What the winter of 2025-2026 will be like and how temperatures will influence energy prices

In Romania, the first ANM forecast announces the start of winter with temperatures above normal, but this does not exclude the possibility of episodes of frost or snow. The “La Niña” phenomenon could produce surprises in Europe.

The “La Niña” phenomenon could produce surprises in Europe. Archive photo

Experts expect this winter to be warmer (by 1.0 to 1.5 degrees Celsius) than last winter, with lower demand for gas in both Europe and Asia.

“This year, we see a number of risks related to the state of the atmosphere in the Northern Hemisphere, but also that of the Indian Ocean and the Pacific. These interactions between different regions of the planet are called teleconnections”points out Vasilis Pappas, Senior Meteorologist at MET Group, listing some of the teleconnections and atmospheric features that are considered particularly important:

1. Quasi-Biennial Oscillation (QBO): This is a variation of the zonal winds in the lower stratosphere, which gradually propagates downward and has a mean period of about 28 months. This winter, the QBO is in its easterly phase, which suggests an increased likelihood of a weakening of the Atlantic jet stream and more frequent atmospheric blockages – conditions that may favor longer episodes of cold weather in Europe.

2. Indian Ocean Dipole (IOD): This is associated with the sea surface temperature difference between the western and eastern regions of the Indian Ocean. This difference influences the weather in Europe, mainly causing precipitation anomalies in winter. For the coming winter, long-term models point to a negative IOD in early winter (November-December), good news for precipitation in SE Europe.

3. El Niño Southern Oscillation (ENSO): Probably the most well-known of the climate teleconnections, ENSO is associated with temperature variations in the Pacific Ocean and alternates between El Niño, La Niña, or a neutral phase. Currently, and for most of the boreal winter, climatic conditions favor the maintenance of the La Niña phase. This is generally associated with cooler than normal temperatures in East Asia, but has a less direct influence on Europe.

4. The polar vortex: is an extended region of low pressure and cold air that rotates around the Earth's poles, weaker in summer and stronger in winter. The stronger the vortex, the more cold air tends to remain concentrated above the poles (in our case, above the North Pole), without descending to the mid-latitudes. However, this winter started with a weaker polar vortex than usual – raising concerns about frequent cold snaps in Europe.

We expect a slightly milder winter this year

Taking into account all the elements mentioned above, together with the latest sub-seasonal and seasonal forecasts, it is estimated that temperatures on the European continent will be, on average, 0.5 – 1.0°C above the normal values ​​for the winters of 2018–2024, and 1.0 – 1.5°C above the winter averages of 2024–2025.

“While this is the base scenario, there is also an alternative – with a probability of around 20% – which points to a colder winter of around 1.2°C, close to last winter's average temperaturesPappas added.

According to the specialist, if we strictly analyze the relationship between temperature and energy demand (without taking into account energy efficiency measures or structural changes in consumption), “natural gas demand is expected to be lower than last year in both Europe and Asia”. “However, the influence of the La Niña phenomenon on East Asia could bring surprises, through episodes with lower temperatures than anticipatedhe said.

Possible increases in natural gas and electricity prices in December

In Europe, the latest seasonal forecasts indicate an increased likelihood of “Dunkelflaute” phenomena in December – periods when heating demand is high but solar and wind power production is very low. Such situations can generate sudden increases in natural gas and electricity prices, due to the need to supplement thermal production to cover demand that would normally have been met by renewable energy.

One such major event took place on November 6, 2024, when the average electricity price rose to €231/MWh, and in some time slots it even exceeded €800/MWh. Days characterized by high demand and low production from renewable sources also limit the efficiency of battery energy storage systems (BESS), which under normal conditions help reduce price peaks.

“The hydrological situation also plays a key role, especially in South-Eastern Europe, a region heavily dependent on hydropower production. According to the latest forecasts, rainfall above the seasonal average is expected, which would bring significant relief, as hydro reservoirs are currently at their lowest level in seven years.

In conclusion, the interaction between weather-dependent demand in Europe and Asia will be an important factor, as an increase in consumption in Asia could influence the price difference of liquefied natural gas (LNG) between the two regions and, implicitly, redistribution of LNG supplies globally“concludes Pappas.