How Does June 2020 Stack Up ?

This June has been a fairly typical weather month in the Nation’s Capital.  No extreme weather occurred and there has been a near average amount of rainfall.  Yesterday was the sixth day of 90° since June 1 and Washingtonians could experience a few more before the calendar changes to July.

June is typically DC’s third hottest month behind July and August.  However, five of DC’s 10 warmest June’s have occurred just since 2010.  This June will finish more than a degree warmer than average for an 11^th consecutive year.  The warmest temperature so far this month was 93° on June 3 and June 27.  DC’s coolest temperature so far this month was 54° on June 1. 

Rainfall was near average this month with 3.49” to date.  That’s close to DC’s June average of 3.78” with the prospect for more showers and thunderstorms this afternoon.  Two of DC’s wettest five June’s have occurred just since 2013.  Washingtonians also experienced the third driest June on record in 2017.

This month shares some similarities with June 2016.  That month also finished 1° warmer than average and had five 90° days – close to June 2020 on both measures.  The first 90° heat of 2016 didn’t occur until June 11 much like the first 90° of 2020 didn’t occur until June 3.  That’s compared to DC’s average first 90° day on or around May 18.  DC’s monthly rainfall was also within 0.1” of average in June 2016.

While DC went on to experience one of its hottest three-month periods on record from July 2016 through September 2016, it’s too early to make that comparison for the rest of the 2020 summer.  Although NOAA’s outlook for July is for a warmer and wetter than average month in the DC Metro Area, that is not based on what June’s weather has been like.  Having a warmer than average June isn’t a reliable predictor of the upcoming summer.  For instance, July 2014 was a cooler than average month in the Nation’s Capital and followed a June that was 2° warmer than average.  

The 2010s were a very warm decade in the DC Metro Area and Mid-Atlantic Region.  It will be interesting to look at NOAA’s new 30-year temperature and rainfall averages when they’re released next year.  The period NOAA uses will be updated to reflect 1991-2020, instead of the current 1981-2010 time period.