Reporting Jason DeRusha
MINNEAPOLIS (WCCO) — It’s March 6th and we’re dodging puddles. People dropped their coats, put on flip-flops and shorts, and enjoyed a high temperature near 60.
So, does the lack of snow cover lead to a warmer spring?
“The snow itself can have a major impact,” said WCCO Chief Meteorologist Chris Shaffer. “Fancy word: albedo. That is the reflectivity of the surface.”
When we have lots of snow on the ground, sunlight reflects back into the atmosphere. Plus, the sun’s energy is wasted trying to melt the large pile of snow.
However, when the ground is relatively bare, “all of that sunlight can absorb into the ground and kick back as heat,” said Shaffer.
In Minnesota on March 6, the Twin Cities had a high of 57. As you look north and see more snow covering the ground, the high temperature was in the 40s.
The warming effect of the lack of snow isn’t just for one day, however. According to Shaffer, the lack of snow on the ground leads directly to warmer weather at the start of spring.
“Odd use of the term snowball effect – the more snow we melt away now, the better chances we have of warming into the 50s this weekend,” he said, and the better chance we have of staying warm through March and April.
For example, Shaffer sees precipitation from a major storm headed our way for St. Patrick’s Day.
“If we had snow, and air temps were cooler, that could be a ‘tournament snow.’ Instead it looks like we’ll get a big soaking of rain,” he said.