weather

We’re Off to See the Blizzard!

Atmospheric Science Students

By Kendall Custer

On March 19th, 2003, residents of the Denver Metropolitan area and the adjacent foothills awoke to a winter wonderland. However, instead of thoughts of stressful work commutes and plans for backyard snowball fights, a sense of cabin fever was settling in. This was the third day of one of the largest snowstorms in Denver’s history. According to the National Oceanic and Atmospheric Administration’s (NOAA) National Regional Climate Center snowfall accumulation database, some residents saw up to thirty inches of snow over four days. As a result, thousands of residents were on lockdown without power and unable to leave their homes.

While the March 2003 blizzard was one of the more memorable snowstorms in the past fifty years, Coloradans are familiar with large blizzards and their inevitable consequences. Other notable Denver storms include the Christmas 1982 blizzard that dropped nearly twenty-four inches of snow, and, more recently, the March 2021 “Pi Day” blizzard that buried the Front Range in twenty-seven inches of snow (data courtesy of the Denver/Boulder National Weather Service [NWS] Weather Forecast Office [WFO]). Large snowstorms like these often result in significant road and travel closures, power outages, and property damage, which are difficult to prepare for and a consequence of inaccurate weather forecasting. Yet, despite what many Coloradans believe, the local meteorologists are not at fault. It is the unfortunate reality of living near large mountain ranges, such as the Rocky Mountains, where radar and satellites struggle to track current weather patterns accurately and topography can change conditions on a dime.

Growing up as a Colorado native who has heard the stories of (and even lived through) these intense blizzards, I developed a passion for mountain meteorology and often wonder: how do we improve weather forecasting for the mountainous terrains that make up our colorful state? What can we as meteorologists do to gather accurate information to help major metropolitan areas mitigate impacts? These questions inspired me to choose the topic of my senior capstone project: investigating the patterns associated with mid-latitude cyclones and how they impact snowfall over Metro Denver and the Foothills.

Mid-Latitude Cyclone Over the Midwestern US as seen from the GOES West Satellite. Photo: NOAA Satellites.

As defined by NOAA’s National Environmental Satellite, Data, and Information Service (NESDIS), a mid-latitude cyclone is a low-pressure system that forms between 30° and 60° latitude, including most of the continental United States, excluding the Gulf Coast and Florida. These pressure systems fall on the “synoptic-scale” (NOAA), meaning their size can range from 620 to 1,500 miles, i.e., the size of one state to multiple at once. If you’ve ever looked at a weather map on the news before, you’ve likely seen a mid-latitude cyclone’s familiar “T-Bone” structure (Schultz & Mass). It consists of a red “L” (for the center of the low-pressure zone), a red line with semi-circles (a warm front), followed by a blue line with triangles (a cold front), and occasionally a purple line with alternating semi-circles and triangles (an occluded front). When looking through the lens of thermodynamics and atmospheric physics, a more complex framework appears, including what is referred to as “conveyor belts”: air bands that vary in temperature, moisture, and density (Lackmann). In a mid-latitude situated over the Midwestern United States, air flows counterclockwise around the low-pressure system. As it does so, warm, moist air is pulled from the Gulf, creating the “warm conveyor belt.” Meanwhile, an east-to-west “cold conveyor belt” of cold, moist air forms ahead of the warm front. When these two belts meet, the warm conveyor belt is quickly forced upward, where the air cools and condenses into clouds before falling as precipitation.

Diagram of air conveyor belt relationship with a low-pressure system. Diagram by Kendall Custer.

In my research, I hypothesize that when a mid-latitude cyclone brings blizzard conditions to Denver, the system’s low-pressure center is most likely positioned over southeastern Colorado. Here, the warm and cold conveyor belts have an easterly flow when they reach the eastern slopes of the Rocky Mountains and encounter upslope forcing, a process where topography redirects wind from horizontal to vertical flow. During this, the air is rapidly cooled, condensing into clouds and producing significant snowfall over Denver and the Foothills.

