DC’s unusually warm March weather

 

More like spring (March 2020)

The nation’s capital has experienced seven of its 15 warmest March’s since 2010. March is a transitional weather month with the greatest extremes between monthly record high and record low temperatures.

March’s highly changeable weather has been on full display across the DMV (DC, Maryland and Virginia) over the last week. Not only did the nation’s capital set record highs on March 10 (84°) and March 11 (86°), but those were DC’s warmest temperatures during the first half of March since 1990. Severe weather also occurred in the DMV twice over the last week as this month’s battle between winter and spring continues.

The nation’s capital averages one 80-degree March day in two out of every three years, according to NOAA. However, between DC’s three 80-degree days last March and the two so far this March, Washingtonians have already had more 80-degree March warmth than in any back-to-back March period since 1993. That combination, combined with four of DC’s 15 warmest March’s over just the last decade illustrates a recent pattern for warmer March’s.

While some of that warming can be attributed to the urban heat island effect and increased automobile traffic, a warming climate is also a factor. NOAA uses a 30-year dataset when measuring average temperatures and precipitation for the United States that’s updated every decade. NOAA updated its averages five years ago to reflect the 30-year period of 1991-2020, replacing the previous 1981-2010 period. Since the 2010s were a much warmer decade than the 1980s, DC’s average temperatures for the entire year increased, not just in March.

The recent warm weather doesn’t mean Washingtonians won’t see colder or snowier than average March weather going forward. For example, March was DC’s snowiest month of the year five times between 2009-2018. That helps underscore how March weather can fluctuate significantly from one year to the next.

DC’s warmest March’s (Source: NOAA)

1. 56.8° (2012)
2. 56.2° (1945)
3. 55.5° (1921)
4. 54.3° (2025)
5. 53.5° (2016)
6. 53.2° (2020)
7. 53.0° (1946)
8. 52.7° (1977)
9. 51.9° (2024)
10. 51.7° (2000)
11. 51.5° (1979)
12. 51.3° (1976)
13. 51.2° (2021, 2010, 1910)
 
47.6° - Average