Saharan dust turns the sky milky white at the annual Ocean Mile Swim in Delray Beach, Florida, United States.
The first round of the mass of dry and dusty air coming from Africa arrived in South Florida on Saturday morning.
The US Environmental Protection Agency set the Air Quality Index in the region at "Moderate" due to the dust.
The agency recommended that people "who suffer from respiratory issues reduce prolonged or heavy outdoor exertion".
The Saharan dust is expected to hang over the region through the weekend.