Conference Spotlight

Tornado Risks: Perceptions and Realities

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A session spotlight from the 31st Conference on Severe Local Storms

By Katie Pflaumer, AMS Staff

The session “Perception and Risk Associated with Severe Weather” at the 31st Conference on Severe Local Storms highlighted the interactions between severe weather and societal impacts. Here are a few takeaways.

Tornado impacts are increasing across the United States–despite variation in where tornadoes hit. A presentation by Stephen Strader (Villanova University) highlighted the importance of considering all factors to understand tornado impacts, not just climate. Using 40 years of observational data, plus a statistical model depicting changes in societal factors, researchers found that increased housing and population growth in tornado-prone areas is a key driver of increased tornado damage/human risk. 

While the number of days with tornadoes is trending down in the U.S. Southern Plains and trending upward in the mid-South; the likelihood of tornado damage has increased in both regions due to increased human occupation. However, the combination of tornado increases with population growth and spread has tripled tornado impact potential in the mid-South since 1980, surpassing the Southern Plains. Strader noted that stricter enforcement of building codes, investments in tornado shelters and safe rooms, and public education could help mitigate tornado damages–if scientists can get across the message that human factors matter.


“We have to get away from this idea that climate change is a cause of a disaster … climate change is a contributor to a disaster, not a cause. [Disaster] is inherently linked to societal factors. … With environmental changes and exposure changes/housing growth, you see an increasingly disaster-prone society.”

—Stephen Strader

Graphic from: Strader, S.M., Gensini, V.A., Ashley, W.S., and A.N. Wagner (2024) “Changing Tornado Environments Vs. Changing Societal Vulnerability and Exposure.” (Poster presented at 31st Conference on Severe Local Storms, October 21.) Originally from Strader et al. (2024), “Changes in tornado risk and societal vulnerability leading to greater tornado impact potential.” NPJ Natural Hazards, 19 June. https://doi.org/10.1038/s44304-024-00019-6

Wireless Emergency Alerts are critical—and confusing—for Spanish speakers in the U.S. Southeast. A study presented by Joseph Trujillo-Falcón (University of Illinois) found that Spanish-language wireless emergency alerts (WEAs, phone notifications about severe weather) from the National Weather Service are crucial safety tools. For some tornado survivors in Kentucky, for example, the WEA had been their only trigger to get to safety. In-depth conversations with 27 Spanish speakers from across the U.S. found that WEAs were highly respected and useful, yet needed some redesign to avoid confusion. For example, the Spanish translation of the NWS acronym (SNM) called to mind medical conditions or kink. The word “proyectiles” (projectiles), used to warn about airborne debris, evoked war zone imagery rather than weather. Using the word “aviso” for “warning” struck many as less urgent than the term “alerta.” In addition, 360-word warnings (versus those of 90 words or less) helped readers better understand what was going on and what to do in response. This was especially important for people who hadn’t encountered a tornado in their country of origin. Direct links to information and instructions on how and where to shelter were also seen as key, especially in areas with many mobile or manufactured homes.

“The information source that I take most seriously as a recently arrived immigrant are WEAs. Since everyone gets it at the same time, if one ignores it, the other reads it.”

—Gabriela, Venezuelan immigrant who has limited English proficiency (Trujillo-Falcón 2024).

People want different forecast information as a threat evolves. A study presented by Makenzie Krocak (National Severe Storms Laboratory) analyzed data from the Severe Weather and Society survey to determine what information members of the public want and need at different times in relation to weather threats. They found that respondents’ priorities changed over time. In longer time frames (e.g., three days in advance) survey respondents overwhelmingly ranked location information and event probability as the most valuable information; people wanted to know, ‘Should I prepare for severe weather to occur in my area?’ A day to an hour in advance, people wanted to know about the timing of the event, as well as its potential severity. In the warning time frame (60 minutes or less) their desire for information about potential impacts and necessary protective actions increased.

For additional insight, the researchers painstakingly categorized, geo-located, and analyzed 9000+ social media comments from the National Weather Service Facebook and Twitter/X accounts before and after severe weather events. A poster presented by undergraduate student Emily Allen (University of Louisiana Monroe) delved into this side of the equation.

Emily Allen with her poster, “Assessing Public Information Needs Leading Up to Severe Weather Events.” (E.A. Allen and M. Krocak, 2024)

Three days out from an event, commenters largely asked about the chance of an event happening, but for nearer time frames, location became the dominant question—i.e., ‘Will this hit my specific area?’ Krocak emphasized the need to include very clear landmarks in warning graphics to help people find their location. She also noted that certain groups still require information about protective actions to take—especially those with the least experience dealing with a particular hazard.

Making severe weather products usable and understandable. Two presentations dealt with public perceptions of evolving probabilistic weather forecast information—that is, communicating changes in severe weather risks across time and geography. 

Christopher Wirz (NSF NCAR) presented preliminary results of a study about public perceptions of evolving probabilistic tornado forecasts and warnings. On average, respondents’ sense of risk was about the same as for a deterministic (e.g., warning vs no-warning) forecast; most were likely to be on high alert during a tornado warning in any case, and not underestimate their risk. However, there were differences in how participants responded based on where they were located relative to a given warning polygon. For example, some felt they were in more danger if they were ‘in front’ of the warning polygon, despite the graphics showing equal tornado risk in other directions. Warn-on forecasts—alerts issued when a significant risk is predicted, often long before a tornado is detected by radar—were seen as less actionable by some, but others appreciated knowing to ‘keep an eye out.’ Overall, the study found that members of the public don’t take probabilistic information at face value—rather, they interpret it based on context, including existing local knowledge and other warning products they encounter. In addition, for half of the respondents, level of trust in a forecast didn’t change when they received more/updated information, because trust was instead based on how much they trusted the source of the forecast.