As mentioned earlier, forecasting these large, heavy snowfall events is challenging in regions like Denver, which is why research like mine focusing on the patterns of meteorological processes is essential. Improving the accuracy and timeliness of numerical weather forecasting can prepare residents (i.e., supply stocking), allow government agencies like the Colorado Department of Transportation to prepare roads by dropping sand/magnesium-chloride to prevent icing, and provide time for energy companies such as Excel to plan for power outages. In the end, these preparations not only keep metropolitan areas like Denver operating during large snowstorms but can save Coloradans’ lives, enforcing the necessity of improved weather forecasting and mountain meteorology research.

References

Denver/Boulder Weather Forecasting Office. (n.d.). Denver’s Fall/Winter/Spring Statistics. National Weather Service. https://www.weather.gov/bou/DenverFallWinterStatistics.

Lackmann, G. (2011). Midlatitude Synoptic Meteorology: Dynamics, Analysis, and Forecasting. American Meteorological Society.

NESDIS. (2018, June 22). Mid-Latitude Cyclone on the First Day of Summer. NOAA. https://www.nesdis.noaa.gov/news/mid-latitude-cyclone-the-first-day-of-summer.

NOAA Satellites. (2019). Powerful Storm System Seen by GOES West [Photograph]. NOAA. https://www.flickr.com/photos/125201706@N06/47380253391.

Schultz, D. M., & Mass, C. F. (1993). The Occlusion Process in a Midlatitude Cyclone over Land. Monthly Weather Review, 121(4), 918-940. https://doi.org/10.1175/1520-0493(1993)121%3C0918:TOPIAM%3E2.0.CO;2.

Synoptic Meteorology. (2023, May 16). NOAA. https://www.noaa.gov/jetstream/synoptic.

I am a Senior Atmospheric and Environmental Science Major with a Meteorology Specialization and a minor in Mathematics. The question of when I first became interested in the weather is greatly debated in my household, ranging from me searching our yard every day for fallen weather balloons after a local TV meteorologist visited my elementary school to when I would beg my dad to pull over so I could take a photo of a cool cloud. Regardless, every childhood fascination with something weather-related led me to today, where I have developed a passion for synoptic-scale meteorology, cyclogenesis, mountain meteorology, severe weather, and investigating the unknown. After graduation, I plan to continue my education by earning my master’s degree, ideally internationally (fingers crossed!), and eventually working in my dream career as an atmospheric researcher. When my head is not in the clouds or my textbooks, I enjoy a range of hobbies, including creative writing, arts/crafts, paddleboarding/hiking with my dog Hershey, and powerlifting.

Hail no! Making Hailstones Smaller One Cloud Seed at a Time

Atmospheric Science Students

By Ashley Walker

Every year the United States suffers from millions of dollars of hail damage to crops, homes, businesses, etc. In 2023, hail resulted in $2.3 billion in damage in the United States alone (NOAA, 2024). Figuring out if we can minimize hail size could make a huge difference. My research focuses on the physics involved in cloud seeding and how this might influence hail formation.

Cloud seeding is a weather modification tool where substances like silver iodide are added to the atmosphere to produce precipitation if moisture is present in that atmosphere. The substances act as cloud condensation nuclei, which helps the formation of ice crystals. If the number of ice crystals were to increase, they would be competing to absorb water. As the water attaches to these particles, it freezes and combines with other droplets to form hail. This increased competition can result in smaller hailstones, which could cause less damage and help communities that are impacted by severe hailstorms. While a lot of research has been done on cloud seedings overall effects, like increasing rainfall, its ability to reduce hail size is not consistent in research. Studies have shown mixed results, some suggesting that cloud seeding does limit hail size, while other studies suggest that cloud seeding has no impact on hail size. These findings emphasize the need to further research to see if cloud seeding is a good tool to reduce hail size.

A very large hailstone cut in half revealing its “rings of growth.” This likely caused severe damage to the surrounding environment. Photo credit: NOAA Legacy Photo; OAR/ERL/Wave Propagation Laboratory (via Flickr).

To explore this, I am using the CM1 Model (Cloud Model 1) to simulate thunderstorms and study how cloud seeding might influence hail formation. CM1 is a numerical model that allows us to simulate weather like thunderstorms, squall lines, and other systems. The model allows the user to adjust different variables like temperature, moisture, and microphysics. This is an ideal tool to study the processes behind hail formation.

