Excessive Heat Warning

Introduction

Extreme heat is a formidable and often underestimated weather hazard. Statistics reveal that extreme heat is the leading cause of weather-related fatalities in the United States, claiming more lives on average each year than hurricanes, tornadoes, and floods combined. An excessive heat warning is a critical alert issued by the National Weather Service (NWS) for periods of dangerously hot and humid weather that pose a significant threat to human health and safety. Understanding these warnings, recognizing the associated risks, and knowing how to take protective action are paramount. This guide aims to equip everyone with the essential knowledge to navigate extreme heat events safely.

The significant number of fatalities attributed to heat, a hazard that may not always present with the dramatic visual impact of a hurricane or tornado, suggests that its potential dangers might not be fully appreciated by the public. This underscores a critical need for clear communication to bridge any perception gap regarding the lethal potential of extreme heat. Furthermore, a concerning trend shows a substantial increase in heat-related deaths in recent decades. For instance, provisional data indicates 1,714 heat-related deaths in the U.S. in 2022, a stark rise from previous years. This escalation likely reflects the broader impacts of environmental changes, including rising global temperatures and the increased frequency and intensity of heatwaves, emphasizing the urgent need for both immediate safety protocols and long-term adaptive strategies at individual, community, and systemic levels.

What is an Excessive Heat Warning?

An Excessive Heat Warning (EHW) is an alert issued by the National Weather Service when a period of dangerously hot weather, often accompanied by high humidity, is expected or occurring. These conditions are considered a significant threat to life, especially for vulnerable populations.

It is important to distinguish an Excessive Heat Warning from other NWS heat alerts:

Heat Advisory: This is issued when conditions are expected to cause significant discomfort or inconvenience and could lead to a threat to life if precautions are not taken. The criteria are generally less severe than for a warning. For example, in Pennsylvania, a heat advisory may be issued for a heat index of 100-104°F, while in New York, it might be 95-104°F, typically lasting for at least 2 hours in New York. Advisories are usually issued 1 to 3 days before the onset of dangerous heat.
Excessive Heat Watch: This is issued when conditions are favorable for an excessive heat event in the next 12 to 48 hours , or sometimes 24 to 72 hours or even 2 to 5 days in advance. An Excessive Heat Watch means the risk of a heat wave has increased, but its occurrence and timing are still uncertain. It serves as a "be prepared" signal, allowing individuals and communities to make preliminary plans.
Excessive Heat Warning: This is issued when an excessive heat event is expected, imminent, or has a very high probability of occurring, typically within 12 to 36 hours. This alert signifies that the heat conditions are extremely dangerous and pose a significant threat to life.

The National Weather Service uses several criteria to issue these warnings, which can include :

A combination of temperature and humidity that is considered dangerous for the human body, often measured by the Heat Index.
Heat that is above normal for that specific location compared to previous years.
Excessive heat conditions that are expected to last for at least two consecutive days.

Specific Heat Index thresholds for an Excessive Heat Warning typically involve a heat index of 105°F or higher, though in some regions it may be set at 110°F. These dangerous conditions often need to persist for at least two hours or, in some places, up to two days. Nighttime temperatures that remain above 75°F are also a concern, as they prevent both bodies and buildings from cooling down. Criteria for these warnings can vary by local climate and National Weather Service office procedures to best reflect regional risks. This flexibility ensures that alerts are tailored to the unique vulnerabilities of each area.

The tiered alert system—Watch, Advisory, Warning—provides a proactive approach to heat risk communication. A Watch encourages early awareness and planning, while an Advisory signals that conditions are becoming hazardous and precautions should be taken. A Warning, the highest level, demands immediate action to protect health and safety when extreme heat is imminent or ongoing. Understanding these alert levels is crucial for effective public response, especially since what qualifies as “dangerous” heat can differ greatly depending on local climate and how well the community is acclimatized or prepared.

Why Are Excessive Heat Warnings Issued?

