did you look at the snow totals on that link 5 - 10 inches - less coastal NJ where do you see 20 ?
http://www.raymondcmartinjr.com/weather/2011/NJSnowRaw_20110111.gif
Eastern Bergen ,Eastern Essex and eastern Union should also be under warnings especially since they mention some areas could get 6 inches - they are cutting it to close IMO
IMO Somerset , Middlesex and Mercer Counties which currently only have advisories for 3 - 5 have a 50/50 chance of being upgraded to warnings close to the start of the storm.......
there is a possibility this will turn into a minor event early next week similar to the last few - also the drought is continuing with little precip this month 0.10 inch at CP Norm 1.45