Extreme heat is the world's deadliest weather hazard, responsible for more deaths annually than floods, hurricanes, and tornadoes combined. As global temperatures rise, extreme heat events are becoming more frequent, more intense, and longer-lasting. Understanding how to protect yourself and others is a genuinely life-saving skill.

Understanding the Risk: It's Not Just Temperature

The danger from extreme heat is not simply about the thermometer reading. It is the combination of heat, humidity, duration, and individual vulnerability. A heat index above 41°C (when temperature and humidity are combined) represents dangerous territory for most healthy adults. Above 54°C heat index, heat stroke risk becomes extreme.

The most vulnerable groups include adults over 65, infants and young children, people with cardiovascular or respiratory conditions, those taking certain medications (diuretics, antihistamines, blood pressure medications), and people doing outdoor physical work.

Recognising Heat-Related Illness

Heat exhaustion is a warning stage: heavy sweating, cold or pale skin, fast or weak pulse, nausea, muscle cramps, tiredness, dizziness, and headache. The person is still sweating — their thermoregulation is working, but struggling.

Heat stroke is a medical emergency: body temperature above 39°C, hot dry skin (sweating may have stopped), rapid strong pulse, confusion, unconsciousness. Call emergency services immediately. Move the person to a cool location and apply cold water or ice to the neck, armpits, and groin while waiting for help.

Practical Heat Safety Measures

  • Hydration: Drink water consistently throughout the day — do not wait until you feel thirsty. In extreme heat, adults may need 3–4 litres per day. Avoid alcohol and excessive caffeine, both of which accelerate dehydration.
  • Timing: Schedule outdoor activities for early morning (before 10am) or evening (after 6pm). The peak heat and UV period is typically 11am–4pm.
  • Clothing: Lightweight, light-coloured, loose-fitting clothing reflects sunlight and allows air circulation. A wide-brimmed hat protects the head and neck.
  • Cool spaces: Access air-conditioned environments during peak heat hours — libraries, shopping centres, and community cooling centres are all viable options for those without home air conditioning.
  • Check on vulnerable people: During heatwaves, check on elderly neighbours, family members, and anyone with health conditions daily. Many heat stroke deaths occur because people are not found in time.
  • Never leave children or pets in vehicles: A car in direct sunlight can reach 60°C within 20 minutes, even on a moderately warm day.

Using Weather Forecasts to Prepare

Advance knowledge is one of the most powerful tools against heat-related illness. Monitor heat forecasts using the SunorSnow dashboard — the "Feels like" temperature incorporates heat index, and the UV Index reading helps you gauge the full environmental heat load. If you are travelling between cities, tracking all destinations simultaneously lets you anticipate conditions before you arrive and pack appropriately.