Flash floods and torrential rain are hitting parts of Wales, bringing an abrupt end to the recent heatwave.
After days of temperatures reaching 30°C and above, forecasters say that fresher conditions are expected to spread across the UK, but with it heavy downpours and ongoing humidity.
Video footage shot on Tuesday afternoon (August 16) shows torrential rain in Port Talbot and Swansea.
WalesOnline photographer John Myers shot footage shortly before 3pm in Talbot Road, Port Talbot, showing the severity of the downpour.
He said: "The rain is coming down so hard... In some parts the flood water is coming up to my knees. Roads have been turned into rivers with many businesses flooded."
Several Yellow thunderstorm warnings have now been issued for the UK by the Met Office, with the potential for frequent lightning, large hail and flash flooding.
They say that we could even see rainfall of at least 50mm in a two or three-hour period in some places across the UK.
Shoppers like Christine Danter saw just how severe the rain was at a supermarket in Merthyr Tydfil, with downpours battering through the shop's roof.
The Swansea branch of bookshop Waterstones also took a battering - with rain pouring through the ceiling of the shop, destroying books.
Showing the damage caused in a video clip, Waterstones Swansea wrote: "With sincere apologies, we are now closed. For reasons."A lovely moment amongst the carnage - loads of customers rushing over to help us save the books (which we had to refuse for safety reasons, but thank you!)"Normal service will (hopefully) be resumed soon."
Met Office Chief Forecaster Dan Suri said: "The change in weather regime will see the heat of the last few days slip away from the south and east, this will be increasingly replaced with more unsettled conditions with heavy showers, thunderstorms and torrential downpours being key hazards over the UK until Wednesday.
“Although not all places will be affected, where thunderstorms occur there is the potential to for very large rainfall totals, but when that heavy rain is falling on extremely dry ground, the risk of flash flooding is much more pronounced.
"With no meaningful rainfall in some southern locations since June, soils in these areas have become baked by the sun turning them into hard almost impenetrable surfaces.
"Any rainfall in these areas won’t be able to soak away and instead it will wash off soils and other hard surfaces, creating flash flooding in some areas.
"This excess water can rapidly inundate some flood-prone areas. Particular areas of cautions are low-lying stretches of road and those areas adjoining sloping fields where water can quickly run off, creating fast-emerging hazards.”