In May, Sioux Falls typically sees daytime highs of 21.7°C and overnight lows around 7.7°C. Compared to the annual average high of 13.7°C, May runs +8.0°C.
May in Sioux Falls averages a daytime high of 21.7°C and an overnight low of 7.7°C.
May runs +8.0°C compared to Sioux Falls's annual average high of 13.7°C, ranking #5 of 12 months by warmth.
Plan for daytime highs near 21.7°C and cooler evenings around 7.7°C.