Getting to know the wind speed by looking a visible cues is something that comes with practice, here is a useful table to give you an idea or what you are looking at.
Beaufort Wind Scale |
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Classification |
Wind Speed |
Visible effects |
| 0 – Calm | less than 1 km/h (0 m/s) | Smoke rises vertically |
| 1 – Light air | 0.5 to 1.5 m/s | Smoke drifts with air, weather vanes inactive |
| 2 – Light breeze | 2 to 3 m/s | Weather vanes active, wind felt on face, leaves rustle |
| 3 – Gentle breeze | 3.5 to 5 m/s | Leaves & small twigs move, light flags extend |
| 4 – Moderate breeze | 5.5 to 8 m/s | Small branches sway, dust & loose paper blows about |
| 5 – Fresh breeze | 8.5 to 10.5 m/s | Small trees sway, waves break on inland waters |
| 6 – Strong breeze | 11 to 13.5 m/s | Large branches sway, umbrellas difficult to use |
| 7 – Moderate gale | 14 to 16.5 m/s | Whole trees sway, difficult to walk against wind |
| 8 – Fresh gale | 17 to 20 m/s | Twigs broken off trees, walking against wind very difficult |
| 9 – Strong gale | 20.5 to 23.5 m/s | Slight damage to buildings, shingles blown off roof |
| 10 – Whole gale | 24 to 27.5 m/s | Trees uprooted, considerable damage to buildings |
| 11 – Storm | 28 to 31.5 m/s | Widespread damage, very rare occurrence |
| 12 – Hurricane | over 32 m/s | Violent destruction |
