May 2023 gets underway

 

Nationals Park, Washington, D.C.

April 2023 finished as DC’s third warmest on record. It was also DC’s first warmer than average April since 2019. Despite a drier than average start, it also finished as a rainier than average month after its very wet final week. 

Average daily temperatures in May, the third and final month of “meteorological” spring, will warm appreciably in the nation’s capital. Daily average temperatures in the nation’s capital range from a high/low of 73°/54° on May 1 to 80°/63° by the end of the month. DC’s hottest May temperature on record of 99° occurred on May 31, 1991. Meanwhile, DC’s coldest May temperature of 33° occurred long ago on May 11, 1906. 

DC’s May weather can also be quite streaky. For example, while 10 of the last 20 May’s have been cooler than average, four of DC’s 10 warmest May’s have occurred since 2004. By comparison, two of the last three May’s have been cooler than average in the nation’s capital, following DC’s very warm May’s in 2018 and 2019. 

May is DC’s third wettest month of the year according to NOAA, with an average monthly rainfall total of 3.94”. Rain can accumulate quickly in the Nation’s Capital this time of year as May 2008 illustrated. That was DC’s third wettest May with 10.66” of rain and an incredible total of five days with an inch or more of rain. Washingtonians saw 16 days with rain in May 2008 and the frequent cloudiness and rainfall helped suppress temperatures. May 2008 finished 2.5° cooler than average.

May is an active severe weather month in the DC Metro Area.  Looking at DC’s May climate records, one can see that on several dates a trace of snowfall (enough to accumulate, but not enough to measure) has occurred.  Except it wasn’t actually snow, but hail.  For example, on May 2, 2016 a severe weather outbreak produced a lot of hail in the DC Metro Area.  Small accumulations of hail were reported in spots such as at National Airport where a “trace” of frozen precipitation was observed.

Although summer doesn’t officially arrive until June, May often features summer-like heat. The nation’s capital has averaged between 1 and 2 May days with highs in the 90s over the last 30 years. While no triple-digit May heat has been observed in the Nation’s Capital, DC residents can expect to see a high of at least 95° roughly once every 4 to 5 years. NOAA’s Climate Prediction Center expects May 2023 to feature near average temperatures and rainfall in the nation’s capital.