The most pleasant months of the year for Willow Island are September, June and May. In Willow Island, there are 3 comfortable months with high temperatures in the range of 70-85°. July is the hottest month for Willow Island with an average high temperature of 87.5°, which ranks it as about average compared to other places in Nebraska. February is the snowiest month in Willow Island with 5.1 inches of snow, and 7 months of the year have significant snowfall. But there some days when the humidity becomes unpleasant, especially in July and August.