The WMO decadal climate update says there is an 86% chance that at least one year between 2026 and 2030 will be warmer than 2024, the warmest year on record so far. The World Meteorological Organization (WMO) released the Global Annual to Decadal Climate Update on May 29, 2026, produced by the UK Met Office from forecasts by 13 institutions. We read it through a news report of the release, not the full document. This article summarizes the figures, explains the terms and flags what we could not confirm.
What temperatures does the update expect?
The report projects annual global average temperatures for 2026 to 2030 between 1.3°C and 1.9°C above the 1850 to 1900 average. By our own arithmetic, the middle of that range is 1.6°C. The news report attributes the warming mainly to human-caused greenhouse gas emissions. Global temperatures reached about 1.55°C above that baseline in 2024.
What are the odds on the 1.5°C threshold?
The update gives three probabilities:
- 86% that at least one year in 2026 to 2030 is warmer than 2024
- 91% that at least one year temporarily exceeds 1.5°C
- 75% that the average of the five years exceeds 1.5°C
The news report adds that a temporary exceedance does not by itself mean the long-term goal of the Paris Agreement has been missed, because that goal refers to averages over several decades. The 1.5°C figure in the Paris Agreement is a long-term benchmark and not a single-year limit.
What role does El Niño play?
The update says conditions tend toward El Niño, particularly in 2027 and 2028, and that 2027 may be a strong candidate for a new record. El Niño is a natural pattern of warm Pacific Ocean water that adds heat to the atmosphere. Our report on El Niño 2026 covers the current advisory from NOAA, and record heat in 2026 covers this year’s monthly records.
What does it say about the Arctic?
The Arctic winter, from November to March, is projected to average 2.8°C above the 1991 to 2020 baseline. The news report says that is more than three and a half times the projected global average increase. By our arithmetic, that implies a global increase of about 0.8°C or less over the same baseline. The update also expects continued sea ice declines, especially in the Barents Sea, the Bering Sea and the Sea of Okhotsk. For recent measurements, see the Arctic Report Card 2025 and the Arctic sea ice minimum for 2026.
What are the rainfall patterns?
The update expects wetter conditions in many high-latitude regions in Northern Hemisphere winters, more rain in the tropics and at higher latitudes and less in subtropical regions, especially parts of the Southern Hemisphere. For May to September, it expects wetter conditions in the Sahel, Northern Europe, Alaska and Siberia and drier conditions in parts of the Amazon Basin. Forecast skill for southeastern Europe is relatively low.
How does the range compare with the 2024 record?
The 2024 reading of about 1.55°C sits inside the projected range of 1.3°C to 1.9°C. By our own arithmetic, the top of the range is about 0.35°C above 2024, and the bottom is about 0.25°C below it. That is why the update can give a high chance of a new record in one year while also allowing cooler years in the same period. A range of this width reflects natural variability, such as El Niño and La Niña, on top of the long-term warming trend.
Why combine forecasts from many centers?
The update draws on 13 contributing institutions. Combining forecasts from different groups and models is a common way to reduce dependence on any one method. That is a general explanation and is not quoted from the news report. The report does not describe how the contributions are weighted, so we cannot say how much each group influenced the final probabilities.
What is the difference between a forecast and a projection?
A forecast of the next five years depends on the current state of the oceans and atmosphere, so its skill is higher than that of a long-range projection. A projection for the end of the century depends mainly on future emissions. This distinction is a general one and is not stated in the report we read, but it explains why the update gives specific probabilities for 2026 to 2030.
How to read the numbers
These are probabilities from climate models, not predictions that a given year will reach a given temperature. A 75% chance for the five-year average is a forecast of likelihood, and a 25% chance remains that it will stay below 1.5°C. The updates are issued yearly, so the odds will change as new data arrive. The 2024 figure of about 1.55°C is a single year, while the Paris goal refers to long-term averages.
How does the update connect to other coverage?
The forecast fits with measured records. Our article on 2025 among the three warmest years covers the Copernicus data for last year, and the report on tipping points covers risks that grow with warming.
What should readers watch for next?
Readers can watch for the next annual update, for El Niño development in 2027 and for the monthly bulletins from Copernicus and NOAA. The release does not say how the odds changed from the previous update.
Glossary
- Baseline: a reference period against which temperatures are compared
- Pre-industrial: roughly 1850 to 1900, before large-scale fossil fuel use
- Paris Agreement: a 2015 treaty aiming to limit warming to well below 2°C and pursue 1.5°C
- El Niño: a natural warming of the tropical Pacific that affects global weather
- Decadal prediction: a forecast covering the next several years
These definitions are general explanations and are not quoted from the WMO.
What is not covered here?
We did not read the WMO document, so we cannot report its methods, its uncertainty ranges or the full list of contributing centers. We also leave out other political and economic content in the news report.
Key facts at a glance
- Period covered: 2026 to 2030
- Temperature range: 1.3°C to 1.9°C above 1850 to 1900
- Chance a year beats 2024: 86%
- Chance the five-year average tops 1.5°C: 75%
- Arctic winter: 2.8°C above 1991 to 2020
Frequently asked questions
Who produces the update?
The UK Met Office produces it for the WMO, using forecasts from 13 institutions.
Does 1.5°C in one year break the Paris goal?
Not by itself, because the goal refers to long-term averages.
Which year may set the next record?
The update says 2027 may be a strong candidate.
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