Extreme heat can cause illness and death, but effective planning and actions can reduce its effects on health. Because effects of heat are associated with relative rather than absolute temperatures, even in New Zealand’s temperate climate people can experience negative health effects with modest increases in seasonal temperature. The purpose of these guidelines is to assist health and community service providers, health sector organisations, local government and other community organisations prepare heat health response plans.

The main sections of these guidelines are:

• objectives and scope – objectives and scope for these guidelines and how they fit into existing statutory frameworks
• heatwave hazard – the potential of heatwaves as a health hazard and the relevance of heatwave health planning in New Zealand
• health effects of heatwaves – heatwave-related health effects and vulnerable populations
• heat health actions – risk management actions.

These guidelines are a companion document to Heat Health Plans: Key Information (Te Whatu Ora 2023).