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In Hot Water: The Global Change in Hurricane Intensity

Atmospheric Science Students

By Joshua Rowe

Since I was a kid, I have always had an interest in coastal weather. I saw the Pacific Ocean for the first time when I was four years old, and I was in awe of the immense size and natural harmony of the ocean. What sparked my interest in research in this field was the recent global change in tropical cyclone intensity. The warming of the oceans globally has led to an increase in the proportion of intense hurricanes (Holland, 2013). This struck me as immensely important because of the catastrophic impact that tropical storms can have on the lives and properties of anyone living in a coastal region. It is estimated that the average tropical storm in the US causes between seven and eleven thousand deaths per storm, and tropical storms have accounted for between 3.6 to 5.2 million deaths since 1930 in the U.S. (Garthwaite, 2024).

Dramatic View of Hurricane Florence from the International Space Station. Photo: NASA Goddard Space Flight Center, 2024 (CC by 2.0).

The United States is no stranger to tropical storms, and their unpredictability and aggression makes them a daunting task for coastal meteorologists to forecast. Hurricanes are formed as a result of a large amount of water vapor condensing and circulating over warm oceanic areas (Holland, 2014). When water vapor condenses into clouds, it releases large amounts of latent heat, which contributes to the available convective energy in the atmosphere. As the sea surface temperatures rise, the amount of evaporation over the ocean increases and subsequently the amount of available water vapor increases as well. This rise in available water vapor allows for more condensation and latent heat release, which creates a positive feedback relationship that is theorized to be the cause for the increased frequency, intensity, and location of intense hurricanes (Lackman, 2011).

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Thunderstruck: Predicting Dry Thunderstorms

Atmospheric Science Students

By Markus Sonnenfeld

I became increasingly intrigued by wildfires in the western U.S given how crazy the 2020 season was. I have family in both Nevada and California, and the effects of that fire season still have impacts on them today. What I didn’t know at the time was that dry thunderstorms, which produce dry lightning, are a major cause for wildfires in the U.S. A recent example is the August Complex fire in 2020, which burnt about 470,000 acres alone in California, making it the state’s largest wildfire ever. It was created when dry lightning sparked multiple smaller fires that grew into a larger complex of fires. The average cost of fighting wildfires is $1 billion annually with millions of dollars in property loss as well (National Interagency Coordination Center (NICC),ND).

Sunday Gulch in Custer, SD. May 5, 2023. Photo by Markus Sonnenfeld.
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Hail Raiser

Atmospheric Science Students, STS Students

By Madisen Lindholm

As a weather lover, I always fangirl when a big storm rolls through. I love going outside or chasing it (safely) and seeing all aspects of the storm. Sometimes before a thunderstorm that will produce hail, mammatus clouds form. Mammatus clouds are bubbly in appearance, and are considered unique, but we often see them in the Black Hills. These are my favorite clouds due to how unique they are and how telling of the storm components they are.

Clouds against a blue sky. The sky is visible at the bottom of the image and above that dark, bubbly mammatus clouds take up most of the image.
This image was taken last summer from Rushmore Crossing. Up at the top of the image are the dark, bubbly mammatus clouds. Mammatus clouds typically foreshadow hail, and are rare in most areas, but are somewhat common during the summer in South Dakota.

I especially love the aftereffects of a thunderstorm. The stillness in the air, the rainbows, the smell of freshly fallen rain, and the glow of the atmosphere are all amazing to me. It also amazes me how much energy storms produce and use as they race across the plains of South Dakota, dropping rain, wind, hail, and lightning as they go. One storm that particularly amazes me is one that occurred on July 23rd, 2010, in Vivian, SD. This storm produced the largest hailstone ever recorded in the United States (3D printed model pictured above). This hailstone is 8 inches in diameter, 18.6 inches in circumference and weighs nearly 2 pounds! Imagine that hitting your house!

Because I have always loved severe weather, I knew my senior research topic needed to be in that category. I especially find hail fascinating, so I decided to use hail as my main topic. South Dakota summer thunderstorms are known for the hail they bring. From car damage, broken windows, roof damage, livestock casualties, plant damage, and human casualties, hail causes many problems. As a lifelong South Dakotan, there have been many times I have been out and about when suddenly I get a National Weather Service emergency warning about hail, but by that point it is too late to move my car into a safe area. Over the years, it has seemed like hail has increased in frequency and size on a regular basis. For example, last summer it seemed like the majority of storms brought at least pea-sized hail, where just a decade ago I remember hail being a more special occurrence. This struck me as an important hypothesis to address because as climate change becomes worse hail will, too, so I figured it would make for an interesting capstone project.

