Archive for the ‘Homosassa flood potential’ Category
Enlarge images in this posting with left clicks.
ILLUSTRATION B – map of Citrus County showing locations of the Gulf Coastal Lowlands which are subject to storm surges, the sandy Brooksville Ridge occupying more than one-third of the area, and the Tsala Apopka Plain containing the majority of the county’s fresh water lakes –
– TWO INDEPENDENT LEFT CLICKS ENLARGE THE IMAGE ABOVE TO THE FULLEST –
I Am Very Happy Living In Citrus County.
Of course, being retired, being a nature-lover and being relatively healthy helps. All locations have pros and cons but with respect to the latter I have yet to regret the move with my extended family 9 years ago. We had experienced hurricanes and tropical storms through the years. Our house was a total loss in 1992’s category 5 hurricane Andrew; it was at ground zero in Homestead which is located 27.6 miles (as the crow flies) southwest of Miami. The house belonging to my wife’s folks, less than a mile away, had extensive damage. What a terrible mess was caused by the only hurricane to make landfall upon the U.S.A. that season. But when we moved to Citrus County 13 years later we were conscious of the fact that by leaving South Florida we had NOT left “hurricane country.” I felt that Citrus County would be safer in that respect but certainly not a hurricane-proof location. It didn’t take long for me to meet people who felt that there was something special about Citrus and other nearby counties that made a serious hurricane event almost inconceivable.
Complacency is a real problem in hurricane country. I don’t claim to be an expert on complacency but there have been times in my life where I might have contracted the disorder I call “terminal uniqueness.” Therefore, I am acquainted with denial, ignorance, procrastination, irresponsibility, and “living in a dream world” because I’ve been there; for all I know, I’m there still. I believe that every time I point a finger at someone, three are pointing back at me and this is written in that spirit. Thus, I’m not trying to indict anyone here; I’m just trying to state what appears to me to be true.
As I see it – Citrus County, as a whole, though probably not the “geographical poster child” for complacency when it comes to hurricanes and tropical storms, seems to be after the title – in spite of its experience with “The Florida Four in 2004” (see illustration C below). I’m not speaking of those who vigorously engage in emergency planning and increasing awareness in the community. And of course I’m not speaking to residents reading this who have engaged in effective advanced planning and preparation. No, I’m speaking of the average Jack and/or Jill occupying a dwelling in Citrus County; I acknowledge that there are plenty of exceptions. To be sure – this is not a problem exclusive to Citrus County. I believe it’s prevalent in all or nearly all parts of the country susceptible to tropical cyclonic weather. Please click on this graphic below for enlargement.
The four 2004 storm tracks above are dated for your convenience. For example: Tropical storm Bonnie’s track runs from August 3rd to August 14.
NOTE: For an infrared satellite loop of the majority of the 2004 season, click on the first link below. Date and time indicators appear along the bottom margin. Then for an animated loop which is easier to interpret click on the second link.
I moved to Florida in 1956 during my high school junior year and I don’t remember a time since when I have not been conscious of the potential for tropical weather to wreak havoc upon lives and property and I have always tried to be prepared. If you were to have simply driven by my house you could have observed elements of hurricane preparedness. That is still true today. It is a high priority item in my family. I have been an active advocate of hurricane awareness and preparation for many years. If anything, I hope that illustrations in this weblog posting will increase awareness at least among the few who see it. So let me call your attention to the illustration below. Most residents who see such illustrations are, at the very least, surprised. Naturally some point out that this covers a long period of time. But really, is 161 years a long time in the whole scheme of things? My point in showing this is: TROPICAL CYCLONES ARE A REALITY IN CITRUS COUNTY. Also, please be aware of the fact that the plot lines show the paths of the centers of storms and that the storms have a width that is not apparent here. The center of a storm does not have to come within just a few miles for it to be of great concern; the center can be many miles away.
Even before leaving Homestead for good in 2005 – while visiting Citrus County I detected the existence of a notion of immunity to any sort of serious tropical cyclonic weather (e.g. hurricanes, tropical storms). Though I have no scientific evidence to back this – I classify the “no-need-to-be-concerned” feeling as widespread among the Citrus County population. In fact, sometimes “low-to-no” hurricane probability has been drastically overstated here (I’ve heard it and I’ve heard about it). It seems that “The Florida Four in 2004 ” did very little to squelch the delusion. Still – I would have expected that particular season to have provided a huge “wake up call.”
NOTE: The “official” Florida Four in 2004 includes hurricane Charley which struck Punta Gorda on August 13 and later moved through South Carolina. It does not include tropical storm Bonnie.
Just a few weeks ago I overheard a hostess at a popular restaurant in adjacent Marion County telling a booth full of patrons, “We just don’t get hurricanes here.” Recently a friend of mine suggested that there was something about our county’s geography, specifically the Brooksville Ridge, that prevented hurricane visits. That reminded me of Muncie, Indiana where I used to live; it is alleged to be immune from tornadoes because of a particular bend in the river flowing through it. Also, a protective blessing from an Indian chief has been cited.
“The Florida Four in 2004” did not produce the extent of damage or flooding that raised eyebrows all over the nation and, for now, a sense of security from lethal storms seems to cling on. This is not a prediction nor is it my wish, but I do fear that a hurricane coming through this area has the potential to surprise a lot of people and make them wonder what they were thinking. And such an event could be deadly and most certainly destructive.
Storm Surge Potential
When I was looking for property in Citrus County one of my big concerns was the encroachment of wind-driven sea water with a storm – the so-called storm surge. Upon investigation I found what I expected – that if it was important to me personally to avoid surge potential I should avoid about one-third of the county’s land area – the western third.
NOTE: Illustration B, “map of Citrus County” might be useful to you here.
