The Met Office has issued a thunderstorm warning for the whole of Wales on Sunday marking a change to the current heatwave. Where the storms will hit is notoriously difficult to forecast which is why there is such a large warning area.
The yellow alert is in place from midnight on Saturday until midnight on Sunday and says "heavy showers and thunderstorms" are likely to develop across parts of England and Wales during Sunday with longer spells of thundery rain in places. It adds: "Whilst many areas will see at least some rain most will see only relatively small amounts. However some places could see 30mm in an hour and 60mm in six hours with the potential for frequent lightning, strong winds, and hail. Where this occurs there is likely to be some disruption.
"While there is a high likelihood that thunderstorms will develop over England and Wales there remains a large amount of uncertainty in exactly where these develop. This uncertainty is likely to remain even up to short lead times."
