The Aftermath of China's Record-Breaking Sanfu Heat

The sanfu period in China, known for being the hottest time of the year according to the lunar calendar, has recently come to an end, yet significant heat remains pervasive. Characterized as the "dog days of summer," this year's sanfu spanned from July 20 to August 18 and ranked as the second hottest in history. During this period, the national average temperature reached 23.21 degrees Celsius, falling just short of the record set in 2024.

The intensity of this heat was remarkable and long-lasting, particularly in regions such as Xinjiang, Sichuan, and Henan, where many experienced more than two weeks of extreme conditions, with some areas exceeding 20 days of intense heat. Weather stations across the country reported record-breaking numbers for the longest consecutive days of high temperatures, attributed to a robust high-pressure system that created clear skies and warm air.

Even though the official sanfu has concluded, high temperatures are forecasted to persist. For the coming week, a strong high-pressure system is set to keep much of central and southern China sweltering, with cities like Hangzhou, Nanjing, and Shanghai bracing for additional days of severe heat, as Hangzhou is projected to reach temperatures as high as 40 degrees Celsius. This weather pattern is expected to remain throughout August, leaving southern China with ongoing hot and humid conditions, prompting authorities to recommend staying hydrated, wearing light clothing, and limiting outdoor activities during peak heat hours.