Trenton, NJ (Mercer) The National weather service in Philadelphia has issued a Winter storm watch for Mercer County from Sunday afternoon 4:00 Pm to Tuesday 1:00Am. Heavy snow possible. Total snow accumulations over 7 inches possible. Winds could gust as high as 50 mph creating significant blowing and drifting of snow. Snow will develop west to east late Sunday and last through late Monday or early Tuesday. A period of wintry mix or rain could occur Sunday night and Monday morning, especially along and near the coast, before turning back to snow Monday afternoon. The highest snowfall rates are most likely to occur late Monday.