Forecasting Heat Waves: Can We Predict Deaths Ahead?

Heatwaves can be deadly, as seen in Europe's 2018 and 2022 summers. But did you know that some of these extreme temperatures could be foreseen weeks in advance? Subseasonal forecasts, which predict weather 2 weeks to 2 months ahead, offer a glimpse into the future. Yet, we haven't fully explored how useful these forecasts could be for warning systems. In Switzerland, scientists combined climate epidemiology and subseasonal forecasts to look back at the 2018 and 2022 heat-related deaths in Zurich and Geneva. They used temperature and mortality data from 1990 to 2017 to understand the link between heat and deaths. Then, they used these patterns to predict deaths in 2018 and 2022 using 2-km resolution forecasts. The predictions were pretty accurate, especially for short heat waves. Longer heat waves were also anticipated, but less precisely. This shows that subseasonal forecasts could be a game-changer for warning systems during hot summers.