Meteorological measurements were started at Armagh Observatory in December 1794, with daily measurements beginning in 1795. They have continued uninterrupted ever since. They represent the longest series of continuous weather records in Ireland, and perhaps the longest in the entire British Isles – the latter is subject to some debate. This is an invaluable resource for climate scientists and historians.
Temperature and pressure were recorded from the start, rainfall has been continuously recorded here since 1836, wet bulb temperatures from 1838, the wind since 1843, and the daily maximum and minimum temperatures from 1844. A Stevenson Screen was installed in 1865, providing a controlled environment for temperature measurements from this date onwards.
Today, manual measurements are still taken at 9am GMT every single day, an unbroken record stretching back to 14 July, 1795. Multiple automatic weather stations have been installed, the first in 1866. Support from the Northern Ireland Department for Communities allowed the latest automatic weather station to be installed by Met Office engineers in 2018, supplementing the daily manual measurements with continuous observations.
A scan of the first weather readings – temperature and pressure – taken at Armagh Observatory from December 1794 onwards. An unbroken record began in July 1795.
Graph illustrating the length of the Armagh climate series for various meteorological parameters