From the National Weather Service:
Low pressure will approach the region later today, bringing a wintry mix of precipitation. The precipitation will reach northern Connecticut into Rhode Island late this afternoon, then will spread across the remainder of the region tonight. Temperatures will start off cold, mainly in the 20s to around 30 away from the coast, which is where the mix of snow, sleet and freezing rain are expected.
The temperatures will slowly rise overnight into early Friday morning, with the precipitation changing over to rain by daybreak across most areas except across N central and western Mass, where a mix of rain and sleet will linger. See graphic for the forecasted totals through early Friday.