On August 29th, 2005, the winds whipped outside at a fierce 175 miles per hour, rain pounded on the rooftops, flooding imminent as levees strained and gave way pouring into New Orleans. The Category 5 hurricane terrorizing all cities and states on its war path of destruction; Katrina is what they call her and her storm surge reached 20 feet high. 1,836 was the final death toll that Hurricane Katrina caused and her affects were impacted over approximately 90,000 square miles. 80% of New Orleans was underwater and some places were up to 20 feet under. (11 Facts About Hurricane Katrina) This destruction is unimaginable to most of us but for those that experienced it, it is something they never want to experience again. Along Katrina’s route of destruction, tornados were developed wreaking havoc in other states. In this paper I will discuss, in depth, hurricanes and tornados and the destruction they cause to our nation.
The word hurricane was derived from the Spanish word “huracan” this word originated from a Mayan storm god. The word hurricane was used in the West Indies where they described any tropical cyclone. (Hurricane: What is a Hurricane?) The accurate definition of a hurricane is a “tropical cyclone with sustained winds that have reached speeds of 74 mph or higher” the storms are labeled as hurricanes when they gain their strength over days and weeks time. (Hurricane: What is a Hurricane?) Storms developing over the Atlantic Ocean or eastern Pacific Ocean are coined hurricanes. Regardless the name, all tropical cyclones develop the same way. These storms use warm, moist air as their fuel over the ocean and causes areas of lower air pressure below. The air from areas with higher air pressure pushes into the lower pressure area. This new air becomes warm and moist and it rises as well. As this warm air rises and rises, the air that surrounds begin to swirl in and take its place. As this warm, moist air rises and cools, clouds are now formed. This creates a whole system, spinning wind and clouds gaining power from the ocean’s warmth and water that evaporates from the surface. (How Do Hurricanes Form?) An interesting fact is that these storms that develop north of the equator rotate counterclockwise and south they spin clockwise. The Earth’s rotation is the cause for the direction of the storms. The storm continues to rotate and gain speed and the notoriously known eye is formed. The eye is calm and clear and has very low pressure the high pressure flows down into the eye. Figure 1 shows a diagram of a tropical cyclone in its development. (How Do Hurricanes Form?)
FIGURE 1 In order for a hurricane to form at least three conditions must be fulfilled. The three conditions are that a there is a pre-existing thunderstorm disturbance, warm ocean temperatures (80 degrees to a depth of 150 feet) and light upper level winds that do not change their direction and speed very much. (Hurricane Basics, 1999) Hurricane strength is measured by the Saffir-Simpson Hurricane Wind Scale, the scale is divided into 1 to 5 categories and details the conditions identified for the category to be assigned. The name Saffir-Simpson was developed by Herbert Saffir, a consulting engineer and Robert Simpson, Director of the National Hurricane Center. The five categories of a hurricane detail the specifics the storm presents and the damage it can cause. Figure 2 breaks the categories down and shows the miles per hour and destruction description that the storm can cause. (Hurricanes) The results shown in Figure 2 are no surprise especially given the aftermath of Hurricane Katrina; what amazes me is the shear strength a tropical cyclone/hurricane can develop over the ocean and the affect it has nationwide across many states in its path of destruction.
FIGURE 2
Category Sustained Winds Types of Damage Due to Hurricane Winds
1 74-95 mph
64-82 kt
119-153 km/h Very dangerous winds will produce some damage: Well-constructed frame homes could have damage to roof, shingles, vinyl siding and gutters. Large branches of trees will snap and shallowly rooted trees may be toppled. Extensive damage to power lines and poles likely will result in power outages that could last a few to several days.
2 96-110 mph
83-95 kt
154-177 km/h Extremely dangerous winds will cause extensive damage: Well-constructed frame homes could sustain major roof and siding damage. Many shallowly rooted trees will be snapped or uprooted and block numerous roads. Near-total power loss is expected with outages that could last from several days to weeks.
