2025 saw the third warmest September on record, a month very close to 1.5 degrees C territory

The chart shows the globe's monthly average temperature per decade from 1940-2019, and then by year for 2020-2025, with the 1.5 degrees Celsius threshold highlighted. Numerous months from mid-2023 through early 2025 reached or exceeded a warming level of 1.5 degrees Celsius above preindustrial temperatures. However, as a long term planetary average, that boundary has not yet been crossed.