Physical Sciences and Mathematics Commons^™

Climatology Of Tornadoes In Kansas, John P. Wasinger, Todd Moore

SACAD: John Heinrichs Scholarly and Creative Activity Days

Recent studies report changes to the climatology of tornadoes in the United States (US). Changes with the most supporting evidence include an increase in the intra- and inter-annual variability, increased concentration of tornadoes in bigger outbreaks, and a geographic shift of the densest tornado activity away from Tornado Alley in the Great Plains and toward the Great Lakes and Southeast regions of the US. Broad, national-level changes are valuable, but they can mask changes occurring at the state and sub-state levels where mitigation efforts are most effective. Kansas is of interest due to its reputation as a hotbed of tornado …

Nashville-Basin Tornadoes: Using Storm Types To Elucidate The Local Climatology And Forecasting Challenges, Morgan Steckler, Kelsey Ellis

Pursuit - The Journal of Undergraduate Research at The University of Tennessee

Early 3 March 2020 was a devastating night for many middle Tennessee residents. A strong EF-3 tornado tore through Nashville at 65 mph, and another EF-4 killed 18 in Baxter and Cookeville alone. Residents of the Southeastern United States are particularly vulnerable to tornadoes. This study aims to better understand local forecasting challenges by looking at the types of storms that produce tornadoes. Storm types, also known as convective modes, divide tornado-producing storms into categories by length, shape, multiplicity, and intensity. Distinguishing storms by these modes allows for a broader understanding of their occurrences and impacts. This study specifically evaluates …

Against The Clock: Uncovering Diurnal Time Interval Decision Differences During Tornado Warnings For Lower Mississippi Valley Residents, Stephen Holden Wooten

Theses and Dissertations

With a higher number of nocturnal tornado events, I surveyed residents of Alabama, Arkansas, Kentucky, Mississippi, and Tennessee (N = 487 for each sample) to determine the time, in minutes, it took to reach a decision on shelter-seeking. I utilized latent class analysis (LCA) to create class memberships, based on diurnal and nocturnal scenarios, to associate with time intervals. Four actors were identified for each scenario: Tech Users, Typical Actors, Non-Reactors, and Social Actors for the day sample, Tech Users, Typical Actors, Passive Actors, and Non-Reactors for the night sample. Time intervals were created and applied to each class. All …

Northern Tornadoes Project. Annual Report 2021 V2, The Northern Tornadoes Project

Project Reports

The Northern Tornado Project’s third year of detecting, assessing and documenting tornadoes and other damaging wind events across Canada saw some interesting extremes – tornadoes in parts of both the Atlantic and Pacific coasts for the first time in decades, an apparent absence of tornadoes on the Prairies over the 60 days with the highest climatological frequency, a record number of significant (EF2+) tornadoes in Ontario, and massive downbursts in NE British Columbia, NW Alberta and SW Northwest Territories associated with an historic ‘heat dome’.

On top of this, the COVID-19 pandemic was still spreading across the country in waves. …

Reveal Wind Loading Of Tornadoes And Hurricanes On Civil Structures Towards Hazard-Resistant Design, Ryan Honerkamp

Doctoral Dissertations

"Extreme winds impacting civil structures lead to death and destruction in all regions of the world. Specifically, tornadoes and hurricanes impact communities with severe devastation. On average, 1200 tornadoes occur in the United States every year. Tornadoes occur predominantly in the Central and Southeastern United States, accounting for an annual $1 billion in economic losses, 1500 injuries, and 90 deaths. The Joplin, MO Tornado in 2011 killed 161 people, injured more than 1000, destroyed more than 8000 structures, and caused $2.8 billion of property loss. Hurricanes occur predominantly on the United States East coast regions and along the coast of …

Examining Terrain Effects On Upstate New York Tornado Events Utilizing High-Resolution Model Simulations, Luke Lebel

Atmospheric & Environmental Sciences

The region at the intersection of the Mohawk and Hudson valleys of New York is characterized by complex terrain. It has been hypothesized that this complex terrain may have an impact on the development and evolution of severe convection in the region. Specifically, previous research has hypothesized that terrain-channeled flow in the Hudson and Mohawk valleys contributed to increased low-level wind shear and instability in the valleys during past severe weather outbreaks. However, a lack of observations in the region prevented this hypothesis from being robustly tested.

