Information on update: The warning area has been expanded eastwards across southern England whilst the validity period has been delayed. Peak rainfall accumulations across Dartmoor have also been increased slightly. Outbreaks of rain are expected to become persistent later on Monday, especially overnight, before gradually clearing during Tuesday, perhaps not clearing the northeast of the warning area til Tuesday evening. Accumulations of 10-20 mm are possible fairly widely, with perhaps as much as 40-60 mm over Dartmoor. Given saturated ground following recent rain, there is a chance this may leading to some flooding and disruption in places. For further details see https://www.metoffice.gov.uk/weather/warnings-and-advice/uk-warnings