With a major snowstorm setting its sights on New Jersey, eight counties have been placed under winter storm warnings because of heavy snow and dangerous travel conditions expected Tuesday by the National Weather Service. The storm’s main target areas for the biggest snowfall totals include a wide swath of northern New Jersey and some parts of north-central New Jersey, according to the latest forecast maps, which expanded the areas that could get pounded with 6 to 12 inches of snow, and some in line for as much as 12 to 18 inches. These are the latest weather warnings, watches and advisories as…