In December, Hillsboro typically sees daytime highs of 7.4°C and overnight lows around 1.2°C. Compared to the annual average high of 16.4°C, December runs -9.0°C.
December in Hillsboro averages a daytime high of 7.4°C and an overnight low of 1.2°C.
December runs -9.0°C compared to Hillsboro's annual average high of 16.4°C, ranking #11 of 12 months by warmth.
Plan for daytime highs near 7.4°C and cooler evenings around 1.2°C.