Humidex is a measure of how hot we feel. It is an equivalent temperature intended for the general public to express the combined effects of warm temperatures and humidity.

If you know the temperature and relative humidity, the following chart can be used to determine the humidex rating. For example, if the temperature is 30°C and the relative humidity is 70%, the humidex rating is 41. This level is considered a level of "great discomfort" and exertion should be avoided