The Met Office has issued yellow weather warnings for heavy rain and thunderstorms, forecast to affect parts of the UK later this week. The warnings cover Wednesday and Thursday, impacting areas including east Wales, the Midlands, northern England, East Anglia, and southern England, including London.
This period is expected to bring one of the most widespread outbreaks of heavy rain across southern and central UK this summer. While beneficial for drought-affected regions, significant rainfall could lead to flash flooding where the ground is too dry to absorb the downpours. Lightning, large hail, and gusty winds are also possible.
Thunderstorms are expected to begin on Wednesday morning, moving northwards from France as warm, humid air sets in. The first yellow weather warning will be active from 03:00 BST on Wednesday until 22:00 BST. Within the warning areas, 20-30mm of rain is possible in less than an hour, with some locations potentially seeing 40-50mm in two to three hours.
The threat of thunderstorms and flash flooding is forecast to continue into Thursday. A second weather warning for thunderstorms will be in effect from 06:00 BST until 22:00 BST. Some storms may become slow-moving across the Midlands, Wales, and Northern England, potentially leading to further flash flooding. Many areas could experience 20-30mm of rain in three hours, with up to 50mm possible in some places, and a small chance of over 75mm in 12 hours over east-facing higher ground.