The longest available instrumental record of temperature in the world is now available at the BADC. The monthly data starts in 1659.

The mean, minimum and maximum datasets are updated monthly, with data for a month usually available by the 3rd of the next month. A provisional CET value for the current month is calculated on a daily basis. The mean monthly data series begins in 1659. Mean maximum and minimum daily and monthly data are also available, beginning in 1878.

These historical temperature series are representative of the Midlands region in England, UK (a roughly triangular area of the United Kingdom enclosed by Bristol, Lancashire and London).

The following stations are used by the Met Office to compile the CET data: Rothamsted, Malvern, Squires Gate and Ringway.

But in November 2004, the weather station Stonyhurst replaced Ringway and revised urban warming and bias adjustments have now been applied to the Stonyhurst data after a period of reduced reliability from the station in the summer months.

The data set is compiled by the Met Office Hadley Centre.