An amber warning for heavy rain strong enough to cause landslides has been issued for a large swathes of South Wales.
Forecasters predict a whole month’s worth of rain is set to fall across the area in the space of just 24 hours.
The ‘be prepared’ warning is in place until 11.59pm on Monday night and advises there is a risk of ‘fast flowing or deep floodwater’ which ‘could cause a danger to life’.
Some 120mm of rain could fall on high ground, sufficient to trigger landslides, a spokesperson for the British Geological Survey said.
The Met Office warned that the impact will be felt more greatly in what it termed a ‘significant event for many’ as the ground is already saturated from previous rainfall.
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Wales has so far experienced 240mm of rain this month, far more than its average for November of 162mm.
Elsewhere, a yellow rain warning is set to come into effect overnight for the rest of Wales as well as south west and north west England and will stay in place for many until Tuesday.
Senior operational Met Office meteorologist Marco Petagna suggested that the agency would not issue further warnings for beyond tomorrow in order to not ‘distract’ from tomorrow’s expected severe weather.
He said: ‘All areas have seen above normal rainfall, Scotland and Northern Ireland are less of an issue of tomorrow, away from south-west of Scotland.
‘It’s mostly parts of England and Wales – many areas have seen already well-above normal rainfall and another several inches to come.’
He added that the outlook for Tuesday and Wednesday was looking brighter with less heavy showers.
A total of 38 alerts for flooding have been issued by Natural Resources Wales.
Duty tactical manager Richard Preece urged people to stay alert for possible floods, including by avoiding swelling riverbanks or driving through floodwater.
He said: ‘With some rivers already swollen and the ground saturated, we expect to see a number of flood alerts and warnings issued.
‘We’re urging people to be vigilant and to make preparations for potential flooding now.
‘We also want to remind people to keep away from swollen riverbanks and not to drive or walk through flood waters as you don’t know what lies beneath.’
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