Excessive Heat Warnings are issued with several critical objectives, all centered on safeguarding public well-being:

Protecting Public Health: This is the foremost purpose. These warnings are designed to prevent heat-related illnesses (such as heat exhaustion and heat stroke) and fatalities. Studies have shown that mortality rates begin to increase significantly when the heat index rises above certain thresholds, such as 104°F. Extreme heat is a leading weather-related cause of death, making these warnings vital.
Alerting Hospitals and Emergency Services: Warnings prompt healthcare facilities, emergency medical services, and other first responders to prepare for a potential surge in patients suffering from heat-related conditions. Public health departments often initiate enhanced surveillance during these periods, tracking emergency room visits and emergency calls to monitor the impact on the community.
Activating Community Resources: These warnings often trigger a series of community-level actions to provide relief and support:
- Opening Cooling Centers: Publicly accessible, air-conditioned facilities where people can escape the heat are often opened or have their hours extended.
- Distributing Water and Fans: Efforts may be made to distribute bottled water and electric fans, particularly to vulnerable individuals and communities.
- Implementing Checks on Vulnerable Individuals: Programs may be activated to check on the well-being of older adults, people with disabilities, those with chronic illnesses, and individuals who are home-bound or socially isolated.
- Triggering Regulatory Changes: In some jurisdictions, heat alerts can lead to temporary changes in regulations, such as moratoriums on utility shutoffs (electricity or water), halting evictions, or modifying outdoor work requirements to protect workers.
Raising Public Awareness: A crucial function of these warnings is to educate the public about the imminent dangers of extreme heat and the specific precautions that should be taken. Health professionals and public health agencies play a key role in disseminating this information through various channels.

The issuance of an Excessive Heat Warning triggers a coordinated response from various sectors, including government, health agencies, and community organizations, to protect public health. Its effectiveness relies on both timely alerts and the readiness of these groups to act together. Community resources like cooling centers and wellness checks are essential, especially for vulnerable populations such as low-income families, older adults, and those without access to air conditioning. These efforts not only address immediate risks but also highlight deeper social and health disparities. Ultimately, effective heat risk management involves both emergency measures and long-term strategies to reduce underlying vulnerabilities.

Who is Most at Risk?

While extreme heat can affect anyone, certain groups are more vulnerable to heat-related illnesses due to physiological factors, health status, environmental exposure, or socio-economic conditions. Understanding these vulnerabilities is key to targeted prevention and protection efforts.

Children (especially infants and young children): Their bodies are less able to regulate temperature effectively. They produce more heat per kilogram of body weight, have a higher surface-area-to-mass ratio which can lead to greater heat absorption from the environment, and have lower sweat production rates compared to adults. They also acclimatize more slowly to temperature changes and may not adequately replenish fluids if unsupervised. Young children often rely entirely on caregivers for protection from heat. They are frequently mentioned as a high-risk group.
Older Adults (typically aged 65 and over): The body's ability to regulate temperature can diminish with age. Older adults are more likely to have chronic health conditions (e.g., heart, lung, or kidney disease) and may take medications that can affect their body's response to heat, such as by impairing sweating or causing dehydration. Their sensation of thirst may also be reduced. Social isolation and living alone can further increase risk, as there may be no one to notice early signs of heat illness. Data has shown high rates of heat-related deaths in adults aged 55-64 as well.
Outdoor Workers: Individuals working in sectors like agriculture, construction, landscaping, and emergency response are often exposed to high temperatures and direct sunlight for extended periods, frequently while performing strenuous physical labor. They may also have limited access to essential workplace protections such as adequate rest, shade, and water, depending on their employment conditions.
Individuals with Chronic Health Conditions: People with cardiovascular diseases, respiratory illnesses (like asthma or COPD), diabetes, kidney disease, obesity, and mental health conditions are at heightened risk. Certain medications prescribed for these and other conditions (e.g., diuretics, antihistamines, beta-blockers, some psychiatric drugs) can interfere with the body's ability to regulate temperature or maintain hydration.
Low-Income Communities and People Experiencing Homelessness: These individuals often have limited or no access to air conditioning, adequate housing, or other cooling resources. People experiencing homelessness face direct and prolonged exposure to outdoor heat. Furthermore, urban heat island effects—where dense urban areas with extensive pavement and limited green space become significantly hotter than surrounding areas—are often more pronounced in low-income neighborhoods, which may also be areas historically affected by discriminatory practices like redlining.
Athletes and People Exercising Outdoors: Strenuous physical activity generates significant metabolic heat, increasing the body's heat load. Exercising in hot and humid conditions further strains the body's cooling mechanisms.
Pregnant Women: Physiological changes during pregnancy can make women more susceptible to heat stress.

