What environmental factor is known to affect ultrasonic wind sensors significantly?

The environmental factor that is known to significantly affect ultrasonic wind sensors is heavy rainfall. Ultrasonic wind sensors operate by emitting ultrasonic signals between transducers and measuring the time it takes for these signals to travel between them. When heavy rainfall occurs, raindrops can interfere with the ultrasonic signals, causing scattering or attenuation. This interference can lead to inaccurate wind speed and direction readings, as the sensors may not be able to effectively measure the wind when these drops disrupt the signal path.

While strong sunlight, high humidity, and cold temperatures can also influence the performance of sensors and other measurement devices, their impact is generally less direct and pronounced compared to the effects of heavy rainfall. Strong sunlight might affect temperature readings or solar radiation sensors but does not interfere with ultrasonic signals per se. High humidity could affect the air density and may introduce some level of error in readings, but it does not physically obstruct the ultrasonic wave path. Cold temperatures can affect the functioning and calibration of electronic components but do not have a significant effect on the actual performance of the ultrasonic signal itself.