Assessing the Global Climate in October 2023

October Highlights:

• January–October 2023 ranked as the warmest such period on record, and there is a greater than 99% chance that 2023 will be the warmest year in NOAA’s 174-year record.
• For the seventh consecutive month, global ocean surface temperature set a record high. 
  Antarctica had its sixth consecutive month with the lowest sea ice extent on record.
• Fifteen named storms occurred across the globe in October, which was above the 1991–2020 average of 12.

Globally, October 2023 was the warmest October in the 174-year NOAA record. The year-to-date (January–October) global surface temperature ranked as the warmest such period on record. October 2023 marked the fifth consecutive month of record-warm global temperatures. According to NCEI’s Global Annual Temperature Outlook and data through October, there is a greater than 99% probability that 2023 will rank as the warmest year on record.

This monthly summary, developed by scientists at NOAA’s National Centers for Environmental Information, is part of the suite of climate services NOAA provides to government, business, academia and the public to support informed decision-making.

Monthly Global Temperature

The October global surface temperature was 2.41°F (1.34°C) above the 20th-century average of 57.1°F (14.0°C) and ranks as the warmest October in NOAA’s 174-year record. This was 0.43°F (0.24°C) above the previous record from October 2015. October 2023 marked the 47th consecutive October and the 536th consecutive month with temperatures above the 20th-century average. The past 10 Octobers (2014–2023) have been the warmest Octobers on record.

South America and Asia had their warmest Octobers on record. North America, Africa and Europe each had their second-warmest Octobers, while October in Oceania ranked 15th warmest on record. October in the Arctic ranked fifth warmest while the Antarctic region had its sixth-coldest October on record. For the seventh consecutive month, global ocean surface temperature set a record high.

Temperatures were above average throughout most of North America, South America, western, southern and eastern Europe, Africa, Asia, Oceania and the Arctic. Parts of Central and South America, Africa, Europe, northeastern North America and central Asia experienced record-warm temperatures this month. Sea surface temperatures were above average across much of the northern, western and southwestern Pacific as well as the northern Atlantic and the Indian Oceans. Record-warm temperatures covered nearly 11% of the world’s surface this October, which was the highest percentage for October since the start of records in 1951.

Temperatures were near to cooler than average across parts of Antarctica, southern South America, north-central North America, the Nordic countries, Greenland and northern Oceania. Sea surface temperatures were near to below average over parts of the southeastern Pacific Ocean, the eastern Indian Ocean and the southern Atlantic Ocean. Less than 1% of the world’s surface had a record-cold October.

Snow Cover and Sea Ice Extent

October 2023 set a record for the lowest global October sea ice extent on record. This primarily resulted from record-low sea ice extent in the Antarctic, which saw its sixth consecutive month with the lowest sea ice extent on record. Globally, October 2023 sea ice extent was 380,000 square miles less than the previous record low from October 2016.

The Arctic sea ice extent for October 2023 ranked as the seventh smallest in the satellite record at 2.46 million square miles, or 430,000 square miles below the 1991–2020 average. October sea ice extent in the Antarctic ranked lowest on record at 6.25 million square miles, which was 780,000 square miles below the 1991–2020 average. Eight of the first 10 months in 2023 have seen Antarctic sea ice extent at record-breaking low levels.

According to data from NOAA and analysis by the Rutgers Global Snow Lab, the Northern Hemisphere snow cover extent during October was 170,000 square miles below the 1991–2020 average. This ranks as a near-average Northern Hemisphere snow cover extent for October. Extent was slightly below average in both North America and Eurasia.

Global Precipitation

In general, rainfall anomaly patterns followed the current El Niño and Indian Ocean Dipole patterns, ranging from floods in eastern Africa to drought in Central and South America. Above-average precipitation in Europe somewhat alleviated drought conditions in the region, with floods affecting Italy and the United Kingdom. The mean global precipitation for this October set the record for this month with a value 6% above the long-term average, and the intensity of the global Intertropical Convergence Zone also set a record for October due to global warming and current El Niño conditions.

Global Tropical Cyclones

Across the globe in October, 15 named storms occurred, which was above the 1991–2020 average of 12. Nine of those reached tropical cyclone strength (≥74 mph), and seven reached major tropical cyclone strength (≥111 mph). Super Typhoon Bolaven in the West Pacific and Hurricane Otis in the East Pacific both reached Category 5 strength (≥157 mph). The global accumulated cyclone energy, which is an integrated metric of the strength, frequency, and duration of tropical storms, was about 34% above the 1991-2020 average for October.

For a more complete summary of climate conditions and events, see our October 2023 Global Climate Report or explore our Climate at a Glance Global Time Series.