Note that the estimated mean value may not be equal to (max+min)/2 because there is always one more minimum value than maximum. This discrepancy is exaggerated during the first part of the month and when the nights have suddenly become significantly colder or warmer.
Averages so far this year:-
Average CET to August: 11.76
Normal CET to August: 9.83
Anomaly to August: 1.93
Anomaly to September (year so far) *: 1.89
* The anomaly for the year so far to September is calculated by taking an average
of the monthly anomalies, weighted by the days in the month so far, over the total days in the year so
This prevents the year so far anomaly value being skewed when calculated at the beginning of a month.
Comparison with Extreme Annual CETs:-
The highest annual mean CET ever recorded was
10.98, which is 1.52 higher than normal. To beat this
the anomaly must be higher than 0.48 for the remainder of this year
The lowest annual mean CET ever recorded was
6.86, which is -2.61 lower than normal. To beat this
the anomaly must be lower than -15.02 for the remainder of this year
Note that anomalies (and normals) quoted here are w.r.t. the period 1961-1990. This is a standard
period of reference for monitoring climate change as recommended by the WMO (World Met.
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