Strong Nor’easter Friday through Sunday
A large and strong early season nor’easter will impact southern New England mainly in the Friday through Sunday timeframe but may not fully leave the area until late Monday or Tuesday. There’s little doubt that this will be a slow-moving/long duration storm, which will exacerbate the various impacts. Impacts from this storm will include very rough seas, shoreline erosion, coastal flooding, strong winds, and swaths of heavy rain. There still remains some uncertainty in magnitude and timing of greatest impacts, as some variations remain in the projected storm track.
Synoptic Set-up
There continues to be a gradual convergence in the model solutions, all deterministic models curl the surface low center to the west prior to reaching southern New England. The challenge is that a few models curl the low sooner (i.e., further south) and focus the peak streak of the low-level jet closer to the New Jersey coast than southeast New England. This was particularly evident in the 1200 UTC NAM, which mirrors fairly closely prior ECMWF runs. Other models bring the low center much closer to southeast New England before curling to the west. And to make the forecast still a little more challenging, the 1200 UTC run of the UKMET has notably slowed the progress of the surface low and directs the strongest low-level jet at eastern MA Saturday night through Sunday (when other models start to weaken the system). Thus, the bigger picture remains essentially the same, but differences in details translate to differences in the magnitude and timing of some of the impacts. Nudging a little to the south and west, will project a consensus track that brings the surface low center slowly north to a position of about 100 to 200 miles south of Martha’s Vineyard and a retrogression to the west somewhere south of Long Island and east of New Jersey before weakening and eventually pulling off to the northeast (but probably not really leaving our area until late Monday or early Tuesday). The pressure gradient between the high pressure center to our north over Quebec and the low center to our south will generate strong northeasterly winds. All models depict a large storm with a broad swath of gale to storm force winds to the north and northwest of the low center.
If those models that curl the storm to the west further south toward the southern New Jersey or even Delaware coast should verify, then the hardest hit area for wind, beach erosion, and coastal flooding would be the New Jersey shoreline but still at least moderate impacts for southeast New England given the breadth of this storm.
The following sections will describe in more detail the anticipated impacts for southern New England.
Marine
Small craft operators are recommended to remain in port with secure moorings through at least Sunday. Very rough seas will persist through this weekend. Sustained gale force winds with potentially storm force gusts are expected to develop by Friday afternoon, continue through Saturday, and possibly persist into Sunday. Seas will likely build to between 18 and 25 feet in the coastal waters and possibly as high as 25 to 30+ feet a little further offshore. The large envelope, long fetch, and long duration of strong winds will allow seas to build to dangerous heights.
This storm may interrupt or cause adjustments to ferry service to/from Nantucket, Martha’s Vineyard, and Block Island Friday and Saturday, and possibly even into Sunday.
Coastal Impacts
Areas of severe beach erosion are likely to develop Friday through Sunday along exposed east facing shorelines due to large waves atop elevated water levels crashing onshore over multiple high tide cycles. Even south facing shorelines of MA and RI will be susceptible to beach erosion as large swells come ashore, especially Saturday night through Sunday. Given the long duration of this event, anticipate wave periods to increase. Our experience is that waves with longer periods tend to contain more energy and can have a greater erosion impact.
Minor to moderate coastal flooding is expected along east-facing shorelines, starting with either the Friday daytime or late evening high tide and continuing during successive high tide cycles through Sunday. Minor coastal flooding may persist even to Monday’s early afternoon high tide. Along the south coast of MA and RI, minor coastal flooding is likely around high tide late Saturday through Sunday and possibly even into Monday. Anticipate the storm surge to increase to 2 to 3 feet along much of the MA east coast over the weekend. The astronomical high tide is increasing over the weekend and into early next week (due to the combined gravitational pull of the moon and sun during/near the time of a full moon). Wave runup and overwash may exacerbate coastal flooding along east-facing shorelines exposed to the open ocean. Also, the long duration of this event will likely inhibit the ability of the water to fully evacuate during low tides. The projected retrogression of the storm center to the west may also increase the surge some beyond what’s being modeled, if the storm gets far enough north before making the westward turn. Would continue to advise coastal interests to prepare for up to moderate coastal flooding, especially along those shorelines vulnerable to wave action. It’s still not out of the question that a few of the more vulnerable docks and decks could be damaged by large breaking waves. Coastal residents and visitors are advised to monitor the latest forecasts and any warnings from the National Weather Service.
There is also a high risk for severe beach erosion and at least minor to moderate coastal flooding for the Long Island coast as well as portions further south along the mid-Atlantic coastline – from New Jersey to North Carolina). In fact, there looks to be a somewhat higher risk now for severe erosion and pockets of moderate to major coastal flooding along the New Jersey shore.
Wind
There is a significant risk of damaging northeast winds, especially along/near the MA and RI coast. Preliminary peak wind gust estimates are: 50 to 60 mph over the Cape and Islands, south coastal RI, as well as outer Cape Ann, 40 to 50 mph along the rest of eastern MA, much of RI, and coastal CT, and 30 to 40 mph across central MA and eastern/interior southern CT. The period of strongest winds looks to be Friday afternoon through Saturday night, although a few models still keep fairly strong winds lingering into Sunday. The fact that trees are fully leafed out increases the risk of downed trees and branches as well as associated power disruptions. In fact, the National Weather Service notes from experience that wind gusts of 40 to 45 mph are high enough to bring down branches and cause some power interruptions. Thus, although the greatest risk of damaging wind gusts causing power outages exist near the coast, there may be even well inland high enough wind gusts to cause scattered tree damage and isolated power outages due to the full foliage.
Rain
Total storm rainfall of 2 to 4 inches is expected across much of eastern MA and RI (with isolated higher amounts possible) and 1 to 3 inches across central MA and eastern/southern portions of CT. Lesser amounts are anticipated further to the west. Since this rain will occur over a relatively long duration, the risk of flooding is low except in some prone urban and poor drainage areas should heavier bands of rain pass through.
Tropics
Whereas the Atlantic Basin continues to be relatively quiet with respect to tropical cyclone activity, the eastern North Pacific remains very active. Major Hurricane Polo now looks as though it will approach Baja California this weekend. The remnants of Polo will likely move across northwest Mexico and possibly into the U.S. Southwest, where it could increase the threat of flash flooding this weekend into next week. This could be an important development for this region.
Further west, Tropical Storm Nolo will strengthen into a hurricane by tonight and then to a major hurricane as it moves toward the Big Island of Hawaii this weekend. Nolo is expected to take a sharp left turn to the west but not until getting close enough to Hawaii to cause extremely heavy rain, flash flooding, and mudslides on the Big Island in the coming days. An incredible 20 to 30 inches of rain may fall over the southern half of the Big Island given the combination of rich tropical moisture, storm-related upward motion, and orographic uplift! Nolo will also produce dangerous surf along the Big Island’s southern shorelines. Heavy rain of 8 to 12 inches may fall on Maui as well.
Next Message
Another weather blog message will likely be issued Friday for this early season nor’easter.
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The National Weather Service monitors the weather 24/7 and updates forecasts, watches, and warnings as necessary. For most of southern New England, refer to your local Weather Forecast Office for the latest forecast/warning information at weather.gov/box. For information from other Weather Forecast Offices, go to weather.gov and click on the location of interest on the map.
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Message issued September 24, 2026 by:
Bob Thompson
Retired National Weather Service Meteorologist