3
(major) 111-129 mph
96-112 kt
178-208 km/h Devastating damage will occur: Well-built framed homes may incur major damage or removal of roof decking and gable ends. Many trees will be snapped or uprooted, blocking numerous roads. Electricity and water will be unavailable for several days to weeks after the storm passes.
4
(major) 130-156 mph
113-136 kt
209-251 km/h Catastrophic damage will occur: Well-built framed homes can sustain severe damage with loss of most of the roof structure and/or some exterior walls. Most trees will be snapped or uprooted and power poles downed. Fallen trees and power poles will isolate residential areas. Power outages will last weeks to possibly months. Most of the area will be uninhabitable for weeks or months.
5
(major) 157 mph or higher
137 kt or higher
252 km/h or higher Catastrophic damage will occur: A high percentage of framed homes will be destroyed, with total roof failure and wall collapse. Fallen trees and power poles will isolate residential areas. Power outages will last for weeks to possibly months. Most of the area will be uninhabitable for weeks or months.
Reference: http://www.nhc.noaa.gov/aboutsshws.php The most damaging part of a hurricane is called the eyewall. In this location of the hurricane, winds are at their strongest and rainfall at its heaviest. The high winds are created due to rapid changes in pressure near the eye and it creates a great force. The right side of a hurricane is generally the most dangerous part due to the force it is travelling at.
Before a hurricane can become a hurricane it passes through distinct stages; two main stages are a tropical depression and a tropical storm. A tropical depression is where the storm develops a closed swirling this is where counterclockwise wind are blowing around the center of low pressure. Tropical depressions will have a maximum speed of 38 mph or less for the power of its winds. A tropical storm establishes its name when winds reach a maximum wind of between 39 and 73 mph. Once winds reach 74 mph or higher the storm can be classified as a hurricane. Once classified a hurricane the storm must be named. (Hurricane: What is a Hurricane?) Naming hurricanes are important because often throughout the season multiple hurricanes can develop so using names provides it easier for meteorologists, researchers, EMT’s, ship captains and citizens to talk about and understand the hurricane specified by name. The World Meteorological Organization developed a list of hurricane names in alphabetical order as they are developed and discovered throughout the season. Names cannot repeat within six years of using the names and severe storms names are completely removed from being used ever again. (Hurricane Names - How Are Hurricanes Named?) Figure 3 shows the schedule for hurricane names used and to be used in the future. Some names that have been retired that most of us may know are Sandy (2012), Irene (2011), Gustav and Ike (2008), Felix (2007), Katrina, Rita and Wilma (2005) and Andrew (1992). For about 300 years people have been giving names to hurricanes. In the Caribbean Islands they began naming the storms after the saint of the day from the Roman Catholic liturgical calendar for the day the hurricane occurred. In earlier days in the United States we used latitude and longitude to distinguish between storms. This was difficult to use for communication, thus names were created. (Hurricane Names - How Are Hurricanes Named?)