The goal of this study is to further examine this hypothesis and complement …

Environmental Discriminators For Significant Tornadoes And Hail In The U.S. Using Proximity Soundings, Cody Michael Converse

Graduate Research Theses & Dissertations

Over the last 50 years, the United States has experienced an increase in severe storm events that produced $1 billion in damages or greater. Much of this loss is attributed to significant tornadoes and hail associated with deep, moist convection. Improving forecasts for these significant events assist in mitigating the impacts of these events. Previous work has identified statistically significant environmental parameters associated with severe thunderstorms, but more research is needed in identifying statistically significant ingredients associated with environments that produce significant tornadoes and hail.

This thesis aims to answer the following question: “Can diagnostics commonly used to forecast for …

Antecedent North Pacific Jet Regimes Conducive To The Development Of Cool Season Continental U.S. Tornado Outbreaks, Jessica Blair

Atmospheric & Environmental Sciences

The occurrence of tornado outbreaks are often associated with considerable societal and economic impacts. The U.S. averages nearly 1000 tornadoes per year that result in 1500 injuries and 80 fatalities, many of which are associated with outbreak days. Additionally, one outbreak alone can cause millions of dollars in property damage. The location of these outbreaks can vary temporally throughout the cool season (September–May) and can vary substantially in terms of their severity.

This study focuses on continental U.S. tornado outbreaks during the cool season and their relation to the state and evolution of the North Pacific jet (NPJ) stream 0–5 …

Incorporating Uh Occurrence Time To Ensemble-Derived Tornado Probabilities, Burkely T. Gallo, Adam J. Clark, Bryan T. Smith, Richard L. Thompson, Israel Jirak, Scott R. Dembek

United States Department of Commerce: Staff Publications

Probabilistic ensemble-derived tornado forecasts generated from convection-allowing models often use hourly maximum updraft helicity (UH) alone or in combination with environmental parameters as a proxy for right-moving (RM) supercells. However, when UH occurrence is a condition for tornado probability generation, false alarm areas can occur from UH swaths associated with nocturnal mesoscale convective systems, which climatologically produce fewer tornadoes than RM supercells. This study incorporates UH timing information with the forecast near-storm significant tornado parameter (STP) to calibrate the forecast tornado probability. To generate the probabilistic forecasts, three sets of observed climatological tornado frequencies given an RM supercell and STP …

Spatial Boundary Detection And Estimation Of Jet Stream As A Key Factor For Tornado Environments, Mingzeng Sun

Legacy Theses & Dissertations (2009 - 2024)

Understanding the impact of spatial patterns and processing features on health is a key element in public health and epidemiology fields. This thesis investigates these fundamental tasks using two approaches: high dimensional Kolmogorov-Zurbenko Adaptive smoothing and spatial boundary identification by rolling variation algorithm.

Differences Between High Shear / Low Cape Environments In The Northeast Us Favoring Straight-Line Damaging Winds Versus Tornadoes, Michael E. Main, Ross A. Lazear, Lance F. Bosart

Atmospheric & Environmental Sciences

High shear / low CAPE (HSLC) environments are common in the Northeast US and can occur at any time of year. Severe weather in HSLC environments is notoriously hard to predict, often catching both forecasters and the general public off-guard. The goal of this project is to help forecasters to identify HSLC environments favorable for severe weather in the Northeast US, and to discriminate between HSLC environments that are supportive of tornadoes versus those that favor straight-line damaging winds (SDW). A 10-year HSLC severe weather environmental climatology was created for the Northeast US (New England, New York, New Jersey, Pennsylvania). …

The Impact Of Past Experience With Tornadoes On Future Decisions, Emily Paltz, Michael Hayes

