In May, Hillsboro typically sees daytime highs of 19.4°C and overnight lows around 6.6°C. Compared to the annual average high of 16.4°C, May runs +3.0°C.
May in Hillsboro averages a daytime high of 19.4°C and an overnight low of 6.6°C.
May runs +3.0°C compared to Hillsboro's annual average high of 16.4°C, ranking #5 of 12 months by warmth.
Plan for daytime highs near 19.4°C and cooler evenings around 6.6°C.