The Storm Prediction Center issues daily outlooks denoting the risk for severe weather and wildfires for specific regions in the United States. For severe weather, which includes the risk for thunderstorms, tornadoes, hail, and straight-line winds, there are five risk levels indicating the probability for these hazards: marginal, slight, enhanced, moderate, and high. For wildfires, there are three risk levels: elevated, critical, and extremely critical. [1]
Although outlooks issued by the Storm Prediction Center indicate the severity of a convective or wildfire threat, they do not always come to fruition. There have been many instances where a high risk outlook did not verify and only a few tornadoes occurred. [2] Conversely, there have been days where a lower risk level was issued and a major tornado outbreak occurred. Some of the deadliest severe weather and wildfire days in recent history did not have a high risk or extremely critical outlook issued. For example, the 2011 Joplin tornado, which killed 158 people occurred on a moderate risk day, [3] as did the tornado outbreak of December 10–11, 2021, which killed 89 people. [4] Furthermore, both the October 2017 Northern California wildfires, which killed 44 people, [5] and the 2023 Hawaii wildfires, which killed 101 people occurred under a critical fire weather outlook. [6]
The following are lists of the deadliest days in which various risk levels were issued for severe weather and wildfires.
Note: Fatality totals include deaths that took place in regions outside of the delineated outlook zones. Furthermore, only direct tornadic fatalities that occurred on the day that the outlook was issued for are included.
Fatalities | Event | Outlook | Region | Date |
---|---|---|---|---|
30 | Saragosa tornado [7] | Central and Midwestern U.S. | May 22, 1987 | |
24 | Evansville tornado outbreak [8] | Midwestern U.S. | November 6, 2005 | |
Tornado outbreak of March 2–3 [9] | Middle Mississippi River Valley | March 3, 2020 | ||
21 | Groundhog Day tornado outbreak [10] | Southeastern U.S. | February 2, 2007 | |
17 | Tornado outbreak of December 10–11 [11] | Eastern U.S. | December 11, 2021 | |
9 | Super Tuesday tornado outbreak [12] | Eastern U.S. | February 6, 2008 | |
New Year's Eve tornado outbreak [13] | Mississippi River Valley | December 31, 2010 | ||
8 | Tornado outbreak of April 20 [14] | Midwestern U.S. | April 20, 2004 | |
Tornado outbreak of November 14–16 [15] | Southeastern U.S. | November 16, 2006 | ||
7 | Tornado outbreak of March 15 [16] | Midwestern U.S. | March 15, 1984 |
Note: Enhanced risks have only been issued since October 22, 2014.
Fatalities | Event | Outlook | Region | Date |
---|---|---|---|---|
23 | Tornado outbreak of March 3 [17] | Southeastern U.S. | March 3, 2019 | |
13 | Tornado outbreak of December 26–28 [18] | Central U.S. | December 26, 2015 | |
10 | Easter tornado outbreak [19] | Southeastern U.S. | April 13, 2020 | |
8 | Tornado outbreak of January 12 [20] | Southeastern U.S. | January 12, 2023 | |
7 | Tornado outbreak of March 5–7 [21] | Midwestern U.S. | March 5, 2022 | |
Tornado outbreak of December 9–10 [22] | Middle Mississippi River Valley | December 9, 2023 | ||
6 | Tornado outbreak of January 10–11 [23] | Southeastern U.S. | January 11, 2020 | |
Tornado outbreak of April 22–23 [24] | Central U.S. | April 22, 2020 | ||
5 | Tornado outbreak of December 23–24 [25] | Southeastern U.S. | December 23, 2014 | |
Tornado outbreak of April 4–5 [26] | Ohio River Valley | April 5, 2023 |
Fatalities | Event | Outlook | Region | Date |
---|---|---|---|---|
159 | Tornado outbreak sequence of May 21–26 [3] | Midwestern U.S. | May 22, 2011 | |
76 | United States–Canada tornado outbreak [27] | Northeastern U.S., Great Lakes region | May 31, 1985 | |
72 | Tornado outbreak of December 10–11 [4] | Middle Mississippi River Valley | December 10, 2021 | |
42 | Kissimmee tornado outbreak [28] | Southeastern U.S. | February 22, 1998 | |
29 | Plainfield tornado [29] | Midwestern U.S., Great Lakes region | August 28, 1990 | |
