The WxEM Project
Wave 3: Compound Hazards
Motivation
- NWS forecasters communicate with core partners throughout the forecast and warning process to ensure that the information they provide is relevant, understandable, and actionable. Emergency Managers are among the most important partners. They are a core linkage between NWS information and community actions that save lives and protect property.
- Effective communication with EMs requires accurate and timely information about hazards (forecasts and warnings) and knowledge about types of information that EMs require when making decisions.
- The WxEM project will provide this information by identifying and talking with a diverse group of EMs who are willing provide routine feedback on new technologies, forecast products, and NWS decision support services.
- Surveys
- Experiments
- Interviews
Wave 3: Compound Hazards
- Objective: Understand Emergency Manager perception of events that occur in the same place at the same time, or compound hazards
- General compound hazards
- Tornado and Flash Flood events (TORFF)
- Compound hazards associated with tropical events
- Compound hazards as a result of Hurricane Ida
- EMs were also asked about vulnerability within their jurisdiction
- The impact of COVID on Emergency Management
- These slides provide basic information about the sample and highlight results from the Wave 3 survey
Survey Results
Geographic distribution of respondents
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Survey Results
In general, how would you rate the risk of the following hazardous weather events to the people in your jurisdiction(s)?
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Survey Results
Do you think most people in your jurisdiction(s) know what they can do to protect themselves from wind or water related hazards?
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Survey Results
Are there publicly accessible shelters where people can go to prior to wind or water related hazards in your jurisdiction(s)?
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Survey Results
What is the most effective way for members of the public to contact you leading up to…
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Survey Results
Some EMs indicated that members of the public would use different methods to contact them. These included:
- Websites or mobile apps
- “a SaaS communication platform (mobile+Web) that citizens can be alerted and text message with location to share their situation, offer help or money”
- Amateur radio
Survey Results
What is the most effective way for you to contact members of the public leading up to…
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Survey Results
Some EMs indicated that they use different methods to communicate with the public. These included:
- Mass notification systems (a majority of responses)
- These include systems such as Reverse 911, Everbridge, Code Red, Nexel, etc.
- A combination of the given choices
Survey Results
Can you think of any compound hazards that occur (or might occur) in your jurisdiction(s)? If so, please explain here.
- Winter hazards
- “Bitter cold and snow/blizzards”
- Severe weather hazards
- “Severe storms that cause both tornado and flooding”
- Tropical hazards
- “Hurricane events would lead to high wind risks, flash flooding, and coastal flooding risks.”
- Fire hazards
- “fire burn scar debris flows and flooding”
- Societal hazards
- “power outages and extreme heat/cold”
Compound Tornado and Flash Flood (TORFF) Events
Next, we would like to ask you about compound hazards that take a specific form. Co-occurring tornado and flash flood (TORFF) events are fairly common across the U.S., occurring about 400 times per year on average. During these events, the National Weather Service (NWS) issues tornado and flash flood warnings at the same time in the same place.
Survey Results
For example, in the graphic below, Town B is experiencing both a tornado warning and flash flood warning.
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Survey Results
Has your jurisdiction(s) experienced a compound tornado-flash flood (TORFF) event?
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Survey Results
Do you think your jurisdiction(s) could experience a compound tornado-flash flood (TORFF) event in the future?
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Survey Results
How would you rate the risk of compound tornado-flash flood (TORFF) events to the people in your jurisdiction(s)?
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Survey Results
Do you have a specific communication plan in place to deal with compound tornado-flash flood (TORFF) events in your jurisdiction(s)?
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Survey Results
Can you briefly explain how your communication plan for compound tornado-flash flood (TORFF) events differs from plans that focus on tornadoes or flash flooding alone?
- Notifying people of both hazards:
- “Our communications plan explains both hazards and lets people know that both hazards are occurring at the same time.”
- Giving safety information about the most relevant or hazardous threat:
- “For safety messaging - public would be reminded of safety messaging for both threats prior to the storm. During storm - warnings would be explained and residents would be encouraged to choose the actions that protect them from the most dangerous hazard at the time.”
- Focus on one threat:
- “We will message the most threatening significant event, like a tornado, as well as message the potential for flash flooding. We have a relatively large county, so our focus would be on the tornado area on messaging first and foremost.”
- Message information that would protect from both threats:
- “Sheltering may be different. Here, basements are common, but if flash flooding has flooded the basements, I may suggest a secondary shelter for the tornado like an interior closet or bathroom.”
