This article looks at the November and December tornadoes experienced throughout the United States in 2021.
Generally speaking, tornadoes can occur any time of the year. Whenever hot, moist air close to the ground collides with cooler, drier air above, thunderstorms and unstable air conditions can be created. That being said, by this time of year, the humidity and instability required for the formation of tornadoes are usually limited. This is particularly true in areas of the United States (U.S.) outside of the South. However, in 2021, we have witnessed significant changes regarding considerations for what is “common” for natural hazards, with increases in their frequency and severity across the globe.
2021 has been a particularly damaging year for the U.S., with the country having experienced a number of significant events, from wildfires burning across California to the mass flooding in Louisiana. In October, the National Centre for Environmental Information released a document on billion-dollar weather and climate disasters. Within, the agency states that as of October 8th the country experienced 18 natural disaster events this year alone, including droughts, wildfires, floods, severe storms, tropical cyclones and winter storms – with losses exceeding $1B each (see Figure 1).
While their next report won’t be released until January 2022, it is safe to say there will be more billion-dollar weather and climate disasters added to the list for 2021.
In the U.S., the months of November and December (to date) have been uncharacteristically warm, making way for a series of tornadoes across the country. On November 13th a total of 11 twisters touched down in New York, Rhode Island, and Connecticut. The 4 that landed in Connecticut are the only November tornadoes recorded in the state’s history. Why did they occur? Unstable conditions from a strong cold front meeting Atlantic waters that were much warmer than usual (up to 6°). As well, 5 of the 11 twisters touched down in Suffolk County, New York, where significant damage was done to homes and businesses, and even managed to overturn several airplanes at Brookhaven Airport.
Almost a month later, on December 10th and 11th, a much larger and much more violent surge of tornadoes ripped through a total of 9 states including Alabama, Missouri, Arkansas, Tennessee, Illinois, Kentucky, Indiana, Ohio, and Georgia. This event was made possible as a trough (elongated area of lower air pressure) progressed eastward across the U.S., interacting with an unseasonably moist and unstable environment across the Mississippi Valley.
Many people were feared dead, with communities across the Midwest and South spending the 11th sifting through the rubble. The state of Kentucky was hit by 4 tornadoes, 1 of which stayed on the ground for more than 200 miles. According to Kentucky Governor Andy Beshear, at least 70 deaths have been reported, but the state’s death toll is likely to increase by more than 100. In Mayfield, Kentucky, about 110 people had been huddled inside of a candle factory when a twister ripped through it. Around 40 people were able to be rescued, but Governor Beshear believes dozens more lost their lives. At a news briefing on the 11th, local officials reported they were struggling to dig through the debris due to blocked roads and lost water and electrical services. At the briefing, Beshear stated, “This has been the most devastating tornado event in our state’s history. The level of devastation is unlike anything I have ever seen.”
Kentucky wasn’t the only state that was hit hard. In Illinois, an Amazon warehouse was destroyed. As a tornado hit the facility, the roof was torn off, several walls collapsed, and 6 people were killed. A woman inside the facility reported that an individual she was sheltering with inside had been “bent in half” by the rubble. Thankfully no other fatalities were reported in Illinois outside of the Amazon incident.
For a few days the U.S. had a break from tornadoes, until December 15th when a derecho and tornado outbreak event struck parts of the Great Plains and Midwest, characterized by record-breaking winds and over 20 tornadoes across 4 states. 5 deaths have been reported, with most involving crashes. In Iowa, a truck driver was killed after their vehicle was struck by a particularly strong gust of wind. In Kansas, 3 individuals died in car crashes related to the storm, and in Minnesota, a man died after a 40 ft tree crushed him.