Scotland faces an increased risk of flooding, damaging winds, transport disruption and rising food costs as a potentially record-breaking El Niño weather pattern gathers strength.
The natural climate event develops in the tropical Pacific but is capable of altering weather patterns and commodity markets thousands of miles away.
The World Meteorological Organization says El Niño is firmly established and is expected to become “very strong” before peaking towards the end of 2026.
There is now an almost 100 per cent probability that it will persist through February 2027, while US government forecasters have placed the chance of a very strong event during the northern hemisphere autumn and winter at more than 90 per cent.
The US Climate Prediction Center has also calculated a 69 per cent chance that the event will exceed the strength of every El Niño recorded since 1950 during the three months between October and December.
Professor Adam Scaife, head of long-range forecasting at the Met Office, said: “I have never seen an El Niño signal this intense in our forecasts.”
El Niño changes the probability of particular weather patterns rather than producing a reliable forecast for an individual country. Conditions over the Atlantic, including the position of the jet stream and the North Atlantic Oscillation, will still determine Scotland’s day-to-day weather.
What weather could Scotland experience?
The clearest signal is for a greater chance of wet, windy and potentially stormy weather during late autumn and the beginning of winter.
The Met Office’s outlook for September, October and November says a warm autumn is more likely than usual and that the period as a whole is somewhat more likely to be wet than dry.
September could still contain relatively warm or settled spells, but forecasting systems show stronger signs of low pressure developing near the UK later in the season.
The latter part of autumn is considered the most likely period for above-average rainfall, while windy weather is expected to become more frequent as winter approaches.
For Scotland, particularly western and northern areas exposed to Atlantic weather systems, that could bring repeated bands of heavy rain and an increased risk of river and surface-water flooding.
Strong winds could also bring fallen trees, damage to buildings and power lines, travel cancellations and coastal impacts. If several systems arrive in close succession, the cumulative effect could be more serious than any individual storm.
The broad period of greatest concern runs from late October into December. Meteorologists cannot yet say when an extreme event will occur, how many named storms will develop or which parts of Scotland will be hit hardest.
El Niño also tends to increase the likelihood of a windy and relatively mild beginning to a UK winter, followed by a greater chance of colder conditions later in the season.
That could leave Scotland facing a change from Atlantic storms and heavy rain during the first half of winter to an increased risk of snow, ice or prolonged cold during January and February. It remains far too early, however, to forecast a repeat of an event such as the Beast from the East.
Pressure on Scotland’s infrastructure
A stormier period could test transport, electricity, water and communications networks across Scotland.
Heavy rain can flood roads and railway lines, overwhelm drainage systems and destabilise slopes beside major transport routes. High winds can force speed restrictions or closures on exposed bridges and cancel rail, air and ferry services.
Network Rail announced on 2 September that it had invested £130 million over the previous two years to strengthen Scotland’s railway against extreme weather. The work forms part of a wider £400 million programme running from 2024 to 2029.
Around £73 million has been spent on earthworks and £37 million on drainage. Projects include improving slopes and drainage on the West Coast Main Line, reducing flood risk on the Highland Main Line and strengthening a hillside above the West Highland Line following a landslide.
David Harkin, Network Rail Scotland’s weather resilience and climate adaptation strategy manager, said: “Our railway was built for a climate that no longer exists.”
Even with that investment, prolonged rainfall could lead to precautionary speed restrictions, line closures and inspections of embankments, bridges and cuttings. Disruption would affect freight as well as passengers, potentially delaying goods moving between ports, distribution centres and supermarkets.
Scotland’s islands are particularly exposed. The Scottish Government’s National Islands Plan acknowledges that extended disruption to ferries and flights can affect deliveries of food, medicine, fuel and other perishable goods.
A sequence of winter storms could therefore create temporary gaps on shop shelves in some island communities even if supplies remained available on the mainland.
Strong winds and flooding can also damage electricity distribution equipment. Power failures can then have consequences for mobile networks, water pumping stations, businesses, care services and households.
The Scottish Government has recognised that transport, power, water and communications networks are closely connected, meaning the failure of one system can produce wider disruption.
How food supplies could be affected
El Niño poses a second risk to Scotland through international food markets. The event changes rainfall across many of the world’s major agricultural regions. It can bring drought to parts of South and Southeast Asia, Australia, southern Africa and northern Brazil, while increasing the risk of destructive rain and flooding elsewhere.
Poor harvests in more than one producing region could affect rice, maize, soybeans, sugar, vegetable oils, coffee and ingredients used in animal feed and processed food.
Drought can also restrict shipping through important waterways, while floods can close roads, railways and ports. The result can be longer delivery times, higher freight and insurance costs and greater competition for available crops.
Scotland would not need to import a product directly from an affected country to feel the consequences. Commodity prices are set internationally, while shortages of animal feed, cooking oil or packaging materials can raise costs throughout the food-manufacturing chain.
There could also be domestic disruption. A very wet Scottish autumn can delay potato and cereal harvesting, damage crops, leave fields inaccessible and increase the cost of drying grain. Flooded roads and cancelled ferries could make it harder for producers to move milk, livestock, seafood and other perishable products.
These pressures do not point to an immediate nationwide food shortage. Larger supermarkets have multiple suppliers, contracts agreed in advance and the ability to substitute products from different countries.
More localised disruption would be possible, particularly on islands and in rural communities dependent on a limited number of transport links.
Could El Niño push up supermarket prices?
Food and non-alcoholic drink prices were 1.3 per cent higher in July than a year earlier, according to the Office for National Statistics. That was the lowest annual rate recorded since September 2021. El Niño threatens to interrupt that improvement.
The World Bank had forecast its global food commodity price index to rise by 2.5 per cent during 2026, but warned that a stronger or longer-lasting El Niño could push prices significantly above that projection. Higher energy and fertiliser costs could amplify the effect.
Historical analysis by the European Central Bank estimated that the transition from a normal to a strong El Niño could raise global food commodity prices by as much as nine per cent.
Its modelling suggested the effect could last for up to two years and peak around 16 months after the start of a strong event, with soybeans, maize and rice among the most exposed commodities.
Wholesale markets could react during autumn and winter as forecasts for crops become clearer, but the largest retail impact may not appear until 2027.
Environment Secretary Dame Angela Eagle has urged households to retain a modest supply of food and water in case extreme weather causes temporary power, water or transport disruption.
The precise severity of the coming autumn and winter remains uncertain. But with El Niño expected to strengthen until the end of the year, the period from late October through the first months of 2027 will be watched closely by forecasters, infrastructure operators, farmers, food manufacturers and retailers.