Most of that western third is undeveloped but there are two noteworthy communities within it, Homosassa and most of Crystal River. Therefore, early on I decided not to settle on the Gulf Coastal Lowlands but instead chose the Brooksville Ridge. In my opinion, the broad, hilly, sandy ridge is, by far, the safest place for a home or business in the county because of it’s higher elevations and greater ability to handle large amounts of precipitation often associated with a storm. The highest point in the county is within the Citrus Hills Golf Course above a 230′ contour – my Google Earth measurement has it at 235 feet.
ILLUSTRATION E – Storm surge portion of Citrus County, the western third (color-coded). T = tropical storm and the numbers represent hurricane categories. Left click to enlarge or go to the next illustration for more detail.
FOR STORM SURGE ZOOM CAPABILITIES, click on this link:
To be fair, Citrus county seems not to have been visited by category 5 or 4 hurricanes though at nearby Cedar Key a 1896 hurricane was a category 4 according to some estimates – crediting it with 135 mph winds.
NOTE: As far as we know, only three Category 5 storms have struck the U.S.A. – the 1935 Florida Keys or Labor Day hurricane, Hurricane Camille which hit Mississippi in 1969, and 1992’s Hurricane Andrew. The records aren’t good enough to say whether any earlier storms were Category 5 by today’s standards and they don’t go back very far with respect to the length of time that such storms have visited the North American mainland.
But lesser tropical cyclones, like tropical storms and tropical depressions, can produce both microbursts and tornadoes and simple straight-line gusts can far exceed the sustained wind velocity of such storms. Of course this is true for hurricanes too. Illustration G below shows initiation points of tornadoes spawned by tropical cyclones (e.g. tropical depressions, tropical storms, hurricanes) from 1995 through 2010. The entire report is available in the PDF format here:
– ILLUSTRATION G –
Please enlarge this with a left click. This illustration is on page 7 of Roger Edwards’ report which is available to you as the previous PDF document link titled Tornadoes Tropical Cyclones.
Recently, I looked into the proximity of past storms near my church and created a graphic for those who might be interested. Since the church is located in Lecanto and near the geographical center of Citrus County, I’m including the graphic in this weblog entry. Notice that I picked a small radius of 25 miles yet the illustration clearly shows a lot of activity. Had I picked a larger radius, say 50 miles, the graphic would show many more storms ( for an example of what I mean, see illustration D with a 100 mile radius centered on Inverness).
– ILLUSTRATION H –
Note: If you would like to utilize the program I used to derive illustration D and illustration H, here is a link:
The Relationship Between Wind Velocity and Its Potential Force
There is one last point I’d like to make and I have found in my years of teaching that there are many people who do not know this: One would think that the potential force of an 80 mph wind would be twice that of a 40 mph wind. But that is not true. The relationship is not linear – it is exponential. An 80 mph wind has FOUR TIMES the potential force of a 40 mph wind. When someone looking at the historical chart above sees mostly tropical storms (green) and category 1 hurricanes (yellow) they typically tend to minimize the dangers. They don’t realize that an 80 mph category 1 hurricane wind is far worse than a 60 mph tropical storm wind. I’ve done the math and, as it turns out, an 80 mph hurricane wind has 1.78 times the potential force of a 60 mph tropical storm wind (or close to twice the potential force). So, in even more simple terms, small increases in wind velocity result in large increases in potential force! For more discussion on the relationship between velocity and force, click on this link to a previous weblog entry:
My next mission is to discuss this with some people in the area to learn their attitudes and feelings on the subject. I’m sure I will learn a lot and gain more knowledge and insight. For example, I’ll bet there are some who just don’t feel it’s worth the effort – that they will just evacuate and let insurance take care of things, or maybe take some losses and leave for good if a serious storm messes things up. Others must find permanent window and door protection to be “cost prohibitive” and have plans to somehow temporarily protect those openings – maybe at the last minute. None of those approaches work for me; there are just too many variables. For example, try buying plywood when it becomes fairly clear that a hurricane is coming your way. Or – consider what it might be like if you do plan to evacuate but wait too long and are unable to do so. Being inside a home that is breaking apart during a serious hurricane is no picnic.
NOTE: See link below to “Window Protection Is Essential”.
I suspect that there are many who feel they have thought things through and that their apparent inaction is merely a function of our individual differences in thinking. Perhaps they do indeed have a “plan” albeit different than mine. What’s the saying – “Different strokes for different folks”? Regardless, I strongly recommend advanced preparation.
I observed complacency among many people in pre-Andrew Homestead and suspect it exists there again because, after all, that was 22 years ago. So why should I expect a greater awareness and more obvious preparation along the Nature Coast where Citrus County is located? The fact is, I don’t. But I can dream, can’t I?
Citrus County Emergency Management – http://www.sheriffcitrus.org/EM/
Disaster Preparedness (Florida Department of Health – Citrus County) http://www.floridahealth.gov/chdCitrus/disasterpreparedness.htm
Hurricane misconceptions: https://cloudman23.wordpress.com/2008/09/23/952/
Saffir-Simpson hurricane categories: http://www.nhc.noaa.gov/aboutsshws.php
Sustained winds: http://www.aoml.noaa.gov/hrd/tcfaq/D4.html
Window protection is essential: https://cloudman23.wordpress.com/2008/09/08/window-protection-for-hurricanes-is-essential/
The effects of hurricane winds upon a house: https://cloudman23.wordpress.com/2008/09/10/the-effect-of-hurricane-winds-upon-a-house/
Hurricane focus on Central Florida: https://cloudman23.wordpress.com/2008/09/13/hurricane-focus-on-central-florida/
Why is Florida so humid? https://cloudman23.wordpress.com/2009/07/04/why-is-florida-so-humid/