IAD snow-depths ?!?

[gymengineer]

So famartin commented in the followup to the 3/16-17 crusher about how DCA, IAD, and BWI all reported similar snow depths at 12Z Monday with such different snow totals. 

 

IAD has been pretty strange in how their snow depth sometimes drastically vary from their snow totals in the larger storms. For 2/5-6/10, LWX decided to use their own number from Sterling for the snow total- 32.4", but that yielded a gigantic disparity in snow depth at 12Z Sunday, 2/7/10, that didn't exist at the other two airports. DCA's snow depth on Sunday morning *was* its snow total for the storm.The snow depth at IAD on Sunday morning was eleven (!) inches less than the Sterling snow total. 

 

This season, all the big storms at IAD had 12Z snow depth measurements that raised eyebrows when compared to the snow totals. 

 

1/21: 8.5" snow total ending by midnight with temps in the teens falling to the single digits. In the morning, at 12Z, voila- 5" snow depth. The snow total was likely too high, but a 40% reduction on the snow depth is pretty ridiculous. 

 

2/12-13: 13.1" snow total, the bulk of which fell by sunrise on 2/13. How in the world was IAD reporting only a 7" snow depth at 12Z? We know there was more accumulating snow in the late afternoon/evening from the ULL, but not enough to account for such a low number at 7 am.

 

3/16-17: 11.1" snow total, with a 12Z report of 8", while DCA was reporting a 7" snow depth on a 7.2" snow total. Hmmm...

[needbiggerboat]

I was looking at Feb 10 snow depths earlier and noticed the same thing. No chance it's accurate.