@Eme
Thank you for coming back to report how you solved your problem! Your comments will help other people.
I am a big fan of Frugal Tech and I think MySensors is great for that.
Alas, MySensors is not well supported anymore. Right now I'm having problems linking to the home page It's people like you and me that will keep MySensors going.
Thanks for your help.
OSD
I'm having the same / a simular issue of temperature related readings, but at a different temperature level (for me it must be > 14 degree). I massure the dew point as well (temperature = orange, dew point = yellow). It looks to be more related to water in the air than only to temperature.
@zboblamont have you been finally been able to find a solution?