Wind Chill
The chilling effect of the wind can be represented by the lower temperature that would be required to produce the same chilling sensation for a person walking in calm conditions.
This is known as the wind chill equivalent temperature and is an important indicator in assessing the comfort of personnel spending periods outdoors. It is not an indication that an unheated inanimate object would cool below the ambient air temperature.
Wind chill becomes a hazard when heat is drawn away from the skin faster than the body can replace it. This may lead to frostbite or worse.
| Air Temperature (°C) | ||||||||||||
| Wind Speed at 1.5m elevation (mph) | 5 | 0 | -5 | -10 | -15 | -20 | -25 | -30 | -35 | -40 | -45 | -50 |
| 2 | 4 | -2 | -7 | -13 | -18 | -24 | -30 | -35 | -41 | -47 | -52 | -58 |
| 4 | 3 | -3 | -9 | -15 | -21 | -27 | -33 | -39 | -45 | -51 | -57 | -63 |
| 6 | 2 | -4 | -10 | -17 | -23 | -29 | -35 | -41 | -47 | -54 | -60 | -66 |
| 8 | 1 | -5 | -11 | -18 | -24 | -30 | -37 | -43 | -49 | -55 | -62 | -68 |
| 10 | 1 | -6 | -12 | -19 | -25 | -31 | -38 | -44 | -51 | -57 | -63 | -70 |
| 12 | 0 | -6 | -13 | -19 | -26 | -32 | -39 | -45 | -52 | -58 | -65 | -71 |
| 14 | 0 | -7 | -13 | -20 | -27 | -33 | -40 | -46 | -53 | -60 | -66 | -73 |
| 16 | -1 | -7 | -14 | -21 | -27 | -34 | -41 | -47 | -54 | -61 | -67 | -74 |
| 18 | -1 | -8 | -14 | -21 | -28 | -35 | -41 | -48 | -55 | -62 | -68 | -75 |
| 20 | -1 | -8 | -15 | -22 | -28 | -35 | -42 | -49 | -56 | -62 | -69 | -76 |
| 22 | -1 | -8 | -15 | -22 | -29 | -36 | -43 | -49 | -56 | -63 | -70 | -77 |
| 24 | -2 | -9 | -16 | -22 | -29 | -36 | -43 | -50 | -57 | -64 | -71 | -78 |
| 26 | -2 | -9 | -16 | -23 | -30 | -37 | -44 | -51 | -58 | -65 | -71 | -78 |
| 28 | -2 | -9 | -16 | -23 | -30 | -37 | -44 | -51 | -58 | -65 | -72 | -79 |
| 30 | -2 | -9 | -16 | -24 | -31 | -38 | -45 | -52 | -59 | -66 | -73 | -80 |
Frostbite may occur in 30 min or less
The above table is calculated using the latest wind chill equation adopted by the US and Canadian weather services in 2001
WCT = 13.12 + 0.6215T – 11.37V0.16 + 0.3965TV0.16
Where:
• WCT is the wind chill temperature in °C • T is the air temperature in °C • V is the wind speed at 10m in km/h • V = V1.5 * 1.5 where V1.5 is the wind speed at 1.5m
Note:
Wind chill is used to warn people of dangerous conditions due to low temperatures and winds. Therefore wind chill is not normally calculated for air temperatures above 5°C or wind speeds below 2mph.