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Tampa, FL wx impacts

Page history last edited by jtroksa2@... 12 years, 3 months ago
Tampa, Florida









Jeffrey Troksa, jtroksa2



Tampa is a United States city in the state of Florida. The area was first discovered to the old world by Spanish explorer Ponce De Leon in 1513; but it was not until 1824 when an American military base was built was the area populated by modern civilization. In 1845 Tampa became an official U.S. territory. Due to its port and new technology the town has steadily grown population wise and economically since the1880’s continuing into present day. Today it is demographically unique as well as geographically impressive. It is a coastal city that surrounds a great portion of a bay harbor within the Gulf of Mexico. This bay is most commonly called the “Tampa Bay Area” which is the seventh largest port in the nation. Tampa city is the third most populated Florida city and is founded on its port, which fuel its economy. Tampa also thrives by its tourism which attracts people with its weather and its waters. It is one of the most diverse American cities culturally as minorities make up 1/3 of the population. It has unique wildlife and marine ecology based on Tampa’s tropical weather. [2][3]










Geographic Location



Tampa is located on the western coast of central Florida along the Gulf of Mexico. It is part of Hillsborough County, which is highlighted in red on the Florida state map below [4]. The city of Tampa is also highlighted in bright red on the smaller map, on the left of the image below. Tampa is located at a longitude of -82.48W and latitude of 27.96 [5]. The city is surrounded by large bodies of water on three sides. To the West is Old Tampa Bay, and to the East is Hillsborough Bay. These two expanses of water flow together south of the city to from Tampa Bay, which flows into the Gulf of Mexico to the West. The Palm River runs into the East side of the city, while the Hillsborough River cuts through Tampa and flows into the Hillsborough Bay.











Topography of Tampa




The entire state of Florida is a large plateau with land elevations ranging from sea level to 345 ft (105.2 meters) above sea level. The average elevation of this state is just 100 ft (30.5 meters) above sea level [7]. According to data collected by the United States Census Bureau, the city of Tampa is 170.6 mi2, with 112.1 mi2 consisting of land and 58.5 mi2 made up of water. The highest elevation of Tampa is 48ft (14.6 meters) above sea level, while in some areas of the city, the elevation drops to sea level [8].










 Landsat Image of Tampa and surrounding areas by NASA: Robert Simmons












The climate in Tampa, FL is considered tropical to subtropical. The summers are generally warm and wet, while the winters are cooler and drier [11]. Even so, during the winter months temperatures remain around 60 degrees F. Below the high, low and average temperature for Tampa are seen:   






Over the course of an entire year, the average high is approximately 81.7 degrees, the average low is 63.5 degrees and the mean temperature is 72.6 degrees [13]. Looking at the graph above we see that the months of June, July and August are the warmest with averages in the 80’s and highs nearing 90 degrees. On the other hand January, February and December are the coldest months with averages in the 60’s.







 As noted for a tropical and subtropical climate, the months of June, July, August and September are by far the wettest, with August having the most precipitation of 7.60 inches. In other months the precipitation drops off significantly; the driest month in Tampa is November with 1.62 inches of precipitation. [15] To give one an idea for the amount of sun an area receives, it is interesting to look at Sunshine hours. This is simply a measure of the percentage of daytime hours that had sun shining on the ground. Clearly, Tampa more often than not has clear sunny skies. Not surprisingly, Tampa is a popular tourist destination because of its sunny days and warm temperatures.





Tampa has an average of 597 Heating Degree Days per year and 6565 Cooling Degree Days per year, on a base 65 degree temperature. There are 4912 Growing Degree Days based on a base 60 degree temperature. [16]


















Total population of Tampa in 2000 was 303,447 [18], while the 2006 census counted 332,888 citizens. [19]


Below are demographics of the 332,888 citizens of Tampa in the year 2006:






Tampa, Florida




































































Other Race












Hispanic or Latino of any race












Speak multiple languages












Acquired High School Diploma












Acquired a Bachelor’s Degree or higher
























Median Value of Households










Persons per Household


























Recovering from effects of pollution, Tampa Bay is Florida’s largest estuary and a habitat for many different species of animals. Like most estuaries, Tampa Bay has freshwater rivers feeding into it along with saltwater from the ocean. Because of this and security from the giant monsters that prey upon them, Tampa Bay has become a home to all types of fish at least during some part of their growth process. Even the endangered Florida manatee has been able to make Tampa Bay its

home. These thousand pound creatures have been increasing their numbers in Florida through safe habitats like Tampa Bay. Some other inhabitants of the water here include the ghost crab, dolphins, the snook, the sea turtle, and the bay scallop. Land around the water is full of mangroves and marshes with giant trees, allowing nesting places to birds of all types. The El Nino rains in 1998 helped many bird species to almost triple before their numbers went back down in 1999, such as the White Ibis. It is also home to the rare blue heron, pelicans, and the America oystercatcher. Like the rest of Florida, vast mangroves full of diverse vegetation are a native inhabitant of Tampa. Cordgrasses and sea grapes are two of the dominant plants that fill the salt marshes and mangroves. Giving a home to about 200 species of fish and 25 different species of birds, the diverse plant life of Tampa gives the city a unique environment attracting tourists from all over the world to come view the distinctive wildlife. [20][21]













