May in Grand Island averages a daily high of 22.8°C with nights around 9.9°C. Expect roughly 11.7 wet days totalling 120.6mm. Comfortable conditions for being outdoors all day.
Across the year, the best time to visit Grand Island is September–October.
Based on GRAND ISLAND CENTRAL NE REGIONAL AIRPORT, NE US (4.7km), 1995–2024. 30 years of May data.