Solar sensor temp on Solar Graph

I think my other solar% and extra sensor problems have now been solved (Thanks Brian). The only remaining problem is with the solar sensor temp on the solar graph. This consistently plots and displays a value 10degC higher than the reading on the sensor.

Using 9.73 and a WMR928N.

WD v9.73
My WMR-968 readings are Outside=51.3F, Solar sensor (extra #3)=59.4F, Solar sensor temp on Solar Graph=63.5F.
Solar setup values are: 1.1C for 0%, 27.7C for 100%. If I ever get a day with full sun, at the peak of sunshine, I plan to adjust the 100% value.

27.7C sounds very high compared to local outdoor temps for full sun. Do you ever reach that? I had mine at 13.1C but had to reduce it to 10.1C after I found I wasn’t reading 100% when the sun was shining in a clear blue sky.

27.7C sounds very high compared to local outdoor temps for full sun. Do you ever reach that? I had mine at 13.1C but had to reduce it to 10.1C after I found I wasn't reading 100% when the sun was shining in a clear blue sky.
I agree that 27.7C may be too high. I haven

1.1 and 15.1 and it works really well predicting the cloud coverage.