Measuring snow can often more art than science. On occasion the snow falls straight down and most of the reports in a small area are approximately the same. There is always going to be natural variations, but many times the snow measurements differ because of technique, especially when the wind blows.
Often times we will receive snow totals that may vary by several inches just within Fargo Moorhead. When the wind blows, it tends to blow the snow off your roof and deposit it near your house, so a two inch event often gets measured as 4 inches of snow, especially if the report comes from the backyard deck.
Although the official measurement could be considered an educated guess at times, our official observer through careful observation and years of experience usually gives a very good estimate to our snow fall even for the windiest of events and that total can easily be quite different than what you find on your driveway.