Recorded global surface temperatures have risen steadily over the past decades (World Meteorological Society). The question will be suspended on 31 December 2025 if still open and the outcome determined using data published by NOAA, expected in January 2026 (NOAA, click "Download" for all data with the site's default settings [Monthly, Global, Land and Ocean, and CSV]). The data for a month as first reported will count, and subsequent revisions to past months are immaterial. As of the launch of this question, the highest reported anomaly was 1.44°C in September 2023.

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