The vernal equinox occurs Tuesday morning, astronomically marking the start of spring. Temperatures are expected to be anything but spring-like, running about 12 degrees below the normal high of 48. In addition, stout northeast winds gusting to 30 mph will add a wintry feel to the day. Still, conditions could be worse. Our blustery lake winds are the result of high pressure to the north, contrasting with a deepening nor’easter along the mid-Atlantic coast. Energy feeding into the developing storm brought baseball-sized hail and possible tornadoes to parts of the South late Monday. As colder air is drawn into this system Tuesday and Tuesday night, heavy, wind-driven snow is expected from the central Appalachians to southern New England, including the cities of Philadelphia, New York, and Boston.