BOSTON (CBS) – Some minor changes overnight have led to a much greater anticipated impact for parts of eastern Massachusetts.
Chief among the updated hazards for this nor’easter include increased snow accumulation projections, a slightly longer duration event and new coastal flood warnings issued.
This will be a significant blow to all of southern New England.
Heavy, wet snowfall, damaging coastal winds, numerous power outages and another round of coastal flooding are all anticipated in the coming 24 hours.
Conditions will deteriorate very rapidly Wednesday afternoon and evening.
If you don’t have to travel after 2 p.m., we would urge you stay at home. Visibility could be reduced to near zero, whiteout conditions for a time during the height of this storm between 3 p.m. and midnight.
Now to the details.
By 3 p.m. the rain and snow will have filled in across the region. The rain will be getting heavy inside I-495 and over southeast Mass. and the snow will be ramping up as well in areas west of 495.
Accumulation: Very little, if anything yet
Wind Gusts: 15-30 mph at the coast
Coastal Flooding: High tide is between 3 and 4 p.m., pockets of minor flooding, nothing too significant
Travel Impact: Low but heading downhill fast
By 6 p.m. it will be snowing heavily (in bands) just about everywhere west of I-95, and very close to Boston. Snowfall rates of 1-to-2 inches per hour in places will lower visibiliy significantly and create snow-covered roads tough to keep up with.
Accumulation: 2-to-4 inches west of 495, coating to 2 inches west of I-95
Wind Gusts: 20-40 mph coastline, up to 50+ Cape/Islands
Coastal Flooding: Tide going out, no issues at this time
Travel Impact: High
By 9 p.m. it will now be snowing in just about all of southern New England except for the South Coast and Cape and Islands. Intense snow bands will continue to rotate in off the ocean, creating very hazardous travel and near whiteout conditions. Precipitation may begin to decrease or end over Cape Cod due to a dry slot approaching with the center of the storm.
Accumulation: 5-to-10 inches in Worcester County, 4-to-8 inches closer to 495 and 128, Coating to a few inches near the coast from Boston to immediate North and South Shore
Wind Gusts: Up to 60 mph over Cape Cod/Islands, up to 50 along the entire coastline, up to 40 inland/eastern Mass.
Coastal Flooding: Low tide, no issues
Travel Impact: Severe
By midnight the center of storm now moving past our latitude and winds/snow bands changing direction (more northerly). The precipitation tapers off up to about Boston, final bands of heavy snow rotating through areas west of I-95
Accumulation: 8-to-12 inches + in Worcester County, 6-to-10 inches + around 495 and 128, 3-to-6 inches on the immediate coastline near Boston and immediate North and South Shores.
Wind Gusts: Again, now from the north, up to 50 mph along the coastline, peaking over Cape Ann, 25-35 inland
Coastal Flooding: Tides start coming back in, still no serious issues
Travel Impact: Severe west of I-95
By dawn Thursday, there will be just a few leftover snow showers, mainly north of the Mass Pike. The meaningful snow accumulation is long over.
Coating – 1 inch: Most of Cape Cod, Islands
1-to-3 inches: South Coast and Coastal Plymouth County
3-to-6 inches: Farther north in Bristol/Plymouth counties and up through Boston and the immediate North Shore to Cape Ann
6-to-12 inches: All areas west of I-95 including most of 128 belt and 495 belt (to I-95 interchanges)
12 inches+ There could be some areas that receive a bit more than a foot (perhaps 14 or 15 inches) if some intense banding happens later Wednesday night as the storm start to pull away. Right now we think the best chance of this happening may be right around the 495 belt from Amesbury to Marlboro and areas just to the west in parts of Worcester County.
Winds will have shifted to the north-northwest and will be decreasing during Thursday.
The high tide of greatest concern is between 3-4 a.m. Thursday. We anticipate widespread minor to pockets of moderate coastal flooding during this tide cycle for all east-northeast facing shorelines.
Seas just offshore will be 20-25 feet and a storm surge of 2-3 feet is also likely. Another round of beach erosion as well.
Unfortunately there will be another round of outages with this nor’easter.
Due mostly to the heavy, wet nature of the snow weighing on power lines and tree limbs combined with a gusty north-northeast wind. Numbers certainly won’t be as high as last week’s storm.
It has been an active, wet stretch as of late and rivers are already near their banks. Another 1-to-2 inches of rain from this nor’easter will once again cause localized flooding of streets and urban/poor drainage areas as well as some minor rivers and streams to crest. This is of course, mainly for southeastern Mass. and the Cape where the storm will be mainly rain.
Well, things quiet down through the weekend, temperatures climb to slightly above average by Saturday and Sunday (mid 40s) and don’t forget, we turn the clocks ahead one hour Sunday at 2 a.m!
BUT, our next potential storm threat comes Monday. It’s way too early to tell if this will be a hit or miss, but it does appear that another sizeble coastal storm will form off the Carolinas late in the weekend. This one MAY stay too far south to hit New England, but still too early to make a call on this one.
As always, we urge that you stay tuned to updated forecasts on WBZ-TV and CBSBoston.com.
Follow Terry on Twitter @TerryWBZ