Meteorology Commons^™

Evaluating Rainfall Sensitivity Over Land To Tropical Cyclone Parameters Using Idealized Wrf, Madison C. Yawn

Theses and Dissertations

Tropical cyclones (TCs) are extreme weather events impacting the United States nearly every year. These events often cause severe damage due to the associated responses they produce including storm surge and rainfall, and the accurate estimation of these TC hazards is necessary to support coastal engineering, risk assessment, and emergency management activities. Evaluating TC-driven hazards is often done in combination with numerical models to simulate how environmental interactions alter the physical processes and responses of these storms. The purpose of this study was to simulate synthetic TC events using the Advanced Weather Research and Forecasting (WRF) model to understand how …

Real-Time Enhanced Tornado Warning Product Guidance Based On Tornado Debris Signature Height And Population Density, Alexander Cooke

Theses and Dissertations

This research aims to develop an operational program for enhancing real-time tornado warning capabilities by integrating tornado debris signature (TDS) analysis with population impact assessment. The proposed Python-based tool will ingest Level II radar data to identify and analyze TDS, estimating tornado intensity based on maximum TDS height. For high-intensity tornadoes, the program will project the potential impact area using storm motion vectors and integrate this with population density data. The system will assess whether the situation meets National Weather Service criteria for enhanced warning products, providing forecasters with rapid, objective guidance for critical warning decisions. The program’s performance will …

Influence Of Horizontal Grid Spacing On Numerical Weather Prediction Simulations Of Clear Air Turbulence, Kailah Rose Gordon

Theses and Dissertations

The focus of this research was to analyze the influence of horizontal grid spacing on numerical simulations of kinetic and thermal forced clear air turbulence (CAT) by quantifying uncertainty using a resolution ensemble. Previous studies indicated that microscale (< 1km) spatial resolutions are necessary to resolve turbulent kinetic energy (TKE) with low uncertainty. Six case studies of moderate or greater CAT, from pilot reports, were simulated at six horizontal grid spacings including 1, 2, 4, 8, 16, and 32km using the Weather Research and Forecast (WRF) Model. Results showed that grid spacing does influence the magnitude of uncertainty; however, the relationship between the grid spacings varied with the type of CAT being simulated and the addition of the cumulus parameterization scheme for grid spacings greater than 4km. Overall, higher precision was found between convective resolutions (1-4km), indicating that microscale resolutions are not necessary to precisely simulate TKE for CAT forecasts.

The Role Of Enso Diversity In Modulating Tornadic Activity In The United States, Davis Boyd Newton

Theses and Dissertations

Tornado activity in the United States is influenced by large-scale climate patterns, especially by the El Niño-Southern Oscillation (ENSO). While prior research has explored ENSO’s impact on severe weather, the influence of ENSO flavors, Central Pacific (CP) and Eastern Pacific (EP), on tornadic activity remains understudied. Using tornado records, reanalysis data, and sea surface temperature anomalies, we assess how convective available potential energy (CAPE), wind shear, and jet stream dynamics influence tornado frequency and distribution. Results indicate that CP La Niña years had significant increases in tornado frequency, particularly across the Midwest, Central Plains, and Southeast. EP ENSO years had …

Integrating Case Studies With Meteorologists’ Insight: Assessing Meteorologists’ Perception And Utilization Of Composite Indices, Brianna Marie Salazar

Theses and Dissertations

Meteorologists from sectors, including broadcast, academia, and operations, use derived composite indices such as 0-1km and 0-3km energy helicity index (EHI), effective-layer supercell composite parameter (SCP), fixed-layer and effective layer significant tornado parameter (STP), in addition to other resources, when developing severe local storm forecasts. This study utilizes the Weather Research and Forecasting (WRF) model to create simulations of composite indices for two tornado-producing events: 31 March 2023 and 3 May 1999. With modifications to geographical location, these simulated scenarios are then utilized in the survey to gauge how meteorologists assess where tornado potential is highest. Additionally, a combination of …

Patterns In Tropical Cyclone Intensity And Frequency Since 1960, Ramie E. Thompson

Student Scholarship

Tropical cyclones, also known as hurricanes or typhoons, are defined as organized storm systems that form in the warm waters around the equator (NOAA, 2024). This happens due to the combination of warm waters, light winds, and preexisting weather conditions. In the last 50 years, tropical cyclones have accounted for approximately 800,000 deaths and an economic loss of $1.4 trillion USD due to their resulting damages (WMO, 2024). Research in this field includes studies that encompass a variety of time scales including from 85 to 150 years on a global or regional level and studies that focus on more recent …

