Try it
Heat calculator
The same math that runs the Now screen. Set the air and humidity, and the instrument answers.
Caution
Take water and breaks.
Sweat evaporates slower now, so you heat up faster.
Caution. 85°F WBGT. Take water and breaks.
WBT °F72.1°
The readings assume shade. Direct sun adds heat the method does not see. In open sun, act one band earlier.