Heavy rain and thunderstorms are expected for the North of England and parts of Scotland amid summer storms in the wake of the nation’s heatwave.
The Environment Agency has issued two warnings for expected flooding in Lancaster, where river levels in the area were expected to rise on Tuesday morning.
A further six flood alerts – where flooding is possible – are in place for Birmingham and surrounding districts, along with low-lying land between Shrewsbury in Shropshire, and the Welsh border.
The Met Office has issued a yellow weather warning for thunderstorms across the whole of the UK, stretching from Tuesday to Thursday evening.
Forecasters said an area of heavy rain and storms was expected to move north across parts of Scotland on Tuesday morning, with scattered storms expected for other parts of the country, and very hot weather expected for the South East.
Flood alerts have been issued for 19 locations in Scotland, with one also current for the Vyrnwy catchment area in Wales.
Some heavy showers and thunderstorms are expected for the North of England on Tuesday night, in what will be a warm evening for most parts of the nation.
No injuries were reported, and a spokesman for the fire service said plans were under way to prepare for more storms expected on Tuesday evening.
Temperatures are expected to peak at 33C (91.4F) in London on Tuesday afternoon, while Birmingham could see the mercury rise to 30C (86F).
Wednesday is expected to be very hot again in the south.
Meanwhile, stargazers will have the chance to view the annual Perseid meteor shower this week, should skies clear.
The meteors, mostly no bigger than a grain of sand, burn up as they hit the atmosphere at 36 miles per second (58kps) to produce a shooting stream of light in the sky.
The Environment Agency said it would update its flood warnings and alerts as the situation changes. Those wanting to keep up to date can check on the Gov.uk website, or social media, or through the Floodline service on 0345 988 1188.
The Met Office warned that flash flooding could cause travel disruption and power cuts, but also cautioned about the risks caused by fast flowing or deep floodwater.
The current heatwave is nowhere near the infamous summer of 1976, one of the longest in living memory in the UK, when temperatures reached 32C (89.6F) or higher somewhere in the country for 15 consecutive days.