Wtf.. Isnīt that a bit ridiculous?

My external temp gauge is off by 7c/12F, how can that happen overnite?
My first thought was that the foglights radiated some heat to the gauge as I use them exclusively in daytime but no.. Even with the foggies turned off the temp is 7c/12F higher than the actual outside temp.. Maybe a reset by disconnecting the battery will help, but if any of you guys have some idea as to why Iīd like the info so I can fix it!


Could it be that my temp gauge is psychic and is able to show the consequences of climate change?