Honors Theses

Tornadoes are a dangerous threat to public safety. The National Weather Service (NWS), therefore, advises the public to go to an interior room on the lowest level of their houses when a tornado warning is issued for their area. As the NWS Central Region Service Assessment of the Joplin, Missouri Tornado published in July 2011 reveals, however, this is often not the first action taken after learning that there is danger of being hit by a tornado. Rather, people need to seek confirmation from more than one source before following the recommended action. The goal of this research project is …

Impact Of Past Experiences With Tornadoes On Future Decisions In Nebraska, Emily Paltz, Michael Hayes, Matthew Van Den Broeke

UCARE Research Products

The National Weather Service (NWS) advises the public to go to an interior room on the lowest level of their houses when a tornado warning is issued for their area. As the NWS Central Region Service Assessment of the Joplin, Missouri Tornado published in July 2011 reveals, however, this is often not the first action taken after learning that there is danger of being hit by a tornado. Rather, people need to seek confirmation from more than one source before following the recommended action. The goal of this research project is to determine how the number of sources and what …

Spatial Analysis Of Tornado Warning System Understanding And Relationship With Tornado Occurrence, Chesnea A. Skeen

Pursuit - The Journal of Undergraduate Research at The University of Tennessee

Tornadoes present a significant threat to life and property. The National Weather Service watch and warning system warns the public of tornadoes. If these warnings are not heeded by the public, the potential fatalities and destruction of property cannot be minimized. Thus, to prevent further loss of life and property, it is necessary to understand how the public understands the watch and warning system, as well as how they react. This paper aims to understand the correlation between understanding of watches and warnings and the occurrence of tornadoes, as well as how understanding varies spatially. Survey data were collected from …

Using Proxy Records To Document Gulf Of Mexico Tropical Cyclones From 1820-1915, Jordan V. Pino, Robert V. Rohli, Kristine L. Delong, Grant L. Harley, Jill C. Trepanier

Faculty Publications

Observations of pre-1950 tropical cyclones are sparse due to observational limitations; therefore, the hurricane database HURDAT2 (1851–present) maintained by the National Oceanic and Atmospheric Administration may be incomplete. Here we provide additional documentation for HURDAT2 from historical United States Army fort records (1820–1915) and other archived documents for 28 landfalling tropical cyclones, 20 of which are included in HURDAT2, along the northern Gulf of Mexico coast. One event that occurred in May 1863 is not currently documented in the HURDAT2 database but has been noted in other studies. We identify seven tropical cyclones that occurred before 1851, three of which …

Tennessee Tornado Frequency, Vulnerability, And Relation To A Large-Scale Climate Variability, Vincent Marshall Brown

Masters Theses

This work explores the climatologies of isolated tornadoes and tornado outbreaks across the state of Tennessee, a state that in some years experiences more tornadoes than states in the heart of Tornado Alley. Part one assesses tornado frequency characteristics and fatality statistics within 100 km of three major Tennessee cities (Nashville, Memphis, and Knoxville) between 1950 and 2013. Nashville reported the most tornadoes, (426) but Memphis reported the most fatalities. Knoxville and Nashville tornadoes occurred on fewer days, while Memphis tornadoes were spread across more tornado days. Spring was the most active season for tornadoes, but Memphis still experienced approximately …

The Relationship Between Elevation Roughness And Tornado Activity: A Spatial Statistical Model Fit To Data From The Central Great Plains, James B. Elsner, Tyler Fricker, Holly M. Widen, Carla M. Castillo, John Humphreys, Jihoon Jung, Shoumik Rahman, Amanda Richard, Thomas H. Jagger, Tachanat Bhatrasataponkul, Christian Gredzens, Paul Grady Dixon Ph.D.

