December kicks off tomorrow which is the start of meteorological winter and it will look like winter for a lot of us by day’s end. If you’re doing any post-Thanksgiving travel, try to do that tonight or early Sunday morning. By mid afternoon we’ll have the storm moving into New England. If you’re heading south to New York City or west, you’ll likely encounter that precipitation by mid morning.
Winter Storm Warnings and High Wind Warnings are currently issued for the Midwest where our storm is now. Closer to home, the National Weather Service has a Winter Storm Warning issued for central Massachusetts (pink) where we have our best chance at heavy snow and the highest accumulations. A Winter Storm Watch remains in effect for areas inside of 495 and south of the Pike. In the near future, this will either be upgraded to a Winter Weather Advisory or Winter Storm Warning. It will be dependent on the Weather Service’s thought on sleet potential. More sleet = Winter Weather Advisory. More snow = Winter Storm Warning.
Timing wise, the storm will start Sunday afternoon and evening as snow for just about everyone. Through the overnight hours, we’ll begin to see that snow change to rain and sleet for a lot of us on the coast. Coastal spots south of Boston, the Cape, and the South Coast will be mainly rain after that initial burst of snow. The 95 Corridor will be a tricky forecast. We’ll wobble between rain, snow, and sleet. Our northwestern spots could briefly mix with sleet during Monday, but it is mainly a snow event.
Travel wise, the next few days will be rough — especially for our northwestern spots. Sunday evening will likely be the worst. The snow will come down hard and fast for a bit before changing over to sleet and rain for most overnight. Throughout the day on Monday, most of us inside of 495 will deal with on and off rain and snow. It will now rain or snow all day long and with the intermittent precip, combined with road chemicals, you’ll likely deal with wet roads or a slush at worst. Areas outside of 495 to the northwest may have higher impacts due to the duration of the snow. Southeast Mass and the Cape will likely feel very few impacts through Monday as it will be warm enough for rain and roads will just remain wet.
Below is a timeline of what to expect on the roads. Inland areas will have that initial burst of snow Sunday evening and then light snow will linger on-and-off for much of Monday and taper off Monday night. Coastal spots will have 2 bursts of snow separated by sleet and rain. Snow will start Sunday evening and much of that snow will be washed away by the rain during the day on Monday. As the snow tapers off well inland, areas that are inside of 495 will likely get one more burst of heavy snow very early on Tuesday morning.
Below is our snow forecast map, but keep in mind for a lot of us along the coast, where we see a lot of rain, you probably won’t shovel this much. Mother Nature will wash some of it away with the rain on and off through Monday. Either way, if you do shovel it, take your time. It will be a heavy, wet, water-logged snow. So bend from the knees, not the back!
While the main focus is of course the snow and sleet, there is also a wind concern with it. In fact, the winds are the exact reason for the changeover to rain and sleet. Keep in mind water temperatures right now are about 50 degrees. So as winds turn to the northeast, it’s actually pushing that warmer air over land and turning that snow to sleet and eventually rain for a lot of us. That said, those winds could gust to 40 mph for coastal areas on Monday with 50 mph gusts possible on the Cape.
Thankfully the coastal threat with this storm is low, but unfortunately it’s not zero. The good news is we’re at astronomically low tide right now, so inundation should be minimal. But, with the gusty winds and high breaking waves, we’ll likely see some splash over which could lead to minor coastal flooding on Monday afternoon.