In December, Reston typically sees daytime highs of 7.5°C and overnight lows around -2.8°C. Compared to the annual average high of 18.8°C, December runs -11.3°C.
December in Reston averages a daytime high of 7.5°C and an overnight low of -2.8°C.
December runs -11.3°C compared to Reston's annual average high of 18.8°C, ranking #10 of 12 months by warmth.
Plan for daytime highs near 7.5°C and cooler evenings around -2.8°C.