- Warning valid below 800 m a.s.l. - Possible impacts: Significant risk of circulatory problems and physical discomfort. - Recommendations for action: Drink at least 1.5 litres per day, preferably unsweetened and non-alcoholic drinks. Avoid physical exertion at the hottest time of day. Follow the recommendations of the Federal Office of Public Health FOPH. - Highest temperatures and humidity: 31 - 36 °C, 30 - 45 % - Lowest night temperatures: 18 - 22 °C - Peak phase of the event: Wed 12 - Fri 16 - Temporary mitigation: due to thunderstorms on, Fri 31.07.2026