Above: GFS Forecast for 7 AM Christmas Morning.
Light, mixed precipitation will develop from west to east during the late morning and afternoon today. Precipitation will include light snow, sleet & freezing rain & maybe some plain rain along parts of the shore. Any snow accumulation will be minimal (maybe a dusting/coating, up to an inch or so in the northwest hills of CT. Several inches possible in the Berkshires), however some icy spots will develop later today because of the freezing rain. Highs 28-36 today. Freezing rain & rain will taper off during the first half of tonight, then redevelop by Saturday morning. Lows tonight in the upper 20's-low 30's. Lingering areas of freezing rain Saturday morning (where they exist - especially the valleys) will gradually change to plain rain during the day. Precipitation will taper to occasional showers in the afternoon, followed by another wave of rain during the first part of Saturday night. Temperatures will probably stay in the 30's in most places during the day Saturday, then rise into the 40's early Saturday night south & east of Hartford, CT (maybe hit 50 on Long Island/southeast CT?). Clearing late Saturday night (especially after midnight). Lows 26-33 toward daybreak Sunday. Mixed sun & clouds Sunday. Highs 36-42. Looks like the combination of a mid-level short wave and a surface low tracking southeast of Cape Cod will bring 2"-4" of snow to the region just in time for Christmas Eve (Sunday night) and Christmas Morning (Monday). Mixing with rain could keep the amount lower from Groton, CT, east along the RI coast and across Cape Cod.