Understanding and anticipating weather conditions is essential for safe sailing. The Beaufort scale is one of the fundamental tools taught as part of the preparation for an offshore sailing license. Used to measure wind strength, this scale is an essential knowledge base for sailors of all levels.
The history and foundations of the Beaufort scale
The Beaufort scale was devised in 1805 by Francis Beaufort, a British naval officer. Its initial aim was to establish a standardized classification for wind strength, based on its observable effects at sea and on land. The scale has 13 levels, from 0 (dead calm) to 12 (hurricane), each corresponding to a specific wind speed and sea force.
The Beaufort scale table
Here are the levels and features of this âeuros¯ scale:
| Level | Description | Wind speed (km/h) | Observable effects at sea |
|
| Calm
| < 1
| Sea of oil
|
| 1
| Very light breeze
| 1 à 5
| Foamless wrinkles
|
| 2
| Light breeze
| 6 à 11
| Small swell, no foam
|
| 3
| A gentle breeze
| 12 à 19
| Small ripples
|
| 4
| Nice breeze
| 20 à 28
| Elongated waves
|
| 5
| Good breeze
| 29 à 38
| Crêtes d'écume
|
| 6
| Fresh wind
| 39 à 49
| Well-formed waves
|
| 7
| Grand frais
| 50 à 61
| Breaking swell
|
| 8
| Gale of wind
| 62 à 74
| Bottom slats
|
| 9
| Strong gale
| 75 à 88
| Heavy surf
|
| 10
| Storm
| 89 à 102
| Very big sea
|
| 11
| Violent storm
| 103 à 117
| Water mountains
|
| 12
| Hurricane
| > 118
| Total devastation
| Why is the Beaufort scale important for the offshore license?
When taking the offshore license exam, a good understanding of the Beaufort scale is required to :
Assess sailing conditions before going out to sea.
- Adapt route or strategic choices according to wind strength.
- Identify risky situations and know when it's best to stay alongside.
- This knowledge is particularly crucial in areas where winds can change rapidly, such as the Atlantic or Mediterranean coasts.
Tips for memorizing and using the Beaufort scale
To master this scale, we recommend the following stepsâeuros¯:
Associate each level with concrete situations: For example, force 3 = small waves, pleasant for a family outing.
- Practice regularly: Use weather reports to estimate wind strength based on the descriptions provided.
- Learn to interpret the effects on sea and land: observe the evolution of waves or the movement of trees to better integrate these notions.
- Use simulation tools: They enable you to visualize the impact of different wind forces on a boat, and train in conditions close to reality.
- The Beaufort scale in everyday life
In addition to its role in preparing for the offshore license, the Beaufort scale is a practical tool for all yachtsmen and professionals. It is used in marine weather reports to indicate wind forecasts and help sailors make the right decisions.
Practical cases for sailing :
Force 3, I take the first reef (between 15 and 20 knots of wind)
Force 4 I continue with 2nd reef (20 to 30 knots of wind)
Force 5 on 3rd reef (30 to 40 knots of wind)
Force 6 I'm staying put
The essential Beaufort scale
Mastering the Beaufort scale is essential for all sailors, whether beginners or experienced. This tool enables you to quickly assess wind conditions and their impact on navigation. For offshore license candidates, this skill is essential for passing the exam and sailing with complete peace of mind.
