2019 RDX. in Dashboard Thermometer is grossly inaccurate. Measures about 10 degrees below the actual outside temperature. Anyone else have this problem?

 

On my base 2022 RDX the outside temperature display can be adjusted. For my particular vehicle, the procedure is in the section of the Owner's Manual titled "Customized Features". Note that the display is subject to a lot of variables (sunlight, speed, rainy weather, car in front and in close proximity, etc.) so read the cautions.