Key Facts
• September 1 (Monday) marks the start of the month with extreme heat in western and eastern Japan.
• Temperatures are expected to exceed 35°C in many areas, requiring heatstroke precautions.
• Northern Japan will experience rain due to approaching low pressure and fronts.
• Hokkaido faces the risk of localized heavy rain, especially in the afternoon and evening.
• Tohoku’s southern region will see sunshine, while the northern region will have increasing clouds and possible rain.
• Afternoon thunderstorms are possible in inland and mountainous areas of western and eastern Japan.
• Rain in Hokkaido may peak during the evening commute, with high humidity making it feel muggy.
Summary
September begins with intense heat across western and eastern Japan, with temperatures exceeding 35°C in many areas. Heatstroke precautions remain essential. In northern Japan, rain is expected due to low pressure and fronts, with Hokkaido at risk of localized heavy rain, particularly in the afternoon and evening. Tohoku’s southern region will enjoy sunshine, while the northern region will see increasing clouds and potential rain later in the day. Drivers in Hokkaido should exercise caution during the evening commute as rain intensifies. Despite the rain, temperatures will remain high, creating a humid and muggy atmosphere. Residents are advised to prepare for both heat and rain as September begins.
