WBGT is a measure of the heat stress in direct sunlight, which takes into account: temperature, humidity, wind speed, sun angle, and cloud cover (solar radiation). This differs from the heat index, which takes into consideration temperature and humidity and is calculated for shady areas. For more background info on WBGT

WBGT is calculated as the weighted sum of natural wet bulb temperature (Tnwb), globe temperature (Tg), and dry bulb/ambient temperature (Ta): WBGT = 0.7Tnwb + 0.2Tg + 0.1Ta.

This calculator is only an estimate. We gather the most up to date weather for your location and we estimate your WBGT using the heat and mass transfer algorithm of Liljegren et al. (2008)

We get our weather data from OpenWeather. OpenWeather provides an up to date forecast every 10 minutes.

We do not know the weather at your exact location. In order to get the most accurate WBGT for your location, we would need to know the weather at your exact location. We are unable to get weather from your exact location, so we use the OpenWeather location closest to your location.

We estimate the wet bulb temperature for your location. The wet bulb temperature is needed to calculate the WBGT. Unfornately, this is not a measurement provided by OpenWeather and most other weather service providers. Instead we use a formula the uses relative humidity and temperature(dry bulb) to estimate your temperature. This wet bulb estimate is accurate between -1°C to +0.65°C when relative humidity is between 5% and 99%.

Yes, there are many companies that sell stationary or hand held equipment designed to measure the WBGT wherever the equipment is located. Accuracy is dependent on the make and model of the equipment. Please consult manufacturer specifications for more information.