Fig. 2: Examples of historical weather events which are unsurpassed.

In Durham (UK), the two warmest Junes on record occurred in 1826 and 1846, and are >1.5 °C warmer than any other June in the post-1850 period (a). The grey lines indicate times when only monthly data are available, whereas daily data are available for the period shown by the black line. For Oxford (UK), the wettest month on record remains September 1774, around 15% wetter than any other month (b); recently, September 2024 became the second-wettest on the 250+ year record.