| 0 --- Calm | less than 1 mph | Smoke rises vertically |
| 1 --- Light air | 1 - 3 mph | Smoke drifts with air, weather vanes inactive |
| 2 --- Light breeze | 4 - 7 mph | Weather vanes active, wind felt on face, leaves rustle |
| 3 --- Gentle breeze | 8 - 12 mph | Leaves & small twigs move, light flags extend |
| 4 --- Moderate breeze | 13 - 18 mph | Small branches sway, dust & loose paper blows about |
| 5 --- Fresh breeze | 19 - 24 mph | Small trees sway, waves break on inland waters |
| 6 --- Strong breeze | 25 - 31 mph | Lagre branches sway, umbrellas difficult to use |
| 7 --- Moderate gale | 32 - 38 mph | Whole trees sway, difficult to walk against wind |
| 8 --- Fresh gale | 39 - 46 mph | Twigs broken off trees, walking against wind very difficult |
| 9 --- Strong gale | 47 - 54 mph | Slight damage to buildings, shingles blown off roof |
| 10 -- Whole gale | 55 - 63 mph | Trees uprooted, considerable damage to buildings |
| 11 -- Storm | 64 - 73 mph | Widespread damage, very rare occurrence |
| 12 -- Hurricane | over 73 mph | Violent destruction |