UK weather forecast: Met Office issues flood warnings as heavy rain and thunder sweep country

Parts of UK to have 70mm of rain, causing flooding, travel disruptions and interruptions to power supplies

Heavy rain and thunder is sweeping the UK, bringing the risk of flooding to many areas and heralding the arrival of autumn.

Parts of the UK are set to see 70mm of rain, causing travel disruptions and even interruptions to power supplies from lightning as new weather systems push in from the Atlantic.

The downpour marks an end to unseasonably warm weather, with highs of 27C on Saturday.

Sophie Yeomans, a Met Office meteorologist, told The Independent: “We’ve had a nice week last week and it’s all change really.

“Rain will be coming through in bands. We’ll have bright spells for an hour or two and then frequent rain.”

Up to 70mm is expected to fall in southern Wales and southwest England, while up to 40mm is forecast for the rest of England and Wales.

The remains of Hurricane Humberto – which has left Bermuda and is travelling across the Atlantic – will hit the UK on Monday.

Meteorologist Becky Mitchell said: “It means it’s quite a moist atmosphere, which often brings some heavier rain. The outlook into the start of October does look to stay largely changeable.”

The former hurricane has now become a new low-pressure system.

A Met Office spokesperson said: “At its most powerful Humberto was measured as a category 3 hurricane, but after leaving Bermuda and heading into the cooler waters of the north Atlantic its intensity has waned.

“Its influence will still be felt early next week when the low-pressure system approaches the UK, helping to push the current area of high pressure eastwards, signalling an end to this week’s pleasant conditions.

“The waters of the north Atlantic are too cold to sustain the vast energy demands of a hurricane in full force, so by the time they reach our latitude they have lost their tropical ferocity and have frequently become heavily modified.”

On Sunday evening it will be cloudy with heavy rain and thunder in northern and eastern England and Scotland. Southern and western parts of the country will be mostly dry with a few thundery showers in Wales and southwest England.

On Monday afternoon rain in the southwest of the county will spread northeastwards to Wales, Northern Ireland and western England.

Unstable weather will continue through Tuesday and Wednesday with strong winds and rain. Tuesday will be mostly cloudy with showers and longer spells of rain, some of which will be heavy.