Reports
Alexander Keul, in a 2021 history in History of Geo- and Space Sciences, writes that since François Arago’s Sur le tonnerre (1837), the term ball lightning (Kugelblitz, foudre globulaire) stands for a still unexplained group of metastable luminous phenomena in atmospheric electricity. Keul 2021 In that outline, ball lightning appears seemingly random in time and space, lasts a few seconds, and disappears with traces or without; because of its unpredictable occurrence, most of the collected material remains anecdotal. Keul 2021
Keul quotes Rakov and Uman (2003) characterising ball lightning as “a phenomenon for which there exists numerous witness reports but little, if any, scientific documentation such as photographs, videotapes, or other scientific recordings.” Keul 2021 Keul writes that Rakov and Uman counted almost 5,000 observation reports. Keul 2021
How many written accounts?
The Royal Meteorological Society says there are more than 10,000 written accounts. Keul (2021), citing Rakov and Uman (2003), says they counted almost 5,000 observation reports. The figures are years apart and are not a precise census. This site quotes each source and does not treat either number as exact.
Cumbria, 27 July 2013
On the evening of Saturday 27 July 2013, after a thunderstorm in Cumbria, Kath Egerton reported a glow of light on the grass about 60 cm in diameter, then a slightly larger bright orangey-yellow light that passed rapidly in front of her, followed by an incredibly loud noise. RMetS Kath Egerton reported the observation to the Tornado and Storm Research Organisation (TORRO). RMetS
The Royal Meteorological Society published Kath Egerton's account as a possible ball-lightning report, not as a laboratory confirmation. The glow, the orangey-yellow light, and the loud noise are given in her wording.
Uppsala, 6 August 1944
On 6 August 1944, according to the same article, a ball of lightning smashed through a closed window in Uppsala, Sweden, leaving a circular hole about 5 cm in diameter, passed through a kitchen, and was recorded by a lightning-strike tracking system at Uppsala University. RMetS
Widecombe-in-the-Moor, 21 October 1638
The RMetS article recounts the Great Thunderstorm at a church in Widecombe-in-the-Moor, Devon, on 21 October 1638: four people reportedly died, and approximately 60 were injured, when a 2.4 m ball of fire was described as striking and entering the church. RMetS
That 1638 storm is often retold as ball lightning. The RMetS wording is "reportedly," and a 2.4 m "ball of fire" is what the article says was described. This site keeps the hedge and does not treat the church storm as a proven modern case.