Even though Tampa Florida is still known for its cigars it has become the industrial, commercial, and financial hub of Florida's west coast. In fact a third of the state's entire population lives within a two-hour drive of the city. It has a very diverse economy base which came after WWII, where there was a movement that appealed to a wide variety of businesses, especially those that were more office-oriented and service-related. Currently, Tampa is not only a center for cigars and tourism, but also for agriculture, food processing, electronics, health care, and finance. Many agriculture-related industries have been attracted to this area, and it has become a foreign trade zone where goods can be uploaded without going through import duties. [22]



Tampa is located in the county of Hillsborough, which alone has an estimated 740,000 employees. Tampa's port is the seventh largest in the nation and it is Florida’s largest tonnage port, which handles almost half of all seaborne commerce that goes through the state. Also, Tampa is currently second in the state in terms of cruise ship travel, only behind Miami. [23] ]









Land Use
Resting on the mid-west coast of Hillsborough county, Florida, with its naturally convenient bowl shaped opening, Tampa remains a popular spot for docking boats.  However, Tampa’s land usage flows much deeper than the surface.  Not only is the Tampa Bay useful for travel, it is also home to many amphibians and wildlife.  This 200sq ft block of land contributes greatly to providing resources for our nation and others. [24]









Agricultural Information




Tampa is a decently urbanized area and therefore agriculture does not play a significant role in its economy. Fishermen, farmers, and forestry positions together only make up 2% of jobs in the area. In the last census, this combination of jobs had less than 285 people fulfilling it. However, sharing boundaries with the Gulf of Mexico, Tampa provides a unique environment for docking ships. Tampa benefits greatly off of its unique shoreline. Cruise ship companies crave the location for docking. It’s the perfect distance away from popular Caribbean vacation spots, so guests can spend just the right amount of time on the ship and on the beach. [24]












Tampa has become very urbanized since its discovery in the 1500’s. According to the last census (2000) Tampa has a population of 303,447 persons. The 2006 census speculates that this number has grown to around 330,000. With such a continuance of increasing population, Tampa’s landscape and usage is becoming more and more urbanized.










1684 miles of road are spread throughout the city of Tampa, Florida [27] including the three major interstate highways: Interstate 4, Interstate 75, and Interstate 275. Tampa is also home Tampa International Airport which is also known as “America’s Favorite Airport.” [28] Also located in this city is the Tampa Union Station which was built in 1912. In 1981 it was closed but later reopened in 1998. It got its name because when it originally opened it connected three railroads which created a “union” of the tracks. However now it only has two railroads that arrive and depart from the station. [30] Whether you’re a citizen of Tampa or just there visiting you can get around the city using the trolley system, electric streetcar line, the bus system managed by HARTline, or just by catching a cab. [29]























 [1] http://goflorida.about.com/od/tampa/ss/tampa_downtown.htm


[2] http://www.census.gov/popest/cities/tables/SUB-EST2006-01.xls


[3] http://www.tampagov.net/


[4] http://www.naco.org/Template.cfm?Section=Find_a_County&Template=/cffiles/counties/usamap.cfm


[5] http://forecast.weather.gov/MapClick.php?CityName=Tampa&state=FL&site=TBW&textField1=27.959&textField2=-82.4821&e=1


[6] http://en.wikipedia.org/wiki/Image:Hillsborough_County_Florida_Incorporated_and_Unincorporated_areas_Tampa_Highlighted.svg


[7] US Geological Survey (http://erg.usgs.gov/isb/pubs/booklets/elvadist/elvadist.html#Highest">http://erg.usgs.gov/isb/pubs/booklets/elvadist/elvadist.html#Highest)


[8] US Census Bureau (http://quickfacts.census.gov/qfd/states/12/1271000.html">http://quickfacts.census.gov/qfd/states/12/1271000.html)


[9] http://pubs.usgs.gov/of/2007/1051/">http://pubs.usgs.gov/of/2007/1051/




[11] http://www.wordtravels.com/Cities/Florida/Tampa/Climate












[17] http://www.floridahispano.com/assets/images/tampa2ED.jpg




[18] http://www.census.gov/popest/cities/tables/SUB-EST2006-01.xls


[19] http://factfinder.census.gov/servlet/ACSSAFFFacts?_event=Search&geo_id=16000US1714000&_geoContext=01000US%7C04000US17%7C16000US1714000&_street=&_county=tampa&_cityTown=tampa&_state=04000US12&_zip=&_lang=en&_sse=on&ActiveGeoDiv=geoSelect&_useEV=&pctxt=fph&pgsl=160&_submenuId=factsheet_1&ds_name=ACS_2006_SAFF&_ci_nbr=null&qr_name=null®=null%3Anull&_keyword=&_industry


[20] http://www.gulfbase.org/bay/view.php?bid=tampa


[21] http://www.tampaelectric.com/manatee/plantlife/


[22] http://www.answers.com/topic/tampa-economy


[23] http://www.tampachamber.com/economic_development.asp


[24] http://factfinder.census.gov/servlet/QTTable?_bm=y&-qr_name=DEC_2000_SF3_U_DP3&-ds_name=DEC_2000_SF3_U&-_lang=en&-_sse=on&-geo_id=16000US1271000


