Drivers have been warnedd to allow extra time for their journeys amid fears the heatwave could have caused a phenomenon known as 'Florida Ice Effect'.

According to experts, the recent heatwaves and hot weather followed by periods of rain can cause a dangerous road surface.

A National Highways spokesman said: “Sudden rainfall onto hot and dry roads can make conditions on the road slippery for drivers because oil and grease build up through the hot weather, so motorists are asked to take extra care.”

Rural roads could be particularly affected due to common use by tractors.

Over time during high temperatures, dirt, grease and oil build up inside of the road surface while it expands in the warmth.

When the weather suddenly changes to cold wet weather, the water enters the road and brings out all of the accumulated dirt to the top of the road surface - known as the Florida Ice Effect.

This creates a slight sludge like layer on the road, removing traction and a dangerous road surface to drive on.