Britain can expect more tropical-style rainfall as climate change gathers pace, according to research carried out by Newcastle University.
The UK will see more severe floods like those in Boscastle
Scientists said extreme conditions that are likely to lead to flooding have become more common and intense over the last 40 years.
They found that rainstorms have doubled in intensity in places like eastern Scotland and north-east England.
Storms are also becoming more intense in autumn, threatening flood defences.
Dr Hayley Fowler, a member of the research team, said the increased frequency of such downpours will lead to more severe flooding like those experienced in Boscastle in north Cornwall in 2004.
She said: "If the trend continues, which is likely, this suggests we will have an increase in flooding over the coming years which has major implications for flood risk management."
The team predicted that the five million people in the UK who live near to rivers can expected to be flooded with increasing regularity in the future.
Dr Fowler thought water companies should respond by thinking of ways for water storage during extreme weather conditions, which could then be used during drier periods.
"One solution could be to build storage facilities such as small reservoirs close to rivers to catch the excess water following extreme rainfall events.
"This could also help alleviate the potential for flooding as well as solve the water shortage crisis we are likely to experience in the summer months."