Vulnerability to extreme heat goes beyond individual health and is shaped by socio-economic factors and urban environments, such as limited access to air conditioning and living in densely built areas with little green space. These risks are often intensified by systemic inequities rooted in urban planning and historical policies. Effective solutions require public health interventions that address these broader issues, like urban greening and access to affordable, cool housing. Additionally, vulnerability varies widely—outdoor workers, older adults, and children each face unique risks based on their circumstances. Therefore, strategies to reduce heat risk must be tailored to the specific needs of each vulnerable group.

What Happens During a Warning?

When an Excessive Heat Warning is issued, a range of actions are typically initiated by communities, authorities, and public health agencies to mitigate the risks. These actions are often guided by pre-established heat response plans.

Community Actions: Communities often implement several measures to help residents cope with extreme heat:

Opening Cooling Centers: Public buildings such as libraries, community centers, or dedicated facilities may be opened as cooling centers, providing air-conditioned spaces for people to find relief. Depending on the severity of the heat event (often guided by tools like the NWS HeatRisk forecast), these centers might extend their hours, sometimes even offering overnight shelter.
Distributing Water and Fans: Efforts may be undertaken to distribute bottled water and, where feasible, electric fans, particularly to at-risk populations and those without access to cooling.
Adjusting Outdoor Work Rules: Employers, especially those with outdoor workers, may be required or strongly encouraged to adjust work schedules to cooler parts of the day, provide more frequent rest breaks in shaded or cool areas, ensure access to water, and implement other protective measures. Regulatory bodies like OSHA also work on standards for heat injury and illness prevention in workplaces.
Outreach to At-Risk Individuals: Public health workers, social service agencies, or community volunteers may conduct wellness checks on older adults, individuals with disabilities, those living alone, or other known vulnerable persons to ensure they are safe and have access to cooling or assistance.
Modifying or Canceling Public Events: Organizers of outdoor events, especially those involving children (like day camps or sports), may be advised to reschedule, relocate to indoor venues, or cancel activities during peak heat periods.
Public Health Recommendations and Guidance: Public health departments disseminate heat safety messaging and provide specific guidance to partner agencies (like schools or homeless service providers) on appropriate response actions, aligning efforts on issues like operating cooling centers and reducing outdoor activities.

Public Alerts and Information Dissemination: Effective communication is vital during a heat emergency:

Increased Emergency Response Preparedness: Hospitals and emergency medical services are typically put on alert for an increase in heat-related illnesses and other emergencies exacerbated by heat.
Media Advisories and Public Notifications: The NWS, public health agencies, and local government officials issue alerts and safety information through various channels, including television, radio, websites, social media, and emergency alert systems. Some cities, like Philadelphia, have established collaborations with news organizations to provide educational information during heat alerts.
Use of Specialized Forecast Tools: Tools like the NWS HeatRisk forecast provide a color-numeric index indicating the level of risk for heat-related impacts over a 24-hour period, helping officials and the public understand the potential severity. Web portals like HEAT.gov serve as a centralized source of heat and health information for the nation.
Activation of Early Warning Systems (EWS): Comprehensive Heat Health Early Warning Systems (HHEWS) are designed to predict dangerous periods of extreme heat and disseminate timely, actionable alerts to relevant government agencies, civil society organizations, the media, and the general public. These systems can trigger critical public health responses aimed at saving lives.

The effectiveness of community actions during heat warnings relies on robust emergency plans, strong coordination, and clear communication. For example, King County, Washington, uses detailed protocols like the "Extreme Weather Annex" to guide their response, showing that well-prepared plans are far superior to ad-hoc efforts. There is also a shift toward sophisticated, health-based early warning systems—such as NWS HeatRisk and the CDC’s Heat and Health Index—which use both weather and health data to better predict risks. These targeted, data-driven approaches help allocate resources efficiently and protect vulnerable populations. Ongoing data collection remains crucial for refining these systems and reducing heat-related illness and death.

Symptoms and First Aid for Heat-Related Illnesses

Recognizing the signs of heat-related illnesses and knowing the correct first aid steps can be life-saving. Heat exhaustion and heat stroke are the most serious conditions.

Heat Exhaustion

Heat exhaustion occurs when the body loses excessive amounts of water and salt, usually through heavy sweating. It can develop suddenly or over time.

