Italy: Adverse weather forecast across much of the country through at least May 26 /update 1

Severe weather is forecast across much of Italy through at least May 26. Thunderstorms and heavy rainfall have been impacting northern parts of the country in recent days, leading to flooding and associated disruptions across parts of the region. Unstable weather conditions are forecast to continue across much of Italy over the coming days, with the worst of the severe weather expected in northeastern regions late May 21, north-central regions and Sardinia May 22, northern regions May 23-24, and south-central regions May 25-26. Strong wind gusts, lightning, and hail may accompany storms. Heavy downpours may lead to flooding in low-lying areas, especially in areas where river levels are already high and the ground is saturated from previous rainfall. Strong winds may cause property damage and power outages.

As of May 21, officials have issued the following weather warnings across the country:

• Orange heavy rainfall and thunderstorm warnings (the middle level on a three-tier scale): Friuli Venezia Giulia, Trentino Alto Adige, and Veneto regions.

• Yellow thunderstorm warnings: Piedmont and Umbria regions.

• Yellow strong wind warnings: Basilicata, Calabria, Emilia-Romagna, Marche, Molise, Puglia, Sardinia, Sicily, and Tuscany 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.