Animated bar chart of September temperatures compared to the 20th-century average from 1850-2023. Blue bars mean cooler-than-average Septembers, and red bars mean warmer-than-average Septembers. The difference from average temperature in Sep 2023 was in a class by itself, shattering previous records for warmth and forcing us to add a new high point to our graph template. Video produced by the Climate.gov team, based on data from NOAA National Centers for Environmental Information. Unless specifically stated otherwise, Climate.gov video productions can be freely republished or re-purposed by others.