Survey Results
Forecast communication can be difficult leading up to compound tornado-flash flood (TORFF) events. One challenge is which hazard to prioritize. When both tornadoes and flash floods are possible, it can be difficult to provide sufficient information about both hazards as they evolve. Sometimes this means that emergency managers are not sure what hazards to focus on as possible TORFF hazards approach.
Survey Results
In your experience, do local television stations and NWS offices provide sufficient information about both hazards leading up to compound tornado-flash flood (TORFF) events?
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Survey Results
Can you think of any ways to improve the forecast communication process leading up to compound tornado-flash flood (TORFF) events?
- Covering both threats
- “Continue to give information on both. Tornado and Flood. With the size of our county, even if you don’t experience one you will likely experience the other.”
- Educating the public
- “I have not heard the term TORFF used in news media or NWS warnings. People love new acronyms, so perhaps educating about what a TORFF is could grab attention of the public?”
- “People still discount flash flood warnings. We have to do better relaying the risk. Extreme winds are not taken as seriously as a tornado warning. We need better public education in this area.”
- One message
- “It appears theses warnings are often two warnings stapled together a more cohesive message may be beneficial”
- Message protective action for both threats
- “Try to identify action directives that could apply to both hazards”
- Message the potential for compound hazards before the event
- “Ensure effective use of social media prior to expected events, to inform the public about what might happen, how likely it is to happen, and what can be done to stay safe.”
Survey Results
In the graphic below, the storm phase is indicated in red and the remnant phase is in blue.
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Survey Results
Has your jurisdiction(s) experienced a tropical storm/hurricane during the storm or remnant phase?
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Survey Results
Do you think it is possible that your jurisdiction(s) will experience a tropical storm/hurricane during the storm or remnant phase in the future?
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Survey Results
About how often does your jurisdiction(s) experience a tropical storm/hurricane during the storm phase?
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Survey Results
Compound wind and water hazards are relatively common during the storm and remnant phases of tropical storms/hurricanes. During these events, the National Weather Service (NWS) issues warnings for wind-related hazards (such as tropical storm warnings, hurricane warnings, high wind warnings, and tornado warnings) and water-related hazards (such as storm surge warnings, flood warnings, and flash flood warnings) at the same time in the same place.
Survey Results
Has your jurisdiction(s) experienced a compound wind and water event during the storm or remnant phase of a tropical storm/hurricane?
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Survey Results
How would you rate the risk of compound wind and water events during the storm or remnant phase of tropical storms/hurricanes to the people in your jurisdiction(s)?
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Survey Results
Do you have a specific communication plan in place to deal with compound wind and water events during the storm or remnant phase of tropical storms/hurricanes in your jurisdiction(s)?
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Survey Results
Can you briefly explain how your communication plan for wind and water events differs from plans that focus on wind or water threats alone?
- “Greater detail on impact area and local resources availability.”
- “We speak to the different hazards associated with the event. Try to use emergency alerts to bring overall attention to the incident and then other message to speak to the hazards in greater depth.”
Survey Results
Forecast communication can be difficult leading up to and during compound wind and water events that stem from the storm or remnant phase of tropical storms/hurricanes. One challenge is which hazard to prioritize. When both wind and water hazards are possible, it can be difficult to provide sufficient information about both. Sometimes this means that emergency managers are not sure what hazards to focus on as possible wind and water hazards approach.
Survey Results
In your experience, do local television stations and NWS offices provide sufficient information about both hazards leading up to compound wind and water events?
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Survey Results
Can you think of any ways to improve the forecast communication process leading up to compound wind and water events that stem from the storm or remnant phase of tropical storms/hurricanes?
- Emphasize impacts
- “Less focus on the category of a storm and more visualization of potential impacts.”
- Focus on biggest threat
- “The only thing I would say is to add the emphasis to the bigger threat - for example, with Katrina it was wind, with Florence it was riverine rise, with Ian it was surge. While all three are a threat - the one that will most likely have the biggest impact and damages to the area should be highlighted a little more.”
- Avoid conflicting information
- “Need a solution to telling folks in homes with rising water to get on the roof when high winds and tornadoes are also an ongoing threats.”
