SAN JUAN, Puerto Rico — A massive cloud of dust from the Sahara Desert blanketed most of the Caribbean on Monday in the biggest event of its kind this year as it heads toward the United States.

However, owing to the wavelength dependence of dust extinction (that is, opacity), the cloud is essentially transparent at infrared wavelengths, enabling otherwise invisible stars behind the cloud ...

ABC30 insider Steven Garcia sent video of a dust devil cloud in Fresno County near West Shaw and North Bryan Avenues Sunday afternoon.