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
Hurricane Severity Index the index uses a 50-point scale, with half of the total based on wind intensity, and half based on the wind fields. Wind radii data from every named storm since 1988 was studied. From these data, average wind radii ranges of four wind fields (39, 58, 74, and 100 mph) were calculated. Once the typical ranges were established, each wind field range was divided into sections. Since hurricane-force winds are much more damaging than tropical storm-force winds, the size scale is weighted more toward the 74 and 100 mph wind fields. With the HSI, a tropical storm can receive no