There has been gridlocked traffic on the roads in and around St Albans district, following heavy downpours this morning (Friday). Flood alerts have been issued for Harpenden, Wheathampstead, London Colney, Radlett and Colney Heath.

Highways England has warned on its website that it was called to an incident on the M25 anticlockwise entry slip at junction 21A, following a traffic collision earlier today.

It said that traffic was expected to return to normal in that location by about 4pm today, and lane closures are in place.

A spokeswoman for Herts Police said there was a collision between a Mini and two lorries at J21A at 5.18am.

She said that no one was injured.

However, a complete closure of the affected lanes was put in place at that stage, to allow for the recovery of the Mini and one of the lorries.

Further lane closures were put in place because of localised flooding.

The BBC has reported disruption between J21A for the A405 and J21 for the M1 (Potters Crouch) affecting J25 for the A10, with lane closures and severe delays anti-clockwise between J21A, A405 (St Albans) and J21 M1, because of flooding.

Meanwhile, the Environment Agency (EA) has issued a flood alert for the Upper River Colne and Radlett Brook at Colney Heath, London Colney and Radlett following “recent torrential rain”.

The EA said: “River levels in the Upper River Colne have risen and remain high.

“Further heavy rain is expected to continue throughout the morning across the whole catchment. This is likely to cause river levels to continue to rise which may result in some minor flooding to low lying land, roads and riverside gardens.

“Intense rainfall could also result in some local surface water flooding. We will continue to monitor the situation.”

Flood alerts have also been issued for Harpenden and Wheathampstead – where the River Lea runs through.

The agency said: “Following torrential rain this morning, river levels in the Upper River Lea have risen and remain high. Some further heavy rain is expected today through to mid afternoon.

“This is likely to cause river levels to continue to rise, which may result in some minor flooding to low lying land, roads and riverside gardens. Intense rainfall could also result in some local surface water flooding.”