In contrast, the difference given for 81 to 10 of 0.8C to 6th November is comparing the 81 to 10 average for the first six days. This partly explains the large disparity between this figure and the 61 to 90 difference of 3.0C.
The difference of 3.0C shown to 6th November compared with the 61 to 90 average means the 61 to 90 figure used is 6.4C. However, this is the average for November, not the average for the first 6 days of November so overstates the difference.