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To Dust We Shall Return?

Atmospheric Science Students, STS Students

By Lillian Knudtson

Weather affects all people, and it is important for meteorologists to understand a wide range of events to communicate effectively to the public. My capstone is a project designed to dissect a particularly interesting phenomenon, especially to South Dakota. I have chosen to do a case study of a particular dust storm known as a haboob. The storm I am focusing on occurred May 12th, 2022, and it impacted the eastern part of South Dakota. A widespread, long-lived thunderstorm called a derecho created the haboob beginning in the south central portion of Nebraska and traveled north and east towards Sioux Falls. It sustained winds of 80 miles per hour, and the highest recorded winds of the event were 107 miles per hour. This storm is a good example of what is possible and can become a sample case for the future.

Photo of giant reddish-brown dust cloud blowing in from the right side of the image, approaching a playground and a few people watching it.

A haboob is a giant dust storm. It is named after the Arabic word habb, meaning “blown.” This type of storm is most common in the Middle East and Northern Africa, where is it historically arid. But haboobs are also well known in the Southwestern United States and are becoming an occurrence in previously unlikely places as well. Haboobs are created from loose particles that are picked up by strong winds caused by storms like monsoons or derechos sweeping across the surface of the earth. The massive amount of precipitation associated with these events evaporate, which is a cooling process, so cool air called a gust front accelerates out in front of the storm at a fast rate, picking up particles and building a wall of air and dirt. The particles are mostly less than 10 micrometer pieces of dirt, dust, and sand, but they can be as large as a pea, and the wind can pick up other debris along with it. These walls of air and dirt can reach grow to 5000 feet tall and 100 miles wide, and they can move at 60 miles an hour (Eagar, Herckes, Hartnett, 2016). Overall it is a phenomenon that is quite terrifying.

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It Spins Me Right Round: What’s The Big Deal With Tornadoes?

Atmospheric Science Students, Environment, STS Students

By Cory Schultz

If you look at the annual average number of tornadoes per country, the United States reigns supreme, whether we like it or not. And if we look at South Dakota, the state is not without its share of tornadic activity. For instance, as Dennis Todey, Jay Trobec, and H. Michael Mogil write, “A massive outbreak of tornadoes placed the state in the severe weather record book on the evening of June 24, 2003” (19). On that day, sixty-seven tornadoes touched down over a 6-hour period, a single-state record tornado occurrence.

So, you may be thinking to yourself right now, “I live in the Black Hills region of South Dakota. We don’t have a problem with tornadoes.” Well, what if I told you that tornado activity has increased in the Northern Black Hills of South Dakota in the last decade? This increase in activity is not typical for the Northern Black Hills, since only nine tornadoes have been reported in this region since NOAA started gathering tornado data in 1950. What makes this even more alarming is that, of these nine cases, four have occurred in the last decade. This increase is the focus of my capstone with my two-part research question: Do the Northern Black Hills tornadoes that occurred in 2015, 2018, and 2020 have any similar characteristics to each other? Will this help determine when new tornadoes will form over the same region? 

Map of the Black Hills showing tornado tracks and the strength of the tornadoes. A handful are circled west of Lead, SD.
Map of Northern Black Hills tornado tracks and strengths on the EF scale. Red circles indicate tornadoes being researched for this capstone. Source: National Oceanic and Atmospheric Administration
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Is Driving in the Snow Really that Dangerous?

STS Students

By Jake Lindblom

Jake Lindblom is majoring in Atmospheric and Environmental Sciences with a minor in Geospatial Technology. He plans to study atmospheric science in graduate school after earning his bachelor’s degree.

As most Rapid City residents know, snow can be quite a pain to drive in. The roads are treacherous, it’s hard to see, and it just feels dangerous. As a driver, you may presume that more snow on the road equates to more hazardous driving conditions, but does this mean more crashes actually occur? Might you, as a driver, try to avoid those hazardous conditions and choose to stay at home? Furthermore, while you may think you can handle driving in small, frequent snow events, could this be a false confidence?

