June-August 2026 drought in Western and Central Europe strengthened by human-driven climate change

Contact Authors

• Davide Faranda, IPSL-CNRS, France, davide.faranda@lsce.ipsl.fr

• Marco Zanchi, IPSL-CNRS, France, marco.zanchi@lsce.ipsl.fr

• Tommaso Alberti, INGV, Italy, tommaso.alberti@ingv.it

• Pascal Yiou, IPSL, France, pascal.yiou@lsce.ipsl.fr

• Neven S. Fučkar, University of Oxford, UK, neven.fuckar@ouce.ox.ac.uk

• Haosu Tang, University of Sheffield, UK, haosu.tang@sheffield.ac.uk

• Valerio Lucarini, University of Leicester, UK v.lucarini@leicester.ac.uk

• Marco Chericoni, CMCC Foundation, Italy, marco.chericoni@cmcc.it

Citation

Faranda, D., Zanchi, M., Alberti, T., Yiou, P., Fučkar, N. S., Tang, H., Lucarini, V., & Chericoni, M. (2026). June-August 2026 drought in Western and Central Europe strengthened by human-driven climate change. ClimaMeter, Institut Pierre Simon Laplace, CNRS. https://doi.org/10.5281/zenodo.22808201

Press Summary

• A three-month dry spell as severe as the June-August 2026 European drought is now roughly three times more likely to occur than it was in the past (1950-1987). When similar weather patterns form today, the resulting conditions are significantly drier than they would be in a world without climate change.

• This increased drying is accompanied by temperatures about 2°C higher and roughly 9% less rainfall compared to similar historical events. The most severe drought conditions span from Western Europe, towards the Mediterranean and Central Europe.

• The event was linked to a rare, persistent high-pressure blocking pattern that suppressed rainfall and trapped heat across the region.

• Approximately 90.8 million people and 3 trillion USD (equivalent to about €2.6 trillion) in economic activity were exposed within the drought-hazard area. Of the resulting drought-linked damages, an estimated 10% is attributable to human-driven climate change.

• We attribute the intensification of the drought mainly to human-driven climate change, with natural variability playing only a minor role.

Figure 1. ClimaMeter analysis of the August 2026 European drought (3-month window, June to August 2026). (a, b) circulation (Z500) and temperature anomalies; (c) precipitation during the event and (d) the three-month SPEI (brown = drier, green = wetter); (e, f) present-minus-past changes in circulation and temperature; (g) precipitation changes and (h) SPEI-3 changes; (i) the months in which similar past events occurred; (j) changes at the selected cities. The two dials summarise the attribution (left) and how rare the pattern is (right).

Event Description

Throughout the Northern Hemisphere summer of 2026, much of Europe was gripped by a severe drought that remained acute by the end of August. This continent-scale drought had been building since spring in parts of central and eastern Europe, before shifting westward in early summer and progressively back eastward toward central, eastern and southeastern Europe by August. By mid-August, about half of the European Union (EU) and United Kingdom (UK) territory was in drought, with roughly 9% at the most severe "alert" level. Major rivers ran extraordinarily low: the Seine, Rhine, Danube, Po, Dnieper, and Loire reached record or near-record low levels, disrupting navigation, irrigation and hydropower and nuclear energy generation. Governments introduced water restrictions and shifted freight from rivers to road and rail where possible. Meanwhile more than 500,000 hectares burned across the EU.

In France, the Meteo-France’s summer 2026 assessment shows how abruptly the deficit set in: soil-moisture conditions stayed close to normal until the second half of May, then fell to record-low values as the rainfall ceased and the heat intensified through the season. Record soil dryness was reached in July and August, and the season ranked as the second driest summer in France since 1959, coinciding with the country’s hottest summer since 1900. 

Other national assessments across the continent tell a similar story. In the UK, the Met Office reported the driest July for England since record began in 1836 (receiving only about 10% of the average rainfall). By August the government had declared drought across almost three-quarters of England. In Spain, AEMET recorded the country’s hottest summer on record (about 2.9°C above the 1991 to 2020 average) alongside an exceptional rainfall shortage. The meteorological drought then escalated into a hydrological one across the southern peninsula. In Italy, the Po fell to record-low levels at Cremona, below even the severe 2022 low to roughly a third of the normal flow, prompting Veneto to declare a state of emergency and around a hundred municipalities in Piedmont to ration water. 

