Overview
With Wicked: For Good coming out, we wanted to know: What kind of tornado would have to happen to transport a house (and its occupants) to Oz? The Hazard HQ Command Central team breaks down tornado classification and explains how to ensure a forthcoming tornado doesn’t take you over the rainbow.
Everyone has Wicked on the brain, and we’re no exception. However, we’ve been thinking about a minor character that plays a major role: the tornado that ultimately led to the Wicked Witch’s death.
While we don’t have the technical specifications of that tornado, its strength is reminiscent of the 2020 Nashville tornado.
According to Cotality data, there were 22,389 structures in the tornado path, with a reconstruction value of roughly $2.4 billion. These homes had a 30% or greater probability of experiencing some damage from the tornado. It’s safe to say that with a tornado like that, Dorothy’s house would likely have collapsed rather than been carried off to a new location.
Dorothy was probably unaware of how powerful the storm was that blew her into Oz. But as hazard modelers and risk experts, we are keenly aware of the importance of understanding the details of each storm event is crucial to preparing a resilient response. The good news is, you don’t need to specialize in risk management to effectively prepare for a storm. Here’s what you need to know.
Understanding tornado classification
Like the category system for hurricanes, there is a classification system for tornadoes: the Enhanced Fujita (EF) Scale, which measures intensity based on the damage caused. This classification system is a guideline for determining risk so that people — like Dorothy — can prepare for the storm and accelerate their recovery afterwards.
So, how strong would a tornado have to be to carry Dorothy and Toto to their ozmopolitan adventure?
- EF1 (Weak): Winds of 86-110 mph. This might have ripped some shingles off the roof, but Dorothy and Toto would have barely noticed. The house would stand firm.
- EF2 (Strong): Winds of 111-135 mph. Now we're talking about significant damage. An EF2 can tear the roof off a farmhouse, but it wouldn't have the power to lift the entire structure.
- EF3 (Severe): With winds up to 165 mph, an EF3 tornado can destroy entire stories of well-built homes. Dorothy would be in serious danger, but the house itself would likely be demolished, not relocated.
- EF4 (Devastating): With winds of 166-200 mph, an EF4 can level well-built homes and sweep foundations clean. While movie magic allows for a house to fly, in reality, an EF4 or rare EF5 (winds over 200 mph) would likely shred the structure entirely rather than lift it whole.
Understanding tornado classification is critical for people who live in “Tornado Alley” and other parts of the country that experience this kind of weather event regularly. If you know your risk, it makes recovery that much easier.
From touchdown to fallout
If an EF4 tornado hit Dorothy's farm in 2025, the financial impact would be devastating, according to Cotality data.
- The House: Rebuilding a modest 1,500-square-foot farmhouse today could easily cost over $250,000. And that’s just the house.
- The Farm: Add in the cost of a destroyed barn, ruined crops, and modern farm equipment (a new combine harvester can cost $500,000+), and total damages could quickly soar past $1 million.
The story of Dorothy’s tornado is fiction, but the perils that occurred are very real risks.
Thorough preparation is key, and the good news is, there are things you can do to proactively protect your home such as securing outdoor furniture, identifying a windowless safe room on the lowest level of your home, and stocking up on three days’ worth of emergency supplies, as well as helmets and sturdy shoes.
Additionally, understanding coverage specifics, including what kind of replacement cost your policy provides — Replacement Cost Value (RCV) to build a brand-new house, or only the Actual Cash Value (ACV) of the old, depreciated one — and which perils are covered are crucial to ensure you are truly protected.
Tornado Alley shifts
Historically, Tornado Alley exists over the Central Plains, ranging across states like Kansas, Oklahoma, and Texas. But these traditional boundaries are shifting. A larger number of significant tornadoes have appeared over the last few decades in Southeastern states like Alabama, Mississippi, and Louisiana, making up a region that is now called Dixie Alley.
While losses from severe convective storms have increased over the past few years, this can be attributed to urbanization in hazard-prone areas, rising asset values, and inflation (mainly due to rising construction costs).
As weather patterns have evolved, so too have the tools that help us understand them. This empowers us to take proactive action to reinforce and mitigate structures to prepare for these kinds of storms. At Cotality, we’re dedicated to helping people understand their risk, because when you know your risk, you can accelerate your recovery.
To better understand the risks various hazards present before they happen, read our risk reports:
To learn more about our risk management solutions, visit the Cotality website to learn more.