Kristin Calhoun (NOAA National Severe Storms Laboratory) presented about new products and communications that are in development to help NWS forecasters and emergency managers use storm-based probabilistic hazard information (PHI) in the severe weather watch-warning timeframe. These included PHI tools layered with threats-in-motion (TIM) information, in which warning polygons are moved (and removed) with the motion of the storm, helping downstream areas prepare sooner and allowing those for whom danger has passed to redeploy their resources more strategically; potential new protocols for the NOAA/NWS Storm Prediction Center, rather than local weather forecast offices, to add or remove an area from a watch/warning once the threat has passed; a blended PHI plus warn-on forecast product that can help emergency managers plan better by seeing storms in motion along with trends in likelihood and potential impact; and a new product based on SPC’s ‘Mesoscale Discussions,’ created by local NWS forecasters and called ‘Local Discussions,’ with an increased focus on potential impacts, timing, and location of hazards versus highly technical information.

Photo: National Severe Storms Laboratory, Watch-to-Warning Experiment.

Social pressure may impact campus tornado safety. Alicia Klees (University of Illinois at Urbana-Champaign) presented work conducted largely by undergraduate student Kyla Wolski that has implications for student safety. The University of Illinois’s Illini-Alert system warns students when tornado threats are approaching; most students are aware of the alerts, and most have experienced a tornado warning before. Students were asked in a survey what they would do if they were in a vulnerable location—such as a fourth-floor classroom with glass windows—and received a tornado warning. 75% said they would change their location to seek shelter. However, when a hypothetical professor kept teaching through a tornado warning (as some faculty reportedly did during the last real tornado warning on campus), 22% of students who had planned to seek shelter said they would probably stay in class. These students said they trusted the professor’s judgment—yet professors do not receive extensive formal training on tornado safety. Klees recalled an anecdote from a student in which one faculty member remarked, “I don’t hear the sirens anymore, so it’s fine.”

In addition, most students did not view tornadoes as a major risk, and most were unaware that tornadoes could happen at any time of year. Klees identified future collaborations with Emergency Management to survey faculty and TAs on tornado warning response, with the goal of keeping students safe.

If you are registered for the 31st Conference on Severe Local Storms, you can view the full session recording at this link.

About the 31st Conference on Severe Local Storms

The American Meteorological Society’s 31st Conference on Severe Local Storms takes place 21-25 October, 2024, in Virginia Beach, VA, and online. The conference is the premiere gathering for scientists, forecasters, educators, and communicators engaged in all aspects of work related to hazardous deep convective weather phenomena. Attendees present and discuss cutting-edge research regarding the analysis, prediction, communication, and theoretical understanding of the structure and dynamics of severe thunderstorms, including their associated hazards of tornadoes, damaging winds, large hail, lightning, and flash floods. View the conference program here.

Can Decarbonizing the Electric Grid Help Avert Climate Catastrophe?

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Photo by Harry Cunningham @harry.digital: https://www.pexels.com/photo/photo-of-wind-turbines-under-cloudy-sky-3619870/

A Presidential Session Spotlight from the AMS 104th Annual Meeting

By Katie Pflaumer, AMS Staff

Significantly reducing greenhouse gas emissions requires transitioning primarily to carbon-free sources for energy generation, but many challenges stand in the way. What are these challenges, and how can the weather, water, and climate sector help meet them?

A Presidential Session at the 104th AMS Annual Meeting addressed those questions with panelists Debbie Lew (Executive Director at ESIG, the Energy Systems Integration Group), Alexander “Sandy” MacDonald (former AMS President and former director of the NOAA Earth Systems Research Laboratory), Aidan Tuohy (Director of Transmission Operations and Planning at EPRI, the Electric Power Research Institute), and Justin Sharp (then Owner and Principal of Sharply Focused, now Technical Leader in the Transmission and Operations Planning team at EPRI). Here are some key points that arose from the session, titled, “Transition to Carbon-Free Energy Generation,” introduced by NSF NCAR’s Jared Lee, and moderated by MESO, Inc.’s John Zack.

Key Points

  • Decarbonizing the electric grid is key to reducing U.S. greenhouse gas emissions.
  • Wind and solar are now the cheapest forms of energy generation; adoption is increasing, but not fast enough to catch up with the likely growth in demand. 
  • Energy demand is rapidly increasing, driven by the expansion of data centers, AI applications, crypto mining, and the electrification of transportation and heating. Hydrogen production might greatly increase future loads. 
  • “Massive buildouts” of both renewable energy plants AND transmission infrastructure are required to reduce emissions. 
  • A reliable and affordable power system with large shares of wind and solar generation requires accurate historical weather information to inform infrastructure buildout, and accurate forecasts to support operations. 
  • To avoid expensive infrastructure that’s only used during peak times, electricity pricing must incentivize consumers to avoid excessive use during periods of high demand. This requires accurate weather forecasting. 
  • Connecting the three main national grids together into a “supergrid” could improve transmission and grid flexibility, significantly reducing emissions.

The need for carbon-free energy is urgent

Greenhouse gas emissions are still increasing sharply. In response, global temperatures are rising faster than even the most pessimistic models would have predicted a few decades ago, noted Lee in his introductory remarks to the panel. The U.S. is the second largest global carbon emitter, despite having a much smaller population than the other top emitters, China and India.

If we don’t solve the greenhouse gas problem by mid-century, warned MacDonald, we will soon hit 700 ppm of carbon dioxide in the atmosphere. If that happens, “We’re back to the Miocene era,” he said, referencing an exceptionally hot period around 12.5 million years ago. “Northern Hemisphere land temperatures will be 11 degrees Fahrenheit warmer. Arctic temps will be 17°F warmer, which is probably going to launch a huge permafrost thaw … The ocean will be 80% more acidic. So we are in an urgent situation.”

What’s the path to a more sustainable future? Decarbonizing the grid.

The energy sector is one of the top sources of U.S. emissions—and reducing emissions there will have knock-on effects in buildings and transportation. Lee noted that wind and solar power have dropped dramatically in price, becoming the cheapest forms of energy generation available. This has led to an increase in adoption: renewables are now second only to natural gas in terms of electrical power generated in the United States. Yet natural gas is still growing fast, and still far exceeds the use of renewables.

Therefore, Lew said in her talk, we need “massive buildouts of [wind, solar, and battery] resources … doubling or even tripling the amount of installed capacity. We’re going to be electrifying buildings, transportation, industry [and] massively building out transmission and distribution networks … And we’re going to be using fossil fuel generators for reliability needs.” Doing this could get us to 80-90% fossil-free energy production.