The socio-economic consequences of the water deficit have been severe across multiple sectors. Agriculturally, EU yield forecasts for all summer crops fell to 14% below the five-year average. Historically low river levels severely disrupted European supply chains; key commercial arteries such as the Rhine and Danube became at times unnavigable, resulting in higher freight costs, export delays, and forced shifts in transport networks. Energy production was similarly compromised by reduced hydropower capacity and restricted cooling water availability for nuclear facilities in Hungary, Romania, and Bulgaria. Preliminary estimates indicate that the compounding impacts of extreme weather conditions could result in economic losses of €180 billion across the continent. Beyond these economic disruptions, the concurrent extreme heat and dryness exacted a severe public health toll: an estimated 35,000 excess deaths were recorded during the summer 2026 – a figure that is likely an underestimate.

The same combination of heat and dryness primed a catastrophic wildfire season across southwestern Europe, with the drought turning ordinary fire weather into mega-fires. Spain suffered its worst fire year on record, with roughly 186,000 hectares burned by early August. A single blaze near Avila consumed about 50,000 hectares, making it the largest wildfire in the country’s recorded history. With the EU on track for its worst wildfire year on record, a World Weather Attribution study found that the extreme fire-weather conditions behind the Iberian fires have become common because of human-driven climate change. This trend is likely mirrored across other European regions that similarly recorded unprecedented heat and moisture deficits. 

To capture the persistent meteorological drivers behind the drought observed since early summer, the analysis uses a three-month window (June to August, JJA, 2026) ending 31 August. This approach ensures the circulation data reflects the persistent seasonal pattern rather than a single day. The Circulation Anomalies panel (Fig. 1a) shows a strong high-pressure ridge over western and central Europe. Over the same period, Europe experienced up to 4°C temperature anomalies (Fig. 1b) with respect to the climatology, with only localized and very low precipitation over northern Italy (Fig. 1c). The Standardized Precipitation-Evapotranspiration Index (SPEI) panel (Fig. 1d) shows the three-month measure of the accumulated water balance, at strongly negative (drought) values across most of the countries considered.

A Summary of How ClimaMeter Works

ClimaMeter attributes an event by comparing it with its closest historical analogues, that is, past days whose large-scale weather pattern most closely resembles the event. The analogues are split into a past period (1950 to 1987) and a present period (1987 to 2024); the difference between the two sets shows how weather situations like the studied one have changed as the climate warmed. All fields are detrended and deseasonalised before the search, and the significance of the changes is assessed with a 1000-member bootstrap. For the June-August drought analysis, the retained analogues are required to be at least three months apart, so as not to overlap the same season. Finally, we cannot detect the influence of natural climate variability on the event. This means that the changes we see in the event compared to the past may be primarily due to human driven climate change. Similar Past Events (Fig. 1i) cluster in the warm season.

The drought index shown here is SPEI-3, the three-month accumulated difference between precipitation and potential evapotranspiration (estimated from temperature by the Thornthwaite method), standardized against the climatology. Because that method is temperature-based, it tends to give an upper estimate of the warming-driven drying, so the robust quantities are the sign and pattern of the change.

Climate and Data Background for the Analysis

The IPCC Sixth Assessment Report (AR6, Working Group I, Chapter 11) concludes that human-driven warming has increased agricultural and ecological drought in the Mediterranean and parts of western and central Europe, primarily by raising evaporative demand, and that the land dries faster during hot summers through land-atmosphere feedbacks. Working Group I, Chapter 12, identifies the Mediterranean as a regional drought hotspot where the frequency and severity of dry spells increase with additional warming.

Working Group II, Chapter 13 (Europe), highlights water scarcity, reduced river flows, agricultural losses and competition between water uses (irrigation, drinking water, cooling of power plants and river transport) as major and growing risks, with southern and, increasingly, central Europe most affected. Because this pattern has clear analogues in the 1950 to 2024 record and the natural-variability indices differ little between the two periods, we have medium-high confidence in the attribution and classify it as a rare, tending to exceptional, meteorological event.

ClimaMeter Analysis

We analyse how weather patterns similar to the August 2026 European drought have changed between the past (1950 to 1987) and the present (1987 to 2024) over western and central Europe. The event itself was severe and the three-month index (SPEI-3, Fig. 1d) reached about -1.8 standard deviations below normal across Europe. These are also the regions where rivers ran at record lows and agricultural and energy impacts were most acute.

