As the South reels from more than 30 tornadoes reported across the region last week, new climate data shows that the destructive storms may be on the rise.
A string of damaging and deadly tornadoes landed in multiple states including Alabama, with six deaths recorded in the state’s Autauga County, officials said. A 5-year-old boy died in Georgia when a tree fell on a vehicle, killing him inside.
The devastation comes as scientists continue to study the effects of climate change on the production of tornadoes, and almost a year after the U.S. saw a record-breaking month of tornado activity, with over 200 storms.
More strong wind activity is forecast for this week. The National Weather Service (NWS) issued tornado advisories on Wednesday for parts of eastern Texas, Louisiana, Arkansas and western Mississippi. All are expected to get strong winds.
Rare tornado emergency issued in Alabama
Wednesday’s advisory comes less than a week after the storms that ravaged Alabama and Georgia. When the storm hit Alabama, Gov. Kay Ivey declared a state of emergency for six counties in the state. Tornado watches were also issued in parts of Alabama, Florida, Georgia, Mississippi, North Carolina, South Carolina and Tennessee.
Tornado emergency alerts are rare and only issued when a life-threatening tornado has already formed with potential to cause catastrophic damage. A tornado warning is more common and is issued when a tornado is expected.
The winter season is typically considered less active for tornadoes than the spring and early summer, but forecasters with the National Oceanic and Atmospheric Administration warn that it’s important to pay attention to storm activity year-round.
“We've seen very active winters the past two years,” Bill Bunting, chief of forecast operations for the National Oceanic and Atmospheric Administration (NOAA) and the NWS, told Yahoo News on Thursday. “In fact, we're seeing tornadoes occurring even as we speak and so don't pay attention to the calendar, listen to the forecast and when those conditions come together, be prepared to take action.”
Dr. Jana Houser, an atmospheric scientist and Ohio State University professor, recently studied whether tornadoes form from clouds down to the ground or if they begin on the ground and grow up.
“Tornado outbreaks are relatively small-scale events and as such, they are very sensitive to a number of atmospheric variables, which need to all come together at the right place and in the right time,” Houser told Yahoo News.
Tornado activity in U.S. may be on the rise
New data published on Jan. 10 shows there were potentially more tornadoes spawned in 2022 than in the previous two years, with the NOAA showing a preliminary number of 1,331 last year — “about 9% above the 1991-2020 annual average across the contiguous U.S.” If that number were to stay the same or rise, it would be more than the final count in 2021 and 2020, according to the NOAA report “Assessing the U.S. Climate in 2022.”
“March had triple the average number of tornadoes reported (293) and the most tornadoes reported for any March in the 1950-2022 record,” the report states.
NOAA makes it clear that comparisons should not be made between preliminary and final counts.
“It typically takes several weeks, sometimes even a couple of months after an event, a tornado or damaging thunderstorm winds, to get a full sense of the impact [and] to get information from local officials, do surveys and then integrate that into a report that can be used to compare one year to another,” Bunting said.
Prior to 2022, there was a three-year tornado count average of 1,304. In 2019, there were 1,517 tornadoes, followed by 1,082 in 2020 and 1,314 in 2021, the NOAA data shows.
While March broke records with the number of tornadoes, the strongest twister of the year occurred in April in a city outside of Savannah, Ga., and ranked as an EF-4 on the Enhanced Fujita Scale, with estimated winds around 185 mph. An EF-4 is anything between 166 mph and 200 mph and is described as having the potential to cause devastating damage.
The storm first formed in Texas during a multi-day severe weather event that made its way to the East Coast. The outbreak produced at least 89 tornadoes, including a tornado that tore through Pembroke, Ga., killing one person.
In 2021, tornadoes were responsible for the most injuries (not including fatalities) made to people compared to other weather events, according to the National Safety Council.
Tornadoes are difficult to detect early, but new technology could help
Tornadoes are harder to predict than other devastating events, like hurricanes, experts told Yahoo News.
“There is work being done to provide seasonal forecasts for tornadoes and present those forecasts — they show promise, but they’re not really quite ready to be shared broadly,” Bunting said.
He added, “There are some predictors that can be used to anticipate whether or not it's likely to be a more active season. The state of El Niño or La Niña sometimes has some predictive skill, but in many cases, it doesn't and when you think about tornadoes, they are very small-scale phenomena. The thunderstorm that would produce it might be five or 10 miles in diameter.”
Houser said experts are gaining a better understanding of how climate change might affect these phenomena.
“The general trends of a warming climate actually imply a reduction in the number of days during any given year that the conditions will be favorable for tornadoes,” Houser told Yahoo News. “However, there is some evidence [suggesting that] while the total number of days during the year over which tornadoes form may decrease, the conditions on days that are supportive of tornado production
s storms may be favorable on a larger geographic scale and those conditions might be more volatile.”
“That is to say, on days that produce tornadoes, outbreaks might be more spatially expansive and the tornadoes could be stronger.”
Some scientists say that the conditions that create tornadoes are becoming more common due to rising temperatures.
“All tornadoes come from thunderstorms,” Daniel Swain, a UCLA climate scientist, told Yahoo News in December 2021. Thunderstorms are made more likely and, on average, more severe by warmer weather, which causes more water to evaporate.
“With each degree of warming, or even every half degree of warming — it’s surprisingly striking even for relatively small amounts of warming — the thermodynamic environment becomes more favorable for tornadoes,” Swain said.
“The most robust increases in these tornado-producing environments seem most likely to happen in what used to be cooler times of the year,” Swain said. “In winter, historically, you didn’t have a lot of heat and humidity. So what seems to be happening, the most plausible connection to climate change, is that in these cooler season months, you have a lot of warming and additional moisture in the atmosphere.”
Bunting recommends that people monitor forecasts and pay more attention to the details. This is particularly important for people living in Tornado Alley — an area of the central U.S. where twisters are most frequent — but is also important for those living in other areas of the country as well. Experts say it’s critical to have a plan in place for if a storm approaches and have a weather radio or phone app that could help.