13 Important Things to Do During a Heatwave

Heatwaves can wreak havoc on humans, animals, plants, and infrastructure. Heat stress can lead to health risks such as heatstroke, crops can fail, and equipment may malfunction or ignite. This guide outlines practical measures to prepare for and manage heatwaves effectively, incorporating the latest scientific insights into wet-bulb temperatures, which are crucial for understanding the risk of overheating.

New Tool: The Heatwatch App

Managing heatwave risks is now easier with the Heatwatch app, a free tool developed by the University of Sydney. This app provides hyper-local information on heat, humidity, and other environmental factors for specific postcode areas, making it an invaluable resource for Australian households, workers, and communities.

Unlike standard weather reports, Heatwatch accounts for combined heat and humidity, offering tailored insights to help you take preventive action against heat-related illnesses and risks. You can access the app and try it out here: Heatwatch.

Wet-Bulb Temperature

Recent research has refined our understanding of wet-bulb temperature, highlighting that dangerous conditions can occur at lower thresholds than previously thought. While it was once believed that a wet-bulb temperature of 43°C at 100% humidity posed a significant risk, updated findings suggest that temperatures as low as 32.5–35°C can be life-threatening (Sherwood & Huber, 2010).

Definition: Wet-bulb temperature is the lowest temperature air can achieve through evaporative cooling. When air reaches 100% humidity, wet-bulb and regular air temperatures align. In lower humidity, wet-bulb temperatures are lower than the air temperature.

This measurement is critical because our bodies rely on sweat evaporation to cool down. When the wet-bulb temperature rises above 35°C for an extended period, this cooling mechanism fails, leading to a significant risk of hyperthermia.

With climate change driving increased air moisture and rising ocean temperatures, Australians face a growing threat from heatwaves. A simple wet-bulb calculator can help assess risk levels: Wet-Bulb Calculator.

Prepare in Advance and Act Diligently

Preparation is key to managing heatwaves effectively. The following 13 strategies can help protect yourself, your family, animals, and plants during extreme heat.

1. Watch the Forecast

Regularly check weather forecasts and enable alerts for your area, particularly for extreme heat or fire risk. Monitoring conditions allows you to act preemptively.

2. Calculate the Wet-Bulb Temperature

Use wet-bulb temperature calculations daily during heatwaves to assess risk levels, particularly for outdoor workers, older adults, and children (Sherwood & Huber, 2010).

3. Keep in Touch

Maintain regular contact with neighbours, family, and friends. Vulnerable individuals, including the elderly and those with disabilities, may need additional support.

4. Create Shade

Use shade cloth to protect plants and animals from direct sunlight. Indoors, keep curtains or blinds closed to reduce heat transfer.

5. Set Up Cooling Areas

• Store ice near animal enclosures to create cooling zones.

• Provide cool baths or damp towels for humans and animals.

• Distribute chemical cold packs in your home for emergencies.

6. Ensure Access to Water

Keep gravity-fed water systems or large containers ready in case of power outages affecting electric pumps. Dehydration is a major risk; stock electrolyte solutions, juices, and water.

7. Eat Light, Frequent Meals

Heat can suppress appetite. Opt for small, nutritious meals rich in protein and healthy fats. Hydrating options, such as chilled soups or fruits, are ideal for humans and animals.

8. Establish Reliable Power Sources

Have a generator or solar power setup for essential equipment. Portable solar chargers are invaluable for keeping communication devices operational during outages.

9. Assess Risky Areas

Inspect your property for fire hazards, such as hay bales, which can spontaneously combust in extreme heat. Store flammable materials in isolated areas.

10. Prioritise Health

Avoid alcohol and non-essential medications during heatwaves as they can impair heat regulation. Ensure you take prescribed medications as directed and maintain healthy hydration and sleep patterns.

11. Prepare for Evacuation

Develop evacuation plans for people and animals. Pack emergency kits with food, water, medications, and contact lists. Establish a network for assistance, particularly for livestock.

12. Recognise Signs of Heat Illness

Symptoms of heatstroke include a high body temperature, red and dry skin, dizziness, and confusion. Immediate cooling and medical attention are vital if these signs appear (Australian Red Cross, 2021).

13. Take Care of Yourself

Ensure your clothing is light and breathable (e.g., cotton or linen) and stay hydrated even if you don’t feel thirsty. Use cold packs on pulse points (wrists, ankles, neck) to prevent overheating.

Conclusion

Heatwaves are a growing challenge, but with preparation and community support, their impacts can be mitigated. By following these 13 strategies and using resources like the Heatwatch app, you can protect yourself, your loved ones, and your environment during extreme heat events.

References

Australian Red Cross. (2021). Heatwaves and your health. Retrieved from https://www.redcross.org.au/

Sherwood, S. C., & Huber, M. (2010). An adaptability limit to climate change due to heat stress. Proceedings of the National Academy of Sciences, 107(21), 9552–9555. https://doi.org/10.1073/pnas.0913352107