2025 May - Tennessee Monthly Climate Report, Tennessee Climate Office, East Tennessee State University

Tennessee Climate Office Monthly Reports

Hi All,

For May 2025, the main weather/climate stories were the continued pattern of severe weather impacting Tennessee as well as Chattanooga recording their wettest May in the 147-year weather history of the city. Starting with the record rainfall in Chattanooga, the Chattanooga airport weather station recorded a total of 12.02-inches of rainfall over May 2025, 8.08-inches above normal and 0.02-inches above the previous record wettest May in 1929. Many other areas of East Tennessee and the Cumberland Plateau also had well above normal rainfall this month, but they were emerging out of a drought from last fall and winter …

Radar Precursors To Severe Weather Reports In Left-Moving Supercells, Eric A. Carothers

Department of Earth and Atmospheric Sciences: Dissertations, Theses, and Student Research

While much research has examined dual-polarimetric signatures of right-moving supercells, very little has been done with left-moving supercells. Given that left-moving supercells are thought to be disproportionate producers of large hail, understanding their internal dynamics is vitally important. This study examines differences and trends in the dual-polarimetric signatures of left-moving supercells to identify precursors to severe weather reports. A dataset of left-moving supercells associated with severe weather reports was created. These storms are processed with an automated analysis algorithm that identifies and quantifies the polarimetric signatures in each storm. A method for analysis of differences and trends in their dual-polarization …

A Synoptic Analysis Of Hurricane Andrew, Alice E. Schipper, Mark R. Sinclair

Student Works

Hurricane Andrew was a historic Category 5 storm that made landfall in southern Florida on the morning of 24 August 1992. Andrew’s landfall brought massive destruction, with entire neighborhoods in the city of Homestead, Florida destroyed. There were 250,000 people left homeless in the US over its entire track, and cost US$25 billion in damage, the costliest hurricane in United States history up to that point. A synoptic analysis was completed to study the tropical and subsequent extratropical phases of this destructive storm. During Andrew’s tropical phase it was found that strong vertical shear initially impeded development. As this dissipated, …

Identifying Saharan Air Layer Events And Their Relationship To Instability And Rainfall Patterns In The Tropical North Atlantic Ocean, Charles H. Dolce

LSU Master's Theses

Every year, strong North African winds across the Sahara loft dust particles and advect them westward within the Saharan Air Layer (SAL). These plumes of dust often reach the Caribbean Sea and can heavily affect regional weather patterns by suppressing convection. When concentrations are high, decreased rainfall can yield negative societal and ecological impacts, potentially leading to drought. The Puerto Rican early rainfall season (ERS), spanning from 1 April through 31 July, overlaps with Saharan dust migration periods, and systematically detecting instances of SAL activity near the island is important for understanding longer-term drought-forcing trends in the region.

Corridors of …

2025 April - Tennessee Monthly Climate Report, Tennessee Climate Office, East Tennessee State University

Tennessee Climate Office Monthly Reports

Hi All,

April was a very active weather month across Tennessee! Consequently, this is one of our longer monthly reports. The main weather and climate stories for April 2025 were the deadly severe weather, extreme rainfall and associated flooding, and record-setting heat that all occurred in the first week of the month. A series of weather systems set up across the central U.S. in the first week of April, with warm, moist air funneled into Tennessee from the Gulf. This pattern produced severe thunderstorms, heavy rainfall, and high temperatures from April 2nd to 6th. The series of storms began on …

Characterizing Rainfall Variability Within A Series Of Storms Over Northern California In February 2017, Parker Jan Malek

Dissertations and Theses

In February 2017, a series of storms with associated atmospheric rivers (ARs) made landfall in the US state of California, dropping large amounts of precipitation over the Sierra Nevada Mountains and their western foothills. The rainfall from these ARs, long, narrow bands of water vapor that transport large amounts of water vapor from the tropics to the mid-latitudes, instigated the near-failure of the Oroville Dam located at the southeastern edge of the Feather watershed outside the city of Oroville in the state's Central Valley. This case study provides a synoptic and mesoscale diagnosis of the drivers of rainfall pulses that …

Urban Heat Dynamics In Pune: The Influence Of Land Cover And Local Climate, Arpit Tiwari, Preethi Nanjundan, Ravi Ranjan Kumar, Ananya Karmakar, Satyaban Bishoyi Ratna

