All weather service temperatures are 10-20 degrees low. Currently have NetAtmo (which is reasonably correct, but only 1 daily measurement with no periodic reading), NOAA, OpenWeatherMap, Wunderground, and ForecastIO programmed.  I am referencing actual readings at my location from NOAA, for example, versus what my RainMachine indicates.

Noticed this a couple of weeks ago, and anticipated an "adjustment", which has not occurred. Therefore, RainMachine is in constant "Freeze Protect" when the temperature is well above threshold.