So I wanted to introduce this blog post with a little personal story:
In another meteorology class I have a case study assignment and I decided to study Hurricane Matthew. While I was home for the Turkey Holiday, and researching for my case study, my parents were being.. well.. parents.. lurking over my shoulder asking what I was up to. When I explained what I was doing they began to ask me a lot of questions which sparked an idea to do an introductory blog to hurricanes. It satisfies this class assignment, sets up my case study, AND it is educational/basic enough that my parents can follow along!
A hurricane is a type of tropical cyclone, which is another term for a low-pressure weather system that generally forms in the tropics. The cyclone is accompanied by organized thunderstorms and strong winds. Each system varies in characteristics and can be more defined than others. I found a great photo with basic description of the parts and their location of a tropical cyclone:
Eye: The eye is known to be the calm central point of the storm. It is not fully understood how/why the eye forms, however, it is suggested that the centrifugal force is a major contributing factor. We know that center points of spinning objects rotate faster than the outside.. but in a tropical cyclone, when we factor in the out-ward force (centrifugal), it suggests that since the force is trying to change the rotating wind speeds to straight, it slows down the sustained speeds.
Eye Wall: This is the barrier between the strong wind and the calm eye. Based on the storm’s intensity, there can be more than one wall (the more walls, the stronger the storm). Thunderstorms form in these regions and are generally accompanied by heavy precipitation.
Spiral Bands: During intense cases, organized bands of thunderstorms can stray away from the eye wall and form in a curved, spiral fashion. They are bursts of precipitation, strong winds, and even tornadoes in catastrophic cases. The intensity of these bursts vary depending on where you are in relation to the eye wall.
Okay, so now that we know the definition of a hurricane and what it looks like, lets look into some specific details that categorize these storms.
Tropical Depression: An organized system of clouds and thunderstorms with a defined surface circulation and maximum sustained winds of 38 mph (33 kt) or less. -So it could be thought of as an average severe storm, amped up a couple of notches-.
Tropical Storm: An organized system of strong thunderstorms with a defined surface circulation and maximum sustained winds of 39-73 mph (34-63 kt). After winds reach 34kts, the storm is given a name. -So the storms are quite severe and may cause moderate to severe flooding but not quite to the point of being categorized as a hurricane. -Compare this to boiling water, bubbles are beginning to form, but not rapidly..
Hurricane: An intense tropical weather system of strong thunderstorms with a well-defined surface circulation and maximum sustained winds of 74 mph (64 kt) or higher. At this point, there is a special system used to classify the intensity and damages the hurricanes may cause.
As you can see in the table provided above, as winds increase, more damage and intense flooding is probable to occur.
Hurricane Season begins on June 1 and ends on November 30, although hurricanes can, and have, occurred outside of this time frame. NOAA’s National Hurricane Center predicts and tracks these massive storm systems. They are number one funded in hurricane research and are in charge of notifying the general public of these storms and the safety precautions necessary to keep safe.
I think hurricanes are very interesting and I cannot wait to learn even more about them, and specifically, more about Hurricane Matthew. If you are interested to learn more about hurricanes, NWS, NOAA, and other weather sites generally have information and storm documentation that can be understood to some extend at all levels. There is a saying “If you fear it, learn about it”. I challenge you to explore/surf the web and educate yourself further on hurricanes. Give me a comment below on something that was not mentioned in this short text.
Written by BreAnna Shore, a student at UND
photo sources: www.researchthetopic.wikispaces.com, www.encyclopedia.com