FIGURE 3
Names used for Atlantic Tropical Storms
2012 2013 2014 2015 2016 2017
Alberto Andrea Arthur Ana Alex Arlene
Beryl Barry Bertha Bill Bonnie Bret
Chris Chantal Cristobal Claudette Colin Cindy
Debby Dorian Dolly Danny Danielle Don
Ernesto Erin Edouard Erika Earl Emily
Florence Fernand Fay Fred Fiona Franklin
Gordon Gabrielle Gonzalo Grace Gaston Gert
Helene Humberto Hanna Henri Hermine Harvey
Isaac Ingrid Isaias Ida Ian Irma
Joyce Jerry Josephine Joaquin Julia Jose
Kirk Karen Kyle Kate Karl Katia
Leslie Lorenzo Laura Larry Lisa Lee
Michael Melissa Marco Mindy Matthew Maria
Nadine Nestor Nana Nicholas Nicole Nate
Oscar Olga Omar Odette Otto Ophelia
Patty Pablo Paulette Peter Paula Philippe
Rafael Rebekah Rene Rose Richard Rina
Sandy Sebastien Sally Sam Shary Sean
Tony Tanya Teddy Teresa Tobias Tammy
Valerie Van Vicky Victor Virginie Vince
William Wendy Wilfred Wanda Walter Whitney

There are two other storms relatively close in characteristics to a hurricane in fact they are all just different names for the same weather pattern. According to the webpage from Live Science, they are all “powerful, spinning storms collectively called tropical cyclones, which form over warm tropical waters and reach sustained internal wind speeds of 74 mph.” (How Do Cyclones, Hurricanes and Typhoons Differ?, 2012) The location of the storm generally designates its name. Hurricanes start in the Atlantic, Caribbean and northeast Pacific, typhoons form in the western Pacific and southeastern Indian Ocean. If these storms develop in certain parts of the Indian Ocean or the southwest Pacific Ocean it will go by cyclone. These three storms all rotate counterclockwise if they form in the Northern Hemisphere and clockwise if they are in the Southern Hemisphere. (How Do Cyclones, Hurricanes and Typhoons Differ?, 2012) El Nino is a condition where ocean surface temperatures because abnormally warmer in the Pacific. It has been proven that El Nino events have given rise to more tropical storms in the eastern Pacific and a decrease in tropical storms in the Atlantic, Gulf of Mexico and the Caribbean Sea. Hurricanes are largely damaging, intimidating forces of nature and people should not take this fact for granted. Precautions must be taken to weather the storm, literally. There are multiple things people in hurricane areas should do to be prepared; preseason preparation, what to do when a warning is issued, before the storm tips, during the storm and after the storm. Pre-season preparation is always a good thing to do just in case. Make sure you are aware of evacuation routes, make sure you have necessities for preparing your home for safety and damage, have plenty of supplies (batteries, flashlights, non-perishable foods and water). During a watch or when a warning is issued evacuate lower lying areas, prepare your home for damage, stock up on fuel, water and food, and if called to evacuate – do it! Before the storm you should still be prepared with plenty of food and water, secure a safe room, make sure you have completely secured your home to help weather the storm, keep a close eye on the weather reports and make sure your tools, supplies and first aid kit is readily available. During the storm it is necessary to stay in your safe room, do not go near windows, use the phone or use candles, continue to monitor weather and remain indoors. It is crucial to stick to a set plan before, during and after the storm. (Hurricane Safety Tips) Another devastating storm system is tornadoes. Tornados are violent and destructive storms – they are a rotating column of air that originates from the thunderstorm to the ground. Some tornados are capable of winds that may reach speeds of up to 300 mph! Their damage can be so violent that they can destroy buildings, homes, uproot trees and launch vehicles and any other debris in its pathway. A tornadoes path can be more than a mile wide and 50 miles long; on average there are a reported 1000 tornados a year. (Tornadoes) So how does a tornado form? A tornado is the result of a super cell storm. Cold air and warm air join in a set pattern as the cold air drops, warm air rises. The warm air then begins to twist making a spiral formation and that is the funnel cloud that we are able to visually see naming it a tornado. (How Do Tornadoes Form?) The strength of these super cells or tornadoes is measured by the Fujita-Pearson Tornado Scale. The highest numbered tornado is an F6; the winds at this point are 261-318 mph. At this point homes can be lifted from their foundations and carried great distances from the force this sizes tornado exudes. Figure 4 displays the Fujita-Person Scale and describes the scale number, intensity phrase, wind speed and types of damages caused. The Fujita-Pearson Scale was designed in 1971 by Professor Fujita and Allen Pearson who was Director of the National Severe Storm Forecast Center. Their scale is used to help measure the characteristics as well as the length and width of the tornadoes path. We have all heard the saying “size doesn’t matter,” but for the sake of this topic and tornadoes this saying is untrue; the size of a tornado is not a good measure of the intensity of the storm. (Measuring the Strength of a Tornado)
