March 2022 produced most tornadoes on record for month

WEATHER NEWS: March 2022 produced most tornadoes on record for month


With at least 210 confirmed tornadoes, 2022 produced the most March twisters on record. It surpasses a previous record of 192 in March 2017. Numbers may yet climb as surveys are completed.

Bolstered by three main events — one in early March, and two to end the month — the episodes were intense, especially for so early in the year. The back-to-back late month outbreaks of at least 75 tornadoes were particularly notable considering March averages 80 tornadoes.

The March tally of 200-plus twisters is comparable to expected numbers in April and June, which are typically far busier tornado months.

This record, however, may not be as significant as it sounds because radar technology in the past 15 years has made it easier to detect tornadoes, potentially inflating counts. Nevertheless, the swarms of twisters and related losses to life and property reveal an increasing vulnerability to these storms, particularly in the southern United States.

Two key ingredients came together to boost the month’s tornado activity. The first is instability, generated by high temperatures and abundant humidity, while the second is wind shear, or a change in wind speed and direction with altitude, which can give thunderstorms the spin required to organize and rotate.

This March, a persistent pattern favorable for an overlap of instability and shear sparked several rounds of tornadic thunderstorms.

There was a tendency for low pressure to develop over the central United States repeatedly. This persistent pattern helped push a cold and powerful jet stream, along which storms track further south than normal.

The configuration of the jet stream, in concert with high pressure near the East Coast, lifted warm and moist air north from the Gulf of Mexico. Meanwhile, the unusually far-south jet stream delivered atmospheric wave after atmospheric wave into an air mass primed for storm development.

While most of March’s tornadic activity ended up raking the Southeast, the first major event impacted the Upper Midwest. An intense blast of jet stream winds crashed into a narrow tongue of warm, unstable air over south-central Iowa on March 5, leading to the development of a handful of rotating thunderstorms called supercells.

One particularly well-organized supercell spawned an intense tornado just south of Des Moines, which tracked nearly 70 miles through central Iowa. The tornado, packing peak winds of an EF-4 intensity on the 0-to-5 twister damage scale, had both the highest rating and the longest path of any tornado so early in the year to strike at such a high latitude.

Tragically, the record-breaking tornado killed six as it ripped across southern sections of Winterset, a town on the fringes of the Des Moines metro area.

Another round of intense tornadic activity slammed eastern Texas on March 21, as supercells impacted the sprawling metro area of Dallas-Fort Worth, Austin and San Antonio.

One particularly noteworthy tornado devastated portions of Jacksboro, Tex., causing significant damage to the local high school; it was rated an EF-3. Another strong tornado that evening was responsible for a fatality in Grayson County, north of Dallas. A twister in Elgin, near Austin, was captured flipping a truck that then drives away, seemingly unscathed in a video that went viral on Twitter.

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The Texas supercells evolved into a powerful and broken line of thunderstorms called a QLCS (or quasi-linear convective system) into the 22nd, which would go on to produce widespread damaging wind gusts and dozens of tornadoes across the Southeast. Along the southern edge of the storms, an intense EF-3 twister ripped through the east side of New Orleans, devastating the community of Arabi. One person was killed in what ended up the strongest tornado on record for the city.

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Yet another round of powerful severe thunderstorms popped up late March 29 before ripping across the Mid-South on the 30th. A powerful EF-3 tornado struck the city of Springdale, Ark., resulting in significant predawn damage to an elementary school and sending seven people to the hospital.

A number of other strong tornadoes caused damage to towns and small cities across the southeast on March 30 as a QLCS ripped across the region. Evening tornadoes caused significant damage in McLain and Toomsuba in Mississippi, and a number of powerful late-night supercells impacted areas surrounding Birmingham and Mobile.

Early on March 31, a tornado killed two near Chipley, a town in the Florida Panhandle. Two tornadoes hit Northern Virginia that evening, in addition to several touchdowns in Pennsylvania.

As of Tuesday, this event produced 78 confirmed tornadoes compared with 77 in the previous event.

QLCS tornadoes, because they are often weak, short-lived and wrapped in rain, have historically been notoriously difficult to detect. As a result, many have been missed.

Upgrades to Doppler radar in the past 15 years have unlocked many mysteries and have aided in identifying these twisters. A technology known as dual polarization allows radar watchers to confirm many touchdowns as they happen. This leaves some question as to whether we are seeing a major increase in tornadoes or if scientists are still finding more tornadoes than they would have in the past.

“We are detecting these type [of] events far better than ever before,” Walker Ashley, an atmospheric scientist and disaster geographer at Northern Illinois University, wrote in an email.

The month’s 210 tornadoes include 176 weak (EF-0 or EF-1) tornadoes. A linear trend of these type of tornadoes in March, as in many months, has been significantly upward.

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While a high number, the 34 strong tornadoes, rated EF-2 or higher, ranked seventh highest for March and were in the general company of recent years such as 2012, 2006 and 2007. Certainly not unprecedented.

“The upgrades to the NEXRAD system are permitting us to build a more robust climatology, but this also affects the trends. Just because we have a ‘record number of tornadoes’ during a chosen period, doesn’t mean it’s a true record — it’s a record for observed tornadoes,” Ashley wrote.

Climate change and development trends increasing early season tornado risks

How much the episodes of severe weather in March were influenced by climate change is presently unknown. Other than the devastating long-track EF-4 in Iowa on March 5, the tornado events during the month were generally in their climatologically favored zones or where they’re generally expected.

There is also often a significant ramp-up heading into April when it comes to severe weather. April through June are peak season. Damaging tornado events in the South during early spring have been common throughout history.

But the elevated March tornado activity this year may be a sign of what’s to come, especially across the South.

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Studies analyzing tornado trends have found spring numbers increasing in the South while decreasing in the Plains. At the same time, the South is becoming more vulnerable to twisters because of population and development trends. There is an increase in sprawl as well as vulnerable housing (mobile and manufactured homes). Ashley refers to this as an “expanding bull’s eye effect.”

If early season tornado activity increases in the South as vulnerability grows due to demographic trends, disaster can more readily happen.

“One thing I am certain of is that societal exposure has continued to increase and expand, putting more and more people in harm’s way when these events do occur,” Ashley wrote.

While March produced fatal tornadoes, Ashley stresses the situation could have been much worse.

“At the end of the day, it only takes one, long-track violent tornado to surpass the consequences of dozens, if not a hundred, weak tornadoes,” Ashley wrote. “What matters to society is tornado footprint and its intensity, NOT counts. … I’d argue we were VERY lucky, especially on March 5th, when a violent tornado nearly missed the core of a major metro area: Des Moines.”



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