The 2016 non-blizzard Blizzard
AP reporting on the controversy.
The two vicinity sites mentioned in the article are ~3 miles NNW (Adams Morgan neighborhood) and ~5 miles NW (Dalecarlia Reservoir) distant from DCA.
Meanwhile ... ~2 miles across the river to the east in Anacostia ... MD ... a trained spotter reported 19" and about the same distance to the SSE a 17" report from National Harbor ... VA.
Apparently ... DCA reported 17.8" STP (1.47 liquid) yet IAD and BWI measured 29.3" (2.63 liquid) and 29.2" (2.13 liquid) ... respectively.
This disparity has lead to questions about how much snow actually fell @DCA.
NWS vicinity reports in the PNS bulletin also suggest a possible under-measured of snow at Raygun/National.
Reported snow liquid ratios (SLR)
FAA contract personnel measure snowfall at many major airports. May be one reason why so many SLRs are 10:1.
That ... and not being able to find the snowboard when it's time to measure.