an Entity references as follows:
The present weather sensor (PWS) is a component of an automatic weather station that detects the presence of hydrometeors and determines their type (rain, snow, drizzle, etc.) and intensity. It works on a principle similar to a bistatic radar, noting the passage of droplets, or flakes, between a transmitter and a sensor. These instruments in automatic weather stations are used to simulate the observation taken by a human observer. They allow rapid reporting of any change in the type and intensity of precipitation, but include interpretation limitations.