[25] http://www.cnn.com/TRAVEL/DESTINATIONS/9703/tampa.florida/images/florida.bball.map.jpg


[26] http://www.tampa.world-guides.com/tampa_photos1.html


[27] http://www.tampagov.net/files/city_services_guide.pdf


[28] http://en.wikipedia.org/wiki/Tampa-St._Petersburg-Clearwater,_Florida_Metropolitan_Statistical_Area#Transportation









 Weather Impacts




(Stephanie Hayden: shayden3)
Tampa typically receives two types of thunderstorms. The first being air mass thunderstorms, because those tend to occur at mid-latitudes. Air mass thunderstorms are what one would consider an average storm; they are not severe. These thunderstorms help keep Tampa lush and green. That is not the only type of storm this city is capable of producing.  Tampa lies in the southeast portion of the Great Plains  mesoscale convective system, which is where supercells and tornadoes are produced. These storms are considered severe, because they bring hail, 58mph winds, and or tornadoes. It is arguable that these storms are more destructive than helpful. 
Frequency of events- The entire state of Florida has a very active weather system. While thunderstorms are more frequent in the spring and summer months, Tampa also receives a handful of storms in the winter. Many times, when it is snowing up north, it is storming here in Florida.
How does this happen? Tampa’s air-mass thunderstorms (also known as isolated thunderstorms) are developed by heating or lifting along weak boundary lines usually when it’s humid outside. Severe storms in this area have four ingredients. There must be moisture present in the air. The atmosphere must be unstable. There has to be a storm trigger, such as heating or lifting. The last product is wind shear. With these items mingled, storms have the freedom to brew in Tampa! Tornadoes require the same ingredients; however the wind shear must be vertical.


 Impact: Currently, thunderstorms help to revive Tampa’s Bay and Lake Okeechobee, since the 2007 drought that brought those waters 6 feet below its average 15 feet depth. Without thunderstorms, Tampa would still be suffering from drought. 







El Nino

 Michael Kehl, mkehl2






El Niño is a slight increase (a few degrees) in water temperature over the large body of water called the Pacific Ocean. The event of El Niño occurs randomly in intervals of two to seven years. The name “El” means little boy or Christ child because the conditions tend to happen around the Christmas season. So why does the ocean become warmer? Generally winds blow westward from areas of high pressure on the eastern Pacific to areas of lower pressure on the western Pacific. The winds cause water to flow westward while heating up and rising as they approach the western Pacific. There is also a countercurrent flowing eastward that is much cooler in temperature. During an El Niño the pressure pattern is disrupted and is higher in the western Pacific and lower in the eastern Pacific. The winds and direction of water-flow are also changed. The warm water now flows eastward as the countercurrent flows westward. The warm episode of water can occur for a few weeks or for months at a time. When it occurs for months at a time the effects can be much more disastrous. The upwelling currents of cold nutrient-rich water that generally exist on the eastern Pacific are overtaken by the warmer water thus cutting off much of the nutrients fish need. More marine plants and animals die, their decomposing bodies deplete the oxygen supply in the water and large amounts of hydrogen sulfide results. The hydrogen sulfide also contributes to the death toll of marine species and consequently reduces the fish harvest for many fishing companies.
           So how is the Atlantic Ocean affected? The large area of unusually warm water influences the latent heat of condensation and moisture content of the westerly winds aloft. Causing some regions of the world to experience more rainfall than normal while other regions see less rainfall than normal. In the Atlantic Ocean the winds aloft tend to disrupt the organization of thunderstorms that are vital for hurricane development. Therefore there are less hurricanes during a stronger El Niño event. This directly affects Tampa, Florida as they often experience the destructive effects of hurricanes. 






Amber McNelis, mcnelis2





One of the most common forms of destructive weather occurrences, lightning, strikes about 3 million times a day worldwide. [5]  Most commonly occurring during thunderstorms, lightning is a release of electrical energy in the atmosphere.  The formation of lightning is still greatly fought about by scientists, even though it occurs so often.  All that is known is the electrical power constructs within the thunderstorm cloud and is released through a bolt of lightning. [6]  Thunderstorm clouds are able to produce thousands of lightning strikes. [7]  The types of strikes are categorized by the location of the starting and end points of the strike, including cloud to ground, cloud to cloud, and ground to cloud.  All of these are caused by the electrical charge between the two objects.  There are many classifications of lightning.  Two well-known types are heat lightning and sheet lightning.  Although given different names from different locations, both of these types are simply regular lightning further from the storm.  For instance, heat lightning may seem to be lightning on a calm night, but there is actually a thunderstorm in the distance producing the lightning.  From the place where the “heat lightning” is seen, the thunder cannot be heard. [8]






            Tampa is sometimes referred to as the lightning capital of the nation.  Although chances of being killed by lightning are very slim, the number of deaths from lightning is about ten deaths per year in Florida. [9]  Thunderstorms, where most lightning is produced, occur most often in the summer months in Florida.  Most summer afternoons, thunderstorms will erupt and last for a while, sometimes becoming quite severe, but bringing behind it a nice, calm evening.  Due to the frequency of lightning during summer afternoons, many construction and landscaping companies, water parks, and other places end up packing up and closing during these storms in order to ensure safety for the people.  [8]









