France: Adverse weather forecast to continue across northern regions through at least Nov. 14 /update 2

Adverse weather is forecast to continue to impact parts of northern France through at least Nov. 14. Heavy rainfall since early November has led to rising river levels across the region and triggered flooding in several areas. More than 20 cm (8 inches) of rain has fallen in parts of the region over recent days. Parts of Pas-de-Calais Department have been worst affected; flooding has affected 107 municipalities across the department and schools in around 200 municipalities remain closed as of Nov. 10. Around 35 people were evacuated from affected areas due to rising water levels overnight Nov. 9-10. Around 60 departmental roads have been made impassable by floodwaters and train services have been affected in the area. More showers are forecast across the region Nov. 10, before conditions briefly improve Nov. 11-early Nov. 12. Further showers are forecast in the region from late Nov. 12 through at least Nov. 14. Additional heavy downpours over the coming days will likely exacerbate the flood situation and hamper ongoing relief efforts.

As of Nov. 10, Meteo France has issued the following weather warnings across the affected area:

• Red flood warnings (the highest tier on a three-tier scale): Sections of the Aa, Canche, and Liane rivers in Pas-de-Calais Department in Hauts-de-France Region

• Red rain/flood warnings: Pas-de-Calais Department in Hauts-de-France Region

• Orange flood warnings: Sections of the Hem, Lawe, and Lys rivers in Nord and Pas-de-Calais departments in Hauts-de-France Region

• Orange rain/flood warnings: Nord and Somme departments in Hauts-de-France Region and Seine-Maritime in Normandy Region

• Yellow flood warnings: Sections of the Noireau and Vire rivers in Calvados, Manche, and Orne departments in Normandy Region

• Yellow rain/flood warnings: Calvados, Manche, and Orne departments in Normandy Region

• Yellow thunderstorm warnings: Pas-de-Calais and Somme departments in Hauts-de-France Region and Calvados, Manche, Orne, and Seine-Maritime departments in Normandy Region

• Yellow strong wind warnings: Calvados, Manche, Orne, and Seine-Maritime departments in Normandy Region

Officials could update and possibly extend the coverage of weather alerts over the coming days.

Further sustained heavy rainfall could trigger additional flooding in low-lying communities near rivers, streams, and creeks. Urban flooding is also possible in developed areas with easily overwhelmed or a lack of stormwater drainage systems. Sites located downstream from large reservoirs or rivers may be subject to flash flooding after relatively short periods of intense rainfall. Landslides are possible in hilly or mountainous areas, especially where heavy rainfall has saturated the soil.

Authorities could issue mandatory evacuation orders for flood-prone communities over the coming days. Disruptions to electricity and telecommunications services are possible where significant flooding, landslides, or strong winds impact utility networks.

Floodwaters and debris flows may render some bridges or roadways impassable, impacting overland travel in and around affected areas. Ponding on road surfaces could cause hazardous driving conditions on regional highways. Authorities could temporarily close some low-lying routes that become inundated by floodwaters. Severe weather could also trigger flight delays and cancellations at airports across the affected region.

Localized business disruptions may occur in low-lying areas; some businesses might not operate at full capacity because of flood damage to facilities and some employees' inability to reach work sites.