According to NOAA’s National Centers for Environmental Information (NCEI) and Storm Prediction Center (SPC), the contiguous U.S. recorded 1,559 preliminary tornadoes in 2025. This was 127% of the 1991–2020 annual average (~1,225 tornadoes) and ranked as the fifth-highest annual total on record (behind 2004, 2024, 2008, and 2011). Some tallies list slight variations (e.g., ~1,429–1,591) due to preliminary vs. confirmed counts, but the year was clearly above average.

Activity concentrated in the southern Plains, central Gulf Coast states, and Mid-Mississippi/Ohio valleys, with notable outbreaks from March through June. March set a record with ~300 tornadoes. November was the quietest month. North Dakota shattered its state record with 72 (or up to 82 in final tallies) tornadoes.

Strong/violent tornadoes: The year included the first EF5 since 2013—the Enderlin, North Dakota tornado on June 20 (upgraded in October 2025 after detailed surveys showing winds >210 mph, with extreme damage indicators like derailed loaded train cars and swept foundations). There were also multiple EF4s (at least five confirmed), including events in Arkansas, Louisiana, Illinois, and Kentucky during March and May outbreaks.

Fatalities: Approximately 67–68 direct deaths in the U.S. (higher than 2024’s 54 but well below 2011’s 553). Major contributors included the March 14–16 outbreak (multiple fatalities across states) and the May 16 outbreak (dozens of deaths, notably in Kentucky). Many fatalities occurred in mobile/manufactured homes. Worldwide, tornado fatalities totaled ~105.

Damage: Preliminary U.S. property damage estimates were at least $1.9 billion, with specific outbreaks contributing significantly (e.g., March 14–16: ~$11 billion in one billion-dollar disaster analysis; May 14–16: ~$6.3 billion). These fit within recent-year ranges rather than historical extremes when considering broader severe weather context. Billion-dollar tornado/severe storm events were part of 23 such disasters totaling ~$115 billion across all weather events in 2025.

Early 2026 (through mid-April) showed near- to above-average activity in some regions, with outbreaks like April 17 in the Upper Midwest, but full-year data is pending.

Reported tornado counts have risen since the mid-20th century, driven primarily by improved detection of weak (EF0–EF1) events via Doppler radar, storm spotters, and media. In contrast, strong/violent tornadoes (F/EF3+) show no increase—and a clear decline in consistent-quality data periods:

• The 1975–1984 decade averaged ~49 F/EF3+ tornadoes per year.
• The 2015–2024 decade averaged ~26 per year — a roughly 46% decline.

Overall tornado frequency remains dominated by natural variability (e.g., seasonal patterns, La Niña/El Niño influences) rather than any detectable long-term climatic uptrend in intensity or count of significant events.

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Tornado Damage and Frequency: An Update Through 2025

The Honest Broker

Tornado Damage and Frequency: An Update Through 2025

Roger Pielke Jr.

No upward trends in normalized tornado losses or in major tornado incidence

Through yesterday, according to preliminary data from the National Oceanic and Atmospheric Administration (NOAA) Storm Prediction Center (SPC), the U.S. has experienced 365 tornadoes, just four above the longer-term average to date. Last year, more than 1,900 tornadoes were observed, the most since 2011, and well above the longer-term average.

Today, I share the latest data on normalized U.S. tornado losses since 1954 and a time series of the incidence of the strongest tornadoes since 1975. I doubt you’ll come across these data anywhere else.

Comparing tornado losses across decades is not straightforward. A tornado striking what was a rural county 70 years ago would cause far less damage than the same tornado striking that same heavily developed county today — because there is now more property and wealth exposed to loss.

To make meaningful historical comparisons of loss estimates, researchers “normalize” losses: they ask what each historical storm or event would cost if it occurred under today’s societal conditions, adjusting for factors such as inflation, wealth, building types and counts, population, and, in some cases, efforts to improve building quality.

