The last in a long train of storms will bring snow and ice to the Mid-Atlantic and Carolinas on Wednesday. While Washington will be near the northern edge of the storm starting late in the morning — with a dusting to a half-inch of snow possible in the District and areas to the south by the evening — impacts will be moderate to major farther south.

Officials have urged residents to stay off the roads in portions of Virginia and North Carolina, where a storm dropped heavy snow and caused hundreds of accidents in places that