Bridging the gap

But what about that last 10–20%?

“We need some kind of cost-effective, clean, firm resource” to fill in the gaps and act as a bridge fuel—a resource that’s available 24/7 no matter the weather or season—said Lew. This resource might end up being hydrogen, advanced nuclear energy, or even green bioenergy with carbon capture and sequestration to offset emissions from natural gas. “We need all options on the table.”

Weather? Or not?

Trying to transition to renewables without incorporating reliability and resilience will lead to blackouts and power outages, Tuohy noted. These would have major economic consequences and reduce the political viability of renewables, as well as leading to unjust allocation of energy.

A resilient grid, he said, requires enough energy production to meet future demand; adequate transmission and delivery infrastructure to meet future needs and to balance supply with demand moment-to-moment every day; reliability despite constant shifts in energy production; and the ability to prevent a problem in one place from causing cascading outages across the system. 

Making a new, wind- and solar-dependent grid truly work means balancing—and forecasting—energy availability and demand across the nation, accounting for the current and predicted weather at each solar and wind energy site, as well as how climate change will affect resource availability. This means a massive meteorological infrastructure must be created.

Read our upcoming post from Justin Sharp to learn more about how weather and renewable energy must work together.

“[This is] an operational need, not a research project … There’s an imperative to have dedicated, accurate, and expertly curated weather information to support the energy transition.”

—Justin Sharp

Uncertainty

Demands on the grid are now subject to extreme variability, not just from weather and climate, Tuohy said. For example, demand projections from 2022 versus 2023 were radically different because of new energy-intensive data centers coming online.

“We’ve gone from a kind of deterministic system — [in which we] had good sense of, our peak demand’s going to happen in July—to a far more stochastic and variable type, both on the demand and the supply side,” said Tuohy. We have a lot of data and computational tools, but we must be able to bring those datasets together effectively so we can analyze and predict change. “We need to … develop tools that account for [uncertainty].”

Changing behavior

The infrastructure required for the necessary expansion of renewable energy generation will be expensive. Keeping the cost manageable means not wasting money to build extra infrastructure that’s only useful during times of peak demand. That means we need to avoid high peaks in energy use.

We know that people can be a lot more conscientious about energy consumption if they think it will save them money. Yet many consumers are currently sheltered from the financial consequences of overloading the grid. “There’s tremendous flexibility in load if you … expose consumers to better price signals,” Lew said.

Consumers could be financially incentivized, for example, to choose off-peak times to turn on a heater or charge an electric vehicle. Such programs should be carefully designed to minimize negative impacts on vulnerable consumers, but the fact remains that to keep those consumers safe, the climate crisis must be confronted.

Supergrid to the rescue?

The main problem with a renewable energy grid, the speakers acknowledged, is transmission—both connecting new generators and moving energy based on supply and demand. “You’ve got to be able to move wind and solar energy around at continental scales,” said MacDonald. A study by ESIG suggested that simply adding a 2-gigawatt transmission line connecting the Texas power grid with the Eastern U.S. power grid would effectively act like 4 GW of extra electricity generating capacity across the two regions, because their grids experience risk and stress at different, complementary times.

A 2016 paper MacDonald and colleagues published in Nature Climate Change suggests that U.S. electricity-sector carbon emissions could be decreased by 80% — with current technology and without increased electricity costs — if the United States can implement a “supergrid.” That means connecting all three major electrical grids currently serving the continental United States. When it’s sunny in San Jose and snowing in Cincinnati, you could transmit solar-produced energy to keep Ohio homes warm, rather than generating extra power locally. 

It will take a lot of effort, but “if we [start implementing a supergrid] now, in a 40-year transition, we can preserve the environment we have,” MacDonald said. “If we wait until the 2040s, we are basically going to devastate the planet’s life for thousands of years.”

You can view all the AMS 104th Annual Meeting presentations online. Watch this Presidential Session.

Photo at top: Harry Cunningham on Pexels (@harry.digital)

How is Weather Research Changing?

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A 2024 AMS Summer Community Meeting highlight

The AMS Summer Community Meeting (SCM) drew exceptional attendance and engagement this year as people across sectors helped inform a major upcoming report on the Weather Enterprise. The AMS Weather Enterprise Study will provide a comprehensive picture of the shifting landscape of weather-related fields to inform our joint future. At the 2024 SCM, working groups discussed what they’d found about key issues facing the enterprise, and asked for feedback from the community. 

Here are a few takeaways from the Research Enterprise working group, as reported by Daniel Rothenberg of Brightband.

Photo courtesy of Daniel Rothenberg.

How has the weather research landscape shifted in the last decade or so?

Two of the most important shifts have been a movement of exploratory and applied research from the public to the private sector, and the rise in importance of “data science” and other hybrid roles blending a mixture of domain expertise and broader engineering and technical skills. 

Possibly the biggest example of these shifts coming together has been the advent of AI-based weather forecasting tools, although it also shows in trends such as the rise of private companies operating earth observation platforms.

What were the principal themes that came out of your working group’s discussions?

One major theme we discussed was the balance of responsibilities across the traditional weather enterprise. Initiatives such as building and launching satellite constellations or developing new weather models were at one point solely within the remit of the public sector (due to complexity and cost), but are now commonly undertaken by the private sector – sometimes even at start-up companies.

This re-balancing opens as many opportunities as it does challenges, and leads to another major theme: how we can best prepare for the workforce needs of today and tomorrow. Meteorologists will increasingly need to apply technical skills such as software development and data science alongside ones from the social sciences; preparing our current and future workforce for these demands will be a challenge in its own right.

A third major theme is that the weather enterprise is getting bigger. We’re not just a community of meteorologists anymore. Increasingly, critical work related to weather, water, climate, and their impacts on society is being undertaken beyond the traditional boundaries of our enterprise. There is a significant opportunity to improve society’s resilience if we as a community are able to build relationships with the new institutions working on these issues in a collaborative, interdisciplinary manner.

What are the main challenges you have identified?

Better accounting for how we ought to invest limited – and declining – federal resources will be a significant and contentious challenge, only complicated by the shifts in priorities and capabilities across the enterprise.