28 | Central Texas tornado outbreak [30] | Central U.S. | May 27, 1997 | |
27 | March 1997 tornado outbreak [31] | Central U.S. | March 1, 1997 | |
Tornado outbreak of April 2 [32] | Midwestern U.S. | April 2, 2006 | ||
24 | Tornado outbreak of May 18–21 [33] | Central U.S. | May 20, 2013 | |
22 | Easter tornado outbreak [34] | Southeastern U.S. | April 12, 2020 | |
Tornado outbreak of March 24–27 [35] | Central U.S. | March 24, 2023 |
Fatalities | Event | Outlook | Region | Date |
---|---|---|---|---|
316 | Super Outbreak [36] | Southeastern U.S. | April 27, 2011 | |
57 | Carolinas tornado outbreak [37] | Southeastern U.S. | March 28, 1984 | |
48 | Super Tuesday tornado outbreak [38] | Middle Mississippi River Valley | February 5, 2008 | |
46 | Oklahoma tornado outbreak [39] | Central U.S. | May 3, 1999 | |
41 | Tornado outbreak of March 2–3 [40] | Ohio River Valley | March 2, 2012 | |
40 | Palm Sunday tornado outbreak [41] | Southeastern U.S. | March 27, 1994 | |
38 | Tornado outbreak sequence of May 2003 [42] | Central U.S. | May 4, 2003 | |
35 | Tornado outbreak of April 6–9 [43] | Southeastern U.S. | April 8, 1998 | |
34 | Tornado outbreak of November 9–11 [44] | Southeastern U.S., Ohio River Valley | November 10, 2002 | |
27 | Tornado outbreak of April 2–3 [45] [46] | Central and Midwestern U.S. | April 2, 1982 |
Note: Fatality totals include deaths that took place in regions outside of the delineated outlook zones. Furthermore, only direct wildfire fatalities that occurred on the day that the outlook was issued for are included.
Fatalities | Event | Outlook | Region | Date |
---|---|---|---|---|
101 | 2023 Hawaii wildfires [6] | [nb 1] | Hawaii | August 8, 2023 |
31 | October 2017 Northern California wildfires [5] | California | October 8, 2017 | |
19 | Yarnell Hill Fire [47] | Southwestern U.S. | June 30, 2013 | |
18 | North Complex Fire and Slater and Devil fires [48] | Western U.S. | September 9, 2020 | |
13 | October 2017 Northern California wildfires [49] | California | October 9, 2017 | |
12 | Cedar Fire [50] | California | October 26, 2003 |
Fatalities | Event | Outlook | Region | Date |
---|---|---|---|---|
85 | Camp Fire [51] | California | November 8, 2018 | |
12 | Texas–Oklahoma wildfires [52] | Southern Great Plains | March 12, 2006 | |
10 [53] | September 2020 Labor Day wildfires [54] | Northwestern U.S. | September 8, 2020 | |
7 | March 2017 Great Plains wildfires [55] | Southern Great Plains | March 6, 2017 | |
4 | April 2009 Texas wildfires [56] | Southern Great Plains | April 9, 2009 |
The Storm Prediction Center (SPC) is a US government agency that is part of the National Centers for Environmental Prediction (NCEP), operating under the control of the National Weather Service (NWS), which in turn is part of the National Oceanic and Atmospheric Administration (NOAA) of the United States Department of Commerce (DoC).
From May 3 to May 11, 2003, a prolonged and destructive series of tornado outbreaks affected much of the Great Plains and Eastern United States. Most of the severe activity was concentrated between May 4 and May 10, which saw more tornadoes than any other week-long span in recorded history; 335 tornadoes occurred during this period, concentrated in the Ozarks and central Mississippi River Valley. Additional tornadoes were produced by the same storm systems from May 3 to May 11, producing 363 tornadoes overall, of which 62 were significant. Six of the tornadoes were rated F4, and of these four occurred on May 4, the most prolific day of the tornado outbreak sequence; these were the outbreak's strongest tornadoes. Damage caused by the severe weather and associated flooding amounted to US$4.1 billion, making it the costliest U.S. tornado outbreak of the 2000s. A total of 50 deaths and 713 injuries were caused by the severe weather, with a majority caused by tornadoes; the deadliest tornado was an F4 that struck Madison and Henderson counties in Tennessee, killing 11.
