What is the heat index?

Those who live in a hot, humid climate, have heard all the lament: "It's not warm, it's moisture!" Especially hot, sticky day. The heat index has a real air temperature and the relative humidity factors to achieve the temperature that the human body feels. Because humidity has a real effect on the ability of the human body to effectively cool efficiently, measurement of the temperature that the body feels under the influence of high heat and humidity, it is important that people in safe heat disorders. If the moisture is high, because the air is already saturated with water, sweating does not evaporate so fast or not at all. Therefore, when it is not only hot, but also humid, the temperature feels warmer because the body cannot cool effectively.

The thermal index is calculated in the shade, with a light wind. Direct solar exposure can increase the thermal index by up to 15 degrees Fahrenheit (about 8 degrees Celsius). Relative humidity is the ratio of the amount of water vapor in the air to as much steam as possible. The formula is very complicated,Especially for non-mathematics, so there are numerous heat graphs on the Internet. In most areas, hot and sufficiently humid to require the heat index, the weather prognostics usually provide a real temperature along with the temperature of the thermal index.

For example, the temperature of the thermal index for 90 ° F (32 ° C) a day with a relative humidity of 90% would be 121 ° F (49 ° C). At 80% humidity, the temperature of 95 ° F (35 ° C) would feel like 133 ° F (56 ° C). The highest recorded reading of the heat index was 8 July 2003 in Dhahran, Saudi Arabia. The relative humidity was 67% and the temperature was 108 ° F (42 ° C), so it felt like 176 ° C (80 ° C). When a person compares the desert Towns of a relatively high temperature to a southern city near an ocean with a lower temperature, it may feel warmer in the southern city because the relative humidity is pushing the thermal index.

Thermal index that is called humidex is usefula tool when predicting heat failures. By calculating the thermal index, medical officials can issue citizens a useful warning about potential heat dangers. Temperatures from 90 ° to 105 ° F (32 ° to 41 ° C) can contribute to exhaustion of heat and heat. From 105 ° to 130 ° F (41 ° to 54 ° C) can be added to the list of possible complications of thermal pulls. During the prolonged period of exposure to temperatures above 130 ° F (54 ° C) is almost guaranteed.