Transcript for Saharan air layer sweeps across 3,500 miles
We're going to turn now to that massive dust cloud moving in over the U.S. There is concern over asthma and respiratory conditions. ABC's ginger zee with the track. Reporter: The hazy sky today over New Orleans. That's not fog, it's dust. And it's coming from the Sahara in Africa, all the way to the U.S. Look how foggy it is. It's sand. Reporter: Puerto Rico went from those brilliant blue skies to this, when the dust moved in. Barbados, you could barely see the sun. In Mexico, the sky overtaken by brown. It's called the saharan air layer. And it travels over the atlantic ocean every year, but this year, it's covering about 3,500 miles. The most expensive we've seen since the 1907s. For most, that will just mean more brilliant sunrises and sunsets. But for those with breathing issues like asthma, this is a weekend you'll want to watch out. And I should clarify that this is not going to look like a haboob or a classic dust storm, but it is going to move from south to north. You can see the states being impacted there through the weekend. It hangs out 5,000 to 20,000 feet up. All right, ginger. When we come back here
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