BOSTON (CBS) – A powerful, windswept nor’easter is on the way to start the volatile month of March. Damaging winds, moderate to major coastal flooding, flooding rains and plowable snowfall are all in the mix.
And, for the first time since the blizzard in early January, we will have “bombogenesis” – signifying an intense and rapidly deepening storm.
With such a large and powerful storm there will certainly be some forecast tweaks and surprises ahead. A small wobble will mean a very large change in impacts across our region.
Here’s how we see it right now:
This storm has the potential to produce a drenching, flooding rainfall for a good portion of southern New England.
Late Friday morning through Friday evening the rain will come down in torrents. A widespread 1 to 3 inches of rain is likely in many areas, causing severe street flooding and urban/poor drainage flooding.
Some rivers may also approach or crest over their banks on Friday and in the days to follow.
This is the biggest wildcard with this storm.
While the first half of the storm will almost certainly be rain, colder air will crash southward Friday evening and overnight changing the rain to a heavy, wet snow.
Highest accumulation amounts will be in the hills of Worcester and in the Berkshires. Snowfall in these areas could easily top 6” before tapering off Saturday morning.
Closer to the coastline, across eastern Mass., there is a bit more uncertainty with regards to how much precipitation will be left after the change to snow occurs. Safe to say, several inches are possible in eastern Mass. Friday night. The real concern is with the heavy, wet nature of the snow combined with strong winds, power outages may become a big issue.
This storm will become an absolute monster southeast of Nantucket on Friday and only slowly pull away farther to the southeast on Saturday. There will be a large and powerful wind field, extending out several hundred miles from the storm’s center.
Cape Cod and the Islands, as well as Cape Ann, are at greatest risk for widespread, damaging winds, ranging as high as 55-80 mph Friday and Saturday.
The rest of eastern Mass. will see winds gusting 35-55 mph, enough to cause tree and property damage and cause some power outages.
This is a long duration wind event, peaking Friday afternoon and evening, and only slowly diminishing on Saturday.
This is a very dangerous and potentially life-threatening event along our coastline, particularly at ocean exposed shorelines from Salisbury to Plymouth.
Unfortunately, this storm is coinciding with astronomically high tides. In fact, the highest tide levels of the month will occur smack dab in the middle of this storm on Friday and Saturday.
Combine that with a persistent and prolonged east – northeast wind over several high tide cycles and you have the recipe for some serious coastal issues.
Widespread moderate to major coastal flooding is likely, starting with Friday morning’s high tide (around 11 a.m.) and continuing through Friday night’s high tide (around midnight) and again Saturday (around midday).
We could see a storm surge as high as 3-to-4 feet, creating tide levels similar to that on January 4th.
The seas will be rough for several days during and following the storm (it is a slow mover) 20-to-30 foot seas are likely just offshore through at least Sunday.
Significant beach erosion is another major concern given the strength and duration of this event.
This storm should not be underestimated. It has the potential to be one of our biggest and most destructive storms in recent memory. Please heed all warnings and stay tuned to updated forecasts throughout the event on WBZ-TV and CBSBoston.com.
Follow Terry on Twitter @TerryWBZ