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
13 September 2022 507 edd4bc1231093d483f1e137865f69bc7
Date last upload: 19-AUG-22
Change History Metadata
08 March 2023 565 60d2294ce769d00e925ef88da9ec99f2
Date last upload: 14-FEB-23
Offshore Marine Zones 5 April 2022
(ppd from 22 March 2022) 125 45181ea8dedcd03caa905de5ab7b6f65
Date last upload: 16-MAR-22
Change History Metadata
08 March 2023 130 5fb553b16332b0fcc45888c2a2f2f6e3
Date last upload: 14-FEB-23
High Seas Marine Zones 30 June 2017 6 B4702A2B77B16D2EF28C782A464B2DEE 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 (In the offshore zone file, this attribute is "Name")   
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]