Flood alerts have been issued in Newport and Monmouthshire as a downpour of rain is expected following days of blistering heat.

Forecasters are predicting thunder, lightning and flooding as a yellow weather warning comes into force across the UK.

The Met Office has implemented the warning for Scotland and Northern Ireland until 11.59pm on Monday and 11.59pm for all of England and Wales on Tuesday after a change in air pressure led to dramatic showers.

Power cuts and delays and cancellations in trains and buses are predicted, while spray and sudden flooding could lead to difficult driving conditions for motorists.

Greg Dewhurst, a meteorologist at the Met Office, said the week would start off quite humid before cooling down later on.

He told the PA news agency: “We’ll start off initially quite humid, particularly across the south and the east of the UK, with thundery showers and sunny spells, but it will gradually become cooler and fresher as the week goes on.

“First half of the week, we’re looking at some heavy downpours and thunderstorms developing.”

Flood alerts in Newport and Gwent

Two flood alerts have been issued by Natural Resources Wales (NRW) with the rain set to arrive.

Wye Estuary in Monmouthshire

NRW has issued a flood alert for the River Wye, running from Monmouth down to Chepstow.

The previous high tide at Newport reached a level of 7.18 metres at 10pm on Sunday.

Usk Estuary

The Usk Estuary has a flood alert in place today around Newport.

The previous high tide at Newport reached a level of 7.18 metres at 10pm on Sunday.