x1 (temperature units) is the measured apparent temperature (humidex, wind chill) of x2 (location) by standard x3
x1 is typically jacke'o or falrenai. x3 is the system or equation used to correspond apparent temperature to regular temperature units (e.g. Canadian humidex, or AccuWeather RealFeel). Also see merli, glare, simlu, lenku, varcilmo, brife