Shocker: 194M bolts of lightning detected in the U.S. last year

If it seems like you experienced a lot more severe weather than usual last year, you aren't imagining things. The year 2021 featured a host of record-breaking storms across America. From the Heartland to the Northeast to the Desert Southwest and along the West Coast, it was a stormy year. And a new report says there was more lightning, too.

Experts at lightning research firm Vaisala, based in Finland, reported 194 million cloud-to-ground and in-cloud lightning events occurred in the continental United States last year. That's an increase of 24 million or 14 from 2020 but short of the average of 220 million, according to Vaisala meteorologist Chris Vagasky.

The year "2021 is a little bit closer to normal," he told AccuWeather national reporter Bill Wadell. "That's still about 15 to 20 million lightning events lower than what we would usually see."

Vagasky said a severe weather outbreak in spring was the biggest lightning maker of 2021.

"We had tornadoes in Colorado, Texas, the Southeast, but the bulk of the activity was on May 2, which was over 4 million events, the most we've detected since 2017."

Another surge in lightning in 2021 was from the significant severe weather outbreaks in December, a month that featured a host of anomalous weather, including a historic tornado outbreak which resulted in the deadliest storm in Kentucky history, record-breaking temperatures, and the first-ever December derecho.

AccuWeather senior weather editor Jesse Ferrell noted that "the county density data showing above-normal lightning activity in Michigan, Utah, Arizona, Pennsylvania, New Jersey and Connecticut roughly corresponds with record-high severe thunderstorm and tornado warnings and reports in 2021."

Texas, with nearly 42 million lightning strikes, was the state with the most lightning strikes in 2021, but the Lone Star State tops the charts every year due to its size and location. Florida was a distant second at 14.6 million strikes with Louisiana, Oklahoma and Missouri rounding out the top five. Taking land area out of the equation, Florida experienced the most lightning density -- strikes per square kilometer -- of any state last year, at 85.99, followed by Louisiana at 81.62.

When data was averaged out between 2016 and 2020, Oklahoma overtook Florida for the distinction as the lightning capital of the United States, but Vagasky says the Sooner State had a big drop last year and is no longer a contender.

"Last year, we were talking about: 'Is Oklahoma the lightning capital or is Florida the lightning capital?' Oklahoma didn't even hit 10 million lightning events in 2020, so that was a big decline for them," he said. While the data isn't official yet, it sounds like the Sunshine State may be taking that title back.

In the West, lightning strikes are typically lower, largely due to the cooler air blowing off the Pacific Ocean. Cooler air near the ground provides a relatively small amount of vertical temperature difference, so the air is less likely to rush upward and produce thunderclouds. Also, cooler air holds less moisture than warm air. Less moisture means less fuel to kick-start storms. As a result, Alaska ranked as the fewest lightning strikes per square mile at 0.52. Washington (0.78), Oregon (2.0), Hawaii (2.62) and California (2.67) round out the bottom five.

Ferrell said the U.S. building struck the most by lightning in 2021 was no surprise. "The Willis Tower in Chicago was the most frequently-struck skyscraper in 2021, taking on 216 strikes, while One World Trade Center was the most-struck in New York City and was hit 109 times during the year." Ferrell added, "A report AccuWeather commissioned via Vaisala in 2021 also gave the Willis Tower the No. 1 ranking for the tallest skyscrapers hit by lightning over a five-year period."

Elsewhere in the U.S., the Desert Southwest had an uptick in storms. "Arizona had a big return of the monsoon. In 2020, they had only about a million lightning events detected, but in 2021, there were three-and-a-half million," Vagasky explained. More than 2 million acres across the drought-stricken western U.S. were burned in wildfires sparked by lightning. This number includes the Bootleg Fire in Oregon that burned more than 400,000 acres in 40 days and began generating its own weather.

"What we hope to see continue is this lightning data will better help us understand the planet, help us understand the weather patterns that are going on and help keep people safe," Vagasky said.

Technology and safety awareness seem to be paying off. Although there were more lightning strikes than 2020, lightning fatalities dropped with only 11 deaths reported in 2021 -- the lowest since records began in 1940. "This new low of 11 lightning deaths is dramatically fewer than the 432 Americans killed by lightning in 1943," said John Jensenius, a lightning safety specialist with the National Lightning Safety Council.

Internationally, Brazil had more total lightning than any other place on the planet, with more than 225 million strikes in 2021. The U.S. comes in second, the Democratic Republic of Congo third, with Australia and China rounding out the top five. However, the most lightning density per square kilometer award went to Singapore.

The global trend getting the most attention is a dramatic surge of lightning in the Arctic. In the spring of 2021, a paper reported that lightning had tripled in the Arctic over the previous decade. Typically, lightning is rare in the Arctic compared to other parts of the world, in part because thunderstorms require heat, and most of the area is covered by ice and snow. Climate scientists attribute the increase to rapid warming related to climate change and an increasing loss of sea ice. Because the thunderstorms that generate bolts require heat to form, lightning strikes are one variable scientists use to track climate change.

In July 2021, scientists were stunned by episodes of summer lightning in the Arctic Circle when three thunderstorms swept from Siberia across the Arctic discharging lightning bolts across the region.

"Going from Siberia into the Arctic Ocean and developing storms there is not very common," Vagasky explained. "But in 2021, north of 80 degrees north [latitude], so this is the very high reaches of the planet, we detected almost twice as much lightning as we did between 2011 and 2020."

Vagasky says experts around the world are monitoring the changes that indicate a warming trend in one of the coldest places on Earth is happening faster than in other locations around the globe.

"Monitoring what's happening in the Arctic is going to be critically important to understanding how [the] climate is changing."