Those shifts motivate a second key challenge, which is clarifying who in the enterprise is accountable for, or has ownership over, certain areas. For example, NOAA makes available nearly all of the observations used in its operational forecast models, with some exceptions for proprietary data from commercial entities. But as more private companies try to sell data to NOAA, how will this balance hold? What if those private companies move towards selling actual weather modeling capabilities or services – perhaps a proprietary AI-based weather model – to the government? In the case of expanding commercial data purchases, who is responsible for maintaining and improving our data assimilation capabilities? 

Coordinating many actors across the enterprise, in a manner that most effectively serves our mission to society, will be a key challenge we must navigate in the coming years.

What preliminary recommendations or future directions have you discussed?

Our tentative recommendations revolve around building robustness. We encourage academic organizations who train our future meteorologists to consider how to prepare these students to work in a multidisciplinary capacity, and to embrace data science skills. Not everyone needs to be an interdisciplinary scientist, but it’s vital that our students learn how to apply their deep domain knowledge as part of a team of such individuals.

We also acknowledge that the rise of AI/ML techniques is changing the demands of our computing and data infrastructure. Not only must our workforce learn to adapt to these technologies, but we must consider how the enterprise will support enabling them: for example, by ensuring that in addition to large, traditional high-performance computing resources, we provide access to GPUs and similar tools. As part of this re-evaluation, we must evolve the ways in which we as a community define our priorities for federal research funding

What did you hear from the community at the SCM?

We thank the community for the warm reception to our assessments at the Summer Community Meeting. Many of the themes we touched on – the re-balancing of capabilities across the enterprise, the emergence of AI/ML and its implications, as well as core workforce development concerns – were echoed across many other working groups, underscoring their importance.

Within our group, we also discussed the growing importance of convergence science, which was echoed several times throughout the meeting. Convergence science, which involves coordinating diverse, interdisciplinary research teams with real stakeholders to solve societally relevant problems, is likely to be an important mechanism of translational research in the future, but we (and others at the meeting) identified a need for federal agencies to devote more resources earmarked for this sort of work in order to complement traditional, siloed funding programs.

Want to join a Weather Enterprise Study working group? Email [email protected].

About the Weather Enterprise Study

The AMS Policy Program, working closely with the volunteer leadership of the Commission on the Weather, Water, and Climate Enterprise, is conducting a two-year effort (2023-2025) to assess how well the weather enterprise is performing, and to potentially develop new recommendations for how it might serve the public even better. Learn more here, give us your input via Google Forms, or get involved by contacting [email protected].  

About the AMS Summer Community Meeting

The AMS Summer Community Meeting (SCM) is a special time for professionals from academia, industry, government, and NGOs to come together to discuss broader strategic priorities, identify challenges to be addressed and opportunities to collaborate, and share points of view on pressing topics. The SCM provides a unique, informal setting for constructive deliberation of current issues and development of a shared vision for the future. The 2024 Summer Community Meeting took place August 5-6 in Washington, DC, and focused special attention on the Weather Enterprise, with opportunities for the entire community to learn about, discuss, debate, and extend some of the preliminary findings coming from the AMS Weather Enterprise Study.

Bumpy Flight into Hurricane Ian Births a New Metric for Turbulence

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Airplane over hurricane

A research spotlight from the 36th Conference on Hurricanes and Tropical Meteorology

NOAA’s WP-3D Orion “Hurricane Hunter” aircraft are no strangers to turbulence. Reconnaissance flights through hurricanes are by definition a tad bumpy.

A viral video taken aboard the Hurricane Hunter “Kermit” (NOAA42) as it flew through Hurricane Ian on 28 September, 2022, however, shows that even its experienced crew were shaken.

In the video, equipment is shown having fallen to the floor of the aircraft (“There goes the sondes!”), and after a camera-shaking bump, the crew can be heard reassuring each other, “We’re alright.”

Part of video of Hurricane Hunter flight into Hurricane Ian, September 28, 2022. Video courtesy of Nick Underwood.

“I’ve been flying hurricanes with NOAA for the last six years, and that was the worst flight that I’ve been on so far,” NOAA Programs and Integration Engineer Nick Underwood (who filmed the video) told MSNBC the next day. “We were coming through the western side of Hurricane Ian, it was intensifying up to its peak Category 4 strength, and we really got bounced around.”

As it turns out, the flight may have been the most turbulent ever on a Hurricane Hunter aircraft, at least in the past 20 years. In a study presented by Joshua Wadler of Embry-Riddle Aeronautical University at the 36th Conference on Hurricanes and Tropical Meteorology, researchers came up with new metrics to better quantify turbulence as experienced by an aircraft’s occupants—and ranked the top ten flights in Hurricane Hunter history.

“It was probably about ten minutes of really extreme turbulence,” said Wadler in his presentation during the “Innovative Observing Technologies to Advance Tropical Cyclone Operations and Research VI” session. As part of the flight crew, Wadler was on the team in charge of the Altius-600 small uncrewed aircraft system’s first-ever deployment into a hurricane.

Left and right: Josh Wadler and colleagues aboard the WP-3D Hurricane Hunter flight into Hurricane Ian, September 28, 2022. Photos courtesy of Jake Barlow. Center: Altius sUAS in front of WP-3D aircraft. Photo: Joe Cione.

“We were talking on the mission and we [thought], well, is this the bumpiest flight ever?” Wadler said. A few of the crew who had been flying such missions for decades seemed to think so. “We were like, okay, let’s try to figure it out.”

A bumpiness equation

Aside from corroborating hurricane researchers’ harrowing tales, understanding turbulence is becoming increasingly important given its predicted increase due to climate change, and with recent incidents including the death of a passenger during an exceptionally turbulent Singapore Airlines flight. Metrics for turbulence already exist, but most of those only represent vertical motion and focus on atmospheric properties rather than what happens to occupants. “We wanted … to have a 3-D turbulence metric, and one that describes the human experience,” said Wadler. 

