A second batch of Saharan dust is headed for the US.

But forecasters say it's not expected to be as thick as the one that hit the nation last week.

The second dust plume is predicted to reach the Gulf of Mexico this week, affecting a number of southern states.

It can cause poor air quality and irritate people with allergies and asthma.

But on the upside, it can also create spectacular sunsets and sunrises.

Saharan dust reaches the US every year, but this year it's been the worst in decades.