Symptoms of Heat Exhaustion:

Heavy sweating
Weakness or extreme fatigue
Cool, pale, clammy skin; possibly with goose bumps even in the heat
Fast, weak pulse
Muscle cramps
Dizziness or lightheadedness
Nausea or vomiting
Headache
Fainting (possible)
Extreme thirst
Mild confusion
Decreased urine output
Slightly elevated body temperature

First Aid for Heat Exhaustion:

Move the person to a cooler environment, preferably an air-conditioned room.
Loosen or remove any tight or unnecessary clothing.
Cool the person's body by applying cool, wet cloths or towels to the skin, or by having them sit in a cool bath or shower. Sponging with cool water and fanning can also help.
Offer sips of cool water or an electrolyte-containing sports drink if the person is conscious and not feeling nauseous.
Have the person lie down and elevate their legs and feet slightly.
Seek medical attention if: Symptoms worsen, last longer than one hour despite cooling measures, or if the person vomits. Call 911 if the person faints, becomes agitated or more confused, has a seizure, is unable to drink, or if their core body temperature (if measurable) reaches 104°F (40°C).

Heat Stroke (MEDICAL EMERGENCY)

Heat stroke is the most severe heat-related illness. It occurs when the body's temperature regulation system fails, and body temperature rises rapidly to dangerous levels. Heat stroke can cause permanent disability or death if not treated immediately.

Symptoms of Heat Stroke:

High body temperature: Typically above 103°F (39.4°C) or 104°F (40°C).
Altered mental state or behavior: Confusion, agitation, irritability, delirium, slurred speech, combativeness, or decreased responsiveness. This is a key sign.
Skin changes: Skin may be hot, red, and dry, OR it can be hot and moist/damp with sweat. The absence of sweating is not a required symptom.
Rapid and strong pulse.
Throbbing headache.
Dizziness or nausea.
Loss of coordination.
Seizures.
Unconsciousness or coma.

First Aid for Heat Stroke (CALL 911 IMMEDIATELY):

Call 911 or local emergency medical services immediately. This is a life-threatening emergency, and any delay in professional medical treatment can be fatal.
While waiting for emergency services to arrive, move the person to a cooler environment (e.g., shade, air-conditioned room).
Work to rapidly reduce the person's body temperature. Methods include:
- Immersing the person in a cool (not ice-cold) bath or shower.
- Sponging or spraying the person with cool water.
- Placing cool, wet cloths or ice packs on the head, neck, armpits, and groin, where major blood vessels are close to the skin surface.
- Covering the person with cool, damp sheets.
- Fanning the person vigorously while misting their skin with water.
Do NOT give the person anything to drink. Fluids should not be administered due to the risk of aspiration if their level of consciousness changes or if they have seizures. Paramedics will administer intravenous fluids if needed.
If the person loses consciousness and shows no signs of circulation (breathing, coughing, movement), begin CPR if trained to do so.

Key Differences: Heat Exhaustion vs. Heat Stroke

It is critical to understand that heat exhaustion can progress to heat stroke if not treated promptly. Therefore, early recognition of heat exhaustion symptoms and immediate intervention are crucial. Ignoring or trying to "tough out" these early signs significantly increases the risk of developing a life-threatening emergency. Public health messages must emphasize the importance of taking immediate cooling measures and seeking medical attention if symptoms of heat exhaustion do not improve.

A common misconception is that a person experiencing heat stroke will always have dry skin because they have stopped sweating. However, as noted, the skin can be hot and damp or moist , or the person may still be sweating heavily. Relying solely on the absence of sweat to rule out heat stroke can lead to dangerous delays in seeking emergency care. The presence of a high body temperature combined with significant changes in mental status are key indicators of heat stroke, regardless of whether the person is still sweating.

How to Stay Safe During an Excessive Heat Warning

During an excessive heat warning, taking proactive steps to protect oneself and others is essential. The following measures can significantly reduce the risk of heat-related illness:

