Heavy rain and flooding could bring a "danger to life" for people in much of Wales on Monday, with up to a month's worth falling within 24 hours, forecasters have warned.
An amber warning that "heavy rain is likely to bring some disruption and probable flooding", issued by the Met Office, is in place for most of South Wales until 9pm on Monday.
The warning states "fast-flowing or deep floodwater is possible", and the conditions could cause a "danger to life".
Yellow rain warnings, meaning disruption is possible, have also come into force for parts of England and Wales until 9pm on Monday.
A yellow warning for rain for the southwest and parts of central Scotland is in place until 9pm on Monday. A further yellow warning covers an area broadly north of Stoke-on-Trent to Carlisle, across northwest England, until the end of Monday.
Monday could be "a significant event for many", and its impact is likely to be greater because the ground is already saturated, the Met Office said.
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Forecasters predict 120mm (4.7in) of rain could fall in the highest ground of the area covered by the amber warning in South Wales, while the wider area can expect 20mm (0.8in) to 40mm (1.6in), with up to 80mm (3.1in) possible across hilly parts.
Communities could become "completely cut off by floodwater, perhaps for several days" and buildings may collapse due to the conditions, the Met Office said.
Around 240mm (9.4in) has already fallen in Wales this month, almost 100mm more than its November average of 162mm (6.4in), according to the Met Office.
England and Wales together have had 143% of the normal rainfall, the agency added.
Records show the quantity of rain forecast on Monday has previously triggered landslides in Wales, a British Geological Survey spokesperson said.
Senior operational Met Office meteorologist Marco Petagna said "all areas have seen above normal rainfall".
Parts of England and Wales "have seen already well-above normal rainfall and another several inches to come", he added.
"Strong south to southwesterly winds will also accompany the heavy rain, with gales possible around coasts and over high ground."
Homes and businesses could be flooded, and there may also be travel disruption and power cuts.
The Met Office said Scotland should see the rain moving away by the end of the day.
"Whilst the rain may ease for a time during the afternoon across southern Scotland, another pulse of heavy rain is possible here during the evening, with all rain eventually clearing by late Monday," it said.
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As of 4.50pm on Monday, there were flood warnings issued for areas across the country.
Natural Resources Wales (NRW) had listed 10 warnings for expected flooding in parts of Wales. The body had also issued 51 alerts for possible flooding.
The Environment Agency had posted six warnings for expected flooding in England - and 81 alerts for possible flooding.
Scotland's Environment Protection Agency (SEPA) had issued eight flood alerts.
(c) Sky News 2025: UK weather: Danger to life warning for parts of UK as 'month's worth of rain' to fall in 24 hour
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