The number of tornadoes has been decliningfor the past 45 years.
The number of strong tornadoes, F3 or higher, has been dramatically decliningfor the past 45 years.
In 2017-2018, the U.S. set a record for the longest period in history without a tornado death.
In 2017-2018, the U.S. set a record for the longest period in history without an F3 or stronger tornado.
Thetwo record-low years for number of tornadoes both occurred this past decade – 2014 and 2018.
According to a reports by the United Nations, “There is low confidence in observed trends in small spatial-scale phenomena such as tornadoes.”
Short Summary:
Tornadoes typically form when very cold, dry air clashes with warm, humid air. Climate change warms the Arctic more than the tropics and subtropics, resulting in less of a clash between cold Arctic air masses and warm Gulf of Mexico air masses. As a result, fewer and less violent tornadoes are occurring today than in previous periods, despite media claims that tornadoes are getting more frequent, stronger, or both.1,2
The number of tornadoes in the United States, as well as in other countries, has been slowly declining for the past 45 years. At the same time, the number of strong to violent tornadoes, EF3 or higher, has been dramatically declining for the past 45 years. (See Figure 1.) In fact, the United States set a record in 2017–18 for the longest period in recorded history without a tornado death, and it set a record for the longest period in history (306 days) without an EF3 or stronger tornado.3,4 The two record-low years for tornado strikes in the United States both occurred this past decade, in 2014 and 2018.5
Further, even the U.N. Intergovernmental Panel on Climate Change has acknowledged, “There is low confidence in observed trends in small spatial-scale phenomena such as tornadoes.”6
Figure 1. U.S. Annual Count of Strong to Violent Tornadoes (EF3+), 1970–2020
Figure 1. This figure shows the frequency of strong to violent tornadoes (tornadoes registering EF3 or stronger) has been declining since the early 1970s. Sources: Graph by Anthony Watts using official NOAA/Storm Prediction Center data.7,8,9
Graph data from National Oceanic and Atmospheric Administration’s National Weather Service, Storm Prediction Center website, accessed August 16, 2021, https://www.spc.noaa.gov/wcm
The number of tornadoes has been decliningfor the past 45 years.
The number of strong tornadoes, F3 or higher, has been dramatically decliningfor the past 45 years.
In 2017-2018, the U.S. set a record for the longest period in history without a tornado death.
In 2017-2018, the U.S. set a record for the longest period in history without an F3 or stronger tornado.
Thetwo record-low years for number of tornadoes both occurred this past decade – 2014 and 2018.
According to a reports by the United Nations, “There is low confidence in observed trends in small spatial-scale phenomena such as tornadoes.”
Short Summary:
Tornadoes typically form when very cold, dry air clashes with warm, humid air. Climate change warms the Arctic more than the tropics and subtropics, resulting in less of a clash between cold Arctic air masses and warm Gulf of Mexico air masses. As a result, fewer and less violent tornadoes are occurring today than in previous periods, despite media claims that tornadoes are getting more frequent, stronger, or both.1,2
The number of tornadoes in the United States, as well as in other countries, has been slowly declining for the past 45 years. At the same time, the number of strong to violent tornadoes, EF3 or higher, has been dramatically declining for the past 45 years. (See Figure 1.) In fact, the United States set a record in 2017–18 for the longest period in recorded history without a tornado death, and it set a record for the longest period in history (306 days) without an EF3 or stronger tornado.3,4 The two record-low years for tornado strikes in the United States both occurred this past decade, in 2014 and 2018.5
Further, even the U.N. Intergovernmental Panel on Climate Change has acknowledged, “There is low confidence in observed trends in small spatial-scale phenomena such as tornadoes.”6
Figure 1. U.S. Annual Count of Strong to Violent Tornadoes (EF3+), 1970–2020
Figure 1. This figure shows the frequency of strong to violent tornadoes (tornadoes registering EF3 or stronger) has been declining since the early 1970s. Sources: Graph by Anthony Watts using official NOAA/Storm Prediction Center data.7,8,9
Graph data from National Oceanic and Atmospheric Administration’s National Weather Service, Storm Prediction Center website, accessed August 16, 2021, https://www.spc.noaa.gov/wcm
