Britain's Met Office has issued a severe weather warning.
A van sinks under a bridge in London. Severe weather warnings have been issued in Britain. Image: Reuters.
The Met Office is warning that the risk of extremely heavy rain, thunder and lightning is greatest in the central and eastern parts of England today, where up to 100mm could fall in a short period.
Other areas at risk include the south west and eastern parts of Wales, where there could be up to 50mm of rain.
The Environment Agency has issued six flood warnings. Parts of Lincolnshire and Yorkshire are most at risk. Flash floods hit North Yorkshire last night.
The downpours started in southern England in the early hours of this morning and are expected to last most of the day.
Met Éireann said the weather in the east and southeast of Ireland will mostly be wet with prolonged spells of rain, which will be heavy and thundery at times.
The will be a brighter start for midlands, west and north, but showers will develop and will be heavy or thundery during the afternoon and evening.