Stay Hydrated: Drink plenty of fluids, primarily water, throughout the day. It is important not to wait until thirst develops, as thirst is an early sign of dehydration. When active in the heat, recommendations often suggest drinking about 1 cup (8 ounces) of water every 15-20 minutes. Avoid sugary drinks, caffeine, and alcohol, as these can contribute to dehydration.
Avoid Strenuous Activity: Reduce, reschedule, or eliminate strenuous outdoor activities, especially during the hottest part of the day (typically late morning to late afternoon). If physical activity is necessary, it should be scheduled for cooler times, such as early morning or late evening.
Wear Appropriate Clothing: Opt for lightweight, light-colored, and loose-fitting clothing made of breathable fabrics like cotton. Light colors reflect heat and sunlight, while loose fits allow for better air circulation.
Seek Air-Conditioned Environments: Spend as much time as possible in air-conditioned places. If a home is not air-conditioned, individuals can visit public cooling centers, libraries, shopping malls, or other air-conditioned public spaces. Even a few hours in air conditioning can help the body stay cooler.
Use Fans Wisely: Electric fans can provide comfort and help circulate air. However, it is crucial to note that when indoor temperatures are very high (e.g., above 90°F or 32°C), fans alone may not be effective in preventing heat-related illness. In such conditions, directing the flow of a fan toward oneself can sometimes increase dehydration by speeding up sweat evaporation without sufficiently cooling the body. In very hot, dry conditions, fans can act like convection ovens.
Check on Vulnerable Individuals: Regularly check on family members, friends, and neighbors who may be at higher risk, including older adults, infants and young children, people with chronic health conditions, and those who live alone.
Never Leave Anyone in a Parked Car: Temperatures inside a parked vehicle can rise to deadly levels within minutes, even with windows slightly open or when parked in the shade. Children, pets, and older adults are particularly vulnerable. It has been noted that a car's internal temperature can increase by 20°F in just 10 minutes.
Minimize Direct Sun Exposure: Stay out of direct sunlight as much as possible, especially during peak hours. Sunburn can reduce the body's ability to dissipate heat. If outdoor exposure is unavoidable, wear a wide-brimmed hat, sunglasses, and use a broad-spectrum sunscreen.
Eat Light Meals: Opt for smaller, lighter meals. Fruits and salads, which are easy to digest, are good choices. Avoid heavy, protein-rich meals that can increase metabolic heat production.
Take Cool Showers or Baths: Cool showers or baths can help lower body temperature.

Staying safe during extreme heat requires proactive planning, not just reacting when you feel hot. This means hydrating in advance, wearing suitable clothing, and scheduling activities to avoid the hottest parts of the day. Community support is also vital, as checking on vulnerable people—like the elderly or those living alone—can save lives. Many at-risk individuals may not recognize heat illness symptoms or be able to protect themselves. Simple acts of reaching out, combined with formal measures like cooling centers, make a significant difference.

Prevention Tips: Building Resilience to Heat

Beyond immediate safety measures during a heat warning, several long-term and daily strategies can help prevent heat-related illness and build resilience:

Maintain Consistent Hydration: Make adequate fluid intake a daily habit, not just a response to hot weather. Drinking water regularly throughout the day helps maintain proper hydration levels, which is crucial for the body's cooling mechanisms.
Avoid Peak Sun Hours for Outdoor Activities: Whenever possible, plan outdoor work, exercise, or recreation to avoid the most intense period of solar radiation and heat, typically between 10 a.m. and 4 p.m. (some sources suggest 11 a.m. to 3 p.m. or even as late as 6 p.m. for avoidance ).
Acclimatize Gradually to Hot Conditions: If moving to a hotter climate, or when starting a new outdoor job or exercise regimen in the heat, allow the body time to adjust. Gradual acclimatization typically takes about 10 to 14 days for healthy adults, but may take longer for children, older adults, or those with certain health conditions. It's also important to remember that acclimatization can be lost after about a week away from hotter climates.
Know Personal Risk Factors: Individuals should be aware of their personal risk factors, including age, chronic health conditions, and any medications they take that might increase susceptibility to heat. Consulting with a healthcare provider about how medications might affect heat tolerance is advisable.
Improve Home Cooling and Ventilation: For those living in heat-prone areas, ensuring the home has adequate ventilation is important. If air conditioning is not available, exploring options for improving natural ventilation, using fans effectively (while being mindful of temperature limits), and creating cooler spaces within the home can be beneficial. The design of homes, such as those with many south- and west-facing windows in temperate climates not traditionally reliant on AC, can intensify indoor heat.
Be Aware of the Local Environment: Recognize that urban areas can be significantly hotter than surrounding rural areas due to the "urban heat island" effect, where buildings and paved surfaces absorb and retain more heat. When outdoors, seeking out shaded areas and places with more greenery can help reduce heat exposure.

