visit Severn boating

The Beaufort Wind Scale and Velocity Conversions with descriptions for Land and Sea

ForceDescriptionKnotsmphkm/h Wave Ht Sea DescriptionOn Land
0Calm< 1< 1< 1 - Sea like a mirrorSmoke rises vertically
1Very Light1-31-31-50.1mRipplesSmoke drifts
2Light breeze4-64-76-110.2mSmall waveletsWind felt on face. Rustles leaves
3Gentle breeze7-108-1212-190.6mWave crests begin to breakLeaves and flags move
4Moderate breeze11-1613-1820-291.0mSmall waves frequent white crestsPaper blown about. Small branches move
5Fresh breeze17-2119-2430-392.0mModerate waves. Many white crestsLarge branches sway
6Strong breeze22-2725-3140-503.0mLarge waves. White foam crestsSmall trees sway
7Near gale28-3332-3851-614.0mSea heaps up white foam in streaksLarge trees sway. Difficult to walk
8Gale32-4039-4662-745.5mModerate high waves breaking crests foam streaksSmall trees blown down
9Strong gale41-4747-5475-877.0mHigh waves dense foam streaksStructural damage. Chimney pots removed
10Storm48-5555-6388-1019.0mVery high waves. Sea surface appears whiteTrees uprooted. Much structural damage
11Violent storm56-6364-73102-11711.5mExceptional high waves sometimes concealing small shipsWidespread damage
12Hurricane> 64>74>11914+mAir filled with foam and spray. Sea whiteWidespread damage

Yachtsman, small boat sailors and skippers of motor cruisers should note with caution, the wide range of wind velocities covered by the word 'breeze'.  For most pleasure sailors a 'fresh breeze' (Force 5) will prove demanding especially if the wind is against tide!