Northeast Journal of Complex Systems (NEJCS)

Urban areas with high population density and extensive infrastructure development have been experiencing an increasing strain on the local heat budget, leading to a surge in heat-related illnesses and discomfort. This study examined the impact of climate and land use as heat islands in Pune, India, from 2012 to 2023 at six different locations representing varying degree of urbanization. Satellite land cover observations revealed that 55.17% of the total area was urbanized in the city itself, which was limited to 44.8% in 2012. This urbanization has significantly impacted the increasing tendency of maximum temperature (T_max; 0.13℃ to 1.63℃ …

2025 March - Tennessee Monthly Climate Report, Tennessee Climate Office, East Tennessee State University

Tennessee Climate Office Monthly Reports

Hi All, March and April were very eventful weather months across the state. We're starting to work through April data but below are the highlights for March. March continued the pattern of extremes in weather that Tennessee has seen in 2025, with high winds and fires, record-setting rainfall, and severe storms impacting the state. Several small to moderate sized grass, brush, and forest fires popped up around the state driven by days with high winds and low relative humidity in early March. One of the largest fires was in Sevier County, where the Pittman Center/Webb Mountain fire burned over 1,000 …

Spatiotemporal Prediction Of Atmospheric Events Through Recurrent Deep Learning Model, Brian W. F. Popick

Theses and Dissertations

The main contributions of this research is to add to the growing library of literature on the use of deep learning algorithms for the spatiotemporal prediction of dangerous atmospheric and hydrologic phenomena. Specifically, we develop novel attention-based and non-attention-based recurrent neural network frameworks to produce short-range sequential forecasts for lightning and tornado occurrences. Additionally, we introduce methods that account for and include error in the model tuning process to generate more reliable models. Furthermore, we have created a lightweight spatiotemporal tornadic prediction dataset that we plan to make publicly available. The first component of this research develops three novel spatiotemporal …

Evaluating Weather Effects On Sortie Generation Using Discrete Event Simulation, Markus Case

Theses and Dissertations

United States Air Force (USAF) operations rely on sortie generation, a complex system involving aircraft maintenance, operational planning, munitions, security forces, and aircrew. Failures in any of these areas can jeopardize a mission, and extreme weather events such as lightning, high winds, and snow further complicate operations. This thesis examines the impact of extreme weather on sortie generation, focusing on developing a data-driven discrete-event simulation (DES) to predict generation timelines and identify high-risk areas. The model allows users to adjust key inputs, including the month, number of aircraft, processing times, and personnel/equipment availability. By simulating real-world conditions, the model helps …

2024 Nhc Verification Report Preview: Atlantic Basin, John Cangialosi, Jon Martinez

National Oceanographic and Atmospheric Administration: Technical Reports and Related Materials

The National Hurricane Center (NHC) is nearing completion of the post-analysis of the 2024 Atlantic and eastern North Pacific basin tropical cyclones. The annual NHC Verification Report uses the post-analyzed information to verify the accuracy and biases of NHC forecasts and real-time model guidance, and the 2024 report will be available in the spring on NHC’s website - https://www.nhc.noaa.gov/verification/. This short review provides some of the preliminary highlights of NHC’s 2024 forecast performance in the Atlantic basin, which is based on a combination of post-analyzed and real time best track data. If interested in the forecast verification for individual …

2025 February - Tennessee Monthly Climate Report, Tennessee Climate Office, East Tennessee State University

Tennessee Climate Office Monthly Reports

Hi All,

February 2025 brought a wide range of weather to Tennessee including severe storms, snow, flooding, and large temperature fluctuations. Warm temperatures in the first week of the month brought a taste of spring after a much colder than normal January across the state, with high temperatures climbing into the upper 70’s for many locations on February 4th. This warm airmass set the stage for severe weather to impact northern areas of the state on February 6th, with six reports of tornadoes (four EF1 tornadoes and two EF2 tornadoes). Cooler and wetter weather then returned to the state for …

2025 January - Tennessee Monthly Climate Report, Tennessee Climate Office, East Tennessee State University

Tennessee Climate Office Monthly Reports

No abstract provided.

