The Met Office has issued an amber weather alert for “very heavy rain” and has told Britons to prepare for potential flooding.
The alert, issued just after 7.30pm, is set to come into force at 11pm tonight and last until 8am tomorrow morning.
Residents in County Antrim, County Armagh, and County Down in Northern Ireland are all set to be affected.
According to Britain’s national forecaster: “Very heavy rainfall is expected on Sunday night, leading to the potential for flooding.”
Met Office forecasters advise that spray and flooding is likely and will lead to difficult driving conditions and some road closures.
In addition, “fast flowing or deep floodwater is likely, causing danger to life”.
“Homes and businesses are likely to be flooded, causing damage to some buildings and there is a good chance some communities will be cut off by flooded roads.”
The Met Office also warns: “Delays and some cancellations to train and bus services are likely.
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|Amber Alert issues for Northern Ireland
“Power cuts and loss of other services to some homes and businesses likely.”
Providing further details about the alert, meteorologists warned: “A spell of very heavy rain is expected to affect parts of east and southeast Northern Ireland during Sunday night and at first on Monday morning.
“There remains some uncertainty in the northern extent of the heaviest rain, but some places are likely to have 50-75 mm of rain in a short space of time with a risk of flash flooding.
“Keep yourself and others safe; prepare to avoid travelling by road during potentially dangerous road conditions.
MET OFFICE
|Residents in County Antrim, County Armagh, and County Down in Northern Ireland are all set to be affected
“If you must travel, ensure you watch for possible danger and drive cautiously.
“It is not safe to drive, walk or swim through floodwater, avoid it where possible and if you are affected by fast-flowing or deep water call 999, and wait for help.
“Preparing a flood kit could save you from loss or damage due to flooding to your home or business.
“In your flood kit have: insurance and any other important documents; a torch & spare batteries; a first aid kit, prescription medicines and supplies for looking after your family members or pets; and warm, waterproof clothes, blankets, food and water.”
In addition to the amber alert, four other yellow alerts have currently been issued across large parts of the UK.
A yellow rain alert in Northern Ireland, a yellow thunderstorm warning in Scotland, a yellow rain warning in northern England and the midlands, and a yellow thunderstorm warning affecting Wales and the southwest.