A significant and destructive tornado outbreak that affected parts of the Midwestern United States and lower Great Plains in mid-May 2013. This event occurred just days after a deadly outbreak struck Texas and surrounding southern states on May 15. On May 16, a slow moving trough crossed the Rockies and traversed the western Great Plains. Initially, activity was limited to scattered severe storms; however, by May 18, the threat for organized severe thunderstorms and tornadoes greatly increased. A few tornadoes touched down that day in Kansas and Nebraska, including an EF4 tornado near Rozel, Kansas. Maintaining its slow eastward movement, the system produced another round of severe weather nearby. Activity significantly increased on May 19, with tornadoes confirmed in Oklahoma, Kansas, Iowa, Missouri, and Illinois. In Oklahoma, two strong tornadoes, one rated EF4, caused significant damage in rural areas of the eastern Oklahoma City metropolitan area; two people lost their lives near Shawnee. The most dramatic events unfolded on May 20 as a large EF5 tornado devastated parts of Moore, Oklahoma, killing 24 people. Thousands of structures were destroyed, with many being completely flattened. Several other tornadoes occurred during the day in areas further eastward, though the majority were weak and caused little damage.
On November 17, 2013, the deadliest and costliest November tornado outbreak in Illinois history took shape, becoming the fourth-largest for the state overall. With more than 30 tornadoes in Indiana, it was that state's largest tornado outbreak for the month of November, and the second largest outbreak recorded in Indiana. Associated with a strong trough in the upper levels of the atmosphere, the event resulted in 77 tornadoes tracking across regions of the Midwest United States and Ohio River Valley, impacting seven states. Severe weather during the tornado outbreak caused over 100 injuries and eleven fatalities, of which eight were tornado related. Two tornadoes—both in Illinois and rated EF4 on the Enhanced Fujita scale—were the strongest documented during the outbreak and combined for five deaths. In addition to tornadoes, the system associated with the outbreak produced sizeable hail peaking at 4.00 in (10.2 cm) in diameter in Bloomington, Illinois, as well as damaging winds estimated as strong as 100 mph (160 km/h) in three locations.
This page documents notable tornadoes and tornado outbreaks worldwide in 2017. Strong and destructive tornadoes form most frequently in the United States, Brazil, Bangladesh, and Eastern India, but they can occur almost anywhere under the right conditions. Tornadoes also develop occasionally in southern Canada during the Northern Hemisphere's summer and somewhat regularly at other times of the year across Europe, Asia, Argentina and Australia. Tornadic events are often accompanied with other forms of severe weather, including strong thunderstorms, strong winds, and hail.
Throughout the evening hours of April 9, 2015, an extremely violent and long-lived multiple-vortex tornado tore through the communities near Rochelle and in Fairdale, Illinois. Part of a larger severe weather event that impacted the Central United States, the tornado first touched down in Lee County at 6:39 p.m. CDT (23:39 UTC). It progressed through the counties of Ogle, DeKalb, and Boone before finally dissipating at 7:20 p.m. CDT. Along the tornado's 30.14-mile (48.51 km) path, numerous structures were heavily damaged or destroyed, especially in the small town of Fairdale where two fatalities and eleven injuries were recorded. A few well-constructed homes were swept completely away, indicative of peak winds near 200 mph (320 km/h), the upper bounds of an EF4 tornado. In the aftermath of the event, hundreds of citizens assisted in cleanup and recovery efforts. Economic losses from the tornado reached $19 million.
A small but damaging outbreak of 15 tornadoes impacted the Southeastern United States on February 7, 2017. The most damaging tornado of the outbreak was a large and powerful EF3 tornado. The tornado caused considerable damage along its path and left approximately 10,000 homes without electricity. 33 injuries occurred in the area after the tornado hit near Chef Menteur Highway with hundreds of structures sustaining moderate to significant damage along the ten-mile path. In response to the disaster, Governor John Bel Edwards declared a state of emergency.
