Storm and Hurricane

      The Beaufort scale is an empirical measure that relates wind speed to observed conditions at sea or on land. Its full name is the Beaufort winds force scale, although it is a measure of wind speed and not of force in the scientific sense. The scale was devised in 1805 by Francis Beaufort (later Rear Admiral Sir Francis Beaufort), an Irish Royal Navy officer.

Effects Land / Sea

Slight damage occurs to buildings, shingles are blown off of roofs.   High waves (6 meters), rolling seas, dense foam, Blowing spray reduces visibility.

Trees are broken or uprooted, building damage is considerable.

Large waves (6-9 meters), overhanging crests, sea becomes white with foam, heavy rolling, reduced visibility.

Extensive widespread damage.

Large waves (9-14 meters), white foam, visibility further reduced.

Extreme destruction, devastation.

Large waves over 14 meters, air filled with foam, sea white with foam and driving spray, little visibility.

Km/h

75-88

89-102

103-117

118+

Wind speed

Knots

41-47

48-55

56-63

64+

Mp/h

47-54

55-63

64-72

73+

Beaufort

number of force

9

10

11

12

Wind and storm - Beaufort scale

Description

Strong Gail

Whole Gail or Storm

Violent Storm

Hurricane

Motivation articles