Beaufort Scale Back to Valhalla's Mooring Page
A numerical scale for relating wind speed and sea state, devised by the British Admiral Sir Francis Beaufort in 1805. Beaufort numbers (or forces) range from force 0 (calm) to force 12 (hurricane). Sometimes (and originally) called the Beaufort scale of wind forces.
Click on the force number below to see a description of that force. Use your browser's 'back' button to return.
FORCE (KTS)
0 (0) 1 (1-3) 2 (4-6) 3 (7-10) 4 (11-16) 5 (17-21) 6 (22-27)
7 (28-33) 8 (34-40) 9 (41-47) 10 (48-55) 11 (56-63) 12 (64+)
Note in these definitions the use of 'smack'. A 'smack' is the type of popular (1800's) British fishing vessel whose response to the wind and waves were used as a standard in the original Beaufort scale. Thought to be a 30 foot, double-ended, open-deck sailing vessel with a gaff-rigged main.
