This is very true. While Pres. Day might be about the time limit for a big HECS event, there have been several solid moderate events in late Feb through mid-March or so. More recently off the top of my head (and giving the amount I recorded at my location)...
Feb 27-28, 2003...~5"
Feb 25, 2007...5-6"
March 3, 2009...6"
March 25, 2013...4"
March 2-3, 2014...5-6"
March 17, 2014...8"
March 25, 2014...3"
Feb 20, 2015...6" (unusual cold at the start, later turned to sleet and drizzle)
March 5, 2015...6-7"
March 20, 2018...~5"
May have missed some but those are the ones I most recall.