When an aircraft rapidly accelerates  vertically or horizontally, everyone feels the dizzying rise or stomach-clenching drop. But if the aircraft rotates around its center of gravity in any direction, that acceleration will have different effects depending on where someone is seated–for example, when the aircraft tilts (or pitches) upward the people in the front of the aircraft will feel an upward acceleration while the people in the back will feel a downward acceleration. If the plane is also accelerating upwards, such as during takeoff, those in the front will experience a “double whammy” of acceleration. As Wadler noted, “Every seat on the plane experiences different rotational motions depending on where you are.”

Wadler and colleagues’ new “bumpiness” metric accounts for those differences. 

The research team combined flight-level data from all P-3 flights since 2004 (when high-enough-quality data became available). They calculated the acceleration forces acting on each seat in the plane relative to the plane’s center of gravity.

They defined the flight’s “bumpiness” by combining acceleration with jerk (the rate of change in acceleration over time), accounting for both in all three dimensions. This equation can be applied to any aircraft where the center of gravity and relative positions of the seats are known, and for which high-quality flight-level data are available. 

Bumpiness equation
Wadler and colleagues’ equation for defining “bumpiness” (B) in meters per second squared (m/s2).
Pilot's bed on floor

Their equation accounts equally for bumpiness in all directions, although it can be thrown off by sharp turns. Missions in which the plane turned sharply on purpose (for example, to calibrate instruments) were excluded from the team’s calculations.

Because the end result, the B or bumpiness value, values all dimensions of movement equally, it doesn’t always sync with what people expect. Some Twitter commenters belittled the video from the flight, possibly because it shows few large up-and-down bumps. The main types of motion experienced by the mission’s crew, however, were front-to-back and side-to-side.

<< The off-duty pilot’s bed was thrown from its bunk onto the floor during flight 20220928H1 into Hurricane Ian, due to lateral motion of the aircraft. Photo courtesy of Jake Barlow.

The bumpiest hurricane flights

The researchers calculated the top 10 bumpiest flights for each of the seats on the plane, based on the most turbulent part of each mission. 

WP-3D Orion seat map
Seat map of WP-3D Orion Hurricane Hunter aircraft. Image: Josh Wadler.

For the person in seat 1 (the “pilot flying,” in the front left seat on the plane), the Hurricane Ian flight was in fact the bumpiest by far—with a B value of 6.04 m/s2, 34% bumpier than any other flight for which good data were available. The second highest B value was experienced during Hurricane Irma in 2017 (B value: 4.5 m/s2), the third by a flight into Hurricane Sam in 2021 (B value: 4.39 m/s2). Subjective rankings from surveyed flight crews came up with a wide range of answers about their bumpiest flights, but were roughly in the same ballpark as those calculated by B value.

RankStorm NameMission IDMaximum Bumpiness Value (m/s2)
1IAN20220928H16.04
2IRMA20170908H24.50
3SAM20210929H24.39
4LANE(EP)20180822H14.28
5FELIX20070902H14.27
6DORIAN20190830H24.08
7PATRICIA(EP)20151023I14.05
8RAFAEL20121015H14.02
9GONZALO20141017I13.90
10DORIAN20190904H13.70
Rankings of B values for Hurricane Hunter flights since 2004, for the pilot in seat 1.

On the Hurricane Ian mission, the greatest B value (6.13 m/s2) was experienced by the second pilot, sitting in seat 2. Wadler was in seat 10. “I was very fearful during this mission,” he noted during his presentation. But, “lo and behold, my seat had the lowest [bumpiness] value by far.” The pilot in seat 1 experienced 37% worse turbulence than Wadler’s seat in the middle of the plane (6.04 m/s2 vs. 4.4 m/s2).

Seatmax Bumpiness (m/s2)
16.04
26.13
36.02
45.87
55.52
65.68
75.03
85.08
94.79
104.4
114.46
124.45
134.54
144.52
154.45
164.53
174.51
184.59
194.55
Rankings of B values for all seats on the Hurricane Hunter flight 20220928H1.

For seat 1, the Ian flight (Flight 20220928H1) ranked above all other flights for back-front and lateral motion. Yet in terms of up-down motion, a mission during Hurricane Lane ranked far higher, with a vertical B value of 17.1; Ian’s highest vertical B value was 8.43, ranking it seventh in terms of vertical motion. When all metrics are combined, however, the Ian flight came out on top. “It’s normal to have vertical bumps with eyewall updrafts and downdrafts,” Wadler noted in a later conversation, “but the lateral motions are rare. … The dropsondes went all over the cabin.”

Currently the bumpiness rankings only count the highest B value experienced during a flight. In future work, the research team aims to develop an equation that can account for cumulative bumpiness over time—a “queasiness index.” We’re well on the way to finding out what flights would make even the most iron-stomached hurricane hunter, in Wadler’s words, “very happy to be on the ground.”

Want to know more about what it’s like to fly a research mission into a hurricane? Take a virtual tour of a Hurricane Hunter aircraft “Miss Piggy.”

Header photo: View from NOAA WP-3D Hurricane Hunter aircraft “Kermit” during flight 20220928H1 into Hurricane Ian. Photo courtesy of Joshua Wadler.

About 36Hurricanes

The 36th Conference on Hurricanes and Tropical Meteorology brought together hundreds of hurricane researchers, modeling experts, forecasters, emergency managers, communicators, and more May 6-10, 2024, in Long Beach, California to discuss the latest in tropical cyclones and other tropical weather phenomena. It was hosted by the AMS Committee on Tropical Meteorology and Tropical Cyclones.

You can view the online program here. All conference presentations will become available to the public starting in August 2024.

AMS 2024 Session Highlight: WRN Asks “What If…?”

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Graphic: WRN Asks "What If...?"

Since 2013, the AMS Symposium on Building a Weather-Ready Nation (WRN) has brought together meteorologists and other Weather, Water, and Climate Enterprise partners to discuss efforts in advancing what it means to be “Weather-Ready.” At the 104th AMS Annual Meeting, for the second year in a row, the WRN Symposium will be opening their program Monday morning at 8:30 AM ET in Baltimore with a special, interactive session: “WRN Asks: What If…?” We spoke to one of the program chairs for this Symposium, Trevor Boucher from the National Weather Service, about why this session is unique and why AMS attendees might want to check it out.

