Sioux City

What is the climate like in Sioux City?

The best time to visit Sioux City is typically June – October, with trip comfort peaking in September (7.5/10). Sioux City is warmest in July, when daily highs average 86°F (30°C), and coolest in January, when lows fall to about 16°F (-9°C). The wettest month is typically May and the driest is February; the year sees roughly 33 in (833 mm) of precipitation.

• Best time to visitJune – October — comfort peaks in September (7.5/10)
• Warmest monthJuly — average high 86°F (30°C)
• Coolest monthJanuary — average low 16°F (-9°C)
• Wettest monthMay (5.1 in (129 mm))
• Driest monthFebruary (1.1 in (27 mm))
• Annual precipitation33 in (833 mm)
• Based on2016-2025 daily ERA5 reanalysis data (10-year normals)
• Records fromSioux City AP, 12 km away (1940-2026)