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| Satellite view of a hurricane |
Katrina. Andrew. Hugo. Irene. Floyd.
No, these aren't the names of my children. Nor are they the names of my cats, although I do have five of them. No, they are the names of some particularly newsworthy hurricanes. Even if they are not as severe as these, however, they can still pack quite a punch! Growing up on the shore in North Carolina, I've seen (and driven in!) quite a few of them. While we're still about a month out from hurricane season (usually 1 June-30 Nov in the Atlantic), it still helps to know what these storms are capable of and how to prepare for them.
In case you're not familiar with hurricanes, I'm going to explain them in a two-part posts. In the first part I'm going to give a few facts about the storms, how they form and what they can do. In the second part, I will give you some hints about how to 'brace yourself' if one comes near you.
Technically, the storm I'm calling a hurricane is known in meteorological circles as a cyclone. Like tornadoes, they have very fast winds moving in a circular pattern. Instead of forming over land, however, they form over tropical waters, bringing a *lot* of rain with them! These are the most destructive types of storms Mother Nature has to offer, as anyone whose ever had to clean up after one can tell you! You might have heard it said that hurricanes only occur in the Atlantic. This isn't entirely true. The same type of storm occurs all over the world, but its terminology changes depending on where the storm originates. For example, a cyclonic storm that occurs in the North Atlantic Ocean, Caribbean, Gulf of Mexico or Northeast Pacific ocean is called a hurricane. Storms that occur over the Northwest Pacific Ocean west of the International Dateline are called typhoons. If it occurs near Australia or in the Indian Ocean, it's called a cyclone. For the purposes of this article, I will use the term hurricane.
In addition to strong winds, a hurricane can cause damage with its storm surge-basically, the amount of water it pushes ashore. This can actually be more damaging than the winds in some places because of the sheer amount of flooding it can cause. To give you an idea of what I am talking about, Hurricane Floyd (1999) hit the coast of NC, but caused flooding as far as 130 miles inland!
The longer one of these storms stays over warm water, the stronger it is likely to become. These storms start off as what is called a tropical depression. A tropical depression is a loosely-organized storm winds that hit a maximum of 38 mph. If it grows, it becomes a tropical storm. A tropical storm is organized around central point called an 'eye' with sustained wind speeds of up to 73 mph. Since this is the point where the storm is likely to cause major damage, it is given a 'name'. It used to be that these storms were only named after women (my eighth-grade science teacher had a rather sexist explanation for this) but, since 1978, they are now named after both sexes. The names come from annually-generated lists by the World Meteorological Association.
Hurricanes
are categorized as follows:
- Category 1. Wind speeds 74-95 mph, 3-5 foot storm surge, minimal damage.
- Category 2. Wind speeds 96-110 mph, 6-8 foot storm surge, moderate damage.
- Category 3. Wind speeds 11-130 mph, 9-12 foot storm surge, extensive damage.
- Category 4. Wind speeds 131-155 mph, 13-18 foot storm surger, extreme damage. If you've ever heard of Hazel or Iris, they were Category 4 storms.
- Category 5. Wind speeds 155+ mph, storm surges in excess of 18', catastrophic damage. These are very, very rare. Katrina, Andrew and Hugo were Category 5 storms.
(Continued in next post.)
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