The Sahara is sending its annual dusting to the Yucatan on Sunday.
All the way from Africa, 7,500 kilometers / 4,660 miles across the Atlantic Ocean, clouds of dust arrive in the Peninsula every summer, generating milky daytime skies and redder sunsets, but also breathing problems.
Sahara Desert sand storms also bring fungi, viruses, bacteria and staphylococci. So some people will be susceptible to eye irritation and asthma attacks, medical professionals warn.
By midweek, the dust is predicted to have spread to Tamaulipas and Veracruz. It will also hit various regions in the southern United States, the Caribbean and Central America. Lightly dusted clouds have already hit Houston.
One good side effect: This swath of dry, dusty air actually helps limit moisture in the atmosphere, hindering the development of tropical storms and hurricanes.