World Weather Records (WWR) have been published since 1927, and include monthly mean values of pressure, temperature, precipitation, and where available, station metadata notes documenting observation practices and station configurations. Data were supplied by National Meteorological Services as members of the World Meteorological Organization (WMO).
The First Issue included data from earliest records available at that time up to 1920. Data have been collected for periods 1921-30 (2nd Series), 1931-40 (3rd Series), 1941-50 (4th Series), 1951-60 (5th Series), 1961-70 (6th Series), 1971-80 (7th Series), 1981-90 (8th Series), and 1991-2000 (9th Series).
The present series continues the record of monthly mean values of station pressure, sea-level pressure, temperature, and monthly total precipitation. It is available from the World Data Center for Meteorology which is operated by the National Climatic Data Center (NCDC).