 is about 20.8 inches, more than seven times the 2.7 inches this winter.
December saw most of this year's snow at the Columbia Regional Airport, which serves as a National Weather Service station. Columbia received 1.9 inches in December; the most snow was 1.1 inches on Dec. 16.