N.J. weather: When will the snow start falling today? Update on snowstorm timing, snowfall totals. Updated Dec 16, 2020; Posted Dec 16, 2020 The National Weather Service forecast is calling for up to 18 inches of snow for parts of New Jersey starting Wednesday into Thursday.National Weather Service Facebook Share Twitter Share New Jersey’s first major snowstorm of the year is expected to begin early Wednesday afternoon and last until Thursday morning, according to the latest forecast updates on timing. A much-discussed storm that appears poised to blast northern counties with a foot or more of snow is likely to start in South Jersey late this morning before working its way northeast with the first flakes flying in Central Jersey as early as 1 p.m. and in North Jersey around 3 p.m. or 4 p.m., according to forecasters.