The first three days of April feature an average high/low combination of 50 degrees. Through yesterday, we're running 5.8 degrees below normal as March (not Smarch, mind you, but March) has reared its chilly head for a few days. In fact, the last couple of days have featured the coolest highs on this particular day since 2004 (on Tuesday) and 2005 (yesterday). That trend towards milder begins today after this chilly note has been established.
Going back to 1940, it's the ninth coolest start to April in Philadelphia and the coolest start to April since 1992 when we averaged just 41.8 degrees. The coldest start in the first three days and since the move of the climate site to the Airport was made in 1940 was back in 1965 when we averaged only 37.2 degrees over the first three days of the month.
Granted, three days does not a month make but it's a clear indicator of a chilly airmass in place...and one that's rather cold for this time of the year compared to the norm. It's not historic cold or anything close...but it's still darn chilly for this late in the Spring compared to what we should get.