This is why your car has been covered in dustÂ

The layer of muck and dirt has been covering vehicles across the city. 

But what has caused it's sudden appearance? 

Well the layer of dirt is the result of a weather phenomenon known as Saharan Dust. 

It is a mix of sand and dust from the Sahara, the vast desert that covers most of North Africa. 

When strong winds blow across the desert they can whip up dust and sand sending it high into the sky before carrying it from the upper part of the atmosphere and transport it in the direction it is blowing '“ which is sometimes towards the UK. 

Once it is lifted from the ground by strong winds, clouds of dust can reach very high altitudes and be transported worldwide, covering thousands of miles.

In order for the dust to get from up in the sky down to the ground, you need something to wash it out of the sky - rain.

Rain fell across the Portsmouth area yesterday (August 7). 

When the raindrops fall, they collect particles of dust on the way down. Then when the raindrops land on something and eventually evaporate, they leave behind a layer of dust.

Paul Hutcheon, Met Office forecaster, says: '˜We usually see this happen several times a year when big dust storms in the Sahara coincide with southerly winds to bring dust here.'

In certain weather situations, Saharan dust can also affect Air pollution and pollution levels.

Has your car or vehicle been covered by the dust? Let us know in the comments below!