 Jenna Vickers, jvicke2


downburst is created by an area of rain-cooled air that, after hitting the ground level spreads out in all directions creating strong winds.  These winds can get up to 150 miles per hour.  It can be said that they sound like a giant whistle, and get extremely loud.  Downbursts create vertical wind shear which is one of the primary ingredients for a thunderstorm.  [10]   


Table 1. Dry vs. Wet Microburst Characteristics








Dry Microburst




Wet Mircoburst




Location of Highest Probability


Cloud Bases

Features below Cloud Base

Primary Catalyst

Environment below Cloud Base

Surface Outflow Pattern





Little or none

As high as 500 mb


Evaporative cooling

Deep dry layer/low relative humidity/dry adiabatic lapse rate






Moderate or heavy

Usually below 850 mb

Shafts of strong precipitation reaching the ground

Downward transport of higher momentum

Shallow dry layer/high relative humidity/moist adiabatic lapse rate

Gusts of the direction of the mid-level wind






There are lasting effects from downbursts; in fact damage from downbursts can be so severe that it can be mistaken for tornado damage.  However, when closely looking at the damage pattern from a downburst it is divergent, which means the winds were flowing outward, rather than in a circular pattern like a tornado. Downburst damage can cover hundreds of square miles, or just a single field, “microbursts” are the names given to the small ones.  [12] 


Although not much can be found on the frequency of downbursts in Tampa, Florida, they most definitely do occur there.  Summertime in Florida is the main time when downbursts occur, because there are many thunderstorms every afternoon which can sometimes become severe.  These severe thunderstorms can include downbursts.  However, the storms usually disappear by mid evening.  According to the chart above Tampa would most likely experience wet microbursts.  [13]














Tropical Cyclones
Lisa Neal (lmneal2)









Tropical cyclones are violent and deadly storms that affect much of the coastal areas in the United States. Under the right circumstances they are known as hurricanes when they are located in the Atlantic Ocean. It is not, however, just the hurricane itself that causes a loss life and mass destruction, but it is the four destructive forces that do.  The first of the four destructive forces is a storm surge. This is an abnormal rise in sea level associated with the movement of a hurricane over a coastal region. This is what causes the most structural damage and flooding. The second destructive force is inland flooding. This typically occurs with slow moving hurricanes that produce several inches of rain. Thirty to forty inches have been previously recorded! Contrary to popular belief it is actually inland flooding that causes the most fatalities, not storm surge. Next we have high winds. Hurricanes can produce winds between 74 mph to over 155 mph depending on the category. Although these winds can produce significant amounts of damage, they are not nearly as bad as the damage created by storm surges and inland flooding. Hurricanes also have the ability to produce tornadoes which brings us to our final destruct force; however, these are generally weaker tornadoes [15].



                   With the severity of hurricanes, and the location of Tampa, hurricanes are often likely to strike. It is estimated that hurricanes occur every 3.51 years [16]. However a hurricane has not actually directly hit Tampa since 1921. In order for hurricanes to occur, four key ingredients must be present [15]. These four things include:




  • A sea-surface temperature greater than or at 81°F




  • The surface layer of warm water in the ocean must be deep, typically around 60 meters or more



  • Weak wind shear




  • The location must be at least 5 degrees north or south of the equator.




    • Tampa is 27 degrees north of the equator making susceptible to hurricanes [17] 





If a hurricane were to directly strike Tampa as it did in 1921 much more damage would be produced [18]. Nearly 332,888 citizens currently populate Tampa and could be affected by a hurricane [19].  According to SPTimes “The same Category 3 storm [Hurricane of 1921] today would cause more than $13-billion in damage in Pinellas County alone and would force the evacuation of 430,000 Pinellas residents and damage almost a half-million dwelling units[18].” Tampa also now has 200 + square miles of metro area that could be damaged adding to the destruction cost. It is also one of the nations most car dependent metro areas and evacuation would take even longer than Katrina did, which was over 24 hours [20].  After the 1921 hurricane “it was thought that this hurricane would put a damper on the Florida land boom so residents rebuilt as quickly as possible and the land boom continued  [21].  "However the sales on houses near the coast have decreased due to  the fear of hurricane destruction [20].  Due to the fact the water surrounding Tampa is  rather shallow it is highly  vulnerable to produce a great deal of storm surge [22].




Inside a hurricane

















Case Study - Hurricane of 1921






On October 20, 1921 a “tropical disturbance” was spotted in the southwestern Caribbean near Jamaica, however the origin is unknown [23]. Back then, barometers were used to measure pressure in an area to help with forecasting hurricanes. When low pressure was recorded, boarding stations upon vessels radioed in an advisory at 10am the following morning. While they were not positive on the direction of the storm, they said it was probably moving northward. Three days later, the rain began to fall in Tampa around 4 am and lasted until October 25 at 9:15pm with little breaks in between [24]. On October 24, a warning was issued to the citizens giving them less than 24 hour notice [24]. When hurricane struck the next day it was full blown and hit with 100 mph winds [23]. It was this day when the lowest pressure had been ever recorded in the area getting as low as 28.81 inches. This hurricane is the most recent direct hit Tampa has received. At the time only 135,000 people lived within five counties of the hurricane including Pinellas County, where Tampa is located. The hurricane claimed eight lives and did between one and ten million dollars in damage [23] due to the 10-12 foot storm surge, high winds, as well as the 8.53 inches of rainfall [25].



