The heat in my apartment is broken. When my partner and I noticed this last month, we figured we could put off dealing with it.
“It’s almost summer! Baltimore’s warm in May,” I said. “We don’t need to worry about heat.”
Oops. It might snow in a couple days.
The polar vortex isn’t just for winter. Normally bottled up in the Arctic, our friend is forecast to bring frosty conditions from the Rockies eastward this weekend. It could bring snow to the Northeast and mid-Atlantic, and record-challenging low temperatures to the upper Midwest and New England as well.
The National Weather Service has issued freeze watches and warnings across an area from South Dakota to North Carolina. But the cold will intensify further on Friday when areas from Chicago to parts of Pennsylvania and New York could experience record-low temperatures.
On Saturday, temperatures in cities such as Pittsburgh, Detroit, Buffalo, and are predicted to see record cold, too. Washington D.C. temperatures could dip below 52 degrees, which would set a daily low temperature record that’s stood since 1877. Over the course of the weekend, the most extreme cold is expected in the Rocky Mountains, Great Lakes, and Northeast. Temperatures could fall to as much as 20 t0 25 degrees Fahrenheit below seasonal highs, but even parts of Mississippi and Alabama could see temperatures dip to a chilly 40 degrees Fahrenheit, and frost could even be seen as far south as northern Georgia.
The main culprit for this major temperature dip is our good friend, the polar vortex. Winds race around the North Pole and usually bottle up cold air there. But every now and then, those winds break down, allowing cold air to escape. That’s what will happen over the Great Lakes, New England, and elsewhere to end the week and cause these frigid temperatures.
Warm waters in the Pacific Ocean similar to the so-called “Blob” of a few years ago are also playing a role. Woods Hole Research Center atmospheric scientist Jennifer Francis told Earther in an email that waters off the West Coast have been abnormally hot for months, “which usually tends to cause weather patterns like the one we’re expecting this weekend” with a huge dip in the jet stream allowing cold air to spill into the eastern U.S. Blob-like conditions are expected to become more common as the climate continues to warm.
While the eastern U.S. is enveloped in this chill, the West and Southwest will see a heat wave. There’s also a growing body of research that shows global warming actually is directly related to the chilly spells caused by the polar vortex. Melting sea ice in the Arctic may be linked to changes in the polar vortex, though it’s very much an active area of research. The basic idea is that open ocean absorbs more heat than reflective ice, causing a hotspot. That hotspot, combined with climate crisis-driven changes in the powerful winds that steer weather systems in the Northern Hemisphere known as the jet stream, can drive the polar vortex winds haywire and unleash cold on the mid-latitudes.
This has happened in multiple recent winters, though thankfully not the most recent one. If this continues, we could see more freakishly cold snaps in future years as the climate crisis progresses—especially if we don’t curb our greenhouse gas emissions.
Anyways yeah, about my heat. I should probably get that fixed.
Update, Thursday, May 7 5:00 p.m.: Jennifer Francis’ comments have been added to this post.