European heatwave threatens to spur record cooling demand

Western Europe is baking under a heatwave that threatens to drive record cooling demand, just as warming rivers force French nuclear reactors to curb output.

The heatwave is forecast to drive temperatures 5 deg C to 12 deg C above normal in France, Germany, Italy, Spain and southern England, which could raise cooling demand to the highest level in records going back 45 years, according to analysis from Vaisala meteorologist Matthew Dross.

The unusual heat is driven by a dome of high pressure that raises temperatures as it compresses air towards the ground and clears away clouds. Daytime highs could reach above 40 deg C by June 21 in Paris and other regions, according to forecasters in France and weather models from the European Centre for Medium-Range Weather Forecasts.

The most intense heat is forecast for France, where the authorities have issued amber weather alerts across 26 departments, including Paris and much of the central and eastern parts of the country, where grain fields are almost ready for harvest.

Meteo-France warned that the heatwave coincides with the annual Fete de la Musique on June 21, when concerts and street parties are held across the country.

The unusually long-lasting heatwave threatens to curb nuclear output from plants cooled by the Rhone and Garonne rivers, including Saint-Alban, where Electricite de France is preparing to limit generation from June 20. EDF warned that its Blayais facility may also be impacted from June 23.

French nuclear output is closely watched by power markets since the country’s reactor fleet is the backbone of Europe’s electricity system. Restrictions can tighten supplies and lift prices across the region.

To reduce the risk of air-conditioning failures during the heatwave, French transport company SNCF has cancelled more than 70 train services on June 18 and 19, including 14 Paris–Limoges–Toulouse trains, according to France Info.

The heatwave is likely to further dry soils, which have already been depleted by low rainfall in June and a similar heatwave in late May, said Meteo-France. Some areas are approaching record-low moisture levels for the season over the coming days.

The combination of dry vegetation and hot weather with low humidity has raised wildfire risks in France and Spain.

Heatwave conditions are also forecast for Germany and are likely to spread into southern England over the weekend, according to the British Met Office. Temperatures could reach 32 deg C in some areas, with 31 deg C possible in London on June 22 and 23.

Yellow warnings have also been issued in Austria, Belgium, Germany, Italy and the Netherlands. Heat health alerts are in effect for London and much of south-east England and the east Midlands. BLOOMBERG