Cold snap and “first winter sensations”: will it snow in Brittany next week?

Next week, a cold snap is predicted in Brittany. “A cold snap and not a cold wave,” Sébastien Decaux, meteorologist at Météo Bretagne Météo, would like to point out. Often used by misnomer, the cold wave concerns periods of at least three days where temperatures are extremely low, i.e. 5° below seasonal norms. In Brittany, the last cold waves date back to 2018 and 2012. In February 2018, in Rennes, it was -7.2°C in the morning and -0.2°C in the afternoon. Given that we are in a context of global warming, a cold snap, even when it is moderate, is becoming so rare that we perhaps feel it today with a different perception.”

“Between the afternoon of Tuesday November 19 and Friday November 22, it will be cold and there will also be humidity, instability and wind,” warns the meteorologist. We will be treated to an almost winter cocktail with certainly showers, which may be accompanied by sleet, and why not a few snowflakes in certain places, the most favorable of which remains the country of Fougères (35). We may also have some snowflakes in the Monts d'Arrée (29) and on Le Mené (22). Even though we know that we are going to experience a sudden change in weather, the forecasts still need to be refined and we should know more on Monday.”

Frozen roads?

From November 20 to 22, are Breton roads likely to be frozen? “Honestly, I don’t think so,” replies Sébastien Decaux. We are facing a cold and polar air mass, but maritime. Cold air circulates from northern Europe, but it passes over the North Atlantic and the English Channel. It therefore has less icy properties than a continental cold spell. Next week, the lowest temperatures in Brittany should be, in certain places and especially next Thursday, close to 0 to 3°C, at daybreak. During the day, it will often be between 5 and 9°C. And after Friday, we are almost certain that we will have a mild spell with 14 to 15°C during the day.”

“Temperatures will be lower than normal for the season”

“No more showers by the sea”

The meteorologist announces that the region will experience its “first winter sensations” from next Wednesday. “Temperatures will be lower than normal for the season. With a sea temperature, which is still at 14-15°, and cold air above at -30, – 35°C, at around 10,000 m altitude, we will have a big differential between the sea and the high altitude, which will also trigger more showers by the sea than inland. Brittany will, of course, be exposed to the cold, but it will be more severe moving towards the north-east of France.” Does such a week herald a very harsh winter? “For the moment, we know nothing and no one can predict it,” concludes Sébastien Decaux.