Effective prevention of heat illness relies on combining long-term habits like regular hydration and gradual acclimatization with situational awareness, such as avoiding peak sun and knowing personal risk factors. This multi-layered approach builds resilience to heat beyond just emergency actions. Acclimatization is especially crucial as climate change causes more frequent and intense heat waves, often catching populations unprepared at the start of the season. Public health systems should issue early warnings and employers must protect outdoor workers during these initial hot periods. Travelers to hotter regions also need to allow time for their bodies to adjust.

The Heat Index and Its Importance

Understanding the Heat Index is crucial for accurately assessing the risk posed by hot weather.

Definition: The Heat Index, often referred to as the "apparent temperature," is a measure that combines air temperature and relative humidity to determine how hot it actually feels to the human body.
Why it Matters More than Air Temperature Alone: The human body primarily cools itself through the evaporation of sweat. When relative humidity is high, the rate of evaporation from the skin decreases significantly. This means the body cannot cool itself as effectively, and the perceived temperature will feel much hotter than the actual air temperature. For example, if the air temperature is 90°F (32°C) and the relative humidity is 70%, the Heat Index can make it feel like 105°F (41°C). This "feels like" temperature is a better indicator of the potential stress on the body and the risk of heat-related illness.
Use by the National Weather Service: The NWS utilizes Heat Index values as a primary factor in deciding when and where to issue heat advisories, watches, and warnings.
The Sunshine Factor: It is critical to remember that Heat Index values are typically calculated for shady, light wind conditions. Exposure to direct, full sunshine can increase the apparent temperature by up to 15°F (about 8°C). This means the actual heat stress experienced by an individual in direct sunlight can be substantially higher than the reported Heat Index value.

The Heat Index shows that heat risk depends on more than just temperature—it’s also affected by humidity, which can make moderate heat feel much more dangerous. Humid heat often feels worse and poses greater health risks than dry heat at the same temperature, so understanding the Heat Index is crucial for personal safety. In addition, the “sunshine factor” highlights how seeking shade can significantly lower your heat exposure. This underscores the value of personal choices and the need for urban planning that includes shade, like trees and covered areas. Together, these factors help people and communities stay safer during heat waves.

Heat Safety Checklist

To enhance understanding and recall of key safety measures, a visual checklist can be a very effective tool. A "Heat Safety Checklist" graphic could summarize the most important actions from the "How to Stay Safe" and "Prevention Tips" sections. This could include simple icons and brief text for actions such as:

Drink plenty of water.
Wear light, loose clothing.
Stay in air-conditioned spaces.
Check on neighbors and family.
Avoid outdoor activity during peak heat.
Never leave people or pets in cars.
Know signs of heat illness.

Such a graphic would be easily digestible, shareable (especially on social media), and serve as a quick reminder of essential precautions. Visual aids often improve the accessibility and memorability of complex health information, catering to diverse learning styles and helping to ensure that critical messages are retained and acted upon.

Conclusion

Excessive heat warnings are vital alerts designed to protect public health from the dangers of extreme temperatures. Understanding these warnings, recognizing who is most at risk, and knowing the symptoms of heat-related illnesses are crucial for safety. Early identification of warning signs, such as heavy sweating or confusion, and prompt first aid can prevent serious consequences. Staying hydrated, wearing suitable clothing, and seeking cool environments are key preventive measures. By taking these warnings seriously and looking out for vulnerable individuals, communities can reduce risks and build resilience against rising temperatures.

Frequently Asked Questions

Q: What is the difference between heat exhaustion and heat stroke?
A: Heat exhaustion causes heavy sweating, weakness, and cool, clammy skin. Heat stroke is life-threatening, with confusion, hot skin, rapid pulse, and possible unconsciousness—call 911 immediately if suspected.

Q: How much water should be consumed during an excessive heat warning?
A: Aim for at least 8 cups (64 ounces) of water daily, increasing if active or outdoors. Drink small amounts frequently and avoid exceeding 48 ounces (1.5 quarts) per hour to prevent overhydration.

Q: Is it safe to exercise during a heat warning?
A: Avoid strenuous outdoor activity during peak heat; exercise early, late, or indoors. Hydrate well, start slowly, and take frequent breaks in cool or shaded areas.

Q: What should be done if someone shows signs of heat-related illness?
A: Move them to a cool place, loosen clothing, and cool their body with wet cloths or a bath. Offer water if conscious; seek medical help if symptoms persist or worsen, and call 911 for heat stroke.

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