The Meteorological Records held at Armagh Observatory consist of comprehensive measurements from 1795 - present day. There are also some measurements for the period December 1783 - January 1784 thought to be taken by Hamilton in Cookstown. Included in the collection are a number of barometer readings for the six months from January to June 1788 at Cookstown, Charlesfort, Creggan and Athlone and a book of manuscript observations of meteorological conditions in Glendooen, County Donegal during the years 1846-1868, with many comments on crops, etc. These records are further supplemented by similar records for 1867-1883 and a study of 7- and 11-year cycles in weather records of Glendooen. There is also a collection of letters from 1869-1939 to the observatory concerning meteorological observations at Armagh.
More than 200 years of systematic meteorological observations, believed to be the longest series of homogeneous meteorological data for any site in the UK and Ireland. Maintained on a daily basis.
c.50 volumes of meteorological records 1794 - present day.