Strengthening heat early warning systems policy brief

This policy brief presents recommendations on extreme heat early warning. Heat is an escalating global threat, contributing to nearly half a million deaths annually and impacting multiple sectors including health, agriculture, infrastructure, and livelihoods. Despite these risks, many countries lack sufficient preparedness and Heat Early Warning Systems (HEWS). The effectiveness of HEWS varies widely, with less than 54% of national meteorological services issuing heat warnings. Fragmentation in roles, limited community engagement, and variable approaches to risk communication and action planning persist as notable gaps. Embedding heat risks within multi-hazard early warning and disaster risk management frameworks, combined with inclusive governance, are critical for improving societal resilience.

The policy brief presents seven cross-cutting recommendations:

• Establish clear governance for HEWS by defining roles, ensuring coordination across sectors and levels of government, securing sustained financing, and embedding heat action plans in relevant DRR and adaptation frameworks.
• Strengthen comprehensive, locally relevant heat risk knowledge by integrating scientific data and community perspectives to identify and regularly update who/what is at risk, and understand exposure, vulnerabilities, and impacts across all sectors.
• Address prolonged and seasonal heat risks by moving beyond event-based warnings and providing continuous monitoring, risk communication, and tailored actions throughout heat seasons.
• Improve local relevance of warnings through context-specific heat indices and thresholds informed by local climate, vulnerabilities, and health impacts.
• Strengthen heat risk communication and "first-mile" dissemination by using trusted channels, clear and actionable messaging, and behavioral insights to reach all at-risk populations, especially those with limited access to traditional media or digital technologies.
• Develop and strengthen Heat(-Health) Action Plans (HAPs/HHAPs) to ensure forecasts and warnings trigger timely, coordinated protective measures, specifying actions for diverse actors and populations.
• Regularly evaluate and adapt HEWS in light of changing climate, demographics, and vulnerabilities, using feedback, impact data, and learning processes to improve system performance and relevance.