Weather alert: Episode of strong winds, snow in the Alps

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From Monday February 21 at 12:00 p.m. to Monday February 21 at 6:00 p.m.

Situation

After crossing the northern part of France, Storm Franklin evacuated towards Germany and Denmark. The winds blew between 100 and 140 km / h in gusts from the coasts of the Channel to the Hauts de France with up to 171 km / h at Cap Gris-Nez. The regions north of the Seine suffered maximum gusts between 90 and 110 km / h. This Monday, behind the depression, the north-westerly flow is accelerating as it arrives in the Mediterranean, giving an episode of strong mistral and tramontane winds and a violent libeccio over Corsica.

In the Northern Alps, the wet northwesterly flow brings sustained snowfall. Higher up, the strong wind brings blizzard conditions with significant wind chill.

Observation

?15 hours, the storm continues in Corsica with a maximum gust measured in Ajaccio (Corse-du-Sud) of 123 km / h and 172 km / h in Île-Rousse (Haute-Corse). The mistral still blows on average between 90 and 100 km / h in PACA. A maximum gust of 92 km / h was recorded in Antibes, 105 km / h in Martigues (Bouches-du-Rhône) and in Castellet (Var). The tramontane does not strain with a gust of 97 km / h in Montpellier (Hérault) and Perpignan (Pyrénées-Orientales) and 100 km / h Leucate (Aude).

At 12 o’clock, the wind continues to blow violently in Upper Corsica with 140 km / h in Cagnano, 141 km / h in Cape Corsica, 145 km / h in Cape Sagro and 147 km / h on the red island. In Corse-du-Sud there are 113 km / h in Porto-Vecchio and up to 144 km / h in Conca. In the PACA region, the wind blows at 119 km / h in the Dramont in the Var; the tramontane strengthens on the Roussillon with 103 km / h in Formiguères and 130 km / h in Cap Béar.

At 9 o’clock, it is in Haute-Corse that the wind gusts are most violent this morning with 123 km / h on the red island (2B), 146 km / h at Cape Sagro (2B), 1458 km / h in Maniccia (2B), 150 km / h at Cape Corsica and 162 km / h at Cagnano (2B). In southern Corsica, 114 km / h are observed at Cape Pertusato. In the Var, the Dramont observed a gust at 129 km / h. The wind remains strong on the coasts of the English Channel with 111 km / h in Fécamp, 107 km / h in Brignogan and 102 km / h in Saint-Cast-le-Guildo (Côte d’Armor). In the Alps, the wind is strong at altitude with 108 km / h in Bonneval (73) and 118 km / h in La Masse (73).

In the night, the strongest winds were observed near the English Channel at 171 km/h at Cape Gris Nez (62), 141 km/h at Fécamp (76) and 140 km/h at Barneville-Carteret (50), 127 km /h in Boulogne-sur-mer (62), 124 km/h in Saint-Vaast-la-Hougue (50) and 117 km/h in Calais (62). Inland, the wind reached 135 km / h in Bernaville (60), 128 km / h in Steenvoorde (59), 122 km / h in Cerisy la Salle (50), 120 m / h in Fontaines-les-Vervins (02), 116 km/h in Saint-Arnoult (60), 111 km/h in Arras (62) and Lillers (62), 109 km/h in Rouvroy-en-Santerre (80), 105 km/h in Cambrai (62) and Courouvre (55) and 100 km/h in Muids (27) and Chouilly (51) for the most remarkable values.

Evolution

Here is the chronology and the characteristics of this degradation

This Monday afternoon, as storm squalls pass, gusts can still reach 100-110 km / h between Normandy and Hauts-de-France and 80-90 km / h in the land north of the Seine. In the south, the mistral and the tramontane blow strongly, up to 90-110 km/h in the Roussillon plain, lower Rhône valley and in Provence, with peaks at 120-130 km/h on the Corbières and the capes and coasts exposed by the sea. In Corsica, the wind continues to blow in a storm, with peaks of more than 150 km/h on exposed capes and coasts as well as in the mountains.

From Monday evening, the wind will weaken thanks to the strengthening and approaching of the Azores anticyclone.

Snowstorm in the Alps

At the same time, precipitation is blocked by orographic effect on the north of the Alps until Monday evening. Nearly 30 to 50 cm of fresh snow is expected above 1300 meters on the Savoies to the center of Isère and 20 to 40 cm on the Jura around 1200 meters.

Precautionary advice

Watch out for strong and sudden gusts in showers and sleet! Also beware of the risk of falling branches! You also have to be very vigilant along the coast with a significant risk of submersion because of the still high tide coefficients if you are by the sea! Finally, access to the ski resorts north of the Alps is very complicated this Monday because of the heavy snowfall from 900 meters above sea level.

In summary

This episode of bad weather is responsible for a lasting episode of strong winds with stormy gusts over the northern and southeastern regions of the country, as well as a violent storm over northern Corsica.

Even if this episode of strong winds is a notch below that of Friday, it is more durable and should not be neglected in a context where trees and infrastructure may have been weakened by storm Eunice. Finally, it should be noted that this episode of strong winds affects more regions than the strong gale on Friday, since the south-east of France is also affected.

List of departments concerned

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