The Unique Features Of Typhoon Rai (2021): An Observational Study, Clint Eldrick R. Petilla, Lyndon Mark P. Olaguera, Faye Abigail T. Cruz, Jose Ramon T. Villarin, Hironori Fudeyasu, Ryuji Yoshida, Jun Matsumoto

Physics Faculty Publications

Tropical Cyclone (TC) RAI (2021) made a devastating landfall in the Siargao-Dinagat Islands of the southeastern Philippines on December 16, 2021, causing about USD 942 M in damage, 405 reported deaths and 52 missing. Yet, observational studies on the environmental conditions during TC RAI remain limited, and a comparison with other landfalling TCs were not done. To shed light on the factors that made this TC reach a maximum sustained wind speed (MSW) of 105 kts (194.5 kph) and 915 hPa mean sea level pressure according to the WMO-IBTrACS, this study investigated the meteorological statistics of this TC relative to …

Rain-On-Snow Event Climatology And Hydrological Impacts In The Connecticut River Watershed, Samuel Davidson

Masters Theses & Specialist Projects

Rain-on-snow events, characterized by rain falling on existing snowpack, have the potential to bring about significant hydrological and environmental impacts including snowmelt, flooding, landslides, and other natural hazards. Despite prior evidence suggesting the Connecticut River Watershed has endured socioeconomic and environmental setbacks due to rain-on-snow events in the past, limited prior research has been performed on the role of rain-onsnow events within the region’s hydroclimatology. Gaining a deeper understanding of the occurrence and impacts of such events would provide valuable insights for risk and water resource managers. The purpose of this research was to create a climatology of rain-on-snow events …

Statistical Analysis Of Climate Trends And Variability In Tarrant County Using Annual, Decade, And Three-Decade Time Periods, Quinnton Debolt

Earth & Environmental Sciences Theses - Archive

This study is a statistical analysis of climate trends within the Dallas-Fort Worth metroplex according to several time-scale models to understand how the climate for the locality has changed and to provide a basis for projections of what future climate might look like. Trends in mean temperature and precipitation for North Central Texas generally correlate with corresponding global trends linked to natural variability and anthropogenic-induced climate change. Temperature rises in this region annually by 0.08°C and by 0.22°C for a three-decade average. Seasonal increases in three-decadal averages of temperature for North Central Texas relative to the average of the reference …

Capturing High-Impact Weather In A Fine-Scale Climate Simulation Using The Model For Prediction Across Scales - Atmosphere (Mpas-A) V 7.0, James George Digilio Jr.

Graduate Research Theses & Dissertations

The research a long-term, high-resolution (15-km) global simulation using the Model for Prediction Across Scales – Atmosphere (MPAS-A) version 7.0, a community atmospheric modeling platform with unique capabilities for weather and climate research. This simulation spans 30 continuous years, covering water years 1990 through 2019 (i.e., 1 October 1989–30 September 2019) and is initialized with the European Centre for Medium-Range Weather Forecasts Reanalysis v5 (ERA5). Sea surface temperatures and sea ice are prescribed and updated daily using the fine-scale (0.05°) Operational Sea Surface Temperature and Ice Analysis (OSTIA). To date, this is one of the few high-resolution MPAS-A simulations at …

Climate Change Effects On The 2022–2023 High Impact Series Of Atmospheric Rivers Along The United States West Coast, Hunter Martinez-Buehrer

Graduate Research Theses & Dissertations

Atmospheric rivers (ARs) are long, narrow bands of water vapor transport that are commonly associated with a low-level jet ahead of a cold front of an extratropical cyclone. When multiple ARs occur in succession of one another within a certain aggregation period, it is known as an AR family. ARs and AR families are important to the U.S. West Coast—and especially California’s—hydroclimate, providing both beneficial and hazardous precipitation to the region. Recent studies have suggested that not all ARs and, thus, AR families, respond similarly to a warming climate. Therefore, it is critical to better understand how climate change impacts …

Improving Understanding And Connections For Preparedness, Mitigation, Response, And Recovery For Tornado And Straight-Line Wind Events In Virginia: Summary Of The Inaugural Virginia Tornado And Straight-Line Wind Summit, Wie Yusuf, Monica Arul, Joshua Behr, Kaleen Lawsure, An Huy Pham, Henry Attivor

School of Public Service Faculty Publications

Background

The Virginia Tornado and Straight-Line Wind Summit, the first of its kind in the Commonwealth, was held on October 15, 2025 in Isle of Wight County, Virginia. The Summit had several goals, including:

