E-Paper
September third-hottest globally on record: EU monitor
September was wetter than average in most parts globally including southwestern and central USA, Alaska, northwestern Mexico and in regions of Brazil, Argentina and Chile
New Delhi: This September was the third-warmest September globally, with an average surface air temperature of 16.11 degrees C, 0.66 degree C above the 1991-2020 average for September, Copernicus Climate Change Service (C3S), the EU monitor, said on Thursday.
This September was the 9th warmest for India in terms of mean temperature and 5th warmest in terms of night temperatures. Over east and northeast India it was the third warmest, as per India Meteorological Department.
This September was 1.47 degrees C warmer than pre-industrial levels or the average for the 1850-1900 period. The 12-month average temperature from October 2024 to September 2025 was 0.63°C above the 1991-2020 average, and 1.51 degrees C above the pre-industrial level, C3S said.
Despite approaching La Nina conditions both land and sea surface temperatures (except for central and eastern equatorial Pacific) remained very high. The global average sea surface temperature (SST) for September 2025 was 20.72 degrees C, the third-highest value on record for the month, 0.20 degree C below the September 2023 record.
“The global temperature in September 2025 was the third warmest on record, nearly as high as in September 2024, less than a tenth of a degree cooler. A year on, the global temperature context remains much the same, with persistently high land and sea surface temperatures reflecting the continuing influence of greenhouse gas accumulation in the atmosphere,” Samantha Burgess, Strategic Lead for Climate, C3S said.
September was wetter than average in most parts globally including southwestern and central USA, Alaska, northwestern Mexico and in regions of Brazil, Argentina and Chile. It was also wetter than average in the Northern Horn of Africa, the southern Arabian Peninsula, Pakistan and northwestern India, central Asia, eastern China. In many of these regions heavy precipitation led to flooding, often associated with the transit of tropical cyclones. Above average rainfall was also recorded over northwestern and central Europe, along the eastern Black Sea coast, and in parts of Italy and coastal regions of Croatia and eastern Spain. In some cases, heavy rainfall caused flooding and associated disruptions.
In India there was 15.3% excess rain over the country in September with 30.7% excess over northwest India; 30.7% deficiency over east and northeast India; 43.7% excess over central India and 11.8% excess over South Peninsula.
In the Arctic, the daily sea ice extent reached its 14th-lowest annual minimum in the satellite record, while the monthly extent ranked 13th lowest, at 12% below average. Regionally, below-average sea ice concentrations were most pronounced north of Svalbard and Franz Josef Land and in the Beaufort Sea.
The National Oceanic and Atmospheric Administration (NOAA) has forecast that La Nina conditions will set in from October. A transition from ENSO-neutral to La Nina is likely in the next couple of months, with a 71% chance of La Nina during October - December 2025. Thereafter, La Nina is favoured but chances decrease to 54% in December 2025 - February 2026, NOAA has said.
La Nina refers to the periodic large-scale cooling of the ocean surface temperatures in the central and eastern equatorial Pacific Ocean, coupled with changes in the tropical atmospheric circulation, including changes in winds, pressure and rainfall patterns. Typically, La Nina brings climate impacts that are the opposite of El Nino, especially in tropical regions.
The World Meteorological Organization (WMO) has said climate change is moderating the influence of El Nino Southern Oscillation. The impacts of naturally occurring climate events such as La Nina and El Nino on climate patterns are taking place in the broader context of human-induced climate change, which is increasing global temperatures, exacerbating extreme weather and climate, and impacting seasonal rainfall and temperature patterns, the WMO said last month.
Thus, January 2025 was the warmest January on record, despite weak La Nina conditions being present since December 2024, when observed sea surface temperature anomalies in the equatorial Pacific crossed the La Nina threshold, the WMO said in March.
