The Met Office has issued a weather warning with heavy rain expected overnight tonight (Sunday 29 September) and strong winds too.
Forecasts suggest that at least two thirds of an inch of rain could fall – or more than 16mm – with winds gusting at more than 40mph.
A “yellow severe weather warning” has been issued for rain across southern England, with a strong wind warning for the area to the west. The “yellow” indicates medium likelihood but low impact.
The Met Office said: “Much of the warning area is likely to see 20mm to 30mm fall over 9 to 12 hours, though some places may see 50mm to 80mm.”
The official forecaster said: “Further heavy rain is likely to cause some travel delays and flooding on Sunday evening and night.
“Some interruption to power supplies and other services is possible (with) spray and flooding on roads probably making journey times longer.”
The Met Office added that bus and train services could be affected with journey times taking longer and the it was likely that some homes and businesses could be flooded.
The forecaster said: “Through Monday, as the area of low pressure clears to the east, further rain will sink south.”
The Environment Agency flood duty manager Katharine Smith said: “Rainfall arriving on Sunday, Monday and Tuesday gives potential for further minor surface water and river flooding impacts across parts of England and Wales.
“Environment Agency teams continue to be out on the ground, supporting local authorities in responding to surface water flooding.
“We urge people to plan their journeys carefully, follow the advice of local emergency services on the roads and not to drive through flood water – it is often deeper than it looks and just 30cm of flowing water is enough to float your car.
“People should check their flood risk, sign up for free flood warnings and keep up to date with the latest situation as well as following @EnvAgency on X for the latest flood updates.”
The Met Office said: “Southern and central parts of England have had a very wet period of weather in the last few days, with recent amber weather warnings preceding flooding and travel disruption for some.
“Some counties in southern and central England have already had more than 250 per cent of their average September rainfall, with the month’s full provisional statistics to be released on (Tuesday) 1 October.
“After the further rain on Monday, which could extend into Tuesday in some eastern and southeastern areas, it should become somewhat drier and brighter more widely around midweek.
“However, there are signals for the potential of further wet and windy weather towards the end of next week.
“There has been some speculation about the impact of Hurricane Isaac on the UK weather next week.
“Hurricane Isaac is expected to transition into an ex-tropical storm through Sunday night and into Monday while over the middle of the Atlantic.
“If it does move towards the UK, it will have significantly weakened and would bring nothing more than a normal autumn spell of rain.”