Human comfort is achieved when the environment provides the appropriate conditions to avoid feeling too cold or hot, according to Weather Prediction. Six factors influence human comfort: temperature, clothing, wind speed, sunlight, humidity and evaporative cooling.
Evaporative cooling refers to the process of perspiration cooling the body. For instance, when the wind blows on a warm day, perspiration cools and helps reduce body heat. The wind-chill factor is an important consideration when using clothing to keep warm on a cold day. Exposed skin will cool more quickly on a cold day when wind speed is high. Direct sunlight generally works to heat the body, while humidity limits the effectiveness of evaporative cooling and often causes discomfort when the temperature is warm.