A coastal storm will bring a wintry mix of precipitation to New England today on the last full day of winter. The precipitation will begin as snow in the early morning hours, and continue through sunrise. Snowfall will be moderate to heavy at times, leading to an accumulation of 3 to 6 inches through mid-morning. At that point, the precipitation will change briefly to sleet (falling ice pellets), before changing over to a cold rain for the remainder of the day. While the changeover to rain will likely lessen the hazard associated with this winter storm, the early snowfall could put a damper on the morning commute. At the time of this writing, the National Weather Service had issued a Winter Storm Warning for the Boston/Cambridge area, which was to be in effect until 11:00 a.m. today.
Rain is expected to end overnight. After the storm, the vernal equinox will occur at 7:02 a.m. tomorrow morning. This exact moment — at which the tilt of the Earth will be such that the equator directly faces the sun — will mark the end of winter and the official beginning of spring.