During 2024, tornadoes and tornado outbreaks were extensively researched by meteorologists and engineers across the world. Some research and publications included: the effects of "Tornado Brain", the detection of tornadic infrasound, several mobile radar observations of tornadoes, including the measurement of tornadic winds over 300 mph (480 km/h), the idea of tornado alley shifting eastward, and many other things.
In January 2024, researchers with Colorado State University’s Department of Atmospheric Science, published an analysis and database of 74 tornadoes which occurred in South America. According to the researchers, this was the first time tornadic environments was studied across South America.[1]
On February 8, meteorologist and storm chaser Reed Timmer, along with Mark Simpson, Sean Schofer, Curtis Brooks, published a paper about the design of and information about a new meteorological rocket probe which can be launched into tornadoes. The researchers launched one of these rocket probes into the 2019 Lawrence–Linwood EF4 tornado. The probe recorded winds of 85.1 m/s (190 mph; 306 km/h) during its first rotation around the tornado and also recorded a pressure drop of 113.5 hPa (113.5 mb) inside the tornado. The probe also recorded that the tornado's updraft was 65.0 m/s (145 mph; 234 km/h). The tornado threw the probe 32 mi (51 km), where the researchers were able to recover it.[5][6]
In March 2024, Anthony W. Lyza, Matthew D. Flournoy, and A. Addison Alford, researchers with the National Severe Storms Laboratory, Storm Prediction Center, CIWRO, and the University of Oklahoma's School of Meteorology, published a paper where they stated, ">20% of supercell tornadoes may be capable of producing EF4–EF5 damage" and that "the legacy F-scale wind speed ranges may ultimately provide a better estimate of peak tornado wind speeds at 10–15 m AGL for strong–violent tornadoes and a better damage-based intensity rating for all tornadoes". In their conclusion, the researchers also posed the question: "Does a 0–5 ranking scale make sense given the current state of understanding of the low-level tornado wind profile and engineering of structures?"[7]
In April 2024, the European Severe Storms Laboratory and the Czech Hydrometeorological Institute, along with seven other European organizations, published a detailed damage survey and analysis on the 2021 South Moravia tornado using the International Fujita scale.[8] Also in April, Timothy A. Coleman, with the University of Alabama in Huntsville (UAH), Richard L. Thompson with the NOAA Storm Prediction Center, and Dr. Gregory S. Forbes, a retired meteorologist from The Weather Channel published an article to the Journal of Applied Meteorology and Climatology stating, "it is apparent that the perceived shift in tornado activity from the traditional tornado alley in the Great Plains to the eastern U.S. is indeed real".[9][10] On April 26, a Doppler on Wheels (DOW) mobile radar truck measured 1-second wind speeds of approximately 224 mph (360 km/h) at a height of ~282 yards (258 m) as a tornado passed near Harlan, Iowa, causing widespread destruction.[11][12] On April 30, strong tornado near Hollister, Oklahoma passed close to a NEXRAD radar. The radar measured a tornado vortex signature with a gate-to-gate of 260 miles per hour (420 km/h) about 600 feet (200 yd; 180 m) above the surface.[13][14]
In mid-April, the National Severe Storms Laboratory along with Texas Tech University begin the Low-Level Internal Flows in Tornadoes (LIFT) Project, with the goal to collect data from the “damage layer” of tornadoes; from ground level to 20 m (22 yd) above the surface. The LIFT project deployed 11 times between April-June, gathering data from “numerous successful intercepts”.[15]
In May 2024, researchers with the University of Western Ontario's Northern Tornado Project and engineering department conducted a case study on the 2018 Alonsa EF4 tornado, the 2020 Scarth EF3 tornado, and the 2023 Didsbury EF4 tornado. In their case study, the researchers assessed extreme damage caused by the tornado which is ineligible for ratings on the Canadian Enhanced Fujita scale or the American Enhanced Fujita scale (EF-scale). In their analysis, it was determined all three tornadoes caused damage well-beyond their assigned EF-scale ratings, with all three tornadoes having EF5-intensity winds; Alonsa with 127 metres per second (280 mph; 460 km/h), Scarth with 110–119 metres per second (250–270 mph; 400–430 km/h), and Didsbury with 119 metres per second (270 mph; 430 km/h). At the end of the analysis, the researchers stated, "the lofting wind speeds given by this model are much higher than the rating based on the ground survey EF-scale assessment. This may be due to the current tendency to bias strong EF5 tornadoes lower than reality, or limitations in conventional EF-scale assessments".[17] Also during May, Timothy J. Dolney with Pennsylvania State University, published an new analysis of the 1985 United States–Canada tornado outbreak, specifically focusing on the state of Pennsylvania and Tornado Watch #211 issued by the National Weather Service for the tornado outbreak.[18]