This approach was first applied systematically to tornadoes by Simmons, Sutter & Pielke Jr. (2013), which analyzed NOAA SPC data from 1950 through 2011. Zhang et al. (2023) reproduced and extended the Simmons series through 2018, confirming the earlier results and updating the time series. They concluded: “[O]ur results suggest a downward trend in tornado losses for the U.S. as a nation.”

The figure below shows my replication of the Zhang et al. tornado normalization from primary data and extends it through 2025. The normalized losses are expressed in 2026 dollars.

The dominant loss years are 1954 ($36 billion),1965 ($44 billion), and 1974 ($29 billion). The largest recent loss year is 2011 at $16 billion — the largest post-1980 value and the only recent year approaching the scale of the 1960s–1970s peaks. Since 2012, annual normalized losses have largely remained below $5 billion.

The time series shows a significant decrease in annual normalized losses.The 1954–1963 decade averaged $4.8 billion per year; the 2015–2025 decade averaged $1.9 billion per year.

Our 2013 paper identified this trend:

“We can definitively state that there is no evidence of increasing normalized tornado damage or incidence on climatic time scales.”

At the time, we hypothesized that underlying the decrease may be an actual reduction in severe tornado incidence. However, because economic data should not be used to infer trends in related climate variables, we suggested that any such trend in tornadoes would depend upon analyses of climate data.

More than a decade later, tornado data is strongly suggestive of an overall decline in the incidence of the strongest tornadoes. The figure below shows the annual count of F3/EF3 and stronger tornadoes from 1975 through 2024, the period over which data quality is most consistent.

The time series shows a clear decrease in major tornado incidence. The 1975–1984 decade averaged 49 F/EF3+ tornadoes per year; the 2015–2024 decade averaged 26 per year — a decline of roughly 46 percent. Note that data available back to 1954 makes this decrease look much larger, but is accompanied by questions of data quality.

The interpretation of this declining trend requires caution for several reasons. First, the Enhanced Fujita (EF) scale introduced in 2007 changed rating methodology, creating a potential discontinuity in the series. Most analysts believe EF ratings are somewhat more conservative than legacy F ratings for comparable damage, which could contribute to the apparent post-2007 decline. Second, improved public warnings and storm-resistant construction may have contributed to changing the nature of observable damage markers that drive intensity ratings, which are often established based on damage patterns rather than direct measurements of tornado intensity.

Neither of these caveats undermines the the fact that there is no evidence of an increase in violent tornado incidence over the observational record. The IPCC Sixth Assessment Report concluded with low confidence in the detection of any trend in tornado frequency or intensity at the global or regional level, and with low confidence in attribution of any observed changes to anthropogenic forcing. The data reviewed here are consistent with that assessment.

Several hypotheses have been offered in the literature for how accumulating greenhouse gases in the atmosphere may influence tornado behavior. Some commonly cited examples include:

• Reduced wind shear. Trapp & Hoogewind (2018) proposed that Arctic amplification could weaken lower-tropospheric wind shear, reducing the environmental favorability for supercell formation. If correct, this would represent a climate signal leading to fewer strong tornadoes.
• Geographic shift eastward. Gensini & Brooks (2018) documented a westward decline and eastward increase in tornado activity — a shift toward “Dixie Alley” and away from the traditional “Tornado Alley.” An eastern shift moves tornado tracks closer to higher-density development. They conclude: “At this point, it is unclear whether the observed trends in tornado environment and report frequency are due to natural variability or being altered by anthropogenic forcing on the climate system.”
• Increased variability. Brooks, Carbin & Marsh (2014) argued that over 1954 to 2013 tornado activity became more variable — with years of very high activity alternating with years of historically low counts — rather than showing a simple trend in frequency. They explain: “At this point, we cannot offer a physical hypothesis for the increased variability.”

The normalized loss series and the F/EF3+ incidence series both show the same pattern: no upward trend, and arguably, a significant downward trend that has contributed to lower normalized damage levels in recent decades.

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