If you’re hoping to get lost in the rain on your romantic getaway, check out these details about year-round temperatures in Glencoe: The hottest months are usually July and August with an average temp of 51°F, while the coldest months are January and February with an average of 34°F. The rainiest months in Glencoe are December, October, January, and February, with each month seeing an average of 8 inches of rainfall.