> Home >

Hadley Centre Central England Temperature (HadCET) dataset

The CET dataset is the longest instrumental record of temperature in the world. 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 daily data series begins in 1772 and the mean monthly data in 1659. Mean maximum and minimum daily and monthly data are also available, beginning in 1878.

Brief description of the data

These daily and monthly temperatures are representative of a roughly triangular area of the United Kingdom enclosed by Lancashire, London and Bristol. The monthly series, which begins in 1659, is the longest available instrumental record of temperature in the world. The daily mean-temperature series begins in 1772. Manley (1953, 1974) compiled most of the monthly series, covering 1659 to 1973. These data were updated to 1991 by Parker et al (1992), who also calculated the daily series. Both series are now kept up to date by the Climate Data Monitoring section of the Hadley Centre, Met Office. Since 1974 the data have been adjusted to allow for urban warming: currently a correction of -0.2 °C is applied to mean temperatures.

Please note:

The real time diagnostics and data download pages are now using CET v2.0.0.0 published May 2022. Information on the improvements to the homogenisation
and data adjustments for this CET version can be found here.

Annual Mean CET — **Figure:** Mean temperature anomalies for each full year in the CET series against 1961-1990 climatology

Data are available from the download page without charge, but please read the terms and conditions.
CET datasets are freely available for use under Open Government License. However, please acknowledge the source if the data are used in any report or product.

Commercial and media enquiries

You can access the Met Office Customer Centre, any time of the day or night by phone, fax or e-mail. Trained staff will help you find the information or products that are right for you.
Contact the Met Office Customer Centre

References

When using the data set in a paper, the correct citation to use for HadCET is:

Parker, D.E., T.P. Legg, and C.K. Folland. 1992. A new daily Central England Temperature Series, 1772-1991. Int. J. Clim., Vol 12, pp 317-342 (PDF)

CET V2.0.0.0 Guidance Notes:

HadCET V2.0.0.0 release guidance notes (PDF)

Other relevant references include:

Manley,G. 1953. The mean temperature of Central England, 1698 to 1952. Q.J.R. Meteorol. Soc., Vol 79, pp 242-261.
Manley,G. 1974. Central England Temperatures: monthly means 1659 to 1973. Q.J.R. Meteorol. Soc., Vol 100, pp 389-405.
Parker, D.E. and Horton, E.B. 2005. Uncertainties in the Central England Temperature series since 1878 and some changes to the maximum and minimum series. International J.Climatology, Vol 25, pp 1173-1188. (PDF)

Other information

The graph above shows annual anomalies relative to the 1961-1990 average. The red line is a 21-point binomial filter, which is roughly equivalent to a 10-year running mean.
HadCET diagnostics for the current year and previous few years.
2006 was the warmest year on record for min HadCET. 2014 was the warmest year on record for mean HadCET. 2003 was the warmest year on record for max HadCET.
HadCET is produced using an operational system which relies on a number of components. Daily support is not available for this system, therefore the data may occasionally not be fully up-to-date. If you encounter any problems or want to request a more reliable service please contact us.