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Flood Warning issued September 27 at 11:34AM EDT until September 27 at 2:30PM EDT by NWS Boston/Norton MA

7.0
42.3878°N, 71.4922°W·US-MA
Started 1h ago
NWS flood alerts data as of
Event Details
Typeflood
Severity7.0
Statusactive
Location42.3878°N, 71.4922°W (MA)
Started2026-09-27T15:34:00+00:00
Last Updated2026-09-27T17:10:48.015+00:00
Sourcenoaa_ahps
Source URLapi.weather.gov
Confidence1.00
Impact Zones
Modeled Inundation
Where the National Water Model's latest analysis puts water inside the warning area. Experimental; the warning polygon is the official boundary.
NWS polygon
Severe Impact Zone
Active flood warning area. Significant property damage possible.
NWS polygon

Zone estimates are based on scientific models and may differ from actual local conditions.

Impact Analysis

This event's zone is the NWS warning polygon. Population and structure estimates are not computed inside NWS polygons yet, so none are shown.

Historical Comparison
2010 NORFOLK County, MASSACHUSETTS Flood75% match

Flood in MASSACHUSETTS, 18km from current event, $17M in recorded damage

NORFOLK County, MASSACHUSETTSDamage: $16.6M
2020 NORFOLK County, MASSACHUSETTS Flash Flood74% match

Flash Flood in MASSACHUSETTS, 32km from current event, $30M in recorded damage

NORFOLK County, MASSACHUSETTSDamage: $30.0M
2010 MIDDLESEX County, MASSACHUSETTS Flood74% match

Flood in MASSACHUSETTS, 23km from current event, $26M in recorded damage

MIDDLESEX County, MASSACHUSETTSDamage: $26.4M

Historical comparison based on peril type, geography, and severity. Past events do not predict future outcomes.

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Related
US-MA flood hazard profileAll US hazard profilesScoring methodology

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Zone estimates are based on scientific models and may differ from actual local conditions.