This is the terrifying moment a massive dust devil was spotted near a highway in Saudi Arabia.

The brown swirling mixture of air and dust could be seen moving across a dry patch of land in Riyadh on August 2 afternoon.

Filipino worker Jal Ren was driving home when he found the weather phenomenon so he stopped for a while to have a look.

He said: ‘The weather was very hot at that time. I was shocked when I saw the tornado. It was so strong and fast but moved slowly so I thought I could be safe within a distance.’

Dust devils are a type of whirlwind tornado that form when the sun heats a patch of land and the air above becomes warmer and rises quickly.

Cooler air then moves into the low-pressure gap left by the rising warm air. The new drafts of cooler air also heat up, rise and the cycle continues, picking up dust and debris making the spiral visible as it rises skywards.