May 2013 at DCA is finalized at 66.7 degrees, the 45th warmest of all-time, vs last year's 71.4 degrees, the 3rd warmest. This year's meteorological spring (March, April, and May) at DCA is finalized at 56.5 degrees, the 43rd warmest. That compares with last year's record-breaking spring average of 62.2 degrees. The 5.7 degree decline from one spring to the next is the second greatest in DC history, topped only by the 5.8 degree decline between 1991's 60.0 degrees and 1992's 54.2 degrees.
Portions of this May had a brisk feel on some days, some folks would say those days felt harsh.
Some folks out for a stroll had winter clothes on. Nor meant to be a scientific comment, personally,
I found those cool days to be refreshing.
RodneyS.: These temperature swings you are documenting can be random noise or can be a
signal of increased volatility. Too soon to say.