Geosciences Faculty Publications

The statistical relationship between elevation roughness and tornado activity is quantified using a spatial model that controls for the effect of population on the availability of reports. Across a large portion of the central Great Plains the model shows that areas with uniform elevation tend to have more tornadoes on average than areas with variable elevation. The effect amounts to a 2.3% [(1.6%, 3.0%) = 95% credible interval] increase in the rate of a tornado occurrence per meter of decrease in elevation roughness, defined as the highest minus the lowest elevation locally. The effect remains unchanged if the model is …

An Analysis Of High-Impact, Low-Predictive Skill Severe Weather Events In The Northeast U.S, Matthew Thomas Vaughan

Legacy Theses & Dissertations (2009 - 2024)

An objective evaluation of Storm Prediction Center slight risk convective outlooks, as well as a method to identify high-impact severe weather events with poor-predictive skill are presented in this study. The objectives are to assess severe weather forecast skill over the northeast U.S. relative to the continental U.S., build a climatology of high-impact, low-predictive skill events between 1980–2013, and investigate the dynamic and thermodynamic differences between severe weather events with low-predictive skill and high-predictive skill over the northeast U.S. Severe storm reports of hail, wind, and tornadoes are used to calculate skill scores including probability of detection (POD), false alarm …

Tornado Fatalities: An In-Depth Look At Physical And Societal Influences, Heather Joann Key

USF Tampa Graduate Theses and Dissertations

The purpose of this study is to model and determine significant predictors of tornado death index values, and to investigate these significant predictors and what makes people vulnerable to tornado fatalities through expert interviews. This study also provides an understanding of the study participant’s perceptions of their county’s vulnerability to tornado fatality and demonstrates a true integration of methods and fields by studying geographic, meteorological, and sociological phenomena by use of quantitative and qualitative methods. The study consists of two parts: 1) A quantitative exploration of variables hypothesized to predict Tornado Death Index (TDI) values, 2) A qualitative investigation to …

Tornadoes: Are They Becoming More Frequent And Severe?, Matthew E. Westburg

Natural Sciences Student Research Presentations

Inconsistent record keeping, changes with tornado reporting systems such as the Fujita Scale and Doppler radar, increased public awareness, the use of technology to report tornadoes, and the shifting populations have all played a role in increasing the number of reported tornadoes in Illinois and in the United States. The role that global warming has played in the increased number of tornadoes and their severity since 1950, is still unclear. Several more years of tornado data collecting is needed for us to have a more definitive answer as to whether tornadoes are increasing in frequency and severity and the role …

Adjusted Tornado Probabilities, Holly M. Widen, James B. Elsner, Cameron Amrine, Rizalino B. Cruz, Erik Fraza, Laura Michaels, Loury Migliorelli, Brendan Mulholland, Michael Patterson, Sarah Strazzo, Guang Xing

Publications

Tornado occurrence rates computed from the available reports are biased low relative to the unknown true rates. To correct for this low bias, the authors demonstrate a method to estimate the annual probability of being struck by a tornado that uses the average report density estimated as a function of distance from nearest city/town center. The method is demonstrated on Kansas and then applied to 15 other tornado-prone states from Nebraska to Tennessee. States are ranked according to their adjusted tornado rate and comparisons are made with raw rates published elsewhere. The adjusted rates, expressed as return periods, arestates, including …

Cox, Brittany (Fa 763), Manuscripts & Folklife Archives

FA Finding Aids

Finding aid only for Folklife Archives Project 763. Paper titled “Haunted Places in Brandenburg, Kentucky” written by Brittany Cox for a folk studies class at Western Kentucky University. Paper includes information about haunted locations in Brandenburg, Meade County, Kentucky.

Woolfolk, Dorothy (Gregory) (Sc 713), Manuscripts & Folklife Archives

MSS Finding Aids

Finding aid and scan (Click on "additional files" below) for Manuscripts Small Collection 713. Letter written to Marjorie Clagett, Bowling Green, Kentucky, from Dorothy (Gregory) Woolfolk, Brandenburg, Meade County, Kentucky, in which she describes the tornado that devastated the town on 3 April 1974.

Kesler, Jonathan G. (Fa 201), Manuscripts & Folklife Archives

FA Finding Aids

Finding aid and full-text scan of paper (Click on “Additional Files” below) for Folklife Archives Project 201. Paper: "Day of Disaster: Brandenburg, Kentucky, and the Tornado of April 3, 1974," written by Western Kentucky University folk studies student Jonathan G. Kesler, about the tornado that wreaked death and destruction on Bradenburg, Meade County, Kentucky, on 3 April 1974.