Compound Hazards as a result of Hurricane Ida
In this section of the survey, we have a few specific questions for emergency managers who currently work in areas that were impacted by the storm or remnant phase of Hurricane Ida. As you may recall, Ida was a Category 4 hurricane that made landfall in Louisiana on August 26, 2021. After landfall, it followed a path to the Northeast, affecting 22 states until the remnant phase dissipated on September 5, 2021.
Compound Hazards as a result of Hurricane Ida
The map below shows the areas that were affected by Hurricane Ida.
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Survey Results
Based on this map, was your jurisdiction(s) impacted by Hurricane Ida’s storm or remnant phases?
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Survey Results
In the 24 to 36 hours before Hurricane Ida impacted your jurisdiction(s), what weather hazard were you most concerned about?
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Did the weather hazard you were most concerned about change as the storm or remnants began to impact your jurisdiction(s)?
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Survey Results
What weather hazard became most concerning as Hurricane Ida began to impact your jurisdiction(s)?
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Survey Results
Did compound hazards from Hurricane Ida’s storm or remnant phase impact your jurisdiction(s)? If so, what hazards co-occurred?
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Survey Results
Is there anything specific you want to tell us about your experience with compound hazards leading up to Hurricane Ida?
- “It is difficult to predict the exact impacts of the event due to the interrelated effect of the wind and rain.”
- “We handle them the same as a single hazard event, just more data presented to the public. No need to over complicate the issues presented.”
- “For us- we had small flooding with tornado warnings but we were able to focus on one or the other in the EOC.”
General Compound Hazards
Forecast communication can be difficult leading up to and during weather events that produce compound hazards. One challenge is what hazard to prioritize. When multiple hazards are possible, it can be difficult to provide sufficient information about all of them. Sometimes this means that emergency managers are not sure what hazards to focus on as hazards approach their jurisdiction.
Survey Results
In your experience, do local television stations and NWS Offices provide sufficient information about all hazards leading up to and during weather events that produce compound hazards?
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Survey Results
Can you think of any ways to improve the forecast communication process leading up to weather events that produce compound hazards?
- Focus on both hazards:
- “Continuing to push out the messaging that multiple hazards are possible and that people should have multiple different ways to respond to said compound hazards if they were to occur.”
- “When compound hazards are forecasted, emphasize the multiple hazards. Too often one hazard is emphasized, with little discussion of additional hazards.”
Vulnerability
The impact of compound hazards can vary from community to community, often because one is more physically, socially, and/or economically vulnerable than the other.
Vulnerability
In some jurisdictions, the following populations are especially vulnerable to compound hazards. When you think about your jurisdiction(s), which of these groups do you worry most about?
- Other populations mentioned include:
- Unhoused populations
- Students
- Communities that are inaccessible or difficult to reach
Survey Results
Can you briefly explain what concerns you most about this group?
- Low-income households
- “These households are less resilient. They often do not have the ability to withstand a weather event that would be much less impactful for a higher income family. They often do not have transportation or other family resources to move away from an approaching hazard like a flood.”
- Elderly
- “They have fixed resource access, tend to be too proud to ask for help, and are often most at risk for the secondary threats such as heat exhaustion, loss of power, etc..”
Survey Results
Can you briefly explain what concerns you most about this group? (cont.)
- Racial/ethnic minorities
- “Often don’t trust government for info”
- Immigrant communities
- “We don’t do a good job at communicating hazards and risks to immigrants and migrants in their native languages”
- Individuals with disabilities
- “Getting them to safety, communication, transportation, and care”
COVID-19 and Emergency Management
We are primarily interested in the weather, but compound hazards often involve more than weather hazards. In the last few years, for example, many emergency managers have been dealing with compound weather and public health (COVID-19) hazards. Some emergency managers have told us that this has made it more difficult to deal with weather hazards alone.
Survey Results
Has COVID-19 impacted the capacity of people in your jurisdiction(s) or emergency managers to prepare for and respond to hazardous weather events?
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Panel Demographics
As you know, the EM population is very diverse. EMs have many different backgrounds, experiences, and perspectives. Understanding this diversity will help forecasters think about the variety of EMs they communicate with. If you have a moment, can you tell us a little more about yourself?
Survey Results
How old are you?
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How would you describe your gender?
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What is your race or ethnicity?
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What is the highest level of school you have completed?
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How would you describe your jurisdiction(s)? If you serve multiple jurisdictions or a large jurisdiction with multiple communities, pick the one that predominates in your mind.
