The NASA Goddard Institute for Space Studies (GISS) Surface Temperature Analysis (GISTEMP v4) measures global temperature anomalies relative to the 1951–1980 baseline period, with data updated around the middle of each month (NASA GISS). The years 2023 and 2024 set consecutive global temperature records, with 2024 registering an annual anomaly of 1.28°C above the baseline—the warmest year on record (NASA SVS). An unprecedented streak of 15 consecutive monthly records ran from June 2023 through August 2024, with June 2024 setting a new June record. Starting in June 2023, monthly temperatures exceeded previous records by 0.3 to 0.5°C, a pattern that climate scientists described as anomalous even accounting for El Niño effects (NASA Earth Observatory).

Temperature anomalies for any given month can vary substantially based on El Niño/La Niña conditions, volcanic activity, and other factors. NOAA's Climate Prediction Center has indicated La Niña conditions may persist through early 2026, which typically corresponds to slightly lower global temperatures compared to El Niño years. The June 2024 anomaly was approximately 1.26°C above the 1951–1980 baseline, while June 2023 was approximately 1.16°C. Long-term warming trends suggest anomalies will likely remain elevated, though month-to-month variability is significant.

Resolution Criteria:

This question will be resolved using NASA's GISS Surface Temperature Analysis (GISTEMP v4) global-mean monthly data. The question will be resolved based on the global mean temperature anomaly for June 2026, expressed in degrees Celsius relative to the 1951–1980 baseline. Data is typically published around the middle of the following month. If NASA changes its baseline period or methodology prior to publication of June 2026 data, resolution will use whatever methodology is in effect at the time of publication.