This is a dataset of monthly-average near surface air temperature observations measured at 11865 weather stations around the world, compiled by the Climatic Research Unit (CRU) at the University of East Anglia (UEA). It spans the period 1781-2021, though the number of stations with available data varies greatly over time (from 43 stations in 1781 to 8271 in 1978). An "exposure bias adjustment" for the bias arising from the transition from pre-Stevenson screen to Stevenson screens has been applied to mid-latitude stations (though unadjusted data are also provided). Values that fail to meet simple physical plausibility and statistical outlier criteria are removed (though a version with these values retained is also provided). Estimated normals (averages for each station during the 1961-1990 baseline) for each station and month of the year are also provided, and some of these are estimated with data gaps filled with local expectation kriging (LEK). Standard deviations of monthly temperatures are also provided. More details are given in the readme file. When using these data, please cite Taylor et al. (2025).