Thunderstorms to bring flash flood risk on Saturday

A few days ago I wrote about some intense rain and thunderstorms that are expected during Saturday and just wanted to give an update with the latest information.

At the moment, a slow-moving area of low pressure is sitting to the south west of the UK and is pumping warm, humid air northwards across us. 

As cooler air moves in from the west during Saturday, this will collide with the warm, humid air to produce heavy rain and thunderstorms that will spread northwards through the day.

Whilst there is still some uncertainty in precisely which places will see the most intense downpours, hail, frequent lightning and gusty winds are expected to accompany the rain.

The latest warning information from the Met Office (map below) highlights a large swathe of the UK at risk from heavy rain, with the potential for some places having as much as 40mm of rain in just a few hours.

This intensity of rain has the potential to cause localised flash flooding almost anywhere, although the Environment Agency and Scottish Environment Protection Agency currently have this as a low risk – but still possible nevertheless.

With lightning strikes expected to be frequent, there is also a chance that the transport networks may encounter some problems if overhead power lines are hit.

The heavy rain will also reduce visibility and give plenty of standing water and surface spray on the roads, which is worth bearing in mind if you are travelling on Saturday.

After a lively day of weather on Saturday, Sunday is looking relatively quieter with a mixtures of warm sunny spells and showers, with the showers mainly in the north and west.

Don’t forget, you can get the latest forecast on the Channel 4 Weather website. I’ll also be posting regular updates on Twitter – @liamdutton