In December, Bethesda typically sees daytime highs of 7.8°C and overnight lows around -2.6°C. Compared to the annual average high of 19.0°C, December runs -11.2°C.
December in Bethesda averages a daytime high of 7.8°C and an overnight low of -2.6°C.
December runs -11.2°C compared to Bethesda's annual average high of 19.0°C, ranking #10 of 12 months by warmth.
Plan for daytime highs near 7.8°C and cooler evenings around -2.6°C.