FIGURE 4
F Scale Number Intensity Phrase Wind Speed Type of Damage
F0 Gale tornado 40-72 mph Minor damage to chimneys, trees and or tree branches, and street signs
F1 Moderate tornado 73-112 mph This is the beginning of hurricane wind speed: loss of roofs, mobile homes dislodged from secure bases, vehicles moved from roadways, attached garages may be destroyed
F2 Significant tornado 113-157 mph Considerable property damage: roofs torn off frame houses, mobile homes demolished, mature trees snapped or uprooted
F3 Severe tornado 158-206 mph Roof and walls torn off well constructed houses, large non-permanent structures overturned, most trees uprooted
F4 Devastating tornado 207-260 mph Well-constructed houses leveled, vehicles of all sizes air lifted, and large objects become airborne with destructive force
F5 Incredible tornado 261-318 mph Strong frame houses lifted off foundations and carried considerable distances, then dropped, automobile sized objects fly through air in excess of 100 meters, trees debarked, steel reinforced concrete structures badly damaged
F6 Inconceivable tornado 319-379 mph These winds are very unlikely. If this level is ever achieved, evidence for it might only be found in some manner of ground swirl pattern, for it may never be identifiable through engineering studies
(Measuring the Strength of a Tornado)
Figure 5 shows more interesting statistics for tornadoes and classifies them into weak, strong and violent. (Measuring the Strength of a Tornado)
FIGURE 5 Weak Strong Violent
Of all tornadoes 69% 29% 2%
Tornado deaths 5% 25% 70%
Time 1-10+ mins. 20+ minutes may exceed 1 hour
Wind speeds 110 mph 110-205 mph greater than 205 mph
(Measuring the Strength of a Tornado)
Microbursts are another weather phenomenon; they pose a great threat to aviation. Microbursts are a “downdraft in a storm that is less than 2.5 miles in scale.” Some can pose a threat to people and buildings but primarily the threat is in aviation. Some microbursts are capable of doing more damage than tornadoes, where speeds can quickly reach 150 mph. There are some factors that cause microbursts; mid-level dry air, cooling beneath thunderstorms cloud base, sublimation and rain or hail within the storm. Some microburst may be caused by multiple factors and some maybe only one. (What is a Microburst?)
Another aspect to tornadoes is waterspouts. There are two categories that waterspouts fall into; tornadic and fair weather. Tornadic waterspouts form over water or they also can move from land into water. The characteristics of a tornadic waterspout are the same as a land tornado. Tornadic waterspouts form due to high winds, large hail and dangerous lightening. Fair weather waterspouts form along those dark flat bases of cumulus clouds. They may not be associated with a storm. Fair weather waterspouts are opposite to tornadic spouts in that they develop on the surface of the water and work upward; these spouts form in lower wind conditions and don’t usually move much. (A Waterspout is a Whirling Column of Air and Water Mist)
The map in Figure 6 shows Tornado Alley a prominent area affected by tornado activity. The states included in this area are Texas, Oklahoma, Nebraska, eastern Colorado and western Iowa. This area is placed into this category due to a high amount of violent tornadoes as well as a consistent season for the tornadoes year after year. Even thought this area is more prone to tornadoes the saying goes, “Tornadoes can and do happen at any time of the year in just about any location.” In September 2001, tornadoes hit Washington D.C. so if the conditions are right tornadoes can develop anywhere. (When and Where Do Tornadoes Occur?)
FIGURE 6

I used data from National Atlas’ website to compare Lubbock, Texas (Figure 7B) and Hattiesburg, Mississippi (Figure 7A) to depict tornado occurrences. Lubbock, Texas is in Tornado Alley and here we can see that there is a distinct “season” for tornadoes. In comparison, Hattiesburg, Mississippi is not in Tornado Alley and we can see that the occurrence of tornadoes is much lower and there is not a pattern for the occurrence of tornadoes. (When and Where Do Tornadoes Occur?)

