[boh-fert] 
| 1. | a scale of wind forces, described by name and range of velocity, and classified as from force 0 to force 12, or, sometimes, to force 17. |
| 2. | a scale of the states of sea created by winds of these various forces up to and including force 10. |
| Beau·fort scale (bō'fərt) n. A scale of wind velocity ranging from 0 (calm) to 12 (hurricane). [After Sir Francis Beaufort (1774-1857), British naval officer.] |
| Beaufort scale (bō'fərt) Pronunciation Key
A scale for classifying the force of the wind, ranging from 0 (calm) to 12 (hurricane). A wind classified as 0 has a velocity of less than 1.6 km (1 mi) per hour; a wind classified as 12 has a velocity of over 119 km (74 mi) per hour. Other categories include light air, five levels of breeze, four levels of gale, and storm. The scale was devised in 1805 as a means of describing the effect of different wind velocities on ships at sea. It is named after an admiral in the British navy, Sir Francis Beaufort (1774-1857). |
Beaufort scale
scale devised in 1805 by Comdr. (later Admiral and Knight Commander of the Bath) Francis Beaufort of the British Navy for observing and classifying wind force at sea. Originally based on the effect of the wind on a full-rigged man-of-war, in 1838 it became mandatory for log entries in all ships in the Royal Navy. Altered to include observations of the state of the sea and phenomena on land as criteria, it was adopted in 1874 by the International Meteorological Committee for international use in weather telegraphy.
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