What’s so special about this session, and how did it come about?

Trevor: The design and discussion are both very different from a traditional 12-minute presentation or panel session. Weather Ready Nation Symposium was created shortly after the National Weather Service introduced the WRN Initiative as a forum to share lessons learned, successes, and best practices. After a decade of this pursuit, several recurring themes arose: How do we, the Weather Enterprise, target underserved and vulnerable populations? How do we communicate our science effectively? How do we focus on our publics/partners while also maintaining our own well-being? These provocative questions are not easily addressed through the traditional paradigm of science conferences. Last year, the 11th WRN Symposium looked to an interactive, collaborative strategy to address big societal challenges, hosting a special session called, “WRN Asks: What if…?” which embraced the concept of “transformative learning.” We shifted the focus to collective, group discussion, and critically reflecting on what we’ve all learned since 2013.

This year’s “What if…?” session not only fits into the Annual Meeting’s “Living in a Changing Environment” theme but intentionally asks the provocative “elephant in the room” questions that are difficult to have in a traditional session. We designed this session as a “reverse panel,” where moderators provide a 3-minute “state of the science” with respect to their backgrounds and propose an open-ended, “What if…?” question to the audience. Then their role shifts to moderating audience discussion for the remainder of their 20-minute slot. So you might see notable names on the agenda, but they do the least amount of talking. The audience are the true panelists, sharing their opinions, their knowledge, and their concerns about these questions.

Where did this idea come from?

Trevor: To be honest, the design inspiration and name largely came from the Marvel Cinematic Universe (MCU). There is an animated series with the same name that explores how certain character storylines would progress in alternate scenarios or timelines. What would the implications be if certain details of these characters changed? Additionally, the show Black Mirror on Netflix is another inspiration, exploring how some seemingly inevitable technological advancements like AI or cybernetic implants may change our society. Similarly, we wanted to explore “What if…?” scenarios around how our science may look if things progress, change directions, or stay the same.

One of last year’s discussion moderators, Dr. Justin Sharpe, helped us also understand how this style of discussion fits very nicely into the concept of Transformative Learning (Mezirow, 1995, 2000) and engendering critical reflection of the audience. For the chairs, this also helps us reflect on how we craft our scientific discussions each year in our program. The single, double, and triple-loop deutero learning model (below) applies to both the audience and the chairs simultaneously.

Deutero Learning: Single, Double and Triple Loop Learning where single-loop learning is primarily related to considering one’s actions — such as improving efficiency; double-loop learning questions priority-setting, such as how solutions are determined (Argyris and Schön, 1978); and triple-loop learning questions underlying values and assumptions, asking, for example, what our goals may be (Sharpe, 2018, 2021, Sweiringa and Wierdsma, 1992).

The goal for this year’s session is to inspire the following year’s call for abstracts. We will be taking notes on everything discussed from the audience and planning follow-up sessions called “What’s Next?” based on the discussion. We hope people will be excited to contribute to these discussions for years to come.

How did the first “What if…” session go last year?

Trevor: Exceptionally well. Even though it was the first time we tried this and it was the opening Monday morning session of the Annual Meeting, with a LOT of competition for the membership to choose from, we had about 40-50 folks and had no problem with participation. In fact, we had to cut discussions off for all four questions proposed. I honestly think everyone who attended spoke up at some point through the 90-minute session.

My favorite part was an idea from Doug Hilderbrand, the creator of the WRN Symposium. He asked all the students in the audience to raise their hand, and promised they would be prioritized in the discussion, since these topics are likely what they will be grappling with throughout their upcoming careers.

What’s in store for attendees this year?

Trevor: Four new moderators with four new questions! And we have become a bit more emboldened to ask even more provocative questions this year. Some of them are excellent examples of #HowtoStartaMetFight (a popular Twitter hashtag from years ago). I personally can’t wait to see where the discussion takes us. The questions include…

“What if all weather information was probabilistic?”
Dr. Sean Ernst (OU’s Institute for Public Policy Research and Analysis)

“What if there wasn’t a stigma when talking about climate change?”
Jared Rennie (Research Meteorologist – NCEI)

“What if we didn’t change anything?”
Dr. Tanya Brown-Giammanco (Director – NIST Disaster and Failure Studies)

“What if there was no ego in the weather enterprise?”
Matt Lanza (Managing Editor – Space City Weather)

I’ve been on all our coordination calls and dry runs with these folks and we have had to cut short our 90-minute meetings each time because we just can’t help but discuss these important questions — and that’s just 6-7 of us. I really think AMS attendees will find it to be an invigorating way to begin their week in Baltimore.

Read more about the session.

About the AMS 104th Annual Meeting

The American Meteorological Society’s Annual Meeting brings together thousands of weather, water, and climate scientists, professionals, and students from across the United States and the world. Taking place 28 January to 1 February, 2024, the AMS 104th Annual Meeting will explore the latest scientific and professional advances in areas from renewable energy to space weather, weather and climate extremes, environmental health, and more. In addition, cross-cutting interdisciplinary sessions will explore the theme of Living in a Changing Environment, especially the role of the weather, water, and climate enterprise in helping improve society’s response to climate and environmental change. The Annual Meeting will be held at the Baltimore Convention Center, with online/hybrid participation options. Learn more at annual.ametsoc.org. 

Irrigation and Storms in the Inner Mongolian Desert

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Images from the DECODE project. Clockwise from top left: Microwave radiometer, wind LIDAR, researcher launching rawinsonde, eddy flux observation system, clouds forming at the boundary line, radar image of convective cells initiating along the boundary, photo of supercell storm growing from the boundary line. Photos courtesy of DECODE team.

A Research Spotlight from 32WAF/20Meso/28NWP

An irrigation oasis in Inner Mongolia, China, is providing unusual, real-world evidence about the effects of sharp vegetation contrasts on local and regional weather. Several presentations at the 32nd Conference on Weather Analysis and Forecasting, the 20th Conference on Mesoscale Processes, and the 28th Conference on Numerical Weather Prediction (32WAF/20Meso/28NWP) discussed findings from the 2022 DEsert-oasis COnvergence line and Deep convection Experiment (DECODE).

