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WeatherBeaufort Wind Scale
Developed in 1805 by Sir Francis Beaufort of England
| Winds | WMO¹ | Appearance of Wind Effects | ||||
| Force | Knots | km/h | Classification | On Land | On the Water | |
| 0 | < 1 | < 1 | Calm | Calm, smoke rises vertically | Sea surface smooth and mirror-like | |
| 1 | 1–3 | 1–5 | Light Air | Smoke drift indicates wind direction, still wind vanes | Scaly ripples, no foam crests | |
| 2 | 4–6 | 6-11 | Light Breeze | Wind felt on face, leaves rustle, vanes begin to move | Small wavelets, crests glassy, no breaking | |
| 3 | 7–10 | 12-19 | Gentle Breeze | Leaves and small twigs constantly moving, light flags extended | Large wavelets, crests begin to break, scattered whitecaps | |
| 4 | 11–16 | 20–28 | Moderate Breeze | Dust, leaves, and loose paper lifted, small tree branches move | Small waves 0.3-1.2 meters becoming longer, numerous whitecaps | |
| 5 | 17–21 | 29–38 | Fresh Breeze | Small trees in leaf begin to sway | Moderate waves 1.2-2.4 meters taking longer form, many whitecaps, some spray | |
| 6 | 22–27 | 39–49 | Strong Breeze | Larger tree branches moving, whistling in wires | Larger waves 2.4-4 meters, whitecaps common, more spray | |
| 7 | 28–33 | 50–61 | Near Gale or Moderate Gale |
Whole trees moving, resistance felt walking against wind | Sea heaps up, waves 4-6 meters, white foam streaks off breakers | |
| 8 | 34–40 | 62–74 | Gale or Fresh Gale |
Whole trees in motion, resistance felt walking against wind | Moderately high (4-6 meters) waves of greater length, edges of crests begin to break into spindrift, foam blown in streaks | |
| 9 | 41–47 | 75–88 | Strong Gale | Slight structural damage occurs, slate blows off roofs | High waves (6 meters), sea begins to roll, dense streaks of foam, spray may reduce visibility | |
| 10 | 48–55 | 89–102 | Storm or Whole Gale |
Seldom experienced on land, trees broken or uprooted, "considerable structural damage" | Very high waves (6-9 meters) with overhanging crests, sea white with densely blown foam, heavy rolling, lowered visibility | |
| 11 | 56–63 | 103–117 | Violent Storm | Very rarely experienced, accompanied by widespread damage | Exceptionally high (9-14 meters) waves, foam patches cover sea, visibility more reduced | |
| 12 | 64 + | 118 + | Hurricane | Devastation occurs | Air filled with foam, waves over 14 meters, sea completely white with driving spray, visibility greatly reduced | |
Note 1: WMO = World Meteorological Organization
Temperature Comfort Scale
| Scale | Conditions |
| Extreme Cold | Wind Chill less than -18°C |
| Uncomfortably Cold | Wind Chill between -18°C and -1°C |
| Cold | Wind Chill between -1°C and 15.5°C |
| Comfortable | Temperature between 15.5°C and 26.5°C |
| Warm | Temperature between 26.5°C and 32°C |
| Uncomfortably Hot | Temperature greater than 32°C and Heat Index less than 37.5°C |
| Extreme Hot | Heat Index greater than 37.5°C |
- Wind chill - The cooling effect of any combination of temperature and wind. In Canada, wind chill is translated into a temperature that a person might feel when he or she went outside.
- Heat index - A combination of the temperature and the relative humidity to give a temperature of what it feels like to the human body on a hot muggy day.