FIGURE 7A FIGURE 7B The rotation of tornadoes are much like hurricanes; in the Northern Hemisphere they rotate counterclockwise and the opposite for the Southern Hemisphere. Tornadoes are spawned from parent thunderstorms and so they spin the same way as the storm does. (Answer Archive: Tornado Science) There are things to look for to spot a tornado; although it is possible for them to occur rapidly and without warning. The following are things to watch and listen for:
• Loud roar or rumble
• Hail or heavy rain – followed by dead or calm/fast intense wind shifting
• Whirling dust/debris under a cloud base
• Strong rotation in the cloud base
• Small blue-green to white flashes – power lines snapping
(Tornado Safety)
Safety measures should be in place before, during and after a tornado just like described for a hurricane. Go to the basement; cover yourself with a mattress or sleeping bag. Keep away from heavy objects. Head protection is a viable option such as a bike helmet. If you do not have a basement avoid windows, get to the lowest floor, in a small center room like a bathroom or a closet, under a stairwell or an interior hallway; crouch as low as possible to the floor and cover your head with your hands. Cover yourself with something like a mattress or comforter. Since a tornado can happen any time it is important to keep a normal supply of batteries, flashlights, non-perishable foods, water, a first aid kit and other supplies that you may deem necessary for a natural disaster. (Tornado Safety)
All in all hurricanes and tornadoes are natural disasters that we must be prepared for. No matter what part of the country we live in any of these are a possibility. The destruction they cause can be catastrophic as I described Hurricane Katrina in my introduction, the cleanup is ongoing and the destruction still visible. It is important that our nation is prepared and knowledgeable about these storms so that when they occur we can take proper action to survive and weather the storms.

Works Cited
11 Facts About Hurricane Katrina. (n.d.). Retrieved October 20, 2013, from DoSomething.org: http://www.dosomething.org/actnow/tipsandtools/11-facts-about-hurricane-katrina
A Waterspout is a Whirling Column of Air and Water Mist. (n.d.). Retrieved from NOAA: http://oceanservice.noaa.gov/facts/waterspout.html
Answer Archive: Tornado Science. (n.d.). Retrieved from USA Today: http://usatoday30.usatoday.com/weather/resources/askjack/archives-tornado-science.htm
How Do Cyclones, Hurricanes and Typhoons Differ? (2012, October 11). Retrieved from LiveScience: http://www.livescience.com/32180-how-do-cyclones-hurricanes-and-typhoons-differ.html
How Do Hurricanes Form? (n.d.). Retrieved October 20, 2013, from NASA Space Place: http://spaceplace.nasa.gov/hurricanes/
How Do Tornadoes Form? (n.d.). Retrieved from Universe Today: http://www.universetoday.com/75695/how-do-tornadoes-form/#ixzz2iJEoOUVv
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Hurricane Names - How Are Hurricanes Named? (n.d.). Retrieved from geology.com: http://geology.com/hurricanes/hurricane-names.shtml
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Hurricane: What is a Hurricane? (n.d.). Retrieved October 20, 2013, from The Weather Channel: http://www.weather.com/outlook/weather-news/hurricanes/articles/hurricane-what-is-a-hurricane_2010-05-24
Hurricanes. (n.d.). Retrieved from Oracle: Think Quest: http://library.thinkquest.org/J001246/hurricanes.htm
Measuring the Strength of a Tornado. (n.d.). Retrieved from EMSA Online: http://www.emsaonline.com/mediacenter/articles/00000183.html
Tornado Safety. (n.d.). Retrieved from spc.noaa.gov: http://www.spc.noaa.gov/faq/tornado/safety.html
Tornadoes. (n.d.). Retrieved from Weather Wiz Kids: http://www.weatherwizkids.com/weather-tornado.htm
What is a Microburst? (n.d.). Retrieved from srh.noaa.gov: http://www.srh.noaa.gov/ama/?n=microbursts
When and Where Do Tornadoes Occur? (n.d.). Retrieved from NationalAtlas.gov: http://nationalatlas.gov/articles/climate/a_tornadoes.html