United States · 1991–2020 normal
South Riding in
December.
Typical December weather in South Riding: 8.2°C by day, -1.8°C at night, 84 mm of rain over 8 wet days. These are measured 1991–2020 station normals, not a forecast.
Typical high8.2°C
Typical low-1.8°C
Rain84 mm
Wet days8
Comfort score 6 this month (September leads the year at 78). Daylight is calculated as 9 h 27 from latitude 38.92°.
Event window
Frost-level nights in December
The measured night-time normal is -1.8°C, so frost is typical rather than exceptional this month.
The evidence behind this page
One month,
from the same station.
- Place identity
- GeoNames 4786667
- NOAA station
- USW00093738 · WASHINGTON DULLES INTL AP
- Station distance
- 5.1 km from the place centre
- Coverage
- Strong coverage · 30 usable years
- Important limit
- Historical climate is not a forecast. Nearby stations can miss mountains, coasts, and local microclimates.