Outbreaks of heavy rain will affect parts of south Wales at times on Monday. Please be aware that this may lead to standing water and spray on roads, making for tricky travel conditions. A moist southerly airstream will bring periods of rain through Monday, producing locally 20 mm in 3 to 4 hours, and with overall totals perhaps around 40 mm, especially on hills.
At this stage there remains some uncertainty as to how persistent and heavy the rain will be, so watch out for possible updates to this warning. The public is advised to take extra care, further information and advice can be found here: http://www.metoffice.gov.uk/public/weather/warnings/