Sport Phillip Marine Chandlery Supplies
Forecasts
Australian Weather Influences
Causes of Weather Change
Atmosphere
Air Pressure
Weather Maps
Mornington Harbour
Weather For The Yachtsman
Web Cams - Port Phillip Bay
Tdal Forces
Beaufort Wind Scale
Weather of Port Phillip Bay
Swell
Waves

Beaufort Wind Scale

Beaufort Number
or Force

Wind Speed

DescriptionEffects Land / Sea
mphkm/hrknots
0<1<1<1CalmStill, calm air, smoke will rise vertically.

Water is mirror-like.

11-3
mph
1-5
kph
1-3
knots
Light AirRising smoke drifts, wind vane is inactive.

Small ripples appear on water surface.

24-7
mph
6-11
kph
4-6
knots
Light BreezeLeaves rustle, can feel wind on your face, wind vanes begin to move.

Small wavelets develop, crests are glassy.

38-12
mph
12-19
kph
7-10
knots
Gentle BreezeLeaves and small twigs move, light weight flags extend.

Large wavelets, crests start to break, some whitecaps.

413-18
mph
20-28
kph
11-16
knots
Moderate BreezeSmall branches move, raises dust, leaves and paper.

Small waves develop, becoming longer, whitecaps.

519-24
mph
29-38
kph
17-21
knots
Fresh BreezeSmall trees sway.

White crested wavelets (whitecaps) form, some spray.

625-31
mph
39-49
kph
22-27
knots
Strong BreezeLarge tree branches move,  telephone wires begin to "whistle", umbrellas are difficult to keep under control.

Larger waves form, whitecaps prevalent, spray.

732-38
mph
50-61
kph
28-33
knots
Moderate or Near GaleLarge trees sway, becoming difficult to walk.

Larger waves develop, white foam from breaking waves begins to be blown.

839-46
mph
62-74
kph
34-40
knots
Gale or Fresh GaleTwigs and small branches are broken from trees, walking is difficult.

Moderately large waves with blown foam.

947-54
mph
75-88
kph
41-47
knots
Strong GaleSlight damage occurs to buildings, shingles are blown off of roofs.

High waves (6 meters), rolling seas, dense foam, Blowing spray reduces visibility.

1055-63
mph
89-102
kph
48-55
knots
Whole Gale or StormTrees are broken or uprooted, building damage is considerable.

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

1164-72
mph
103-117
kph
56-63
knots
Violent StormExtensive widespread damage.

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

1273+
mph
118+
kph
64+
knots
HurricaneExtreme destruction, devastation.

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

1 knot = 1 nautical mile per hour = 6076 feet per hour = 1.15078 mph
1 mph = 1 mile per hour = 5280 feet per hour = 0.86898 knots per hour

 

Sport Phillip Marine services the boating, yachting & fishing needs of the Mornington Peninsula from Frankston, Daveys Bay, Mt. Eliza, Mornington, Mt. Martha, Safety Beach, Martha Cove, Dromana, Rosebud, Rye, Blairgowrie, Sorrento and Portsea on Port Phillip Bay to Yaringa, Warneet, Somers, Hastings, and Flinders on Westernport Bay. 

home | company profile | links | sitemap | contact us | disclaimer

©2009 Sport Phillip Marine