Significant Weather Blog: Wednesday, October 8, 2025 6 PM
FREEZING TEMPERATURES LIKELY ACROSS MOST OF INTERIOR SOUTHERN NEW ENGLAND LATE THURSDAY NIGHT AND EARLY FRIDAY MORNING
RISK OF COASTAL FLOODING AND BEACH EROSION ALONG PORTIONS OF THE MASSACHUSETTS COAST SUNDAY AND MONDAY
Freezing Temperatures Thursday Night
After a stretch of typical mid to late summer temperatures, interior southern New England will likely experience the first night of freezing temperatures Thursday night into early Friday morning. A Freeze Watch is in effect for most of southern New England away from the immediate coast. Surface high pressure moving over the area will provide excellent radiational cooling under clear skies and light winds Thursday night, and temperatures across interior southern New England will drop into the upper 20s and lower 30s overnight. This is expected to be the area’s first widespread frost/freeze event. Plants sensitive to temperatures near or below freezing may be at risk and require protective action.
Coastal Storm
All numerical weather prediction global models, including both operational and ensemble runs, depict surface low pressure development off the North Carolina coast by the weekend. This is in response to a vigorous short wave upper trough moving southeast from Canada interacting with a weaker upper trough languishing over the southeast U.S. Confidence is very high in the formation of this coastal storm but much lower as to how far north it will drift. There remains considerable spread in the various model ensemble runs as to how far this system will track north, although most operational model runs have shifted further north to an extent in the past 24 hours. It remains to be seen if this trend continues. Also, there is a possibility that this storm could acquire some subtropical characteristics even if still treated as an extratropical (or nor’easter) type system.
The most significant potential impact from this system would be strong onshore easterly winds causing areas of coastal flooding and beach erosion from the Carolinas north to Delmarva, New Jersey, and possibly as far north as southern New England in the Sunday through Monday timeframe. We are experiencing “King Tides” due to the juxtaposition of the Moon and Sun through Friday with the Thursday afternoon high tide at Boston Harbor predicted to be 11.9 feet above mean lower low water (MLLW). Onshore winds producing a storm surge and wave action will not affect southern New England until Sunday afternoon when the astronomical high tide is not as high but still elevated (10.9 feet above MLLW at Boston Harbor). Slow movement of this coastal storm may delay the strongest winds and higher wave action until late Sunday night or Monday. The Monday early morning high tide is only 9.2 feet above MLLW, and the late Monday afternoon astronomical high tide is predicted to be 10.4 feet above MLLW. Although the tides are not as high on Monday, the duration of relatively strong onshore winds and continued wave build-up could result in at least one or two more episodes of minor coastal flooding and beach erosion along exposed shorelines, especially with an east exposure.
This will probably in the end be a fairly minor event, although successive erosion episodes are always a concern. It is noteworthy that a difference in timing on the order of just 2 or 3 days when the astronomical tides would have been higher could have made a major difference in impact. We may have indeed dodged a bullet.
Next Message
Greater clarity is expected in the track (in particular how far north) of this storm over the next day or two and this message will likely be updated either Thursday or Friday to provide more detail on potential impacts.
About this Blog and Disclaimer
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. For the latest information on Atlantic basin hurricane activity, access the National Hurricane Center website at nhc.noaa.gov.
A blog is issued when there is a potential risk of hazardous weather to southern New England and serve to provide background information regarding the significant weather with somewhat of an educational slant. In the case of hurricanes, the author will attempt to issue a message when any portion of the United States coastline may be seriously impacted. It’s intended to complement and not serve as an alternative to official forecasts issued by the National Weather Service. Readers are urged to check National Weather Service forecasts and warnings for the most timely and updated weather information. This weather message is solely produced by the listed author and does not constitute an official product of the Blue Hill Observatory and Science Center (BHOSC).
The frequency of this blog will depend upon the nature of the weather threat and availability of the author. Thus, for the latest information on weather forecasts and warnings, refer to the National Weather Service, which monitors and forecasts the weather 24/7.
Blue Hill Observatory and Science Center (BHOSC)
The BHOSC maintains a continuous daily observation record that dates from February 1, 1885 without interruption and provides educational information on weather and climate to area students and the community at large. Your support of BHOSC is much appreciated and enables this nonprofit organization to maintain the long-term climate record at the Blue Hill Observatory (longest continuous record in North America) and provide valuable educational resources on weather and climate via outreach to schools, site visits/tours, webinars, and conferences. For more information on the Blue Hill Observatory and Science Center, explore bluehill.org.
Message issued October 8, 2025 by:
Bob Thompson
Retired National Weather Service Meteorologist
Blue Hill Observatory and Science Center Board member
