Where lightning struck the least in 2022, and why that was worrisome | will it snow in florida


Low lightning activity in the Midwest signaled a drought. Meanwhile, Florida saw its most lightning in years.


Change in lightning strikes in

2022 vs. 2015-21

Note: Map shows 2022 data compared to the

strike density average for 2015-21. Comparable

data for Alaska and Hawaii is not available.

Change in lightning strikes

in 2022 vs. 2015-2021

Note: Map shows 2022 data compared

to the stroke density average for 2015-2021.

Comparable data for Alaska and Hawaii is not available.

Change in lightning strikes in 2022 vs. 2015-21

Note: Map shows 2022 data compared

to the strike density average for 2015-2021.

Comparable data for Alaska and Hawaii is not available.

Change in lightning strikes in 2022 vs. 2015-21

Note: Map shows 2022 data compared to the strike density average

for 2015-21. Comparable data for Alaska and Hawaii is not available.

Comment

It’s not where lightning did strike last year that concerned scientists — it’s where it didn’t.

Recently released lightning data by weather and environment monitoring company Vaisala Xweather showed portions of the Midwest and Texas — typical lightning hot spots — had a weaker display of activity in 2022 compared to its recent average. The lack of lightning was a signal itself of atypical weather across the country last year, including major drought across the Mississippi River basin.

“It was a decently active year for lightning, but the distribution of it was a little bit different than we normally see,” lightning researcher Elizabeth DiGangi said.

Lightning detection is like measuring a person’s reflexes: the system can appear normal overall, but certain areas may show more signs of struggle than others. That’s what happened in 2022. After back-to-back years of concerning low activity in 2021 and 2020, the total number of lightning strikes was closer to average. Still, pockets of the country showed record low or high activity in ways that left researchers surprised.

Some places, such as the Plains, had low activity. Other locations had a ton of lightning: Data showed that Hurricane Ian and a bustling wet season supercharged the state of Florida. A fatal snowstorm in Buffalo also brought an unusually high amount of lightning in just a few days. And in the parched Southwest, an active monsoon season also brought bouts of lightning and rain — all showing ways that extreme weather can show up in a map of lightning.

Scientists say tracking lightning can also be critical to fully understand changes in Earth’s climate. The extreme weather phenomenon is an indirect measurement for how strong and frequent thunderstorms are.

“2022 is still a little bit below normal, but it’s closer to what we would consider an average lightning year,” said Chris Vagasky, a meteorologist at Vaisala, which operates the National Lightning Detection Network in the United States. “Having the lightning come back up a little bit closer to normal starts to get us maybe get some more precipitation in parts of the country where it’s needed the most.”

The number of lightning flashes sits between 20 million and 25 million flashes each year in the United States, but it’s normal for there to be fluctuations within a certain range. Each year, lightning typically fluctuates about 7 to 10 percent across the country due to normal variation in the number of thunderstorms and weather patterns, Vagasky said.

But “when you get down to smaller scales and you go down to the state level or county level … that’s when you see these really big fluctuations,” he said.

For instance, lightning in the Mississippi River basin was down 11 percent compared with the 2015-2021 average, which can be devastating as the region receives around half of its annual precipitation from thunderstorms. Less lightning can mean there was less precipitation overall in parched areas.

More concerning, this isn’t the first or second year that the region saw low activity. For the third consecutive year, large swaths of the central and southern plains experienced below-average lightning, which became apparent when water levels in the Mississippi River hit their lowest levels in at least a decade.

“Over a multiple-year period, it continues to add on itself,” Vagasky said. “If you’re not getting as many thunderstorms over that area, that’s going to exacerbate drought conditions and you’re not going to have precipitation flowing to the river.”


Number of lightning strikes, 2022

Note: Number of strikes is for each

2-by-2-km grid. Comparable data

for Alaska and Hawaii is not available.

Number of lightning strikes, 2022

Note: Number of strikes is for each 2-by-2-km grid.

Comparable data for Alaska and Hawaii is not available.

Number of lightning strikes, 2022

Note: Number of strikes is for each 2-by-2-km

grid. Comparable data for Alaska and Hawaii is

not available.

Number of lightning strikes, 2022

Note: Number of strikes is for each 2-by-2-km grid.

Comparable data for Alaska and Hawaii is not available.

Texas typically racks up some of the most lightning counts in the country. In addition to its large size, the Lone Star State receives plenty of sunlight, which causes air near the ground to become unstable and creates updrafts for thunderstorms. The surrounding water bodies can also provide ample water vapor to help feed thunderstorms.

