For two weeks in February, metro-east residents almost forgot it was winter —and it’s no wonder, with temperatures consistently in the 60s and 70s.
“This February was the warmest on record by far,” Illinois State Climatologist Jim Angel said on Monday while looking over data recorded at the Belleville SIU research farm just outside of the city.
He noted that on Feb. 20 a record high of 77 degrees was reached.
With data reaching back to 1948, Angel said, Belleville’s February average (day-round) temperature of 48 degrees far surpassed any other year on record. For perspective, he said, in 2016 the month’s average temperature was 40.5 degrees, and in 2014, it was 28.2 degrees.
“If you look at the numbers — like we have for a long, long time — a lot of the time average temperatures aren’t much different from one year to the next,” Angel said. “So that’s a pretty big jump. It’s actually pretty extraordinary.”
In that same line, the average high temperature for the month of February this year was 61.4 degrees — almost 10 degrees higher than 2016 (51.7 degrees) and more than than 20 degrees higher than 2014 (39 degrees).
Angel said a lot of locations, including Springfield and Chicago, were setting records “left and right.”
And with those abnormally warm temperatures, came abnormally low precipitation levels.
In February 2017, Belleville received 0.34 inches of precipitation compared to 0.52 inches last year. In 2014, records indicate 1.18 inches of precipitation fell in February.
Angel said these levels include water content of the snow (and rain), and he noted the rule of thumb is to think that 10 inches of snow melts down into about 1 inch of water.
So why the dry, warm days in the dead of winter?
“I think there are two parts to it,” Angel said. “One is this trend of seeing milder winters in Illinois for the last 30 years or so — that one we are pretty confident that is global warming. … On top of that, we (recently) had a very unusual high air pressure sitting on top of us. ... So all the storms were tracking to the north of us in Minnesota and Wisconsin.”
University of Illinois Professor Jeffrey Frames, who teaches in the department of atmospheric sciences, echoed those thoughts.
“There have always been warm days in the winter, there will always be warm days in the weather — but climate change is a long-term increase in global temperatures,” he said. “What I can say is that climate change does not make it 70 degrees instead of 40 degrees in the winter. ... The way to look at (climate change) is that the warm days in the winter are now 70 degrees instead of 68.”
In terms of relating last month’s temperatures to climate change, he added that scientists will need to conduct a detailed attribution study to really understand these numbers.