Residents in northern Italy have been told to get to higher ground amid fears rain-swollen rivers will again burst their banks.
The warning from officials comes after flooding killed at least six people, forced the evacuation of 5,000 and suspended some train services.
The heavy rains and floods also forced Formula One to cancel this weekend’s Emilia-Romagna Grand Prix to not overtax emergency crews already stretched thin in responding to the emergency.
Days of rainstorms stretched across a swath of northern Italy and the Balkans, where “apocalyptic” floods, landslides and evacuations were also reported in Croatia, Bosnia and Slovenia.
The president of Emilia-Romagna, Stefano Bonaccini, said six people were killed and others unaccounted for in flooding that forced the evacuation of thousands of people.
Italian civil protection minister Nello Musemeci called for a new nationwide hydraulic engineering plan to adapt to the impact of increasing incidents of floods and landslides.
At a briefing, he said an average of 200mm of rain had fallen in 36 hours in the region, with some areas registering 500mm in that period.
“If you consider that this region averages 1,000mm of rain in a year, you realise the impact that these rains have had in these hours,” Mr Musemeci said.
Citing the November landslide in Ischia, which killed a dozen people, Mr Musemeci said Italy is increasingly experiencing Africa-style tropical weather, with long periods of drought punctuated by intense rainfall that can’t be absorbed by the soil.
“Nothing will ever be the same again … and what has happened in these hours is evidence of that,” Mr Musemeci said.
“When soil remains dry for a long time, instead of increasing its absorption capacity, it ends up cementing and allowing rainfall to continue flowing over the surface and causing absolutely unimaginable damage.”
The mayor of the city of Cesena, Enzo Lattuca, posted a video on Facebook early on Wednesday to say he continued downpours in the Emilia-Romagna region could flood the Savio river and smaller tributaries for a second day.
He urged residents to move to upper floors of their homes and avoid low-lying areas and riverbanks.
He announced the closure to traffic of some bridges and streets after rivers of mud sloshed through town and into basements and shops.
Mr Museumeci said that 5,000 people had been evacuated, 50,000 were without electricity, and more than 100,000 were without mobile phone or landline use.
The deputy chief of the Civil Protection agency, Titti Postiglione, said rescue operations for those needing emergency evacuations were particularly difficult given so many roads and routes were flooded and phone service interrupted.
Speaking on Sky TG24, she said the affected flood zone covered a broad swath of four provinces which, until the heavy rains, had been parched by a prolonged drought.
Some regional train routes remained suspended on Wednesday around Bologna and Ravenna, with severe delays elsewhere, the Italian state railway said.
Italian prime minister Giorgia Meloni, who was traveling to the G7 meeting in Japan, said the government is monitoring the situation and prepared to approve emergency aid.
In the Balkans, the swollen Una river flooded parts of northern Croatia and northwestern Bosnia, where authorities announced a state of emergency.
The mayor of the town of Bosanska Krupa in Bosnia said hundreds of homes had been flooded.
“We have an apocalypse,” Amin Halitovic told regional N1 network.
“We can no longer count the flooded buildings. It’s never been like this.”
Dozens of landslides were reported in eastern Slovenia, many of which endangered homes and infrastructure.
In Croatia, hundreds of soldiers and rescue teams continued bringing food and other necessities to people in flood-hit areas who have been isolated in their homes.
No casualties have been reported so far.