A hurricane is, as you may know, a complex weather system that simply explained, is a funnel of warm, wet air. It is a non-frontal system whose air has a distinct circular flow. But this is where it gets interesting. Hurricanes that affect the United States actually begin to form when the hot dry air of the Sahara Desert is released into the North Atlantic.
The Sahara Desert is a land mass that is almost the size of continental United States and is the largest "hot" desert in the world. It is also the second-largest desert on the planet and covers 10% of the African continent. Sahara temperatures can swing 30 degrees between day and night in just a few hours. Swirling winds blowing across the desert "carry sand over the Mediterranean, bringing storms into England, and drop sand on the beaches of eastern Florida."
You may remember from your early science classes that hot air rises. As the land mass in Africa grows warmer, the air rises to create the African easterly jet. This column of hot air swirls upward for three miles and then fans out as it races to the continent's western coast. There, it dips toward the ocean and picks up moisture, especially when it reaches Central America and warm waters of the Eastern Pacific. The speed of the wind determines how this system is classified.
When the winds speeds are 39 miles per hour or less, we call it a tropical depression. When the wind reaches speeds of 39 mph to 73 mph, it becomes a tropical storm if its winds are rotating. This is the point where the World Meteorological Association gives it a name. So far, in 2018, there has been one named storm...Alberto. By-the-way, the names are rotated every six years. An official hurricane, a category 1 storm starts when wind speeds exceed 74 mph. Sometimes, tropical storms and hurricanes spend their entire life out over open water and never reach landfall. When a hurricane is large enough to do a lot of damage, the name is retired and is replaced with a new name on the rotating list.
I hope you've found this information interesting. For me, I find it fun to know about weather patterns and to understand how these systems get started.
I invite you back tomorrow for a very special blog on best friends. Where would we be without them, am I right? But, until then, I wish you all