GREENVILLE, N.C. (WNCT) — I’m sure you know about the winter storms that battered North America this February, leading to record-breaking snow cover in the United States.
How did this even happen? It all revolves around the polar vortexes, an area of low pressure that spins around the poles in both the Northern and Southern Hemispheres. It’s the stratospheric polar vortex that caused this storm, in the layer of the atmosphere just above the layer where we live.
In the weeks leading up to 2021, scientists noticed that this polar vortex was breaking down. This means the winds blowing around the North Pole were slowing and allowing temperatures to warm up. By Jan. 5, winds actually switched directions and temperatures peaked, which caused the arctic jet stream to slow and wobble.
The jet stream is what keeps the Arctic cold in the Arctic. When it slows, it allows polar air to spill into North America.
These events are not unusual, occurring about six times every decade. But, winds usually just slow down, not always reversing direction like they did this time, which allowed even more freezing air to push further south.
This is exactly what happened in February. It took a few weeks for the cold air to push south, but when it did, the arctic chill extended all the way to Mexico, bringing record-breaking cold temperatures and snow that lasted over a week.
We are very lucky that Eastern North Carolina didn’t get much of the snow, and just a little bit of the cold. Let’s look forward to a beautiful spring ahead.