Columbia avoided the worst of early January’s polar vortex, but December temperatures were, on average, colder than last year.

According to the National Weather Service statistics, Columbia’s average monthly temperature for December 2013 was 29.9 degrees — roughly 10 degrees colder than the previous December’s average temperature of 39 degrees and slightly colder than the mean of 33.3 degrees, which takes into account 124 years of weather data.

Additionally, the seasonal snowfall averaged 33.7 inches for 2013, which is more than triple 2012’s snowfall. This average ranks 13th in Columbia’s list of snowiest years, taking into account snowfalls from as far back as 1891.

As a result of a cold air mass called the Siberian Express, December temperatures in Columbia dipped to one degree while winds picked up to 25 mph. The Siberian Express air, combined with snowy conditions, led to January’s polar vortex winter storm.

“Meteorologists just started calling it (the polar vortex) this year,” said Ben Miller, a meteorologist at the National Weather Service in St. Louis.

Miller said the Siberian Express happens every year in Alaska and Canada but normally doesn’t reach the middle of the country.

“Every so often an amoeban arm of (the polar vortex) will dip down across the globe, and it’s truly polar (air) and runs right over snow,” Miller said. “The magnitude of the pattern doesn’t happen that often.”

Temperatures dipped to 14 degrees Tuesday night, a sharp drop from Monday afternoon temperatures around 50 degrees. This temperature plummet, however, doesn’t signify a second polar vortex, Miller said.

“We only look out to seven days, and there’s nothing close to (the vortex) happening for the next seven to 10 days,” Miller said. “Those kind of outbreaks don’t happen often.”

While the mixture of snow and colder-than-average temperatures brought attention to past records, it also caused problems for the present road conditions during the storm.

Columbia Public Works Department spokesman Steven Sapp said in an email that the blowing and drifting snow, along with the bitterly cold temperatures, posed a few problems for plowing crews trying to clear streets.

“Because it takes us 12 to 15 hours to plow and treat priority routes to a passable condition, traffic on residential streets was being packed down by traffic,” Sapp said. “When we did get into residential areas, salt was not effective and our plow blades would only take off the top layer of a couple of inches of snow, leaving hard packed snow and ice on the roads.”

Because of the continuing snowstorm and the time it takes to clear streets, Sapp said some people thought it didn’t appear that the streets were even being cleared.

“Our goal during any winter weather event is to make roads passable,” Sapp said. “A part of that goal is to communicate with our customers what our current and expected actions will be.”

To keep residents informed about current road conditions, the Public Works Department created a Web page, [comosnow.com](http://www.gocolumbiamo.com/PublicWorks/Streets/Snow/index.php).

Sapp said the new page makes it easier for people to refer to current department priorities and policies, and it also allows people to look at priority routes and progress maps of the plow crews.

The department hopes to create a mobile app for future use.