The warning is in effect from 9pm on Saturday evening until 6pm on Sunday, covering southern and central England, as well as Wales, with areas as far north as Sheffield and across from Lincolnshire to Tenby being affected.
A new band of “heavy and thundery rain” is expected to move in from the south coast on Saturday, advancing northwards overnight. Some areas could see up to 100mm of rainfall, leading to a risk of localised flooding, power cuts, and travel disruptions.
The Met Office noted that while the intensity of the rainfall will vary, there remains some uncertainty about the exact details. Some locations may receive less than 10mm of rain, while others could see 40-60mm, with isolated areas potentially experiencing 80-100mm.
This comes after heavy rain already hit parts of southern England and Wales on Thursday and Friday. The Met Office warns that the accumulated rainfall could exacerbate potential impacts, particularly in southern areas.
In contrast, regions further north are likely to see dry and sunny spells, though conditions are expected to become cloudier and cooler as the unsettled weather persists into next week.