Italy: Adverse weather forecast to continue across northern and central regions through at least May 17 /update 1

Severe weather is forecast across to continue much of northern and parts of central Italy through at least May 17. Thunderstorms and heavy rainfall have been impacting parts of the region since late May 14 as a weather system passes over northern Italy. Further showers and storms are expected through May 16 before conditions gradually improve May 17. Strong wind gusts, lightning, and hail may accompany storms. Heavy downpours during storms overnight May 14-15 have led to the Lambro River on the eastern outskirts of Milan overflowing, triggering flooding in the Pontelambro district. Several buildings have been flooded and many roads have been blocked by floodwaters. An unconfirmed number of people have been evacuated from the area. Emergency services responded to several other calls for assistance across other parts of Lombardy due to the severe weather. Strong winds, heavy rainfall, and hail also caused flooding and downed trees in Modena in the Emilia-Romagna Region. Further weather-related disruptions are likely across the affected area over the coming hours.

As of May 15, officials have issued the following weather warnings across the country:

• Red heavy rainfall warnings (the highest level on a three-tier scale): Lombardy, Piedmont, and Veneto regions.

• Orange heavy rainfall warnings: Emilia-Romagna, Friuli Venezia Giulia, and Trentino Alto Adige regions.

• Orange thunderstorm warnings: Emilia-Romagna, Lombardy, and Veneto regions.

• Yellow heavy rainfall warnings: Liguria, Tuscany, and Valle d'Aosta regions.

• Yellow thunderstorm warnings: Abruzzo, Friuli Venezia Giulia, Marche, Piedmont, Tuscany, Trentino Alto Adige, and Umbria regions.

Officials will likely update and extend the coverage of weather alerts over the coming days.

Sustained heavy rainfall could trigger flooding in low-lying communities near rivers, streams, and creeks. Urban flooding is also possible in developed areas with easily overwhelmed stormwater drainage systems. Sites 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 rain 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 or landslides impact utility networks.

Floodwaters and debris flows may render some bridges, rail networks, 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. Disruptive weather may cause delays and cancellations at airports in the affected regions. Flooding could block regional rail lines; freight cancellations are possible in areas with heavy rainfall and potential track blockages.

Localized business disruptions may occur in areas impacted by severe weather; some businesses might not operate at full capacity because of damage to facilities, possible evacuations, and some employees' inability to reach work sites.