It's Actually the Precipitation Fields

The low track looks fairly consistent from model to model, but the strength of the low that develops after phasing is intense.  The models have responded by extending the precipitation field southward.  New model runs coming in now...but the midday runs aren't usually the most accurate.

Still, most models have us in the 8-12 inch range and this is looking more likely.

Oh - and just as I was typing this, the NWS has put us under a Winter Storm Warning.

In the text it warns of 10-20 inches...the lower end of that range happens the further south you go.  So in Arlington, that argues for 10-14 inches.

Still trying to sort it all out - but right now, significant snowfall - at least 8-10 inches and possibly a foot or more seems probable for a time period beginning tomorrow afternoon and ending in the afternoon on Wednesday.

QPF Plot for this storm.  I expect ratios slightly above the 10:1 rule...