Storm resulting in smaller disturbances such as dust devils and whirlwinds. There are many varieties and names for storms: A strict meteorological definition of a terrestrial storm is a wind measuring 10 or higher on the Beaufort scale, meaning a wind speed of 24.5 m/s (89 km/h, 55 mph) or more; however, popular usage is not so restrictive. Storms can last anywhere from 12 to 200 hours, depending on season and geography. In North America, the east and northeast storms are noted for the most frequent repeatability and duration, especially during the cold period. Big terrestrial storms alter the oceanographic conditions
Great Lakes Storm of 1913 indicating a storm warning with northwesterly winds. By late afternoon, the storm signal flags were replaced with a vertical sequence of red, white, and red lanterns, indicating that a hurricane with winds over 74 mph (119 km/h) was coming. (The word "hurricane" here does not refer to a tropical cyclone, but to Force 12 winds on the Beaufort scale.) The winds on Lake Superior had already reached 50 mph (80 km/h), and an accompanying blizzard was moving toward Lake Huron. By Saturday, the storm's status had been upgraded to "severe". The storm was centered over eastern Lake Superior, covering the