Britain is set for a wetter than average autumn with an increased level of flooding, according to the Met Office.

The chances of a warm and wet autumn are almost two times higher than normal, forecasters said. 

And there is an increased likelihood of windy conditions later in the season – although hosepipe bans are expected to remain in place for months.

Forecasts have indicated that one of the strongest El Niño events on record could develop, while the current El Niño is already at near-record levels.

El Niño occurs when sea-surface temperatures in parts of the tropical Pacific become warmer than average. 

Historically, El Niño events have been associated with warmer, wetter and stormier conditions across the UK and northern Europe during late autumn and early winter which is broadly consistent with the latest seasonal outlook, the Met Office said.

But El Niño is just one of several climate drivers that can influence the UK’s weather.

Tourists shelter with umbrellas from the rain outside Buckingham Palace in London on Tuesday

Grass still appears parched on Hackney Marshes yesterday despite the recent rain in London

The forecaster added that wetter and windier than normal conditions does come with an increased risk of impacts such as flooding.

Met Office chief meteorologist Ian Lisk said: ‘The latest seasonal forecasts suggest an increased likelihood of wetter than average conditions as we move through autumn, which would be consistent with the historical influence of El Niño events.

‘However, El Niño is only one of several factors affecting the UK’s weather and it does not determine exactly what conditions we will experience.

‘While this event may become one of the strongest El Niño events on record, that does not automatically mean more severe impacts for the UK.

‘We will continue to monitor developments closely and update our forecasts as confidence in the outlook evolves.’

Despite this, Anglian Water confirmed this week that a hosepipe ban covering seven million customers in eastern England is likely to remain in place for months.

Grant Tufts, of Anglian Water, told a Norfolk County Council meeting that restrictions could even be in force until winter, with significantly more rain needed to restore reservoir supplies.

Anglian Water supplies parts of Bedfordshire, Buckinghamshire, Cambridgeshire, Essex, Lincolnshire, Norfolk, Northamptonshire and Suffolk.

It comes after Thames Water said last month that the hosepipe ban in London and some surrounding areas is expected to be in place until ‘towards the end of the year’.

Nevil Muncaster, strategic water resources director at the beleaguered utility firm, said there had been ‘huge demand on top of our normal supplies’.

Despite the recent rain, Environment Agency officials said this week that almost three-quarters of England remain in drought – as the country continues to battle its third such event in five years.

While rain has turned the grass green again and it would be ‘understandable’ to think the drought was over, the agency said there was still a very long way to go, with concerns over a number of reservoirs at very low levels.

The warning came after the latest meeting of the National Drought Group of ministers, officials, water companies, farming leaders, anglers and conservation experts, which has focused on the impacts of the prolonged dry conditions on farmers.

A return to steady rain in many areas has provided relief for farmers as they continue to harvest root crops such as potatoes and carrots, though yields are variable.

And the hot weather has exacerbated the current outbreak of bluetongue, a disease spread by midges, which is putting pressure on livestock farmers, while some have had to use winter food stocks for their animals already because of the dry weather, the group heard.

Despite recent rain, the North East and North West of England remain in prolonged dry weather, and the rest of the country is in drought.

All regions continue to experience some degree of water stress after five widespread heatwaves during the hottest summer on record, and with less than two-thirds (64 per cent) of the expected seasonal rainfall.

Officials warn that the summer saw not only low rainfall but an increased demand by the public, agriculture and industry, with water use increasing by as much as 30 per cent on the hottest days.

The south and east of England has received just over half the expected rainfall in the past six months, and autumn and winter rainfall will be important to recharge groundwater reserves, a process that takes months through hardened soils.

Rainfall across August reached 78 per cent of the long-term average nationally, although south-east England received only 54 per cent.

But August 28 to September 3 was the wettest week since early February, according to Environment Agency figures, with ‘rainfall improving river flows, soil moisture deficits and environmental conditions across much of England’.

September has seen a third of its average monthly rainfall to date.