Yet the state was suffering from a severe drought in 2022, and lightning activity was down. It still leads the country in most lightning counts this year, but the data showed a decrease of about 30 percent from just the previous year — from about 41 million lightning counts to 28 million.

What it looks like as drought strangles the mighty Mississippi

Vagasky said the lack of lightning in recent years can be attributed to an area of high pressure building over the Midwest between April and August, which prevents thunderstorms from forming. People in the central and southern plains experienced the high pressure as heat domes, which triggered intense and extensive heat waves during the summer.

DiGangi also points to the persistent La Niña pattern over the past three years. La Niña is characterized by cooler-than-normal ocean temperatures near the equator in the eastern Pacific, which can cause changes in atmospheric circulation and weather patterns near and far. DiGangi explained that La Niña tends to favor drier winters in the central United States, which further set up for dry conditions and can affect lightning during the summer.

“There’s this interesting feedback with multiple La Niña years in a row. Having these drier winters there probably contributed to the drought state in Texas,” said DiGangi, who works at AEM/Earth Networks, which also has lightning sensors across the United States and found similar lightning trends for last year.

Early winter rains have helped water levels bounce back somewhat, but more than half of the central United States and Texas are still experiencing some level of drought as of Jan. 17.

Trailing behind Texas, Florida received the second most lightning counts and highest number of events per square kilometer. The Sunshine State typically sees a lot of lightning each year due to its geography and climate, but last year’s activity was high in the state — even by Florida standards.

“This might be the most lightning that we’ve detected across the state of Florida” in nearly four decades of records, Vagasky said.

Lightning in Florida was up 33 percent compared with the 2015-2021 average, according to Vaisala data. Several counties took the top spot for most lightning in the United States. Florida and Texas were within 10 million total lightning events of each other — surprisingly close considering Texas is five times larger.

The most notable lightning event in Florida was tied to Hurricane Ian, which caused an estimated $60 billion in property damages in the state. Ian produced substantial lightning around its eyewall, where the most intense winds and rainfall in a hurricane are located. At its peak, Vaisala data showed lightning occurred every three seconds in the hurricane’s eyewall.

“Most hurricanes don’t produce a ton of lightning except when they’re rapidly intensifying,” DiGangi said. “But Hurricane Ian underwent multiple phases of rapid intensification in quick succession, so there ended up being like almost continual lightning in the core of Ian for like two days.”

DiGangi said how often storms undergo eyewall replacement and rapid intensification can be boosted by climate change, which could favor more lightning in the eyewall in future storms.

Yet Ian doesn’t explain the majority of Florida’s increased lightning activity. Keily Delerme, a meteorologist at the National Weather Service office in the Tampa Bay area, said much of the storm activity occurs during the summer.

“It’s just our wet season, so a lot of the grounds are saturated and that happens every summer,” Delerme said.

Even so, data indicated that Florida received a relatively high number of storms during last summer. At AEM/Earth Networks, DiGangi tracks “thunder hours,” or an hour when thunder can be heard in a location. The measurement is useful in highlighting places that experience storms, which may not produce a lot of lightning. Florida eclipsed Texas in the number of thunder hours in 2022, signaling a stormy year.

Lightning activity last year was also up in Arizona by 65 percent compared to the recent average, according to Vaisala data. Chalk that up to an active monsoon in the Southwest, which probably helped mitigate the fire risk, DiGangi said. The monsoon was active for a second year in a row and helped somewhat shrink drought conditions, although most of the western United States still experienced severe drought.

How climate change is rapidly fueling super hurricanes

Then there was the lake-effect storm in the Northeast, which dropped more than six feet of snow around western and northern New York and killed more than 40 people. A fatal snowstorm in Buffalo also brought an unusually high amount of lightning in just a few days. Vaisala lightning sensors detected more than 1,000 lightning events over three and a half days.

“I’m struggling to think of a time when I’ve seen as much lightning in a lake effect snow event,” Vagasky said. “Almost all of the lightning was associated with wind turbines that were on the coasts of the lakes.”

While lightning activity has been increasing over the past three years, Vagasky said climate change doesn’t appear to be affecting the total number in the country yet. Research shows that for each degree Celsius increase, the number of lightning strikes in the United States is projected to increase by 12 percent.

As the climate continues to warm, he said they will continue to monitor “changes in the amount of lightning that’s happening, where is it occurring or if it’s occurring in different places.”



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