These are some of the questions I’m trying to answer in my research project. As a student in the Atmospheric and Environmental Sciences Program, I’m interested in operations research, or how to apply what we know about the atmosphere to the “real world” for the benefit of the community. 

But I’m also a snow fanatic, or someone who is irrationally excited about frozen water falling from the sky. Hailing from Olympia, Washington, snow was a rarity, but occasionally we received a good dumping. The largest of these dumps occurred in February 2019, when I measured 22 inches of snow in my backyard!

Snowy scene, with a pond and snow-covered trees.

A pond covered in snow near my house in western Washington during the February 2019 snowstorm. Snowfall totals ranged widely across the area, but my house measured 22 inches… the most I had ever seen in the Puget Sound lowland (photo credit: Jake Lindblom).

This event completely shut down the city. Nobody moved (in fact, my family couldn’t get out of our driveway for a couple days). In a scenario like this, driving would certainly be dangerous, if not impossible. But there are undoubtedly fewer drivers on the road as well. So, should first responders, city officials, and emergency managers expect greater or fewer crashes overall?

In a place like Rapid City, which averages much more snow than Olympia (about 48 inches, actually), the question of how snowfall impacts car crashes is much more pertinent. 

Photo of cars parked with deep snow surrounding them, covering part of the hood on the nearest car.

The November 2019 snowstorm on the South Dakota Mines campus. Snowdrifts were several feet high, as seen here. The storm set a record for the snowiest November in Rapid City (photo credit: Jake Lindblom).

This question seemed like the perfect project for me. It deals with one of my favorite things about the atmosphere (snow) and applies it to a good cause: helping the community understand how snow affects car crash counts. In this capstone project, I hope to identify a causal relationship (if any) between snowfall measurements and vehicle crash counts. I hypothesize that relatively small snowfall events (less than 3 inches measured) may contribute to more crashes than major events (6 inches or more). People may have more confidence in their driving abilities when “only” a few inches of snow cover the ground and may continue on with their daily errands versus when a major snowstorm discourages them from leaving home. If I have time, I’d like to develop a car crash “forecaster” based on expected snowfall and possibly other meteorological variables (like temperature or visibility). But for now, I think I have my plate full!

How Fires Can Create Clouds

Atmospheric Science Students

By Jackson Zito

Jackson is majoring in Atmospheric and Environmental Sciences at South Dakota Mines. He plans on working with wildfires and the development of pyro-cumulus and pyro-cumulonimbus clouds.

When people ask me why I am going to school, I often tell them it’s to get a degree so I can hopefully get a job. After that answer we usually have a conversation like this:

Them: Cool, so what are you learning then? 
Me: Atmospheric and Environmental Sciences. 
They look at me in confusion as if I just spoke a foreign language. 
Me: It’s meteorology. 
Them: Oh, so you’re going to be a weather boy like the one on TV then. 
Me: No, you know there is a lot more you can do with a meteorology degree than just be on the nightly news.
Them: Like what? 
Me: Well, right now I am researching pyro-cumulonimbus clouds. 

Assuming you have a confused look on your face as they often do, let me explain.

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Searching for a Place to Live with the Most Ice and Thunderstorms

Atmospheric Science Students, STS Students

By Steven Slater

Steven is majoring in Atmospheric and Environmental Sciences, and his primary interest is extreme weather.

Ever since I can remember, I enjoyed watching the rare thunderstorms whenever they occurred in Western Washington. I often had to wait a year or more between seeing individual lightning bolts. I often watched The Weather Channel as my main source of weather-related content, whether it had to do with storms or snow. My mind was blown as I watched the reported snow totals rise close to 12 feet for the lake-effect vent in February 2007.

The lowlands of Western Washington don’t receive much snow, so I had to wait for that, too, though it happened more frequently than thunderstorms. I was an advocate for receiving as much snow as possible in the shortest time. The biggest event I experienced in Washington was in December 2008, where I remember playing in ~15 inches of snow at the peak of the event.

A picture containing tree, outdoor, sky, snow.
Washington in January 2012. Photo: Steven Slater.
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