Gloucester, MA Tide Gauge

Sea Surface Height

Tide gauge located in Gloucester, MA Tide Gauge. Funded by NERACOOS. Data is reported in elevation above MLLW (NAVD88) in feet and also converted to meters. NOAA uses Mean Lower Low Water (MLLW), which is the average height of the lowest tide recorded at a tide station each day during a 19-year recording period, known as the National Tidal Datum Epoch.[5] MLLW is only a mean, so some tidal levels may be negative relative to MLLW; see also mean low water spring. The 19-year recording period is the nearest full year count to the 18.6-year cycle of the lunar node regression, which has an effect on tides. At this location Mean Sea Level (MSL) is 1.453 meters above MLLW Benchmark used: NOAA Station ID: 8441841 - GLOUCESTER HARBOR (with extrapolated estimate) MSL meters = (MLLW ft. * 0.3048) + GAUGE location correction.

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Additional information

Temporal extent	2026-07-21 – 2026-11-04
Date (creation)	2026-11-04
Status	onGoing
Update frequency	asNeeded
Metadata language	en
License	The data may be used and redistributed for free but is not intended for legal use, since it may contain inaccuracies. Neither the data Contributor, ERD, NOAA, nor the United States Government, nor any of their employees or contractors, makes any warranty, express or implied, including warranties of merchantability and fitness for a particular purpose, or assumes any legal liability for the accuracy, completeness, or usefulness, of this information.
Source metadata	ISO 19115 XML
Last updated	2026-11-04
Created	2026-11-04
API	package_show