• Understanding Virginia’s wind risk and learning the science behind it.
• Hearing lessons learned from emergency managers who have experienced extreme wind events.
• Learning about practical steps to prepare, mitigate, and respond to severe wind events.
• Learning best practices for timely and actionable communication with the public before and after events.
• Strengthening interagency coordination and connecting with others to share resources, align priorities, and coordinate resilience planning. …

High-Altitude Balloon-Launched Uncrewed Aircraft System Measurements Of Atmospheric Turbulence And Qualitative Comparison With Infrasound Microphone Response, Anisa Haghighi

Theses and Dissertations--Mechanical and Aerospace Engineering

This study explores the use of a balloon-launched uncrewed aircraft system (UAS) to measure atmospheric turbulence in the troposphere and lower stratosphere using both wind velocity measurements and infrasonic acoustic energy. The UAS, a glider configured for autonomous descent along a predefined trajectory, had on board, in situ sensors to capture thermodynamic and kinematic atmospheric parameters. Additionally, it carried an infrasonic microphone to evaluate its potential for remotely detecting clear-air turbulence by capturing infrasonic waves. The system’s performance was assessed over the course of three test flights conducted in New Mexico, USA, in 2021. The descent enabled high-resolution profiling, with …

Comparing Surface Currents Near The Mouth Of Three Bays Along The U.S. East Coast: Chesapeake Bay, Delaware Bay, And New York Bay, Tal Ezer, Teresa Updyke

CCPO Publications

Monthly surface currents at 2 km resolution near the mouths of three U.S. east coast bays were obtained from high-frequency radars (Coastal Ocean Dynamics Application Radar, CODAR) during 2012–2024. The currents near these bays, the Chesapeake Bay (CB), the Delaware Bay (DB) and the New York Bay (NB) were analyzed to infer similarity and differences, as well as potential common forcing from regional and basin-scale factors. The contribution to flow variability from local and remote forcing is evaluated by comparing surface currents with (a) river discharges into each bay, (b) with local and regional winds, and (c) with the North …

Spatiotemporal Evolution Of Surface Water Quality And Driving Factors Across Varying Levels Of Human Interference In A Major Subbasin Of The Yellow River Basin, China, Longmei Xie, Ruizhong Gao, Xixi Wang, Limin Duan, Lijing Fang, Hui Tong, Chang Yue, Tingxi Liu

Civil & Environmental Engineering Faculty Publications

Study region

The Dahei River Basin, a sub-basin of the Yellow River Basin, was selected for this study. Encompassing population centers and villages in Inner Mongolia, it supports vital ecosystems and underscores the need to address its unique challenges in water management and protection.

Study focus

This study examines surface water quality dynamics in the Dahei River Basin, a key aspect of sustainable water management. Predicting spatiotemporal variations and driving factors remains challenging. Using 2013–2023 datasets on water quality, hydrology, and meteorology, the composite pollution index (CPI), ANOVA, and generalized additive models were applied to provide insights for effective management. …

A Wall Of Smoke: Understanding The Drivers Of The June 2023 Canadian Wildfire Smoke Event For New York City, Gregory S. Randazzo

Dissertations and Theses

The 2023 Canadian wildfire season was notable for its extent and the dense smoke it produced. Motivated by the resulting air quality impacts in the New York City region, we explore how the total particulate matter output from the Quebec fires influenced PM2.5 concentrations downstream in New York City. Using injection height data from the Regional Advanced Baseline Imager + VIIRS Emissions dataset, we relate the tropospheric injection heights of the fires with the broader synoptic context and surface PM2.5 concentrations. Using data from the NYS Mesonet Profiler Network, radiosondes, and ERA5 reanalysis, we document the connection between an anomalous …

Understanding The Dynamical Mechanisms Governing Northern Hemisphere Wintertime Persistent Flow Regimes And Their Associated Extreme Weather Events, Tyler Christopher Leicht

Electronic Theses & Dissertations (2024 - present)

Weather regimes are characterized as patterns of low-frequency variability in the middle to upper troposphere of the extratropics. Weather regimes can also be linked to variations in surface weather, making the study of weather regimes a bridge between traditional synoptic-dynamic meteorology and subseasonal-to-seasonal variability. This dissertation identifies and categorizes persistent flow regimes (PFRs), analyzes the dynamics underpinning PFR formation, identifies the linkages to atmospheric teleconnections, and examines the occurrence of surface weather extremes before and during PFRs.

PFRs are identified from 1979–2022 and grouped into five clusters using k-means clustering, which then allows for time-lag composite analysis to determine the …