Nasty, nasty Matthew!
As expected, "category 4" hurricane Matthew is relentlessly moving toward Florida. This dude is really bad. He is preparing to move along the East coast of Florida with wind speeds probably higher than 100 miles per hour (mph,) like an enormous broom to clean out the coast line!
Our state is panicking and all local TV stations talk about what to do, evacuate in order to avoid loss of lives, but no one has said that "we are a powerful nation, and we can stop this hurricane to come our way." How powerless the human beings are facing this tiny force of nature. Think about that!
Although Miami may be pretty much out of harm's way, it is quite miserable outdoor, and I dread possible power outages later today and tomorrow, Friday. Florida Power and Light predicts more than a million customers will lose power, and that will be north of Miami, thankfully for me.
So, what are hurricanes? Do you want a refresher course? Below is what I lifted from no less than NASA:
Hurricanes are the most awesome, violent storms on Earth. People call these storms by other names, such as typhoons or cyclones, depending on where they occur. The scientific term for all these storms is tropical cyclone. Only tropical cyclones that form over the Atlantic Ocean or eastern Pacific Ocean are called "hurricanes." Whatever they are called, tropical cyclones all form the same way.
Tropical cyclones are like giant engines that use warm, moist air as fuel. That is why they form only over warm ocean waters near the equator. Do you know that the birth place of our beloved hurricanes is Cape Verde (Cabu Verde,) an archipelago of 10 volcanic islands in the central Atlantic Ocean, located 570 kilometres (350 mi) off the coast of West Africa? The warm, moist air over the ocean rises upward from near the surface. Because this air moves up and away from the surface, there is less air left near the surface. Another way to say the same thing is that the warm air rises, causing an area of lower air pressure below. So the real culprit of our misery is the sun. That's the guy that warms the waters in the Atlantic ocean.
Air from surrounding areas with higher air pressure pushes in to the low pressure area. Then that "new" air becomes warm and moist and rises, too. As the warm air continues to rise, the surrounding air swirls in to take its place. As the warmed, moist air rises and cools off, the water in the air forms clouds. The whole system of clouds and wind spins and grows, fed by the ocean's heat and water evaporating from the surface.
Storms that form north of the equator spin counterclockwise. Storms south of the equator spin clockwise. This difference is because of Earth's rotation on its axis. As the storm system rotates faster and faster, an eye forms in the center. It is very calm and clear in the eye, with very low air pressure. Higher pressure air from above flows down into the eye. When the winds in the rotating storm reach 39 mph, the storm is called a "tropical storm." And when the wind speeds reach 74 mph, the storm is officially a "tropical cyclone," or hurricane. Tropical cyclones usually weaken when they hit land, because they are no longer being "fed" by the energy from the warm ocean waters. However, they often move far inland, dumping many inches of rain and causing lots of wind damage before they die out completely.
Now, you are an expert about the genesis of hurricanes. But how do they move?
Reference.com has a good explanation for you:
Hurricanes are blown around the planet by the prevailing global winds. When a hurricane forms in the Atlantic Ocean, it comes together in a band of winds called the trade winds, which blow east to west in the low latitudes. Once a hurricane approaches land, local weather conditions become a much larger factor in its movement. In particular, high pressure zones can stall or divert a hurricane from its path.
If a hurricane moves above 30 degrees latitude, it may encounter the subtropical high, a relatively stable high pressure air mass over the eastern Caribbean. If it passes around this high pressure center, it encounters the westerlies, a band of winds that blow southwest to northeast. This is why hurricanes that turn northward before they reach the United States often bend back around to the northeast, missing the country entirely.
Similarly, cyclones in other parts of the world are subject to similar wind patterns. Those that form in the eastern Pacific are blown westward by the trade winds toward Asia, or they make it through the Pacific subtropical high and swing northward. Cyclones that form in the southern Pacific move westward as well, but a similar band of westerlies exists to curve errant storms to the southeast. Storms that form in the Indian Ocean exist in a region without strong wind patterns, and therefore are extremely unpredictable in their movements.
I think it is impossible to accurately predict the movements of cyclones. If you want to know more about this, learn about chaos. Human beings will never have enough mathematics, physics and sensors to deal with nature's forces. Should we think about global warming? Not me!
Below is the graphic from the National Hurricane Center, depicting the prediction of hurricane force wind speed from now to Tuesday next week, Oct 11. Where you see the colors darker than orange touching the coast line is where is expected to have wind speeds higher than 74 mph. That's a hurricane!