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
05 March 2024 565 ee6265f86e4ed65f248e2fb1c4263293
Date last upload: 22-FEB-24
Change History Metadata
10 September 2024 565 5ebbdda71d3e274e92cfafed7a289760
Date last upload: 27-JUN-24
Offshore Marine Zones 05 March 2024 130 e8123ba7be54daaaa639a124d0853d76
Date last upload: 22-FEB-24
Change History Metadata
10 September 2024 130 e80394e86aac169aab8079c18ae7e251
Date last upload: 27-JUN-24
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]