                                                                                                       Hurricane Track





Since the hurricane of 1921, Tampa has been hit by other hurricanes; however, these did not directly hit the area. Since the direct hit, more preparations have been made, but if Tampa experienced the same category 3 hurricane today, an estimated 332,888 people in Tampa alone would be affected, not to mention the other towns in the county. Back in 1921 the amount of damage was considered to be light, but now it could cause more than 13 billion dollars in destruction [23]. Through the decades new technology advances have been made and hurricanes are now forecasted using a series of things including: satellites, buoys, reconnaissance aircraft, and radar [27]. Although new advances have been made and warnings can be issued much more sooner, it is also stated that Tampa has not fully prepared it self for a worst case scenario hurricane such as Katrina [28]. To see an interactive video clip of what Tampa would look like if Katrina hit it click the link below.




















Heat Waves


by Troy Sieburg (sieburg2)







Heat waves are one of the leading causes of weather-related death in the United States each year.[30]  Heat waves occur when strong high pressure systems sit over a certain area for a long time-span.[31]  Warm temperatures are not the only factor that contributes to a heat wave.  The relative humidity also influences the occurrence of a heat wave.[32]  Heat waves are usually associated with high humidity values.[33]  As the humidity rises, the heat index or apparent temperature also rises.  This can be seen in the heat index figure below.  A high heat index for a sustained period of time is what defines a heat wave.[34]




Heat Index Chart[35]




Heat waves are defined on a geographical basis, because the temperatures that constitute a heat wave vary from place to place.  Generally, a heat wave is considered a sustained period where the temperatures are above average.[36]




In Tampa, heat waves are most likely to occur between the months of May through October because these are the months where the city averages the highest temperatures of the year.  During these months, the high temperatures usually range from the upper 80 degree Fahrenheit to the lower 90 degree Fahrenheit values.[37]  These hottest months of the year also coincide with the rainy season in Tampa, so this humidity adds to the risk of heat waves occurring.[38]  The high humidity values raise the heat index values and make it more likely for heat waves to occur.  Tampa usually experiences multiple heat waves per year because of the high humidity the city experiences during its hottest months.[39]  The major source of this humidity comes from the Gulf of Mexico that is located directly to the west of the city.




Since Tampa experiences heat waves so frequently, the city has taken steps to help its residents cope with the heat when it occurs.  It opens facilities around the city for people who do not have air conditioned places to stay in when a heat wave occurs.[40]  The city also provides transportation to these shelters if people need it.  Their main concern is for the elderly and homeless people, because these are the people who are at the greatest risk when a heat wave occurs.













 by Mark Knaub (mknaub2)






    Compared to other weather-related phenomena, flooding accounts for the highest amount of property damage in the United States, and the second most deaths worldwide.  Flood duration and intensity depends on many factors, only some of which are related to the weather.  Directly related to weather systems are the intensity, duration, and the number of rain events that occur in a region.  The saturation level of soils is an important factor indirectly related to the weather that may enhance flooding.  Non-weather-related factors include land use, levees and dams and their effect on drainages, and the topography along a drainage[42].  There are three types of floods, which are distinguished from each other based on their predictability and location.  Flash Floodsoccur rapidly with little or no warning.  Typically, these are localized, short-lived, flooding events that affect small rivers and streams.  Flash floods are triggered by slow-moving thunderstorms that dump substantial amounts of rainfall within a short period of time over a localized area.  In the U.S., this type of flooding is most common during the summer months when thunderstorms form regularly.  Widespread floods occur when a significant amount of rain falls over a watershed for many days, leaving large portions of the rivers responsible for draining the watershed inundated for long periods of time.  Water levels along rivers rise very slowly, and ultimately surpass the confines of the rivers.  Widespread floods develop more slowly than flash floods and may last for weeks.  This flooding event affects large rivers, and thus, impacts a much greater area (multiple states) than flash floods.  As a result of the size and duration of widespread floods results property damage and economic losses are tremendous compared to flash flooding events[43].  Coastal floods occur when the ocean surface rises due to the development of storm surge associated with hurricanes and strong extratropical cyclones.  The inland extent of coastal flooding depends both on the intensity of the storm and the geographic and topographic features of the region.  Coastal flooding is generally more severe along the East and Gulf Coasts of North America than along the West Coast because of the greater number of storms and the flat coastal topography[44] ].


    The weather system affecting Tampa creates conditions suitable for the production of all three flood types.  Flash, widespread, and coastal flooding may occur separately contributing to different flood events, or a combination of these floods types may play a role in a single, significant weather event.


    Tampa experiences a wet season from May to September during which time the city receives a substantial amount of rainfall[45] ].  During these summer months, afternoon thunderstorms are a daily occurrence.  This constant rainfall may result in widespread flooding across the city along the Hillsborough River.  This widespread flooding is compounded by a few different factors.  Tampa is a greatly developed city.  Skyscrapers, condominiums, homes, and roads are everywhere, and more are being built everyday.  This development has crowded natural creeks that once collected storm water and the miles of pavement cover soil that once absorbed excess water[46].  Although Tampa has undergone a significant deal of urbanization, the drainage system for the city has not.  It is outdated and rapidly overwhelmed by the large amounts of water generated by extratropical and tropical cyclones.  The drainage system was developed early in Tampa’s history when rural-living predominated.  Pavement and large homes were not taken into consideration during the construction of the drainage system[47].  As a result of this overdevelopment and poor drainage system, rainfall from summer storms leads to the overflow of rivers and streams.  This excess water penetrates through the city along the major rivers, and creates widespread floods that inundate Tampa for several days or longer.  These same factors may result in flash flooding during the summer thunderstorms, but this type of flooding event is more commonly associated with tropical cyclones making landfall.