The April 2018 North American storm complex brought a wide swath of severe and winter weather that affected much of Midwest across to the East Coast of the United States. This particular outbreak led to at least 73 confirmed tornadoes over a three-day period, most of which occurred across Arkansas and Louisiana during the evening hours of April 13. The most significant tornadoes were an EF1 that caused a fatality in Red Chute, Louisiana, early on April 14, an upper-end EF2 tornado that impacted eastern sections of Greensboro, North Carolina on April 15, causing 17 injuries, and a significant EF3 tornado that impacted areas from Lynchburg to Elon, Virginia, causing severe damage and at least 10 injuries.
The tornado outbreak of November 30 – December 2, 2018 was a late-season tornado outbreak that occurred across portions of the West South Central states and Midwestern United States. As a potent shortwave trough moved across the southern portions of the country, it was met with ample moisture return and destabilization, resulting in widespread severe thunderstorms that produced damaging winds, hail, and tornadoes. The event began late on November 30 in Oklahoma, spreading east and resulting in one fatality in Aurora, Missouri. Several tornadic supercells moved across portions of Illinois on December 1, and resulted in 29 confirmed tornadoes. This outbreak was the largest December tornado event on record in Illinois history, surpassing the December 1957 tornado outbreak sequence. The most significant tornado of the event was an EF3 that impacted Taylorville, Illinois, damaging or destroying hundreds of structures and injuring 22 people.
This page documents notable tornadoes and tornado outbreaks worldwide in 2020. Strong and destructive tornadoes form most frequently in the United States, Argentina, Brazil, Bangladesh, and eastern India, but can occur almost anywhere under the right conditions. Tornadoes also develop occasionally in southern Canada during the Northern Hemisphere's summer and somewhat regularly at other times of the year across Europe, Asia, Argentina, Australia and New Zealand. Tornadic events are often accompanied by other forms of severe weather, including strong thunderstorms, strong winds, and hail.
The tornado outbreak of January 10–11, 2020 was a two-day severe weather event stretching from the South-Central Plains eastward into the Southeast United States. An eastward-moving shortwave trough tracked across the continental United States through that two-day period, combining with abundant moisture, instability, and wind shear to promote the formation of a long-lived squall line. Hundreds of damaging wind reports were received, and 80 tornadoes occurred within this line, making it the third largest January tornado outbreak on record. Three tornadoes—an EF1 in eastern Texas, an EF2 in northern Louisiana, and an EF2 in western Alabama—led to a total of seven deaths, all in mobile homes. There were five other storm related deaths, including two due to icy roads in Lubbock, Texas, one due to drowning in Oklahoma, and one due to icy roads in Iowa. The system also brought a monthly record high temperature to Boston and Bridgeport. Extensive damage and several other injuries occurred as well. The severe weather event was notable in that it was forecast well in advance, with the Storm Prediction Center first highlighting the risk area a full week beforehand. Total damage from the event reached $1.1 billion according to the National Centers for Environmental Information.
There was a multi-day severe weather and tornado outbreak impacted the Southeastern and Mid-Atlantic United States from February 5–7. A powerful upper-level trough progressed eastward across the country, intersecting an abundant supply of moist air to produce severe weather. An eastward-propagating cold front supported a damaging squall line across the Southeast U.S. on February 5–6; supercell thunderstorms ahead of this line also produced numerous tornadoes. One EF1 tornado in the pre-dawn hours of February 6 killed one person in Demopolis, Alabama. On the morning of February 7, a secondary front progressed across Maryland and Virginia, unexpectedly leading to hundreds of damaging wind reports across Virginia, Maryland, Delaware, New Jersey, New York, Connecticut, Rhode Island, and Massachusetts. Five tornadoes were reported in the Washington, D.C., area, the most on record for a wintertime severe weather event. Across the three-day outbreak, 37 tornadoes were confirmed, including several that were strong and long-tracked.
This page documents notable tornadoes and tornado outbreaks worldwide in 2021. Strong and destructive tornadoes form most frequently in the United States, Argentina, Brazil, Bangladesh, and Eastern India, but can occur almost anywhere under the right conditions. Tornadoes also develop occasionally in southern Canada during the Northern Hemisphere's summer and somewhat regularly at other times of the year across Europe, Asia, Argentina, Australia and New Zealand. Tornadic events are often accompanied by other forms of severe weather, including strong thunderstorms, strong winds, and hail.
