SUBJECT: Upcoming Winter Storm Wednesday/Thursday (Update #3)
The National Weather Service is forecasting another coastal storm to bring rain, snow, and gusty winds to New England starting Wednesday morning and continuing into Thursday.
- Forecast snowfall totals have decreased since this morning, especially east of Rt. 495.
- Precipitation is forecast to overspread the state from west to east starting mid-morning Wednesday, reaching Worcester by 11:00, the Boston area by noon, and Cape Cod by 1:00 PM, and continuing through Wednesday night before tapering off Thursday morning. The most significant commuting impact will be during the Wednesday evening commute and possibly lingering into the Thursday morning commute.
- Precipitation will fall as all snow over much of central and western Massachusetts and as all rain with possibly some wet snow at the beginning in the Cape and Islands. A change to rain is expected Wednesday evening over much of eastern MA, with the rain/snow line most likely setting up just to the north and west of the I-95 corridor. Snowfall will be wet and heavy, especially near the rain/snow line.
- Snow may fall at a rate of as much as 2-3 inches per hour at the peak of the storm (roughly 2-3 PM Wednesday afternoon to 8-9 PM Wednesday night).
- Snowfall totals could reach 12-18 inches in much of western and central Massachusetts, with locally higher amounts possible over high terrain such as the eastern slopes of the Berkshires and the Worcester Hills.
- Snowfall totals will drop off rapidly in the vicinity of the rain/snow line. 4-8 inches of snow are predicted for the Boston-Providence corridor, 1-3 inches in the metro Boston area, and up to 3 inches over Cape Ann and southeastern Massachusetts.
- Much of Plymouth County, the South Coast, and the Cape and Islands will see little if any snowfall accumulation.
- 30-40 MPH wind gusts in the interior and 50-60 MPH gusts over the immediate coast are forecast, with the strongest winds occurring Wednesday night into Thursday morning.
- There may be minor to moderate coastal flood and erosion impacts for the early Thursday morning high tide (generally 3:30 AM to 4:30 AM along the MA east coast). Fortunately, the astronomical high tides will be much lower than they were for the last storm and that will help mitigate potential impacts. Also, this storm should be progressive enough to just impact one high tide cycle.
- In spite of relatively low astronomical high tides, the surge and wave action from this storm may be enough to produce minor to moderate coastal flooding and beach erosion for the Thursday early morning high tide along the Massachusetts east coast from Salisbury along the New Hampshire border to Cape Ann, including the Plum Island area. Along this reach of coastline, we may experience a storm surge of 2.5 to 3 feet and large waves of just over 20 feet approaching the shoreline. And the expected surge and wave action will be coupled with a more vulnerable coastline.
- Elsewhere along the Massachusetts east coast, we anticipate a potential storm surge of 2 to 2.5 feet and waves a little offshore of around 15-20 feet. This may produce minor coastal flooding and some beach erosion along the ocean exposed coastline from Hull to Plymouth as well as the north and northeast facing shorelines of Cape Cod and Nantucket.
- There are still a few areas where water has yet to drain from the high tides during last weekend’s storm. These floodwaters will probably persist until sometime after the Thursday early morning high tide.
- While confidence is increasing, especially regarding snowfall, a slight shift in the storm track will ultimately determine where the rain/snow line ends up.
- Coastlines in general will be more vulnerable to coastal flooding and erosion impacts due to the damage caused by last weekend’s storm.
- Minor to moderate coastal flooding and moderate beach erosion are possible along the Massachusetts coast from Salisbury to Cape Ann during the Thursday morning high tide. There is a risk for significant erosion along portions of Plum Island and Salisbury Beach.
- Minor coastal flooding and minor to moderate beach erosion are possible along the coast from Hull to Plymouth, as well as the ocean side of Cape Cod from Wellfleet to Chatham, and Nantucket (both the east side and Nantucket Harbor area) during the early Thursday morning high tide.
- Heavy snowfall (up to 2-3 inches per hour) during the peak of the storm Wednesday afternoon and evening west of Rte. 495 will make travel extremely difficult or even impossible at times due to slippery road conditions and lowered visibility. The Wednesday evening commute will be severely impacted, and the Thursday morning commute may see some impacts as well.
- Heavy wet snow may result in downed tree branches/limbs, increasing the risk for power outages.
- Gusty winds may cause scattered tree damage and isolated power outages, especially in eastern Massachusetts.
- Areas of eastern and southeastern Massachusetts that receive heavy rain Wednesday afternoon or evening may experience flooding of rivers, streams, and urban areas.