Isumi

What is the climate like in Isumi?

The best time to visit Isumi is typically October, the year's most comfortable month (6.2/10). Isumi is warmest in August, when daily highs average 84°F (29°C), and coolest in January, when lows fall to about 44°F (7°C). The wettest month is typically October and the driest is January; the year sees roughly 72 in (1819 mm) of precipitation.

• Best time to visitOctober — the year's comfort peak (6.2/10)
• Warmest monthAugust — average high 84°F (29°C)
• Coolest monthJanuary — average low 44°F (7°C)
• Wettest monthOctober (8.9 in (226 mm))
• Driest monthJanuary (3.4 in (87 mm))
• Annual precipitation72 in (1819 mm)
• Based on2016-2025 daily ERA5 reanalysis data (10-year normals)
• Records fromKatsuura, 12 km away (1951-2026)