Grayslake

What is the climate like in Grayslake?

The best time to visit Grayslake is typically June – September, with trip comfort peaking in September (7.0/10). Grayslake is warmest in July, when daily highs average 80°F (27°C), and coolest in January, when lows fall to about 21°F (-6°C). The wettest month is typically May and the driest is February; the year sees roughly 40 in (1024 mm) of precipitation.

• Best time to visitJune – September — comfort peaks in September (7.0/10)
• Warmest monthJuly — average high 80°F (27°C)
• Coolest monthJanuary — average low 21°F (-6°C)
• Wettest monthMay (4.9 in (123 mm))
• Driest monthFebruary (2.2 in (56 mm))
• Annual precipitation40 in (1024 mm)
• Based on2016-2025 daily ERA5 reanalysis data (10-year normals)
• Records fromMundelein 4wsw, 10 km away (1999-2024)