Thunderstorms and heavy showers are expected to develop during Thursday morning and through the afternoon. These could produce torrential downpours in a few places with as much as 25-35 mm of rain falling within an hour and perhaps 60 mm within 2 hours. Frequent lightning and hail will be additional hazards. Storms will tend to become more confined to the south and east of the warning area later in the afternoon before dying out during the evening. For further details see https://www.metoffice.gov.uk/weather/warnings-and-advice/uk-warnings