Also in May, Doctor Bin Liang with the University of Mississippi published a paper on the results of a field research project on tornadoes. During the project, Liang was able to determine “that tornadoes emit dominant low-frequency infrasound between 0.5−1.2 Hertz”, after examining tornadic and non-tornadic supercells.[19]
On May 21, a violent EF4 tornado struck the town of Greenfield, Iowa. As the tornado moved through the town, a Doppler on Wheels measured winds of at least >250 mph (400 km/h), "possibly as high as 290 mph (470 km/h)" at 48 yards (44 m) above the surface.[21] Pieter Groenemeijer, the director of the European Severe Storms Laboratory, noted that "on the IF-scale, 250 mph measured below 60 m above ground level is IF4 on the IF-scale, 290 mph is IF5."[22] The peak wind speed estimate was revised to between 309 mph (497 km/h) and 318 mph (512 km/h), a figure "among the highest wind speeds ever determined using DOW data", on June 22, 2024.[23]
A few weeks after the tornado, the National Oceanic and Atmospheric Administration released details about an experimental warning system which was tested before and during the tornado. This new warning system, named Warn-on-Forecast System (WoFS), was created by the Hazardous Weather Testbed housed in the National Weather Center in Norman, Oklahoma. During the experiment and test, the WoFS gave a high indication of “near-ground rotation” in and around the area of Greenfield, Iowa between 2-4 p.m. According to the press release, 75-minutes later, the violent EF4 tornado touched down. Scientists with the National Severe Storms Laboratory were able to give local National Weather Service forecasters a 75-minute lead time for the tornado.[24]
On July 30, Andrew Mercer, Kenneth Swan, and Adonte Knight with Mississippi State University published the first quantitative definition for how to define a tornado outbreak. The researchers also analyzed intensity and frequency trends of tornado outbreaks between 1960 and 2021. In their analysis, it was determined that between 1960-2021, the United States experienced 6,723 individual tornado outbreaks and that there is also a downward trend of 0.25 tornado outbreaks per year.[35]
A Doppler on Wheels recorded a wind gust of ~79 m/s (180 mph) about 258 m (846 ft) above the radar level. Peak ground level wind speed was estimated around 224 mph (360 km/h).[37][38][39]
A Doppler on Wheels recorded winds of 263–271 mph (423–436 km/h) approximately 30–50 m (98–164 ft) above the radar level. Following calculations to more accurately determine peak wind speeds, it was published that ground-relative winds of 309–318 mph (497–512 km/h) could be observed briefly to the immediate east of the main circulation.[41]
^Kosiba, Karen (28 April 2024). "@DOWFacility research RE many peoples' questions"(Post on 𝕏). 𝕏 (Formerly Twitter). @karen_kosiba. Retrieved 29 April 2024. These data: Height ~258 m ARL (see 2) Gate 12m/beam 122m, gusts ~1sec
^Kosiba, Karen A.; Lyza, Anthony W.; Trapp, Robert J.; Rasmussen, Erik N.; Parker, Matthew; Biggerstaff, Michael I.; Nesbitt, Stephen W.; Weiss, Christopher C.; Wurman, Joshua; Knupp, Kevin R.; Coffer, Brice; Chmielewski, Vanna C.; Dawson, Daniel T.; Bruning, Eric; Bell, Tyler M.; Coniglio, Michael C.; Murphy, Todd A.; French, Michael; Blind-Doskocil, Leanne; Reinhart, Anthony E.; Wolff, dward; Schneider, Morgan E.; Silcott, Miranda; Smith, Elizabeth; Aikins, oshua; Wagner, Melissa; Robinson, Paul; Wilczak, James M.; White, Trevor; Bodine, David; Kumjian, Matthew R.; Waugh, Sean M.; Alford, A. Addison; Elmore, Kim; Kollias, Pavlos; Turner, David D. (12 June 2024). "The Propagation, Evolution, and Rotation in Linear Storms (PERiLS) Project". Bulletin of the American Meteorological Society. -1 (aop). American Meteorological Society. doi:10.1175/BAMS-D-22-0064.1.
^Kosiba, Karen (28 April 2024). "@DOWFacility research RE many peoples' questions"(Post on 𝕏). 𝕏 (Formerly Twitter). @karen_kosiba. Retrieved 29 April 2024. These data: Height ~258 m ARL (see 2) Gate 12m/beam 122m, gusts ~1sec