DC's summer preview

 

A fine spring day in suburban Washington, D.C.

This month is finishing on a very warm note in the nation's capital. Today could become the first 90° April day in seven years since a record-tying high of 91° on this date in 2017. DC averages only one 90° April day every three to four years, based on NOAA data over the last 30 years.

April 2024 will finish as a warmer than average month in the nation's capital. Depending on how warm it gets today and tomorrow, this month could rank among DC's Top 10 warmest April's on record. That's notable since four of DC's 10 warmest April's have occurred in the last 14 years. 

What makes this month different is how streaky temperatures and rainfall have been. April got off to an unusually chilly start with below average temperatures on six of the first seven days of the month. That was followed by 11 consecutive warmer than average days, including April 15 that featured a high/low of 83°/63°. Seven of the following nine days, through April 27, were cooler than average in the nation's capital.

That's brought us to this June-like weather pattern to finish the month with several days in the 80s or higher. Unlike June, however, this week's temperatures will lack the muggy conditions that often accompany DC's summertime heat.

While it could reach 90° in the nation's capital this afternoon, it isn't a sure thing given National Airport's proximity to the Potomac River. If the wind direction is blowing from the south off the chilly water, then temperatures at the airport, DC's official weather reporting site, remain a few degrees cooler than downtown areas. While a south wind pumps more humid air into the nation's capital during the spring and summer, DC's hottest days occur when a more westerly wind occurs.

April 2024 will also finish as a drier than average month in the nation's capital. That's despite 1.68" of rain, more than half of DC's April rainfall average of 3.21", during the first week of the month.  Only 0.38" of rain has fallen since then, for a monthly rainfall total of 2.06". Despite the below average rainfall this month, no drought conditions exist in the DMV given how wet 2024 has been so far. The nation's capital has a yearly rainfall surplus of 2.29" since January 1.

Warmest April’s in Washington, DC (Source: NOAA)

1. 63.8° (2017)
2. 62.4° (2019)
3. 62.1° (2023, 1981)
5. 62.0° (1994)
6. 61.6° (1985)
7. 61.2° (1960)
8. 60.9° (2010)
9. 60.6° (1941)
10. 60.1° (1980, 1977)