The Central England Temperature (HadCET) seasonal series starts in 1659 for mean temperature and 1878 for minimum and maximum temperature.

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 seasonal temperature series are derived as the mean of the monthly temperature series values.

Stations used in the construction of the CET daily series between 1772 and 1852 include: Kennington, Crane Court, Lyndon Hall, Syon House, Somerset House, Greenwich Observatory, Chiswick

Stations used in the construction of the CET daily series from 1853 onwards include: Radcliffe (Oxford), Cambridge (legacy), Ross-on-Wye, Rothamsted, Malvern, Stonyhurst, Ringway, Squires Gate, Pershore College

The current station selection used is Rothamsted, Stonyhurst and Pershore College.

The dataset is compiled by the Met Office Hadley Centre.

Latest provisional release data are available via the Hadley Centre Observations website (https://www.metoffice.gov.uk/hadobs/hadcet/data/download.html).

The version controlled CET series is updated annually (February-March), with the previous complete year’s values refreshed to ensure that data acquisition and quality control procedures have been completed and ensure the most accurate station temperature values are used. Each version of the dataset will include data up until the end of the previous complete year and an incremental version number will be updated.

The CET datasets employ the following version control protocol:

Version Vx.y.z.a:
• x – major changes – e.g. change in scientific methodology
• y – minor changes – e.g. small bug fixes or updates to diagnostics pages
• z – incremental changes
• a – reserved for use internally

The standard annual release cycle of CET will constitute an incremental release (z). However, if more substantial
changes have been made to the codebase, scientific methodology or source data values, then this may warrant a minor (y) or major (x) version release. (Note, these are applied to a cohort of datasets together - i.e. apply to the seasonal, monthly, daily and adjustment datasets as a coordinated version release).

This new version of the datasets supersedes the previous version.