A big cloud of dust from the Sahara Desert has traveled over the Caribbean. This is the largest event of its kind this year, and it is now moving towards the US. The dust cloud is 2,000 miles long, from Jamaica to Barbados, and 750 miles wide, from the Turks and Caicos Islands to Trinidad and Tobago. Because there is a lot of dust, health warnings have been given. The dusty air can make people sneeze, cough, and have watery eyes. The Saharan Air Layer starts over the Sahara Desert and moves west across the Atlantic from April to October. It is also known to prevent tropical storms from forming during the Atlantic hurricane season. The dust cloud is expected to reach Florida, Louisiana, Alabama, and Mississippi later this week. Last June, a very large Saharan dust cloud, called the "Godzilla dust cloud," covered the Caribbean. This was the biggest event in fifty years.