Derby Day Thunderstorm 31 May 1911
, across parts of South East England. Significant weather event • 17 people killed along with 4 horses • 159 flashes of sheet or fork lightning in a 15 minute period around 17.30 recorded at Epsom • Hail 1½ to 2 inches in diameter fell at Sutton • Landslides closed both the Great Western Railway at Park