In Bayannur City, on the north side of a bend in the Yellow River, sits one of China’s largest irrigated areas: the 2,200-year-old, 769,333 hectare Hetao Irrigation District (HID), which was recognized as a World Heritage Irrigation Structure in 2019. All around this irrigation oasis is arid and semi-arid land, including the Kubuqi Desert to the south. We know that borders between land and water influence weather patterns, but there has been less real-world evidence gathered about the effects of differences in vegetation—and you can’t find a sharper divide than this one.

Image showing treeless mountains and sparsely vegetated foothills next to flat land. In the center of the photo is a dark green area of vegetation which contrasts sharply with the otherwise brown/tan landscape. A road runs to one edge of the green area. At the very right of the image, in the middle distance, is a large, wide building with a bright blue roof.
Above: Aerial view showing part of the Hetao Irrigation District and its sharp contrast with the surrounding desert areas. Video still courtesy of Yijing Liu. Below: Diagram of the juxtaposition between the boundary and its associated convective initiation (CI) and downstream propagation relative to surrounding terrain in Hetao Irrigation District. Image courtesy of Zhiyong Meng.

When cooler air from the Irrigation District meets warm wind from the desert, an atmospheric boundary line can sometimes be seen on radar. During the summer, convection often initiates at this boundary—sometimes leading to impressive storms that can travel long distances. DECODE researchers used a comprehensive set of observations—from radar and satellite to balloon sondes to flyovers—to examine this phenomenon. Their mission was to understand how the boundary forms and under what circumstances it might create unusual weather.

Different views of the boundary. Images courtesy of Zhiyong Meng.

On average, in the three months of summer each year from 2012 to 2016, 60 days produced a boundary, and 44 percent of those boundaries resulted in convective initiation (CI), noted Zhiyong Meng, of Peking University, in her July 20 presentation during Session 16 of 32WAF/20Meso/28NWP. The DECODE field experiment itself lasted 36 days in 2022, from 5 July to 9 August. With two field stations located on the oasis side, and four on the desert side, the teams were able to observe 23 boundaries and 11 occurrences of deep convection initiation, and even one case of a tornado.

Video still with green agricultural fiels and dark storm clouds in the background. A tornado funnel cloud is seen in the right side of the image. The DECODE project logo appears at the top left.
A tornado documented by the DECODE research team. It was generated by a thunderstorm formed at the boundary line. Video still courtesy of Yijing Liu.
Video still shows a bright bolt of lightning in the far left of the image. In the bottom right, a laser wind LIDAR device sits on a rooftop, pointing in the direction of the storm.
Lightning strike during the DECODE experiment. Video still courtesy of Yijing Liu.

Yipeng Huang, of Xiamen Key Laboratory of Straits Meteorology, outlined the most common conditions leading to a boundary/CI in a 21 July presentation. The researchers found that a boundary is most likely on warm summer days, when synoptic forcing is relatively weak, with dominant southerly winds opposing the oasis breeze, and a temperature over the desert that is apparently warmer than over the oasis. They found that along the boundary line between the two masses of air, convection initiation may occur when enough moist air advects north at the west edge of the subtropical high, moves out over the dry desert, and converges with a cool oasis breeze in an environment with large enough instability. Hongjun Liu of Peking University presented the mechanism for this process in a case study on 21 July.

Diagram of boundary formation and convection initiation near Hetao Irrigation District. Image courtesy of Zhiyong Meng.

Meng described “The most beautiful case, on July 29 [2022, when] the boundary produced a CI and the storm became very strong; it actually produced five-millimeter hail in the eastern part of the oasis.” They were also able to observe another storm as it split into two separate supercells. On July 25, a preexisting storm that passed over the area dissipated somewhat, likely due to sinking air over the oasis, then re-initiated strongly once it reached the boundary/convergence line over the desert. On occasion, the boundary would extend over the oasis and strongly increase the precipitation there.

Radar and photograph images of a large thunderstorm forming along the boundary line in the Kubuqi Desert on 29 July, 2022.

In the presentation immediately following Meng’s, Murong Zhang of Xiamen University noted that the team’s real-time forecasts were able to predict the formation of the boundary line in 21 out of 23 cases, although predicting convection initiation was more difficult. They were only able to predict 6 out of 11 CIs, as the numerical model tended to over-predict surface temperature, but under-predict moisture. The observations obtained from DECODE have been used to effectively improve the surface heat flux over the irrigated area, as shown in a presentation by Xuelei Wang of Peking University on the first day of the conference. You can see more from the DECODE team in this video created as part of the project:

With researchers from many institutions* participating, DECODE is an epic undertaking to study a unique natural phenomenon. As field research pioneer Prof. Edward Zipser of Utah University noted after Zhang’s talk, it’s “a program that we want to hear more about.”     

Group photo of the DECODE onsite team at one of the desert stations. Photo courtesy of Yijing Liu.

*DECODE participating organizations include Peking University, Inner Mongolia Meteorological Bureau, Nanjing University of Information Science and Technology, Xiamen Key Laboratory of Straits Meteorology, Xiamen University, Nanjing University, National Satellite Meteorological Center, Foshan Meteorological Bureau, and Jiangxi Storm Hunting Videos Culture Co., Ltd.

Featured image collage: Images from the DECODE project. Clockwise from top left: Microwave radiometer, wind LIDAR, researcher launching rawinsonde, eddy flux observation system, clouds forming at the boundary line, radar image of convective cells initiating along the boundary, photo of supercell storm growing from the boundary line. Photos courtesy of DECODE team.

About 32WAF/20Meso/28NWP

Predicting and understanding storms and other weather events is a complex business with real-world impacts. The American Meteorological Society’s 32nd Conference on Weather Analysis and Forecasting/28th Conference on Numerical Weather Prediction/20th Conference on Mesoscale Processes brought researchers, forecasters, emergency managers, and more together to learn about and discuss the latest scientific developments. The conferences took place in Madison, WI, and online 17–21 July, 2023. Recordings of the sessions are available here.

