District of Columbia, USA
Long term weather forecast
Long term weather forecast

December weather forecast and Climate
Washington, DC

December is a cold winter month with average lows dropping to 32°F (0°C). The weather is unpredictable with sunny days interspersed between intense cold days.
Daily average high is around a cold 46°F (7.8°C), but sometimes cold waves and winds resemble glacially chilly conditions.
Many art and theater establishments entertain enthusiastic souls inside their premises, and Washington, D.C. is home to more than a hundred historical sites and museums that may keep a tight budget visitor occupied in winter.
  • Average high temperature in December: 8.2°C

Warmest month (with highest average high temperature) is July (31.3°C).
Month with lowest average high temperature is January (6.3°C).

  • Average low temperature in December: 0.3°C

Month with highest average low temperature is July (21.7°C).
Coldest month (with lowest average low temperature) is January (-1.9°C).

  • Average humidity in December: 64.1%

Month with highest relative humidity is September (69.7%).
Month with lowest relative humidity is April (58%).

  • Average rainfall in December: 77.5mm

Wettest month (with highest rainfall) is May (101.3mm).
Driest month (with lowest rainfall) is February (66.5mm).

  • Average rainfall days in December: 9.7 days

Month with highest number of rainy days is May (11.1 days).
Month with lowest number of rainy days is October (7.7 days).

  • Average snowfall in December: 58.4mm

Month with highest snowfall is February (144.8mm).
Months with lowest snowfall are April, May, June, July, August, September and October (0mm).

  • Average snowfall days in December: 1.5 days

Month with highest number of snowfall days is January (3 days).
Months with lowest number of snowfall days are May, June, July, August, September and October (0 days).

  • Average daylight in December: 9h

Months with longest days are June and July (Average daylight: 15h).
Month with shortest days is December (Average daylight: 9h).

  • Average sunshine in December: 4.3h

Month with most sunshine is June (Average sunshine: 9.4h).
Month with least sunshine is December (Average sunshine: 4.3h).

  • Average UV index in December: 2

Months with highest UV index are June and July (UV index 9).
Months with lowest UV index are January and December (UV index 2).