NOAA's National Centers for Environmental Information
According to data from NOAA's Storm Prediction Center, during 2020, there were 1,053 preliminary tornado reports. This was below the 1991-2010 U.S. annual average of 1,251 tornadoes. The majority of the 2020 tornadoes occurred during April and May with another peak month in August. April produced the highest number of confirmed tornadoes (351). A majority of the April 2020 tornadoes occurred across Southern and Southeastern states from Texas to Florida to North Carolina. Nearly all of these April tornadoes occurred during four multi-day events (April 7-8, April 12-13, April 19 and April 22-23).
The first notable tornado day in 2020 was January 10, as 50 tornadoes were confirmed across Texas, Louisiana, Mississippi, Arkansas, Tennessee, and Missouri. There were an additional 32 tornadoes on January 11 that primarily impacted Mississippi, Alabama, Georgia, and Kentucky with additional isolated tornadoes in surrounding states. The January 10-11 tornadoes and associated severe weather caused substantial property damage across many states including Texas, Louisiana, Mississippi, Alabama, Georgia, Arkansas, Tennessee, Kentucky and Missouri. In addition to the widespread damage across many states, there were also 10 fatalities and numerous injuries. This was the third-largest January tornado outbreak on record.
The year's next significant tornado event was during the overnight hours of March 2-3 in which more than a dozen tornadoes tracked across central Tennessee, which led to a billion-dollar disaster. Powerful EF-3 and EF-4 tornadoes caused considerable damage across downtown Nashville and several counties and towns east of Nashville. This damage included many homes, businesses, vehicles, 90 planes and numerous buildings at the John C. Tune airport (JWN) in Nashville. This was a billion-dollar weather disaster and these tornadoes also caused 25 fatalities.
The month of April also had several tornado outbreaks. The first episode was April 7-8 where a combined 34 tornadoes affected southern Ohio, Indiana and northern Kentucky. These tornadoes caused extensive damage but no deaths. The next episode occurred on April 12-13 and produced at least 140 confirmed tornadoes from Texas to Maryland including 3 EF4s, 12 EF3s, 20 EF2s, 77 EF1s and 28 EF0s. More than a million homes and businesses lost power. With 32 tornado-related fatalities reported, this was the deadliest tornado outbreak since April 27-30, 2014. Damage was extensive and highly destructive in some places, with total damage costs reaching several billion dollars.
Another day of tornado activity was April 19, as 28 tornadoes were scattered along the Gulf coast states from Texas to Florida. Southern Mississippi and Alabama experienced the majority of these tornadoes. There was scattered damage and one fatality. The final noted tornado event for the month occurred during April 22 and 23, in which 47 and 27 tornadoes were reported, respectively. This event was a wider outbreak of tornadoes, as states impacted included Oklahoma, Texas, Louisiana, Mississippi, Alabama, Georgia and Florida. These tornadoes caused extensive damage and three deaths.
The next prolific tornado month of 2020 was August, in which there were 161 preliminary tornado reports. This was well above, nearly double, the 1991-2010 average of 83 tornadoes for the month of August. The majority of the U.S. August tornadoes occurred across several days and were focused in Minnesota, Illinois and up the East Coast from North Carolina to New Jersey from the influence of Tropical Storm Isaias. The most prolific tornado-producing days were August 3-4 in which 52 tornadoes developed across North Carolina, Virginia, Maryland, Delaware and New Jersey due to Tropical Storm Isaias. Many of these were weaker tornadoes (EF-0 and EF-1) that produced light damage to agriculture, structures and residences. However, there were several EF-2 tornadoes and one EF-3 tornado across coastal North Carolina and Virginia due to Isaias. The single EF-3 tornado that occurred in coastal North Carolina was responsible for two tornado fatalities.
A second notable event for the month occurred on August 10, in which a destructive Midwestern derecho produced at least 16 tornadoes across eastern Illinois and the Chicago metroplex. These weaker (EF-0 and EF-1) tornadoes did not produce any fatalities, but did cause scattered damage to homes and businesses.
For additional information on specific tornado and severe weather events during 2020, please visit our monthly reports, the Billion Dollar weather disasters report, the Storm Events Database, and NOAA's Storm Prediction Center.
Did You Know?
Tornado Count
Final monthly tornado counts are typically less than the preliminary count. This can be due to some phenomena being inaccurately reported as tornadic activity or a single tornado being reported multiple times. Tornado accounts are reported to the local National Weather Service forecast offices who are responsible for going into the field and verifying each tornado reported. This process often takes several months to complete. Once all reports have been investigated, the final count is published by the Storm Prediction Center (SPC).
The Tornado Monthly Climate Reports are written using the preliminary numbers because the final data is not available at the time of production. Historically, for every 100 preliminary tornado reports, at least 65 tornadoes are confirmed. An error bar is depicted on the tornado count graphic representing this uncertainty in the preliminary tornado count.
The following U.S. studies performed by SPC meteorologists offer deeper context and discussion regarding the frequency and distribution of tornado intensity climatologies:
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Edwards, R., H. E. Brooks, and H. Cohn, 2021: Changes in tornado climatology accompanying the Enhanced
Fujita scale. J. Appl. Meteor. Climatol., 60, 1465-1482
DOI: 10.1175/JAMC-D-21-0058.1. - Mccarthy, Daniel & Schaefer, Joseph. (2004). Tornado trends over the past thirty years. paper presented at 14th Conference on Applied Meteorology.