‘Possibility of extreme cold snap’ in December, climate experts warn – POLITICO

There is a ‘more likely than usual’ chance that Europe will experience a major cold spell before Christmas, according to a new long-range weather forecast produced by leading international climate authorities.

The warning comes as European countries continue to fill their reservoirs with natural gas, hoping to get through the winter heating season without access to much (or none) natural gas from Russia.

Analysts have said there should be enough gas for a normal winter, but if temperatures drop countries could be forced to ration access to gas, affecting industries and jobs.

The risk of a cold snap this year – most likely in December – remains « very real », Carlo Buontempo, director of the Copernicus Climate Change Service at the European Center for Medium-Range Weather Forecasts (ECMWF) told POLITICO. .

October’s ‘multi-system seasonal forecast’, released on Wednesday, is based on data from the ECMWF and six other national forecasters.

Predicting wintry weather in early fall is fraught with uncertainty, and key factors that could affect conditions — particularly in January and February — are “not yet in play,” Buontempo said. But European governments preparing for the first winter of the energy crisis should nevertheless be alert to the possibility of a cold spell before Christmas that would put further pressure on the continent’s compressed gas supply.

“We are coming out of a hot summer. We know winters are getting milder. So we can be inclined to think that the winter will be mild and we don’t have to worry,” Buontempo said. “That may be the case, but the forecasts we are releasing today and our understanding of how the climate system works lead us to suggest that in fact there is still a chance of an extreme cold spell and , if so, this year this chance – before Christmas – is higher than in a normal year.

A cold snap is believed to be linked to a so-called ‘blocking event’ when persistent high pressure brings ‘abnormal’ easterly winds and colder temperatures over Europe. Currently, climatic conditions indicate that the probability of such an event occurring is slightly higher than usual.

If the current La Niña weather pattern, with colder-than-average sea surface temperatures in the equatorial Pacific, persists into the New Year – which cannot yet be predicted with certainty – that would typically mean a second milder half of winter.

Another key factor in determining weather patterns in January and February – the polar vortex, a ring of high-speed wind surrounding the Arctic – is yet to be established, making any firm predictions about this period impossible.

Buontempo said it was important for European governments to use existing data on climate conditions and likely weather patterns as much as possible – not only to plan for cold spells, but also to predict potential periods of light winds and low rainfall which could impact renewable energy production. .

« We have a huge amount of free and open data available, » Buontempo said. « We have to use it correctly because it has become so strategically important. »

Wednesday’s forecast still contains uncertainties, and energy markets usually pay very close attention to the November long-range forecast because, by then, most of the major factors shaping weather patterns for the second half of winter are in play, a said Buontempo.