DEDHAM, Mass. — A powerful fall nor’easter is expected to impact Massachusetts beginning Friday and continuing through the weekend, bringing hazardous coastal conditions, strong winds, and periods of heavy rain.
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Inland locations will see wet, windy weather, but the greatest concern remains along the coast, where flooding, beach erosion, and large waves could cause significant impacts.
Coastal impacts are the biggest concern
A coastal flood watch and high surf advisory are in effect from Friday through Sunday as the storm churns offshore.
Forecasters expect waves ranging from 6 to 17 feet, with powerful surf battering the Massachusetts coastline through the weekend. Minor coastal flooding is expected during each high tide cycle, with up to one foot of inundation possible in vulnerable areas.
Moderate to potentially severe beach erosion is also anticipated due to the combination of large breaking waves, prolonged onshore winds, and elevated surf.
Strongest winds Friday into Saturday
Winds will steadily increase Friday before peaking Friday night into Saturday.
Along the coast, sustained north to northeast winds of 15 to 30 mph are expected, with gusts reaching 50 mph. The strongest winds are expected across Cape Cod and the Islands, where some gusts could approach 60 mph.
Communities farther inland will still contend with gusty conditions, with gusts generally ranging from 30 to 40 mph. While the risk for widespread wind damage or power outages inland appears lower, isolated tree damage and scattered outages remain possible.
Sunday is expected to remain windy, though wind speeds may not reach the same warning-level criteria seen earlier in the storm.
Rain arrives Friday, continues through the weekend
The first rain is expected to reach southeastern Massachusetts Friday afternoon.
Forecast confidence is lower around Boston, where rain may develop during the afternoon but is not guaranteed. Locations north and west of the city are more likely to remain dry until Friday evening or overnight.
Once the rain arrives, steady and at times heavy rainfall is expected to continue through the weekend before gradually tapering off Monday as the storm slowly pulls away from New England.
Current rainfall projections call for:
- 1 to 2 inches across inland communities
- 2 to 6 inches along the coast, Cape Cod, and Islands
While exact totals may change, the storm’s prolonged nature means rainfall could accumulate significantly in some locations.
Flooding risk remains limited
Despite the potential for several inches of rain, flash flooding is not expected to be a major threat at this time because the rainfall will be spread out over multiple days rather than falling all at once.
However, localized ponding on roads, poor-drainage flooding, and reduced visibility during heavier rain bands are likely throughout the weekend.
Timeline: When conditions deteriorate
Friday
- Clouds increase
- Rain develops across southeastern Massachusetts during the afternoon
- Winds begin strengthening
- Coastal conditions worsen
Friday Night Through Saturday
- Heaviest rain and strongest winds
- Coastal flooding concerns increase around high tides
- Large waves and dangerous surf continue
Sunday
- Continued rain and gusty winds
- Coastal flooding and erosion concerns remain elevated
- Storm gradually begins to weaken
Monday
- Rain tapers off
- Winds slowly diminish
- Improving conditions expected through the day
Bottom line
Massachusetts is just a day away from a prolonged weather event that will bring impacts well beyond a typical rainy weekend.
Inland locations should prepare for several inches of rain and strong wind gusts, but the most serious threats will be along the coast, where large waves, repeated high-tide flooding, and significant beach erosion could create dangerous conditions from Friday through Sunday.
Residents are urged to monitor the latest forecasts and avoid coastal areas during periods of rough surf and high tide as the nor’easter moves through New England.
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