A closer look at December’s wild weather

 

A view of National Harbor

This December will finish as DC’s coldest since 2010. Although it will also finish as a drier than average month, Washingtonians still experienced the highest December snowfall total in eight years.

The first 17 days of December were colder than average in the nation’s capital. The coldest day was December 15 with daily high/low temperatures of 29°/18°. While nine days since December 18 were warmer than average, this month will still finish more than four degrees colder than average. With a monthly average temperature of 37.5° as of December 30, this month will be DC’s coldest since 2010 (34.6°).

December will also finish as a drier than average month with only 1.77”, well below the monthly average of 3.41”. This month’s wettest day was December 2 with 0.86” of rain and a high temperature of only 42° (11° below average). Only 1.5” of snow fell this month. While below DC’s December average of 1.7”, it was still the highest monthly total since 2017 (1.9”). 

New Year’s Eve will feature colder than average temperatures in the nation’s capital. That will end DC’s recent trend for warmer than average weather on December 31 that lasted from 2018 – 2024. Measurable rainfall also occurred on four of the last seven New Year’s Eves in the nation’s capital.

As a whole, 2025 will finish as a drier than average year with a rainfall deficit of more than 6” at National Airport. This will be DC’s third consecutive drier than average year. Despite an unusually cold December in the nation’s capital, this year will also finish as DC’s tenth consecutive warmer than average year due to a very warm March, April and July.