Climate experts warn that extreme rainfall in western Europe is now up to nine times more likely than in pre-industrial times.
A study group comprising European researchers and weather officials analyzed the rains that devastated wide areas of Germany and Belgium in mid-July.
The downpours left more than 200 people dead. Many rivers flooded, destroying and inundating homes.
The group's analysis used existing data suggesting global average temperatures have increased by 1.2 degrees Celsius above pre-industrial levels.
The results show that extreme rainfall is now 1.2 to nine times more likely in western Europe, and that summer downpours can be as much as 19 percent heavier per day.
The group says its findings substantiate a report published in August by the Intergovernmental Panel on Climate Change warning that heat waves and torrential rains are becoming more frequent and intense.
A Dutch scientist from the group says the effects of global warming can be seen around the world. He hopes the findings prompt countries to cut their greenhouse gas emissions and prepare for flooding.