UK Weather Warnings Issued as 50mm Rain Brings Thunderstorms and Flash Flood Risk

Heavy rain and thunderstorms are set to bring a risk of flash flooding across parts of the UK as low pressure moves in following weeks of hot and dry weather.

A Met Office yellow thunderstorm warning remains in force across northern England and north Wales until 10:00am on Thursday. Forecasters say 15 to 20mm of rain could fall within an hour in some areas, with 30 to 50mm possible over six hours, alongside lightning and hail.

The downpours follow an unusually dry summer, with July 2026 recorded as the driest July on record for England and Wales. The Environment Agency has declared 71.3% of England to be in drought, while authorities have warned that sustained rainfall will be needed to improve water supplies.

Thunderstorms Bring Flooding Risk

Low pressure moving eastwards has replaced the high-pressure system that dominated much of the summer. Unstable air beneath the low is allowing thunderstorms to develop, with heavy showers expected to move south and east during Thursday.

Northern England and north Wales are expected to see the heaviest downpours on Thursday morning. Showers will then spread into other parts of Wales, the Midlands, East Anglia and southern England, where some areas could see further heavy and thundery rain.

The prolonged dry spell has also left some ground hard and compacted, increasing the risk of surface water and flash flooding when heavy rain arrives. Further weather warnings could be issued as unsettled conditions continue through Thursday and into Friday.

Drivers Warned About Slippery Roads

The return of wet weather is also expected to create difficult driving conditions after the prolonged dry period.

RAC road safety spokesperson Rod Dennis said oil, fuel and rubber deposits accumulated on roads during the dry weather could mix with rainfall and increase the risk of skidding. He also warned that heavier rain could leave motorists facing flooded roads.

Drivers have been advised to reduce their speed and leave additional space between vehicles as conditions change.

Drought Persists as Temperatures Fall

Although the rainfall will bring some relief from the dry conditions, it is not expected to end the wider drought immediately.

The BBC's weather service said sustained rainfall would be needed to replenish water stocks, with the full impact unlikely to become clear until later in the year or during winter. More than 20 million people are currently affected by hosepipe restrictions in the UK, while water companies have said prolonged rainfall will be needed before restrictions can be lifted.

Conditions have varied considerably across the UK. Aultbea in the Scottish Highlands has recorded 389.6mm of rain so far this summer, more than one and a half times its seasonal average and just 10.2mm short of its wettest summer on record.

Temperatures are also expected to fall as northerly winds develop. Thursday's daytime temperatures are forecast to reach between 13C and 23C, making it the first day since 29 June when temperatures are expected to remain below 25C across the UK.

Friday is expected to be cooler, with temperatures widely falling below the August average. Overnight temperatures will also drop into single figures, with parts of Scotland and northern England potentially reaching lows of 3C or 4C.

High pressure is expected to build over the weekend, bringing drier conditions and some sunshine, although sustained rainfall will still be needed to ease the UK's wider water shortages.