Attention, 31 departments on orange alert due to freezing rain: what is it? : Current Woman Le MAG

It will be cold, very cold, in the northern half of France. Since Tuesday 16 and until at least Thursday 18 January 2024, an episode of snow is expected in many departments. Due to the arrival of depression Irene, Météo-France placed 31 territories on orange snow-ice alert. According to the meteorological institute, this phenomenon is observed “on an axis going from Upper Normandy to Picardy to Lorraine and Alsace”. In fact, the departments concerned are Aisne, Ardennes, Aube, Calvados, Côte-d’Or, Eure, Eure-et-Loir, Marne, Haute-Marne, Meurthe-et-Moselle, Meuse, Moselle, Nord, Oise, Orne, Pas-de-Calais, Bas-Rhin, Haut-Rhin, Haute-Saône, Paris, Seine- Maritime, Seine-et-Marne, Yvelines, Somme, Vosges, Territoire de Belfort, Essonne, Hauts-de-Seine, Seine-Saint-Denis, Val-de-Marne as well as Val d’Oise. What particularly worries Météo-France? Freezing rain, which should fall in these departments. This phenomenon “generally occurs during a transition period, when a warm spell follows persistent cold weather“ which is the case in mid-January 2024.

Freezing rain, a “very unstable state”

During this change of time, “cold, denser air remains trapped in the first layers of the atmosphere, while the air softens at altitude”describes the institute in a summary note. Scientifically speaking, freezing rain is caused by a state of “supercooling”. This state is made possible when clouds produce snow at altitude which turns into water “when the temperature becomes positive” in his fall. Near the ground, if the air is very cold, “the drops cool” and can thus freeze “almost instantly”. “A very unstable state” according to Météo-France which calls for increased vigilance. Particularly on the main roads of the departments affected by this orange alert. “You must adapt a low speed, double the safety distances and anticipate braking by avoiding slowing down suddenly”warned Jean-Baptiste Jouannic, district manager at Vinci Autoroutes, to the Parisian on January 17, 2024. To deal with this phenomenon, several departments have implemented school transportation restrictions and asked employees to favor teleworking to limit travel.