Severe Storm Surge ● Closed
Coastal Flood Warning issued September 25 at 7:20AM EDT until September 27 at 8:00PM EDT by NWS Boston/Norton MA, United States of America
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* WHAT...For the High Surf Advisory, large breaking waves of 6
to 13 feet in the surf zone. For the Coastal Flood Warning,
one to two feet of inundation above ground level expected in
low-lying areas near shorelines and tidal waterways (4.2 to
12.8 feet Mean Lower Low Water).
* WHERE...Eastern Essex MA, Suffolk MA, Eastern Norfolk MA,
Eastern Plymouth MA, Barnstable MA, Dukes MA and Nantucket MA
Counties.
* WHEN...For the High Surf Advisory, until 8 PM EDT Sunday. For
the Coastal Flood Warning, from 5 PM this afternoon to 8 PM
EDT Sunday.
* IMPACTS...Strong northeast winds with large waves will result in
minor coastal flooding with pockets of moderate coastal flooding
over multiple high tide cycles from late today through the
weekend. The water also may struggle to vacate the area after
the high tides given persistent strong northeast winds. The
greatest risk for coastal flooding appears to be setting up
south of Boston and onto the Cape and Islands. In addition...the
long duration of northeast winds coupled with large waves over
multiple high tide cycles will result in areas of severe beach
erosion for a prolonged period.
Measurements
| Coordinates | 39.9645, -100.8105 |
|---|---|
| Region | Eastern Essex; Suffolk; Eastern Norfolk; Eastern Plymouth; Barnstable; Dukes; Nantucket |
| Location Precision | country |
| Issuing Authority | United States of America — us-noaa-nws-en |
| Cap Urgency | Expected |
| Cap Certainty | Likely |
| Cap Expires | 2026-09-25T20:30:00-04:00 |
Official source
Warnings courtesy of the issuing national meteorological service, via the WMO Alert Hub.
This is an official warning issued by the authority named above. Follow its instructions and those of your local emergency services.
Severity as published by WMO Alert Hub (national weather services).
View original reportThis event as JSON · API and licence
Source updated 24 days ago (Sep 25, 2026 11:21 UTC) · we last heard from WMO Alert Hub (national weather services) 1 second ago
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About this location
The agency did not publish coordinates for this warning. The pin is the centre of the country, not the location of the event — read the area name, not the map, for where it applies.
Area as the agency stated it: Eastern Essex; Suffolk; Eastern Norfolk; Eastern Plymouth; Barnstable; Dukes; Nantucket
Official authorities in United States
If you are there, these are the bodies whose instructions apply. This site is not an emergency service and does not issue warnings.
More for United States →What to do
Follow the instructions issued by WMO Alert Hub (national weather services) and your local emergency services. The guidance below is background.
Understanding surge zones, evacuation timing, and why storm surge is the deadliest part of a tropical cyclone.
Open Storm Surge Safety Guide →Nearby & related events
Disclaimer: figures are automatic feeds from the named agencies and may be revised. Do not use this page for life-safety decisions — follow official local emergency services.