The planet is on the brink of yet another climate milestone. According to the World Meteorological Organization’s latest Global Annual to Decadal Climate Update, there is an 80% chance that at least one year between 2025 and 2029 will surpass 2024 as the hottest on record. The WMO also warns there’s a 70% likelihood the five-year average for 2025–2029 will exceed 1.5°C above pre-industrial levels, with an 86% chance that at least one individual year will top 1.5°C. This is not a declaration that the Paris Agreement target has been breached—because that target hinges on long-term averages—but it is a clear alarm bell that climate risk is escalating rapidly.
As WMO Deputy Secretary-General Ko Barrett put it, “We have just experienced the ten warmest years on record. Unfortunately, this WMO report provides no sign of respite over the coming years” and warns of “growing negative impact on our economies, our daily lives, our ecosystems and our planet” WMO press release.
What the new WMO outlook says about the global heat record 2025–2029
The WMO’s Global Annual to Decadal Climate Update synthesizes predictions from leading climate centers, led by the UK Met Office. The topline findings are stark: each year from 2025 to 2029 is projected to be 1.2°C to 1.9°C warmer than the 1850–1900 baseline; there’s an 80% chance one of those years eclipses the current annual record; and there’s a 70% chance the five-year average itself exceeds 1.5°C WMO publication page.
Even more sobering is the small but “shocking” possibility—about 1%—that one year could briefly exceed 2.0°C above pre-industrial levels before 2030, a probability that “had gone from effectively impossible just a few years ago” to exceptionally unlikely but plausible now, according to contributing scientists summarized by multiple outlets, including the Met Office and media coverage Met Office and The Guardian.
The WMO emphasizes that the Paris Agreement’s 1.5°C and 2.0°C thresholds refer to long-term warming measured over about 20 years. Temporary annual exceedances are expected to occur more frequently as the underlying trend approaches those thresholds. The WMO’s central estimate for the 20‑year average warming over 2015–2034 is around 1.44°C, underscoring how close the world already is to breaching the lower Paris threshold on a sustained basis WMO press release; see also UN News.
Regional climate risk WMO highlights: heat, rainfall, sea ice, and the Arctic
The WMO update warns that the rising global average hides sharper regional swings. For the near term (2025–2029), the outlook points to contrasting patterns that carry serious implications for health, food systems, water security, and infrastructure:
- Arctic amplification will continue. Over the next five extended winters (November–March), the Arctic is projected to warm more than three and a half times the global average, with sea-ice concentration likely to decline further in key basins such as the Barents, Bering, and Okhotsk Seas. This accelerates ocean heating, alters jet streams, and can destabilize weather far beyond the poles, increasing mid-latitude heatwaves and rainfall extremes WMO press release.
- Rainfall extremes diverge by region. The May–September period is expected to be wetter than average across the Sahel, northern Europe, Alaska, and northern Siberia, while the Amazon faces drier-than-average conditions—raising concern about fire risk, ecosystem stress, and carbon sink stability. South Asia, which has trended wetter in recent years, is projected to continue seeing above-average precipitation in the period, though not uniformly across all seasons WMO publication page.
- Heatwaves, droughts, and floods intensify. With each fraction of a degree of additional warming, the WMO expects more frequent and severe heatwaves, heavier downpours, more intense droughts, and compounding risks such as crop failures and infrastructure damage. “Every additional fraction of a degree of warming drives more harmful heatwaves [and] extreme rainfall,” the WMO reiterates, as ocean heat content and sea levels continue to climb WMO press release.
These projections reinforce that “global heat record 2025–2029” is more than a headline—it’s a warning that climate risk is diversifying and intensifying across regions.
What this means for communities and economies
A hotter baseline reshapes risk across sectors. Urban areas face greater night-time heat stress, power demand spikes, and higher ozone pollution days. Rural communities grapple with water scarcity, wildfire smoke, and crop yield volatility. Health services encounter surges in heat-related illnesses and vector-borne diseases. Insurance markets strain under repeated high-loss events, while public budgets face mounting costs for disaster response and resilient infrastructure.
In wetter-than-average zones like the Sahel and northern Europe, intensifying rainfall can overwhelm drainage systems and heighten flood risk, even as seasonal droughts still occur. In drier regions—most notably the Amazon—rainforest degradation and fire incidence can worsen, weakening one of the planet’s critical carbon sinks and feeding back into the global climate system.
“Continued climate monitoring and prediction is essential to provide decision-makers with science-based tools,” the WMO notes, calling for earlier warnings, climate-informed planning, and targeted adaptation for heat, flood, drought, wildfire, and health risks WMO press release.
Paris Agreement reality check: temporary spikes vs. long-term limits
The phrase “breaching 1.5°C” often sparks confusion. The Paris Agreement targets are defined over long-term averages—roughly 20 years—not single years. The WMO underscores that while short-term exceedances are now very likely, the world has not yet definitively crossed the 1.5°C limit in the Paris sense. Still, with the 2015–2034 20‑year mean estimated around 1.44°C, the window to keep long-term warming below 1.5°C is narrow and demands accelerated action WMO press release; UN News.
This year’s COP30 is expected to feature updated Nationally Determined Contributions (NDCs)—the national climate action plans under Paris. Stronger NDCs, earlier coal retirements, rapid deployment of renewables and grid upgrades, and measures to cut methane and other non-CO₂ forcers can still bend the curve. The WMO sums up the stakes plainly: every tenth of a degree avoided reduces climate damage, saves lives, and preserves development gains.
Near-term priorities to manage climate risk WMO identifies
The science calls for a dual track: rapid mitigation to limit long-term warming, and decisive adaptation to manage near-term extremes. Priority steps include scaling heat-health action plans; expanding early warning systems for floods, droughts, and storms; climate-proofing power, water, and transport infrastructure; and safeguarding food systems through climate-resilient crops, irrigation efficiency, and fire management in high-risk biomes like the Amazon.
For businesses and cities, integrating decadal climate outlooks into risk disclosure, capital planning, and insurance strategy is no longer optional. The “climate risk WMO” forecast for the next five years should be treated as a baseline for stress-testing operations, supply chains, and assets.
As Chris Hewitt, WMO Director of Climate Services, emphasized, it’s tempting to fixate on the precise moment that 1.5°C is passed, but “every fraction of a degree matters—it’s really important to keep the warming as low as possible” Climate Change News summary of WMO briefing.
The bottom line
The WMO’s decadal update makes the near-term trajectory unambiguous: the odds overwhelmingly favor a new global heat record between 2025 and 2029, and the five-year average is likely to hover at or above the 1.5°C threshold. Temporary spikes do not equal a Paris Agreement breach, but they foreshadow a world where dangerous extremes become more frequent. The response required is clear—bolder NDCs, accelerated clean energy and methane cuts, and a step-change in adaptation to protect lives and livelihoods now.
“1.5°C is not inevitable,” leading scientists and officials continue to insist. But avoiding it as a long-term average will require decisions in the next few years that shift the entire energy, land-use, and industrial systems onto a more resilient path.
