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Model Analyses and Forecasts Atl

Meteorological Conversions and Calculations

The Beaufort Wind Scale
Force Name

 Wind Speed knots       mph

0 Calm 0 0 Smoke rises vertically

Wave height: 0 m - Sea: Like a mirror

1 Light air 1-3 1-3 Smoke drifts with air

Wave height: 0.1 m (.25 ft) - Sea: Ripples - No foam crests

2 Light breeze 4-6 4-7 Weather vanes become active

Wave height: 0.2-0.3 m (0.5-1 ft) - Sea: Small wavelets - Not breaking

3 Gentle breeze 7-10 8-12 Leaves and small twigs move

Wave height: 0.6-1 m (2-3 ft) - Sea: Small wavelets - Crests begin to break

4 Moderate breeze 11-16 13-18 Small branches sway

Wave height: 1-1.5 m - Sea: Small waves becoming longer, numerous whitecaps.

5 Fresh breeze 17-21 19-24 Small trees sway - Waves break

Wave height: 2-2.5 m (6-8 ft) - Sea: Moderate waves - Many whitecaps

6 Strong breeze 22-27 25-31 Large branches sway

Wave height: 3-4 m (9.5-13 ft) - Sea: Larger waves forming - Whitecaps everywhere

7 Near gale 28-33 32-38 Whole trees sway - difficult to walk

Wave height: 4-5.5 m (13.5-19 ft) - Sea: Sea heaps up - White foam blown around

8 Gale 34-40 39-46 Twigs break off trees

Wave height: 5.5-7.5 m (18-25 ft) - Sea: Edges of crests break into spindrifts

9 Strong gale 41-47 47-54 Shingles blow off roofs

Wave height: 7-10 m (23-32 ft) - Sea: High waves - Sea rolls - Reduced visibility

10 Storm 48-55 55-63 Trees uprooted - Damage to buildings

Wave height: 9-12.5 m (29-41 ft) - Sea: Very high waves with overhanging crests

11 Violent Storm 56-63 64-73 Widespread damage

Wave height: 11.5-16 m (37-52 ft) - Sea: Exceptionally high waves

12 Hurricane Over 63 Over 73 Violent destruction

Wave height: 16+ m (52+ ft) - Sea: Sea completely white - Excessive foam


Wind Speed Converter

More Meteorological Conversions and Calculations

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Page last modified: Thursday, 12-May-2022 19:37:29 UTC