Sumner

What is the climate like in Sumner?

The best time to visit Sumner is typically July – August, with trip comfort peaking in July (8.6/10). Sumner is warmest in August, when daily highs average 76°F (25°C), and coolest in February, when lows fall to about 37°F (3°C). The wettest month is typically December and the driest is July; the year sees roughly 56 in (1434 mm) of precipitation.

• Best time to visitJuly – August — comfort peaks in July (8.6/10)
• Warmest monthAugust — average high 76°F (25°C)
• Coolest monthFebruary — average low 37°F (3°C)
• Wettest monthDecember (8.8 in (223 mm))
• Driest monthJuly (0.6 in (15 mm))
• Annual precipitation56 in (1434 mm)
• Based on2016-2025 daily ERA5 reanalysis data (10-year normals)
• Records fromMcmillin Rsvr, 8 km away (1941-2026)