Snowfall forecast shifts south: Whiteout conditions, strong winds, flooding expected Tuesday

In a matter of 24 hours, the forecast for snowfall has dramatically shifted due to a more south storm track. There’s a sharp cutoff on snow totals in central and northern Massachusetts, with the highest snowfall expected farther south and along the South Coast, Cape and islands. The impacts from the wind and coastal flooding remain the same. 

Storm timing

The worst of the snow continues through mid afternoon. The snow tapers off after 3 p.m. as the storm quickly heads out to sea by dinnertime, and that's when the last snow exits eastern Massachusetts. Tuesday night we clear out, but watch for everything to ice over as temps drop to the 20s.

Snow accumulation in Mass., Conn. and RI

With snowfall rates of 1-2 inches per hour south, we expect whiteout conditions. Boston, Hartford, Framingham will see 3-5 inches. Southern Connecticut, most of Rhode Island, to Bristol and Plymouth counties in Massachusetts will get around 6 inches. Cape Cod and the islands about 6-8 inches. About 1-2 inches are expected for the Merrimack Valley, 2-4 inches for Worcester County, and the Berkshires get around 1-2 inches, with a sharp cutoff to the north. Northern New England misses out on this particular storm.

Strong wind gusts, power outages possible in Mass.

Winds are already gusting 20-25 mph from the east-northeast. The northeast wind strengthens a bit around 30 mph inland and 40-50 mph at the coast by noon. Nantucket could see around 60 mph. Isolated power outages and damage will be found along the coast where we have the heavy, pasty snowfall combined with the winds. 

Coastal flooding in Boston

Our tides are astronomically high due to the new moon this weekend. Wave heights will be around 10 feet offshore with a strong northeast wind, so this will push water onto our coast. Beach erosion and flooding will be a problem this time around. Tuesday afternoon's high tide is forecast to be near moderate flood stage for several places like Boston, Scituate, down to Nantucket. Storm surge of approximately 2-4 feet on top of the high tide is forecast in some spots.  The flooding will be a couple hours before and after high tide, which is around 2 p.m. for Boston. The waves and a northwest wind will remain for the overnight high tide Wednesday at 2 a.m., with tides still running high, so minor flooding is possible. 

Boston's 10-day weather outlook

Wednesday brings us quiet weather with sun, but gusty northwest winds of 30-40 mph. Highs will stay in the 30s for most after morning lows in the 20s and icy conditions. Make sure you have your sunglasses, as it is extra bright! The fresh snowfall allows for extra sunlight reflection (high albedo). Fresh snow and sunshine creates extra bright days. A few minor systems move by the northeast (in from the northwest), and so scattered snow showers continue off and on in the forecast Thursday through the weekend. Temperatures remain in the 30s for the rest of the 10-day forecast.