In May, Arlington Heights typically sees daytime highs of 20.4°C and overnight lows around 8.8°C. Compared to the annual average high of 14.3°C, May runs +6.2°C.
May in Arlington Heights averages a daytime high of 20.4°C and an overnight low of 8.8°C.
May runs +6.2°C compared to Arlington Heights's annual average high of 14.3°C, ranking #5 of 12 months by warmth.
Plan for daytime highs near 20.4°C and cooler evenings around 8.8°C.