Researchers at the Met Office Hadley Centre produce and maintain a range of gridded datasets of meteorological variables for use in climate monitoring and climate modelling. Indices are derived from RClimDex using high quality daily data from about 2500 temperature stations and 6000 precipitation stations. Most of the station indices (although not the raw daily data) are available from http://cccma.seos.uvic.ca/ETCCDMI/. Angular-distance weighting is used to interpolate the station data onto the required grid. For a more detailed description of the dataset and its production process, see the paper cited below. We strongly recommend that you read this paper before using the data.
[1]HadEX - global climate extremes indices.(2005).
[2] DOIAlexander, L. V.; Zhang, X.; Peterson, T. C.; Caesar, J.; Gleason, B.; Klein Tank, A. M. G.; Haylock, M.; Collins, D.; Trewin, B.; Rahimzadeh, F.; Tagipour, A.; Rupa Kumar, K.; Revadekar, J.; Griffiths, G.; Vincent, L.; Stephenson, D. B.; Burn, J.; Aguilar, E.; Brunet, M.; Taylor, M.; New, M.; Zhai, P.; Rusticucci, M.; Vazquez-Aguirre, J. L. (2006). Global observed changes in daily climate extremes of temperature and precipitation. doi:10.1029/2005JD006290