Why Is U.S. Weather So Crazy Right Now?

February 21, 2018

Temperatures hit 82 degrees in Washington, D.C., Wednesday, one of the highest readings the city has ever experienced in February. And for the second day in a row, Boston set a high-temperature record for a February day: 71 degrees.

In New York’s Central Park, the temperature hit 78 degrees, the highest ever recorded in February. The milestone shattered the record for Feb. 21, which had previously stood at 68 degrees, back in 1930.

“We’re not breaking daily records, we’re breaking all-time temperature records,” said Andrew Freedman, senior science editor of Mashable.

According to Freedman, part of the explanation lies in an unusual disturbance of the polar vortex, which in the past week has split in two, producing two distinct cold waves across the globe.

“You had one portion of it moving into the Western U.S. and Canada, while at the same time one portion of it moved into Europe and Eurasia,” Freedman said. “So those are the two cold spots in the Northern Hemisphere right now. And in the eastern U.S., suddenly we had this incredible warm-up today and on Tuesday.”

Freedman explained the split in the polar vortex. “Normally, you have this circulation of fast winds in the upper levels of the atmosphere over the Arctic. Usually, it stays put; it behaves well.” But this year the planet experienced what Freedman called a Sudden Stratospheric Warming event. “You had energy from the lower atmosphere go up to the upper atmosphere and sort of knocked it off balance.”

Freedman added that climate change is also contributing to the record temperatures on the East Coast. “It’s easier for us to set these high-temperature records as the climate continues to warm,” he said. “That's the bottom line climate message overall.”

And as for what’s ahead, well, Freedman said, on Thursday, “It’s going to snow in Boston.”

Read more at Mashable.