Unofficial Arrival of Spring

 

 

National Harbor, Maryland

February 2023 finished as the third warmest in the Nation’s Capital and followed the third warmest January.  These two months combined for D.C.’s warmest January-February on record.  Last month also featured only the fourth occurrence of 80° February warmth in the Nation’s Capital with a record high of 81° on February 23.  It was also a drier than average month with below average rainfall and snowfall.  The 2022-2023 winter season saw less than 10% of the snowfall average in the Nation’s Capital with only 0.4”.

Meteorological spring got underway yesterday and continues through the end of May.  Average daily high/low temperatures rise dramatically this month from 52°/35° on March 1 to 62°/43° on March 31.  There has been an even 50/50 split of warmer and colder than average March’s over the last 20 years in Washington, D.C.  However, five of the last six have been warmer than average.  D.C.’s warmest March temperature on record is 93° on March 23, 1907.  By comparison, the coldest March temperature in the Nation’s Capital remains 4° on March 4, 1873.

Despite the warming March temperatures, accumulating snowfall can still occur at any point.  It just becomes less common as the month wears on.  As recently as 2018, Washington, D.C. saw 4.1” of snow as late as March 21.  March has been DC’s snowiest month of the year four times over the last decade.  According to NOAA, March is the only month of the year DC’s snowfall average has increased in the last 10 years having risen from 1.3” (1981-2010) to 2.0” (1991-2020).

Although only five of the last 20 March’s have had above average snowfall in the Nation’s Capital, accumulating snowfall has occurred in 13 of them.  Longtime Washingtonians may remember March 2014 was DC’s snowiest since 1960 with 12.7”.  By comparison, March has also been a drier than average month 12 times over the last two decades.  DC residents average 3.5” of March rainfall (including liquid equivalent of melted snowfall).  Precipitation is important in March as it sets the stage for the start of the growing season.

This helps illustrate how streaky March weather can be in the Nation’s Capital.  Unusual warmth, such as during much of this January and February can be followed by unusually cold weather.  A good example of this occurred in 2017.  February 2017 finished as DC’s warmest on record and was followed by a very warm first 10 days of March that saw six days with highs of at least 60°.  However, the middle third of that month was unusually cold with lows in the 20s on seven consecutive days starting March 11.  NOAA’s outlook for this March is for the potential of below average temperatures combined with near average precipitation.