The climate crisis is behind more and more deadly tornadoes like those on Friday night

In 2019, a study from Towson University made some pretty explicit predictions about how climate change was affecting the distribution of tornadoes across the United States. Things were changing both in how tornadoes are distributed across the nation, and how they are distributed across the calendar.

Tornado activity is increasing throughout the Southeast and in the southern portion of the Midwest and is decreasing throughout the southern and northwestern portions of the Great Plains and in the northern Midwest. Days with few tornadoes are becoming less common whereas days with many tornadoes are becoming more common. The seasonality of these big tornado days also appears to be changing, as their increase in frequency is greatest in the fall and winter.

That classic Wizard of Oz tornado — striking on a summer day in the plains — is actually becoming less common. What’s becoming more common are clusters of tornadoes hitting further south and further east, and striking in seasons that used to be relatively free of such storms.

But there's more than just a shift to new areas that are making these tornadoes more deadly. These southern tornadoes are more likely to occur at night, more likely to be shrouded in rain, and are simply more difficult for people to spot before it’s too late.

In 2022, CNN put it this way, the traditional "tornado alley" stretched across Kansas and Nebraska down to central Texas, but in more recent years, more tornadoes "are appearing in the Southeast, in eastern Texas, Louisiana, Arkansas, Tennessee, Mississippi, Alabama and Georgia."

As those tornadoes move east, they’re not just becoming more deadly in part because they're entering areas of high population. Mississippi and Arkansas may have populations only slightly higher than Kansas, but Alabama and Georgia are much larger. Even states like Texas, part of both the old and new zones where tornadoes are most likely to appear, are seeing the storms move from the less populated north central areas of the state, to heavily populated areas in the east and south.

There's also a different kind of geography at work that makes these storms more difficult.

Unlike the Plains, where a tornado can be seen coming from miles away, the Southeast has more rugged terrain and more trees, making it more difficult to spot a tornado. Many tornadoes occurring in the area are "rain-wrapped," so they are less visible to the naked eye, CNN meteorologists said.

It's nice to think that everyone has their weather radio on all the time, or that every small town is covered by tornado sirens audible to everyone. But that’s not the case. Most people take caution concerning tornadoes only when severe weather is already in the area, or when predictions of coming storms have been well publicized. Tornadoes arriving at night, on the leading edge of series of squalls, are much more likely to find people waiting in bed — especially if these are rain-wrapped storms whose presence isn’t confirmed until the tornado is on the ground, carving a path through the landscape.

Many people in the area also have mistaken ideas built up over decades of folk wisdom and luck. Ideas like “tornadoes don’t hit cities,” often backed up with claims that it’s because the asphalt and buildings create a "heat bubble" that deflects tornadoes. Such ideas linger, even after the tornadoes like the one that ripped through Tulsa in 2017.

Even more common is the belief that hills and other terrain features provide protection. The presence of all those tornadoes on the plains for so long left many with an impression that plains were the only place where tornadoes represent a real threat. Forests, hills, and rivers are all cited as supposed "barriers" for tornadoes. They are not.

Compounding all this is that homes in the southeast are much less likely to have basements than they are in some areas of the country. Also, because they have not been part of the traditional "Tornado Alley," storm shelters are very uncommon.

The death toll for the storms on Friday night currently stands at 24. Most of those were in Mississippi where the town of Rolling Fork (population 1,776) was reportedly “erased” by the storm.

Tornado Destroys a 'Great Deal' of Rolling Fork, Mississippi, Former Mayor Saysyoutu.be

That 2019 study was just one of many warnings that with rising global temperatures will come more severe storms in the U.S. This is a pattern that is expected to get worse.

We're getting nighttime, rain-wrapped tornadoes that are harder to see, arriving at unexpected times of the year, in more highly populated areas, endangering people for whom such storms were previously far more rare and more constrained to summer months. That’s not an issue that’s going to be solved by improving weather radios.