    Between June and November, tropical cyclones (hurricanes and tropical storms) affect the Gulf Coast of the United States.  These storm systems create vast amounts of damage due to their storm surge and associated coastal flooding[48].  Tampa is especially vulnerable to coastal flooding because of its low elevation, relatively flat topography, and location relative to OldTampa Bay, Hillsborough Bay, and Tampa Bay.  The highest elevation of Tampa is 48 feet above sea level, while some areas are exactly at sea level.  This low elevation, along with the flat topography, enhances the storm surge associated with tropical cyclones.  There is nothing to obstruct the storm surge as it moves inland, and thus, the coastal flooding may extend through the entire city of Tampa causing significant property damage.  Tampa is surrounded by three large bodies of water, making the city a peninsula.  Tampa Bay is open to the Gulf of Mexico.  As a result, a storm surge associated with a tropical cyclone that makes landfall on the Gulf Coast of Florida will directly hit the city of Tampa.  Such a storm surge will be enhanced by the presence of the inland bay, and the resulting destruction and devastation will be tremendous[49].  In 2004, Hurricane Frances caused significant flooding in downtown Tampa through the overflow of the Hillsborough River.  This flooding was caused by a record-breaking storm surge measured at the connection of the Hillsborough River with Tampa Bay.  The storm surge was recorded at 15.83 feet, which was nearly 4 feet above the normal high tide[50].


    The same tropical cyclones that generate coastal flooding are capable of producing flash floods.  When a tropical cyclone makes landfall, it may slow down significantly, while continuing to produce exceptional amounts of rainfall[51].  If such a tropical cyclone makes landfall near Tampa, and slowly moves over the city, a flash flood may be induced.  The vast amounts of pavement would increase runoff from the storm, rapidly overwhelming the poor drainage systems, and generating a flash flood.

























Lauren Mazurski - lmazur4






Blizzards are a type of dangerous winter storm that consist of high wind speeds and blowing snow resulting in low visibility. Very cold temperatures and a heavy snowfall are often present in a blizzard, but are not required for a storm to be considered a blizzard. This is because a ground blizzard is possible when snow is already present on the ground. In this type of blizzard, high wind speeds pick the already fallen snow off the ground and blow it, reducing visibility. The National Weather Service officially describes a blizzard as “a storm which contains large amounts of snow OR blowing snow, with winds in excess of 35 mph and visibilities less than ¼ mile for an extended period of time (at least 3 hours).” [55] Although there is not a requirement for temperature, this is one of the main reasons blizzards do not happen in Tampa.




Blizzards often form on the northwest side of an intense snow storm. The very strong winds are formed when the cool air and warm air meet, causing a tight pressure gradient. [56] If snow is not already present on the ground, the storm cloud must have enough moisture and temperatures that are freezing in order to create the snow. Once the snow falls, if the temperatures stay close to freezing, it will remain as snow, and not melt all the way to the ground. [57] In Tampa, temperatures rarely reach freezing, therefore, snow is not a factor, and neither are blizzards. As shown in this chart, the average temperature for Tampa in its’ coldest months is still as high as 59.9F and 61.5F.





Average Temperature (F)



































































































Although blizzards may be fairly common in northern-more states, the location of Tampa closer to the equator, helps keep the city relatively warm, rarely reaching freezing temperatures that snow can form in.









Case Study - Microburst Strikes Tampa (March 14, 2005)


 by Troy Sieburg (sieburg2)



The reflectivity image showing the hail core (pink center) just before the microburst.




On March 14, 2005 a microburst along with a storm hit Tampa and caused damage along a 1.5 mile stretch in the city.  The damage included trees and power lines blown down, roof damage to houses, and windows blown out.  Minor water damage also occurred in a few residences because a storm came through after the windows of multiple buildings had been blown out.[60]  All this damage was done in only about a minute.  This type of damage is typical from this kind of event because microbursts are characterized by very strong winds.  Microbursts are also typical in the south, including Florida, but this event was a little out of the ordinary because microbursts usually form wherever conditions allow thunderstorms to form.  This event occurred about 2 months before stormy season in Tampa starts, so it was a little out of the ordinary for this time of year.




The storm formed in an area of unstable air along the edge of a band of convection which formed around the right rear quadrant of a 250 mb jet streak.[61]  The storm intensified as it reached the shore and was at its strongest as it was moving across Tampa.  The fastest winds were estimated to be about 65 miles per hour.[62]  




Dry air and strong winds above 800 mb could have caused the bow shape that was following the microburst as seen in the reflectivity image.[63]  This aided the intensity of the storm by increasing momentum into the cell, hence, making the microburst stronger.[64]




The microburst was forecast well because meteorologists were warned that such an event may occur when they looked at the sounding pictured below.  In the sounding, the air is very moist and nearly saturated up to about 800 mb.  The air right above this level is very dry and cold as seen on the sounding.  When the warmer air mixes with the colder air above, the large difference in temperature causes the severe downdraft that is present in a microburst.  The level of free convection is 868 mb and the lifted index is -1.0.  This indicates the possibilities of thunderstorms.    





