Five-and-ten system

{
  "id": "MLC-T-MET-005604",
  "term": "Five-and-ten system",
  "field": "Meteorology and atmospheric science",
  "definition": "A method for classifying the intensity of tornadoes based on the average path length and path width of a group of tornadoes occurring in an outbreak. The system uses a logarithmic scale where the class number is determined by the sum of the logarithms of the mean path length in miles and the mean path width in yards. It was developed by meteorologist Tetsuya Fujita as an objective measure of tornado outbreak severity.",
  "url": "https://mlchart.com/terminology/meteorology/five-and-ten-system/"
}