Thanks to the record-breaking Arctic outbreak that stretched all the way into Texas, February was the coldest it has been across the US in over 30 years, says the National Oceanic and Atmospheric Administration. However, across the US, it was still in the top third of warmest winters on record.
“During February, the average contiguous US temperature was 30.6°F, 3.2°F below the 20th-century average,” NOAA announced Monday. “This ranked as the 19th-coldest February in the 127-year period of record and was the coldest February since 1989.”
This bone-chilling cold hasn’t been seen in February since a year before Vanilla Ice released “Ice Ice Baby.” And it was all thanks to a strongly negative Arctic Oscillation (AO), which favors cold air outbreaks across the US.
Or in terms often used to describe these outbreaks – a polar vortex.
The main driver behind the cold was the “polar vortex”, sort of
The Arctic Oscillation may have resulted from a sudden stratospheric warming event that occurred in January, said NOAA.
This warming event in the Arctic weakened the polar vortex, which normally swirls around the globe’s polar regions, allowing for arctic air to dive into extremely southern US locations, says CNN meteoroligst Allison Chinchar.
“Think of the polar vortex as the sides of a round above-ground pool. If the side breaks, all the water pours out…or in this case, all the cold air poured out,” CNN meteorologist Chad Myers says.
Records shattered like ice
“The cold snap peaked from February 14-16,” tweeted the Weather Prediction Center. “In the NCEI database, approximately 30% of available US sites set cold maximum records, and about 20% set minimum records.”
During that peak period, the analyzed temperatures were 40 to 50 degrees below average over much of the central and southern Plains.
More than 3,000 daily record cold temperatures (minimum and maximum) were reported from February 12-17 at long-term observations (75+ years of data), said the WPC.
Based on preliminary data, 62 all-time daily cold minimum temperature records were broken from February 11-16 and 69 all-time daily cold maximum temperature records occurred February 15-16, said NOAA.
“Even though the US experienced the coldest month in decades, the Earth as a whole was still slightly warmer than the average over the past 30 years,” CNN meteorologist Brandon Miller says.
“It goes to show how much humans have warmed the planet when even with such a powerful polar-vortex unleashing of arctic cold dominates the month, the Earth still manages to produce above-normal temperatures. Look no further than Europe, which was several countries set all-time record high temperatures for the month of February.”
Winter was on pace to be one of the warmest on record
And when you look at the US outside of the month of February, the winter wasn’t the coldest. In fact, it was in the warmest third.
“The winter (December-February) average contiguous US temperature was 33.6°F, 1.4°F above average, ranking in the warmest third of the winter record,” NOAA said.
The only place winter temperatures were below average was across parts of the Midwest, the lower Mississippi Valley and the southern Plains. The same area that saw the extreme abnormal temperatures in February.
Above-average temperatures were felt across much of the West, Northern Tier, Northeast and parts of the Southeast.
“Even with La Niña in place, which tends to have an overall cooling effect on the planet, the winter of 2020-21 was still on pace to be one of the warmest on record,” Miller says. “But the brutal cold snap, which was the coldest in decades for the Central US, likely kept that from occurring.”