Sounding on the day on which the microburst passed through Tampa.



















Jeffrey Troksa, jtroksa2








Drought is a generally a term to describe a lowing of a geographical region’s water supply. It is mostly due to a decrease or disappearance of rainfall for that region. This weather (or lack of weather) event is particularly dangerous as it effects almost all facets of the economy and ecosystem. Agriculture is hit particularly hard, as plants die off rapidly in prolonged drought periods. Costs rise and economies fall as well. If water supply gets too low, rationing and water conservation laws are often ordered by local governments in order to wait out whatever. [67]




On the surface, Tampa might appear that drought is the least of the city’s worries, due to it being a bay city. However, Tampa has he same vulnerability to drought conditions that most of North America endures. Above is an image of the United States, and the highlighted green area on Florida is where Tampa is located. The green indicates thatTampa region is currently in a drought state, however, due to recent precipitation and positive forecasts, the drought conditions are improving. The current drought is entering its second year. [68] Winter and spring are the driest seasons, while the rain falls generally in the other seasons of summer and fall. [69] The dry winters and springs are said to be caused by the atmosphere phenomena La Niña, which occurs in the Pacific Ocean and is a cooling of water in the Pacific that decreases rain. [70]








It is very difficult to predict a time length for a drought. While Tampa should get rain in the summer, the amount of precipitation and date that it arrives is a mystery at this point, since all we have to go by is historical averages of precipitation.














Leo Rotstein







Tornadoes are violently rotating columns of air that extend from a thunderstorm cloud to the ground.[73] They can have a width anywhere from 50 ft to half a mile and can have winds ranging from 50 to 300 mph.[74] Their strength is measured on what is known as the Enhanced Fujita scale, which ranges from a weak F0 to a powerful F5.[75] Tornadoes occur year round with an average of 800 tornadoes a year resulting in 80 deaths and 1500 injuries.[76] They are typically associated with Supercell thunderstorms, but are possible with any type of thunderstorm. Additionally, in coastal areas like Tampa, tornadoes accompany tropical storms and hurricanes that move overland.[77]





Since a typical tornado forms out of a thunderstorm, the factors necessary for tornado creation are those necessary for severe thunderstorms: high moisture in the mid and lower levels of the atmosphere, highly unstable air, and a lifting force for the air.[78] This sets the conditions for a strong updraft that is associated with thunderstorms and consequently tornadoes. Additionally, strong vertical wind shear is required to create tilting, which creates the strong rotation seen in powerful thunderstorms. The tornado forms inside of these powerful thunderstorms, in the updraft region near the hook echo of the storm.





Tornadoes have been documented in every one of the United States and on every continent.[79] Tampa is no different and faces threats from tornadoes any time the conditions are favorable. Tampa’s thunderstorm tornadoes typically occur in the spring and summer months. At this time tornadoes are quite common in Florida, which has the highest tornado rate in the country.[80] In fact, Tampa-area historical tornado activity is above Florida state average and is 114% greater than the overall U.S. average.[81]  Additionally, tornadoes are possible during hurricane season, which occurs in the late summer and fall.[82] The unique aspect of tornadoes in Tampa is that they are weak and rarely stronger than F2[83]. This is because many of the tornadoes do not come from Supercell storms but from small thunderstorms off the water or from hurricanes. Thus the track of most tornados, and consequently the damage, is usually confined to a small area.




There are also interesting weather phenomena seen in the Tampa area called waterspouts. They are weak tornadoes that form over water and are typically seen in the warm waters of the gulf coast. These frequently occur in the winter months, contrary to when one would expect a tornado in the Tampa area. Their exact formation process in not entirely understood but thought to be similar to regular tornadoes and, in fact, they can move inland and become tornadoes.[84]






Historically tornadoes have not caused much damage in Tampa as they have avoided the downtown area and struck only small outlying areas. Looking at the three most recent cases of tornadoes in the Tampa area, damages were only in the $500,000 to $1 Million range.[86] This is considerably lower than most cases where tornadoes have passed through densely populated areas.



Case Study - 12/25/2006






On December 12, 2006 a small F2 tornado ripped through the Tampa Bay Golf and Country Club and its surrounding subdivision. The tornado, which was part of a line of thunderstorms moving across the eastern gulf coast, had a width of approximately 100 yards and winds of 125 mph. Damages from the tornado were over $1 million but only two injuries occurred. The tornado initially touched down near the clubhouse, traveled for 1 mile, and then ended. On its path it ranged from an F0 to an F2 tornado.




The meteorological conditions across the Florida peninsula that day were primed for thunderstorms and tornadoes. There was a quick developing and intense surface low, which tracked from the western Gulf of Mexico to the Louisiana/Mississippi border the night before the tornado. This low was intensified by an upper level disturbance diving into Deep South Texas. As the low grew more intense, moisture was brought up from the Caribbean in the south and lifted by a cold front. This resulted in a far reaching line of thunderstorms that can be seen in the radar image below. It is important to note that by looking at this radar image no Tornado Warnings were issued for the area.