Gis Analysis Of Lightning Strikes Within A Tornadic Environment, Richard Snow, Mary Snow, Nicole Kufa

Publications

Recent research suggests that a maximum rate of lightning strikes occurs at least 15 to 20 minutes prior to tornado formation within a supercell storm. These maxima are associated with strengthening updrafts as they appear in radar measurements. An increase in lightning rates correlates with an increase of shear in the lower part of the storm. In combination with a strong updraft or downdraft, this shear can provide the ingredients for rotation and possibly a tornado. Polarity reversal of lightning around the time of tornado touchdown also has been examined. Thus, increasing lightning flash rates and reversal of lightning strike …

The National Weather Service's Polygon Method: Warning Dissemination Of The Future, Crystal L. Bergman

Mahurin Honors College Capstone Experience/Thesis Projects

The National Weather Service (NWS) is continuously improving its forecasting skills, but forecasters still cannot accurately predict the path of a tornado or a severe thunderstorm. The NWS has developed a new warning system in which the warned area is outlined by a polygon, not a county boundary. The polygon-waming approach is expected to significantly reduce the total square-mile area of warnings not followed by an event, called the False Alarm Area. There are three central issues concerning the failure of the polygon-warning method: I) the size of the counties impacted by a storm, 2) the impact of the new …

A Recommendation For An Enhanced Fujita Scale (Ef-Scale)

United States Department of Commerce: Staff Publications

Background

National Weather Service (NWS) personnel who are responsible for rating tornadoes have expressed frustrations in applying the Fujita Scale in a consistent and accurate manner. Weak links in a structural system or a slow-moving storm sometimes lead to an overrating of a tornado event. Several technical articles suggest that wind speeds associated with some descriptions of damage are too high. For example, a 260 mph wind speed is not required to completely destroy a well constructed house and blow away the debris. The damage occurs at significantly lower wind speeds. Minor et al. (1977) and Phan and Simiu (2003) …

Evolution Of Cloud-To-Ground Lightning Discharges In Tornadic Thunderstorms, Wendy L. Seaman

Theses and Dissertations

Air Force operations are directly impacted by weather on a daily basis. Erroneous forecasts negatively impact mission readiness and consequently cost the government time, in terms of wasted man-hours, and money. Advanced forecast lead-time could make a difference to minimize loss to both USAF personnel and assets. This study examined lightning data from 64 storm events from 1995-2000 in search of unique lightning signatures indicative of tornadic activity. Overall flash rates, percentage of positive flashes, positive and negative peak currents and multiplicity for each case were separated into two categories based on tornado intensity and season of occurrence. Based on …

A Comparison Between The Direction Of Tornado Movement And The Associated 500 Mb. Level Wind Direction, Allen B. Johnson

Journal of the Minnesota Academy of Science

An investigation to ( 1) determine the 500-milli-bar level weather patterns associated with tornadoes moving from northwest toward southeast and from southwest toward northeast and, (2) show the significance of the contrasts between the 500-mb. level weather patterns of the two tornado types. A very high relationship between the direction of the 500-mb. level winds and the tornado direction was substantiated by a coefficient of correlation of +0.88. The typical 500-mb. level low center associated with the northwest to southeast type tornado was located over Hudson Bay about 1300 miles north-northeast of the tornado area. The low center associated with …

Thunderstorms And Tornadoes Of February 1, 1955, Jean T. Lee

NOAA Technical Reports and Related Materials

The purpose of this paper is to describe and illustrate some of the features that are of particular interest in the forecasting of one of the most death-dealing series of convective storms of the 1950s that occurred during the afternoon and evening of February 1, 1955. This series of severe storms included tornadoes, destructive winds, hail, and heavy rain that first struck near Marianata, Arkansas, then roared through Commerce Landing, Mississippi and northern Mississippi. then moved on to near Huntsville, Alabama.

Includes features at the surface, at 850 mb, 700 mb, and 500 mb, and upper air conditions, along with …