This picture of the thermometer shows 160. It was taken in the middle of the bay on the 5th day.When making a batch of compost I want the temperatures to be above 131 degrees for at least 3 days to kill the weed seeds and pathogens. I keep a log to make sure that all areas reach temperature for at least 3 days.
Since all 9 sections have gotten above 131 for at least 3 days (see picture of log) I'm going to move the compost to another bay to make sure the outside material heats up too.
It's also important not to let the compost temperatures get above 165 degrees because it could start a fire.