Temp on graph lags actual temp

The temperature shown above the rainfall/temp/humidity/dew point graph lags the temperature shown on the main part of the display by 0.1-0.2degC on a regular basis.

I’ve been watching the temperature drop this evening and the main temperature display has been showing a value 0.1 or 0.2degC lower than the temperature above the graph even when the graph has just been re-drawn.

the graph data is a 1 minute average

Thanks. That makes sense.