Key Facts
• July 21: Summer skies dominate from Western Japan to Tohoku under Pacific high pressure.
• Afternoon: Inland and mountainous areas may see thunderstorms with heavy rain.
• Localized rainfall: Over 50 mm per hour possible, increasing small river water levels.
• Hokkaido: Cloudy skies expected; Okinawa: Intermittent rain with strong winds and high waves.
• Minimum temperatures: Around 25°C nationwide, leading to uncomfortable nights.
• Maximum temperatures: Many areas to reach 35°C, with heat alerts in 19 prefectures.
• Highest forecasted temperatures: 37°C in Maebashi, Kumagaya, Kofu, Kyoto, Toyooka, Kurume, and Hita.
• Weekly outlook: Persistent summer skies in Western to Northern Japan; thunderstorms likely inland.
• Okinawa: Cloudy and rainy days to continue; unsettled weather persists.
• Heatwave: Extreme heat expected in Kyushu to Kanto, with Obihiro in Hokkaido also reaching heatwave levels from July 22-24.
Summary
Japan will experience widespread summer skies on July 21, with thunderstorms expected inland and in mountainous areas during the afternoon. Localized heavy rain may exceed 50 mm per hour, posing risks of rapid river level increases. Hokkaido will see cloudy skies, while Okinawa faces intermittent rain, strong winds, and high waves. Minimum temperatures will hover around 25°C, leading to uncomfortable nights, while maximum temperatures are forecasted to reach 35°C or higher in many areas, with heat alerts issued for 19 prefectures. The weekly forecast indicates continued summer skies across Western to Northern Japan, with thunderstorms likely inland. Okinawa will remain cloudy and rainy. Extreme heat is expected in Kyushu to Kanto, with Hokkaido’s Obihiro also experiencing heatwave conditions from July 22-24. Residents are advised to stay hydrated and take precautions against heatstroke.