“Once in a Generation”: The 2022 Buffalo Blizzard

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Truck in snowdrift

A Research Spotlight from 32WAF/28NWP/20Meso

On 23 December, 2022, David Zaff of the National Weather Service’s Buffalo office walked out into a blank white world of howling wind. He headed to his car to get supplies, knowing there was no way to get home. He and his coworkers were trapped at the office, in the middle of one of the most deadly and disastrous blizzards Buffalo has ever seen.

Video by David Zaff, showing whiteout conditions outside NWS Buffalo office, December 23, 2022.

At the height of the 2022 holiday travel season, the four-day blizzard and lake-effect snow event knocked out power for more than 100,000 people, paralyzed emergency services and holiday travel, and left at least 47 dead. New York Governor Kathy Hochul described it as “the most devastating storm in Buffalo’s long, storied history.” Yet days earlier, Zaff and colleagues encountered skepticism from the public as they worked to warn the region.

Presenting at the J3 Joint Session at the 32nd Conference on Weather Analysis and Forecasting, the 20th Conference on Mesoscale Processes, and the 28th Conference on Numerical Weather Prediction, Zaff talked about the disaster and how the NWS countered accusations of hyperbole to get the word out.

Sounding the Alarm

The December 2022 snow was shocking, but not surprising. The pattern was easy enough to recognize, even 7–10 days earlier: a large high-pressure ridge forming over the western U.S., with a major trough in the east. “We knew something big was coming,” said Zaff. Five days before the storm, even low-resolution models suggested a major event. Four days ahead, the NWS started ringing the alarm bell. “We started saying, ‘A powerful storm will impact the region heading into the holiday weekend.’”

Three days out, the NWS issued an unusually emphatic Area Forecast Discussion (AFD):

“Some of the parameters of this intense storm are forecast to be climatologically ‘off the charts’ … One could certainly describe this storm system as a once in a generation type of event.”

NWS Lead Forecaster Robert Hamilton, Tuesday, December 20, 2022

That caused a stir, but many on social media dismissed it as hype. “People started saying, ‘There goes the weather service again,’” says Zaff.

He tried to find a way to show the science graphically, highlighting the forecast as “‘outside’ the climatology” for the time of year.

The graphic and its accompanying description got attention. By then, NWS Buffalo was communicating in earnest, including on social media. A tweet with a text-filled screengrab of the Winter Weather Message received 485,000 views. “A picture is worth a thousand words,” Zaff said, “except when people actually read the words, and see how impressive this event might be.”

Left: Graphic showing forecast surface pressure for Friday, December 23, 2022, with shading showing the relative frequency of the forecast MSLP values in the Buffalo region at that time of year. Source: David Zaff.

Surviving the Storm

Before noon on 23 December, visibility dropped to near zero, and it remained that way until around midnight on 25 December. 500 Millibar heights were “extraordinary” as the pressure trough moved into the Ohio Valley, and surface-level pressure was similarly unbelievable. A top wind speed of 79 mph was measured in downtown Buffalo at 10:10 a.m. on the 23rd, and winds in the 60–70 mph range lasted for 12 hours. “[It was] just an incredible bomb cyclone,” Zaff said. “An incredible storm.”

Image credit: David Zaff, NWS Meteorologist
Image credit: David Thomas, NWS Meteorologist
Image credit: Jon Hitchock, NWS Meteorologist
Photos by NWS Buffalo meteorologists during and after the 2022 blizzard. Left and right: NWS office exterior. Center: View of office door from the inside, with snow that made its way into the vestibule.

Zaff and some colleagues slept at the office; others attempted to drive in whiteout conditions using GPS alone, while some got stuck in drifts near the office and had to leave their cars to hike the rest of the way. Meanwhile, firefighters and airport employees worked to rescue motorists trapped nearby.

On December 24, the City of Buffalo issued “the scariest tweet I’ve ever seen,” said Zaff. The tweet stated that there were “no emergency services available” for Buffalo and numerous other towns.

“We knew by this time that there were fatalities occurring,” Zaff said. “And it just got worse and worse.”

Blizzard conditions lasted a full 37 hours–and lake effect snow wouldn’t stop for another two days. Three power substations shut down, frozen solid. Hundreds of power poles fell, and a significant percentage of locals were without power during the storm’s peak (some for days afterwards).

The 47 fatalities included people stranded outside, others who died from hypothermia in their homes, and some deaths due to delayed EMS response, according to Erie County. Hundreds of motorists were stranded on roadways during the storm. The Buffalo Niagara International Airport, with a proud legacy of operating under even the most horrific conditions, was closed for six days.

Zaff didn’t return home until late afternoon on the 25th, 18 hours after official blizzard conditions were over and having clocked 50+ hours at the office. On the drive, he saw iced-over buildings and trucks buried in snowdrifts. “It reminded me of [the movie] The Day After Tomorrow. … The impacts were tremendous.”

In his AMS presentation, Zaff compared the 2022 event to disastrous storms in 1977 (20+ fatalities, 69 mph winds, only 12” of snow yet drifts swallowed homes) and 1985 (5 fatalities, 53 mph winds, 33” snow), as well as the “Great Christmas Storm” of 1878, one of the first well-documented lake effect snow events, though lake-effect processes weren’t understood at the time. “This will likely be the storm of comparison now,” he says. “Once-in-a-generation” turned out to be right.

Future Lessons

Moving forward, said Zaff later, “Our intention is to further our relations with our Core Partners, including elected officials, emergency management, and the media [and] provide more probabilistic information that supports our ongoing Impact Decision Support Services. We hope to improve our outreach as well, instilling more confidence with the public.”

NWS will continue to provide improved decision support for partners, which may lead to more proactive road and school closures that could save lives in the future.

Photo at top: Buffalo roadways at 4 p.m. on December 25, 2022, 18 hours after blizzard conditions had passed. Photo credit: David Zaff.

About 32WAF/20Meso/28NWP

Predicting and understanding storms and other weather events is a complex business with real-world impacts. The American Meteorological Society’s 32nd Conference on Weather Analysis and Forecasting/28th Conference on Numerical Weather Prediction/20th Conference on Mesoscale Processes brought researchers, forecasters, emergency managers, and more together to learn about and discuss the latest scientific developments. The conferences took place in Madison, WI, and online 17–21 July, 2023. Recordings of the sessions are available here.