Provisionally the 11th of June 2019 was the coldest day for that particular date since the series started in 1878. The provisional mean maximum of 11.7°C was over 6.6°C below the 1961-1990 LTA. It was that cold! The mean temperature of 10.5°C was only ninth lowest, but then the daily mean series started much earlier in 1772, the reason why it ranked higher was that although the daytime maximum was only 11.7°C the night time minimum was very close to average at 9.2°C.