...Beaufort Scale No. Designation of wtml Approximate wind velocity in mllrs per hour О Calm 3 or less 1 Light air 8 " " 2 Light breeze 13 " " 3 Gentle " 18 "" 4 Moderate breeze. .23 " " 5 Fresh " ..28 6 Strong " ..34 7" Moderate gale ... .40 8 Fresh " 48 9 Strong " ....56...