If you’re looking forward to lots of outings with your partner, check out these details about year-round temperatures in Landquart: The hottest months are usually July and August with an average temp of 58°F, while the coldest months are January and February with an average of 30°F. The rainiest months in Landquart are August, June, July, and May, with each month seeing an average of 10 inches of rainfall.