The line moved into the eastern part of the gulf coast by the morning of the 25th. Here vertical wind shear began to rotate the storms and create turning winds. The wind shear can be seen by looking at the surface and 850mb winds in the sounding. The presence of an unstable atmosphere helped induce these rotating thunderstorms. These storms intensified and eventually produced four tornadoes, one of which struck The Tampa Bay Golf and Country Club.




This tornado did not occur in the usual summer months where strong thunderstorms are common, but instead during the winter season. This is unusual, but not unheard of in the area. The conditions surrounding the tornado were what one would expect in the Tampa area, having come off the water with a powerful line of thunderstorms; not from Supercell storms.[91] This was the reason the tornado was not nearly the strength tornado one would see in Texas or Oklahoma.[92]




While the tornado was weak, it still did a fair amount of damage and made a lasting impact. Nearly 100 homes were damaged. Fifteen were left uninhabitable.[93] There was little to no warning. A severe thunderstorm warning was in effect, but there were no mentions of tornadoes. A first responder in the neighborhood, Janice Bacso was not notified until her beeper went off, even though she lives blocks from where the tornado hit. "I stepped out of my house and into a war zone," she said.[94] Emergency crews were slow to respond, and by the time the Red Cross arrived with supplies, most people had already been assisted by their neighbors. This storm did not result in particular changes to the Golf Club’s tornado safety policies, but it did raise awareness around Florida for the need of better warning systems. Since then recent and stronger storms have compounded the need for better warning systems.[95]






[00]  Rauber, Robert, John Walsh and Donna Charlevoix. Severe & Hazardous Weather. 2nd ed. Dubuque, Iowa: Kendall/Hunt Publishing Company, 2005.
[2]Text Source: Ahrens, C. Donald. Essentials of Meteorology. Belmont, CA : Thomson Learning Inc, 2005.
[15] Rauber, R. M., Walsh, J.E., and Charlevoix, D.J. 2002. Severe and Hazardous Weather.
[24] Edward Bowie  (Nov. 28, 1921). The hurricane of October 25, 1921, at Tampa Fla. Weather Bureau. Retrieved on April 20, 2008 from http://www.aoml.noaa.gov/general/lib/lib1/nhclib/mwreviews/1921.pdf
[30] Rauber, Robert, John Walsh and Donna Charlevoix. Severe & Hazardous Weather. 2nd ed. Dubuque, Iowa: Kendall/Hunt Publishing Company, 2005.
[32] Rauber, Robert, John Walsh and Donna Charlevoix. Severe & Hazardous Weather. 2nd ed. Dubuque, Iowa: Kendall/Hunt Publishing Company, 2005.
[33] Rauber, Robert, John Walsh and Donna Charlevoix. Severe & Hazardous Weather. 2nd ed. Dubuque, Iowa: Kendall/Hunt Publishing Company, 2005.
[34] Rauber, Robert, John Walsh and Donna Charlevoix. Severe & Hazardous Weather. 2nd ed. Dubuque, Iowa: Kendall/Hunt Publishing Company, 2005.
[36] Rauber, Robert, John Walsh and Donna Charlevoix. Severe & Hazardous Weather. 2nd ed. Dubuque, Iowa: Kendall/Hunt Publishing Company, 2005.
[41] Rauber, Robert, John Walsh and Donna Charlevoix. Severe & Hazardous Weather. 2nd ed. Dubuque, Iowa: Kendall/Hunt Publishing Company, 2005.
[42] Rauber, Robert, John Walsh and Donna Charlevoix. Severe & Hazardous Weather. 2nd ed. Dubuque, Iowa: Kendall/Hunt Publishing Company, 2005.


[43] Rauber, Robert, John Walsh and Donna Charlevoix. Severe & Hazardous Weather. 2nd ed. Dubuque, Iowa: Kendall/Hunt Publishing Company, 2005.
[44] Rauber, Robert, John Walsh and Donna Charlevoix. Severe & Hazardous Weather. 2nd ed. Dubuque, Iowa: Kendall/Hunt Publishing Company, 2005.
[48] Rauber, Robert, John Walsh and Donna Charlevoix. Severe & Hazardous Weather. 2nd ed. Dubuque, Iowa: Kendall/Hunt Publishing Company, 2005.
[49] Rauber, Robert, John Walsh and Donna Charlevoix. Severe & Hazardous Weather. 2nd ed. Dubuque, Iowa: Kendall/Hunt Publishing Company, 2005.
[51]Rauber, Robert, John Walsh and Donna Charlevoix. Severe & Hazardous Weather. 2nd ed. Dubuque, Iowa: Kendall/Hunt Publishing Company, 2005.
[67] Rauber, Robert, John Walsh and Donna Charlevoix. Severe & Hazardous Weather. 2nd ed. Dubuque, Iowa: Kendall/Hunt Publishing Company, 2005.                                                                       


[68] http://www.msnbc.msn.com/id/23924100/          
[73 & 74] Rauber, R. M., Walsh, J.E., and Charlevoix, D.J. 2002. Severe and Hazardous Weather. Kendall/Hunt Publishing Company.






































Jenna Vickers, jvicke2

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