A significant early spring tornado outbreak occurred during the afternoon and evening hours of March 5, 2022 in the Midwest, primarily in the state of Iowa, before transitioning to a damaging wind event across northern parts of Illinois and Indiana. Multiple tornadoes were reported, several of which were produced by a dominant supercell thunderstorm in central Iowa. One long-track, low-end EF4 tornado caused major damage near the towns of Winterset and Norwalk, resulting in six fatalities. Multiple other supercells spawned along an area of moderate destabilization in northern Missouri, prompting further tornado warnings in southern Iowa, as they entered a highly favorable environment for maturing. Large hail and damaging wind gusts accompanied the storms, which continued their passage across the Midwestern states into overnight. More tornadic weather was confirmed in Arkansas and Missouri the next day and into the early morning of March 7. In addition to that, straight line winds killed one person near Hazel, Kentucky when a semi trailer was blown over on US 641. Another non-tornadic fatality occurred in western New York as the storm approached.
A late-season tornado outbreak in the Southern United States affected the states of Louisiana, Mississippi, Alabama, and Georgia, from the afternoon of November 29 into the morning of November 30, 2022. The outbreak was the result of an intense upper-level trough that materialized over the aforementioned states where increased moisture, atmospheric instability, and elevated wind shear were present, creating conditions highly conducive to supercell thunderstorms. Multiple tornadic storms developed in the risk area, producing numerous tornadoes. Several of these tornadoes were strong and destructive, prompting the issuance of multiple PDS tornado warnings. Two low-end EF3 tornadoes caused severe damage near Clarks, Louisiana and Tibbie, Alabama respectively while the Flatwood and Willow Springs communities north of Montgomery, Alabama was struck by an EF2 tornado, which caused two fatalities. Numerous weaker tornadoes also touched down, including a high-end EF1 tornado that caused considerable damage in Eutaw, Alabama. In all, 27 tornadoes were confirmed.
An intense low-pressure system produced widespread impacts across the United States in early March 2023. Additionally, an outbreak of 35 tornadoes affected 12 states from the Southern United States to the Great Lakes. In all, the storm system killed 13 people due to flooding and strong winds. At least 17 other people were injured.
A multi-day period of significant tornado and severe weather activity occurred across the Southern United States, Ohio Valley, and southern High Plains in mid-June 2023. Starting on June 14, tornadoes occurred in Texas, Alabama, and Georgia, where they caused large-scale damage to trees and structures. The tornado outbreak continued on June 15, where tornadoes occurred in five states, including one EF3 tornado which touched down in Perryton, Texas, causing three fatalities. More tornadoes touched down on June 16 in the southern and northeastern United States, including an unusual anticyclone tornado in Mobile and Baldwin counties in Alabama, where the tornado itself was associated with the anticyclonic bookend vortex of a powerful mesoscale convective system. More tornadoes occurred on June 17 and 18, including another EF3 tornado near Louin, Mississippi that destroyed numerous homes and other buildings, killed one person, and injured twenty-five others. This outbreak sequence was unusual in the sense that it produced strong tornadoes in the Deep South in June, despite the region's peak tornado season being March through May, along with the autumn months.
On June 20, a sequence of multiple severe weather events and tornado outbreaks began across large portions of the Great Plains, Midwestern, and Eastern United States as well as Manitoba and Ontario in Canada near the country borders. This includes the “historic” tornado outbreak on June 21. A slow moving trough interacted with extremely high moisture and atmospheric instability to produce favorable conditions for supercells. Large hail and damaging winds accompanied a multi-day tornado risk which produced multiple strong tornadoes, including a catastrophic high-end EF3 tornado in Matador, Texas on June 21, and another high-end EF3 tornado south of Granada, Colorado on June 23, and multiple EF2 tornadoes from Indiana to Kentucky on June 25. Reports of power outages, wind damage, hail damage, and tornadic damage accumulated across the affected region. In all, five people died from tornadoes, and three other non-tornadic deaths also occurred. Over 120 people were injured as well.