Nearly half of 2026 is yet to come. This means that any answer to the question posed above is likely to be uncertain. Answering this question with any degree of certainty is also best left to climate scientists, who are better equipped to deal with it. However, a layman’s understanding of the likely answer — this year could easily rank as the second hottest, although being the warmest is not impossible — can help us understand some important things about the climate crisis.
The short summary of the impacts of the climate crisis for a possible answer is as follows. The first thing the potential answer shows is that exceeding the 1.5°C threshold in certain months does not necessarily require an El Niño. The second thing it shows is that breaking this threshold seems relatively easy even on an annual average. The third thing it shows is a corollary to the first two: does year rank matter when no special conditions are needed to break the 1.5°C threshold? The long answer is as follows.
The reason why investigating possible warming scenarios for 2026 is so interesting is because it’s happened before. The past years – 2023, 2024, and 2025 – were the hottest on record. They are ranked second, warmest and third warmest, respectively. Moreover, while only 2025 crossed the 1.5°C threshold – scientists predict catastrophic climate changes if long-term global warming relative to the pre-industrial baseline exceeds this threshold – 2023 and 2025 were very close to this threshold. These two years recorded warming of 1.48°C and 1.47°C, and the average warming in the period 2023-2025 is 1.52°C. In other words, 2026 will confirm whether 1.5°C will continue as the new normal.
It’s not just the past three years that raise the specter of the possibility that 2026 could be the warmest year on record. The first half of 2026 is also very warm. The average temperature for the year to 14 July (latest data available from the ERA5 dataset published by the Copernicus Climate Change Service (C3S)) is 1.45°C warmer than the pre-industrial average. This is the third highest average for this part of the year, after 2024 and 2025.
Summarizing previous trends, one can now ascertain how much warming will be required in the rest of 2026 to break certain thresholds. To maintain third place, 2026 holds for the year until July 14, and the rest of the year needs to average 1.50 degrees Celsius. Likewise, the rest of the year would need to average 1.53°C, 1.56°C, and 1.77°C, respectively, to rank as second warmest year, and cross the 1.5°C threshold at the end of the year, ranking as warmest on record.
Temperatures rising in the 1.50-1.56°C range shouldn’t be difficult at all for the rest of 2026. Here’s why. 2026 reached the 1.50°C threshold in February and recorded highs of 1.47°C and 1.48°C in January and February despite La Nina-like conditions in November and December. The “La Nina” phenomenon is a periodic cooling of the surface of the central-eastern tropical Pacific Ocean, and is expected to lead to a cooling of global temperatures with a time lag ranging from 2 to 4 months. These temperatures, which were still about 1.50°C warmer than normal, suggest that the global warming baseline is hovering on the edge of that threshold for at least the colder months of the year (long-term warming so far has been relatively higher in the colder months in the Northern Hemisphere at the beginning and end of the year than in other months).
If the baseline warming for the coldest months is close to 1.5°C, the rest of the year will have no problem with temperatures rising in the 1.50 to 1.56°C range, because La Niña’s warmer counterpart – El Niño, which drives global temperatures higher – was present in May. In 2023, another recent year when El Nino arrived in May, the average warming from July 15 to December 31 was 1.68 degrees Celsius.
To be sure, the impact of El Niño may appear in global temperatures with the usual two- to four-month lag, but it appears to have already eroded any remaining influence of La Niña conditions. While the months up to April were ranked fourth or fifth warmest, May and June of this year were the second hottest months on record. Clearly, the only question is whether the El Niño effect will be strong enough for the rest of the year to bring average temperatures up to 1.77°C, which is needed to be the warmest year on record. This is a tall order. Only two months in human history have exceeded the 1.77°C threshold: December 2023 and February 2024, which recorded highs of 1.78°C and 1.77°C. However, it may not be impossible. Scientists widely expect the El Nino phenomenon to mature this year into one of the strongest storms on record.
