UK weather maps show where 50 mm of rain could fall on WednesdayHeavy rain, thunderstorms and the risk of localised flooding are set to affect parts of the UK on Wednesday. In some places, rainfall totals could reach as much as 50 mm over the course of several hours. The heaviest rainfall on Wednesday is expected across north-eastern Scotland, where some locations could see up to 50 mm of rain within a few hours. Northern areas will be noticeably cooler, with highs closer to 20°C. By Friday, however, another weather system is expected to approach north-western parts of the country, bringing increasing cloud and outbreaks of rain to western Scotland and Northern Ireland.