After a seemingly endless cycle of floods, downpours and hurricanes in the wettest winter for 250 years, long-suffering Brits have been told to beware: the summer of 2014 is set to be a scorcher.

Professor Armin Bunde of Justus Liebig University, Germany, has calculated that because of the influence of "El Nino" there's a 75% probability that summer 2014 will be the hottest on record due to the very same processes currently wreaking havoc across the world.

Nasa recently released satellite images of storms affecting the US and Europe "arm-in-arm" above the Atlantic. Both storms have their origins thousands of miles away, caused by persistent rainfall in Indonesia and the tropical west Pacific.

Many climatologists believe the reason for the increased frequency of "extreme" weather, including deadly ice storms in the northeastern US and drought in California, is the disruption of the jet stream in the upper atmosphere caused by unusual warming in the Arctic regions. By taking a longer, more meandering path, the jet stream has allowed weather to remain the same – in whatever manifestation – for longer periods.

Although the prospect of an extended spell of sunny weather might be welcomed by waterlogged communities, the news might not be quite as welcome as you might think. In 2003, Europe's worst heatwave for almost 500 years killed an estimated 40,000 people, many of them in France.

Weather experts believe this winter's exceptional weather – which has also included record-breaking heatwaves in Australia – will become normal, as the climate becomes more extreme, leading to more floods, droughts, cold snaps and heatwaves across the globe. Met Office expert Simon Brown predicts average winter rainfall across the UK will be up to 15% worse by 2039, with extreme events also becoming more common.

Labour leader Ed Miliband has warned the UK is "sleep-walking" to disaster if it fails to deal with climate change as soon as possible.