Since Thursday, swathes of Austria, the Czech Republic, Hungary, Romania and Slovakia have been hit by high winds and unusually fierce rains.

The storm has already caused the death of four people in Romania, and thousands have been evacuated from their homes across the continent.

"We have the first confirmed death by drowning, in the Klodzko region" on the Polish-Czech border, Polish Prime Minister Donald Tusk said Sunday morning.

Tusk was travelling through the southwest of the country, which has been hit hardest by the floods.

Around 1,600 people have been evacuated in Klodzko, and Polish authorities have called in the army to support firefighters on the scene.

On Saturday, Polish authorities shut the Golkowice border crossing with the Czech Republic after a river flooded its banks, as well as closing several roads and halting trains on the line linking the towns of Prudnik and Nysa.

In the nearby village of Glucholazy, Zofia Owsiaka watched with fear as the fast-flowing waters of the swollen Biala river surged past.

"Water is the most powerful force of nature. Everyone is scared," Owsiaka, 65, told AFP.

In the Czech Republic, police reported four people were missing Sunday.

Three were in a car that was swept into a river in the northeastern town of Lipova-Lazne, and another man was missing after being swept away by floods in the southeast.

A dam in the south of the country burst its banks, flooding towns and villages downstream.

- Romanian deaths -

On Saturday, four people died in floods in southeastern Romania, with the bodies found in the worst affected region, Galati in the southeast, where 5,000 homes were damaged.

"We are again facing the effects of climate change, which are increasingly present on the European continent, with dramatic consequences," Romania's President Klaus Iohannis said.

Hundreds of people have been rescued across 19 parts of the country, emergency services said, releasing a video of flooded homes in a village by the Danube river.

"This is a catastrophe of epic proportions," said Emil Dragomir, mayor of Slobozia Conachi, a village in Galati, where he said 700 homes had been flooded.

Parts of northeast Austria have been declared a natural disaster area.

Some areas of the Tyrol were blanketed by up to a metre (three feet) of snow -- an exceptional situation for mid-September, which saw temperatures of up to 30 degrees Celsius (86 Fahrenheit) last week.

Rail services were suspended in the country's east early Sunday and several metro lines were shut down in the capital Vienna, where the Wien river was threatening to overflow its banks, according to the APA news agency.

Emergency services had made nearly 5,000 interventions overnight in the state of Lower Austria, where flooding had trapped many residents in their homes.

Firefighters have intervened around 150 times in Vienna since Friday to clear roads blocked by storm debris and pump water from cellars, local media reported.

Neighbouring Slovakia has declared a state of emergency in the capital, Bratislava.

Heavy rains are expected to continue until at least Monday in the Czech Republic and Poland.