The most pleasant months of the year for Bartlett are September, May and June. In Bartlett, there are 4 comfortable months with high temperatures in the range of 70-85°. July is the hottest month for Bartlett with an average high temperature of 86.5°, which ranks it as one of the hottest places in Iowa. February is the snowiest month in Bartlett with 6.5 inches of snow, and 6 months of the year have significant snowfall. July is the most humid month, though humidity is low for most of the year.