National Weather Service United States Department of Commerce


Overview of Coastal, Offshore and High Seas Marine Zones


Detailed view of the Marine Zones and access to forecasts.
Detailed view of the Offshore Zones and access to forecasts.

Shapefile Type: Polygon

Data source: Coastline derived from US Counties

Naming convention: mzddmmyy (coastal marine zones), ozddmmyy (offshore zones), hzddmmyy (high seas zones)  where ddmmyy = day-month-year

NWS Specifications: NWSI 10-302

Description: The NWS issues marine forecasts, watches, warnings and advisories for a set of defined zone for offshore and coastal waters of the U.S.


Description Valid date Data Download # Records MD5SUM Documentation
Coastal Marine Zones
Including the Great Lakes
02 April 2019 502 F75A4ED3A8B66460BB07755B05158264
Date last upload: 19-APR-19
Change History Metadata
30 March 2021 504 BB0342291B2AD6CCF0531409625FA11B
Date last upload: 03-MAR-21
Offshore Marine Zones 16 April 2019 97 1DAB348E9E87A7CBB912CD9D2A604002
Date last upload: 19-APR-19
Change History Metadata
High Seas Marine Zones 30 June 2017 6 BAB06AE4FDBB224F361AD78977E7637C Change History Metadata


Shapefile Attributes:

Field Name Type width,dec Description
ID character 6 Marine Zone Identifier
WFO character 3 Assigned WFO (Office Identifier)
GL_WFO character 3 Great lakes WFO responsible for Open Lake Forecastts
NAME character 250 Name of Marine Zone
AJOIN0 character 5 Not Used
AJOIN1 character 5 Not Used
LON numeric 10,5 Longitude of Centroid [decimal degrees]
LAT numeric 9,5 Latitude of Centroid [decimal degrees]