Where are the stations located at which the reports were taken from? One major issue with any weather data is the location from which temps/precip/snow/ect are recorded (
Metadata).
Good example is Regan Airport, some brilliant guy had the idea that we should take WX readings from a strip of land jutting out into a wide body of water... main reason why Regan gets 16 inches of snow but the Mall/NW/McLean gets 22 or why it is 85 on an april day in the Mall/NW/McLean but only 75 at Regain (cool water).
... No GW debate whatsoever, just when ya see a discrepancy like this my weather sense kicks in to tell me something is fishy