Comparing present with past analogues, Temperature Changes (Fig. 1f) shows warming of about 2°C, while Precipitation Changes (Fig. 1g) for analogous situations falls by about 9%. The SPEI-3 Changes (Fig. 1h) show that the same circulation patterns now produce a water balance about 0.4 units drier than in the past; because SPEI is a standardized index, this shift means a three-month dry spell of this severity is now roughly three times more likely than in the past climate. The extra drying reflects both the modest fall in rainfall and, mainly, the higher evaporative demand of a warmer atmosphere. Its magnitude should be interpreted as an upper estimate, given the temperature-based Thornthwaite potential evapotranspiration used in SPEI, while its sign and geographical pattern are robust. Finally, we cannot detect the influence of natural climate variability on the event. This means that the changes we see in the event compared to the past may be primarily due to human driven climate change. Similar Past Events (Fig. 1i) cluster in the warm season.

Exposure

To estimate the population and economic assets exposed to climate change-influenced conditions, we overlay the ClimaMeter drought-hazard map onto gridded datasets of population density and economic activity using the methodology developed in Faranda et al 2026 (ERL) . The hazard map retains only the grid cells where present-day conditions during events like the studied one are significantly drier than in the historical baseline (1950 to 1987). Onto this area, we overlay gridded population and gridded gross domestic product both at a spatial resolution of about 50 km. 

We then aggregate the population and economic value within the hazard area and categorize them into three severity classes. The categories are based on how unusual the local drought was during the event relative to the 1950-2024 record:

• Moderate: falling between the local 98th and 99th percentiles (representing the most extreme one to two per cent of days);

• Severe: falling between the 99th and 99.5th percentiles (the most extreme half to one per cent); and

• Extreme: exceeding the 99.5th percentile (the rarest and most intense conditions). 

Importantly, these figures measure exposure – the people and assets in harm’s way potentially impacted – not the realized losses.

About 90.8 million people and 3,051 billion USD of economic activity fall within the drought-hazard area. The majority of this exposure is concentrated in the extreme class, with roughly 60.2 million people and 2,042 billion USD in assets subjected to conditions above the local 99.5th percentile. The severe class accounts for an additional  15.5 million people and 461 billion USD, while the moderate class represents 15 million people and 549 billion USD. (Fig. S5).

Impacts and Vulnerability

The methodology for calculating the climate-linked damage share is adapted from Faranda et al. 2026 (QJRMS). In this case, each grid cell represents the geographical spread of the drought. We first calculate how much drier the water balance is today compared to historical analogues, defined as the present-minus-past difference of the SPEI-3 analogue composites. Afterwards, we restrict this estimate to the hazard core, representing the cells where the drought was most severe and where the change is statistically significant. Applying this relative drying to the exposed population and assets splits the local impact into two components that sum to 100 per cent in every affected cell: (1) a baseline share, which the dry spell would have caused anyway, and (2) a climate-change share, the part intensified by  the human-driven warming. Because these results are fractions independent of absolute monetary losses, we report percentages only, while the values below are estimates.  We quantify the uncertainty on this attributable share from the analogue bootstrap. For every grid cell the present-minus-past change (the delta) carries a distribution whose spread is given by the 1000-member bootstrap. We take the 10th and 90th percentiles of that percell delta distribution and recompute the climate-attributable damage for each, bracketing the central estimate. Because the low and high percentiles are applied at every cell at once, the resulting range (reported in brackets) is a conservative envelope of the uncertainty in the attributed drying rather than a strict confidence interval.

Aggregated over the exposed assets, about 10% (10-90th percentile 4 to 16%) of the drought-linked damage is attributable to human-driven climate change (Fig. S6). Crucially, this percentage represents the climate-driven fraction of realized losses, rather than a proportion of the total exposed assets. Because the SPEI drying metric is derived from the temperature-based Thornthwaite evapotranspiration, this share should be interpreted as an upper estimate, though its sign and geographical pattern remain robust.

Conclusion

The 2026 JJA European drought was associated with shifting precipitation deficits across the European continent and amplified by exceptional heat, culminating with very low soil moisture and river flows. From accumulated weather conditions at the end of August 2026, the three-month water balance is now about 0.4 SPEI units drier than in the past (1950 to 1987), which makes a dry spell this severe roughly three times more likely than in the past climate. We attribute this intensification mainly to human-driven climate change, acting mostly through the increased evaporative demand of a warmer atmosphere. About 90.8 million people and 3 trillion USD of economic activity lie within the drought-hazard area, and about 10% of the drought-linked damage is attributable to human-driven climate change.